PRELUDE FLNG

ENVIRONMENT PLAN
2020
 Shell Australia Pty Ltd Revision 12

Prelude Environment Plan 05/01/2021

Prelude FLNG Environment Plan

Department HSSE&SP

Document Number 2000-010-G000-GE00-G00000-HE-5880-00002

Document Status Issued to NOPSEMA

Revision Number 12

Issue Date 5 January 2021

Owner Prelude Asset Manager

Author/s Prelude Environment Lead

Security Classification Unrestricted

Export Control No US Content

Controlled Document, Copy No: 01

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REVISION HISTORY
Change
Ver. Date Originator Reviewed by Approved by
Description

1 Issued for 23/04/2015 Environment Prelude Technical HSE Lead Prelude

Review Advisor Prelude HSE Manager Project
(Project) Director
Prelude OIM
Logistics Manager
Environment Manager
Services Coordinator
Commissioning Leads
Subsea Engineer
HSSE Advisor
Wells Manager
Start Up Process Engineer
External Affairs Advisor
2 Issued for 12/06/2015 Environment Ver.1 reviewers plus the Prelude
Review Advisor following: Project
(Project) Prelude Asset Manager Director
Prelude Project Director
Prelude Production Manager
General Manager HSSE
Construction Manager
Process Surveillance Lead
Production Chemistry Lead
3 Issued for 15/09/2015 Environment Prelude Technical HSE Lead Prelude
Review Advisor Project
(Project) Director
4 Issued for Use 08/06/2016 Environment Prelude Technical HSE Lead Prelude
Advisor Prelude Asset Manager Project
(Project) Director
Prelude Project Director
Prelude Production Manager
Environment Manager
External Affairs Advisor
Process Surveillance Lead
5 Issued for Use 11/10/2016 Environment Prelude Technical HSE Lead Prelude
Advisor Prelude Production Manager Project
(Project) Director
Environment Manager
External Affairs Advisor
6 Approved for 15/12/2016 Environment N/A Prelude
Use (Accepted Advisor Project
by NOPSEMA) (Project) Director
7 Approved for 07/07/2017 Environment Prelude Environment Prelude Asset
Use Advisor Engineer Manager
(Project) Shell Australia Environment
Advisor
Prelude HSSE Manager
Prelude Production Manager
Prelude Technical HSE Lead

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REVISION HISTORY
Change
Ver. Date Originator Reviewed by Approved by
Description

Environment Technical
Authority
8 Approved for 20/12/2018 Prelude Startup Manager Prelude Asset
Review Environment Prelude HSSE Manager Manager
(incorporated Engineer
EP Changes: Prelude Technology
MEG, MBP, Manager
Boiler Shell Australia Prelude Production Manager
Blowdown, Environment
Advisor QMI Engineer
STP,
Startup Process Engineering
Chemicals,
Lead
Smokeless
Flare, updated Startup Process Engineer
IMS residual
risk
assessment)
9 Approved for 21/12/2018 Prelude Startup Manager Prelude Asset
Use prior to Environment Prelude HSSE Manager Manager
SURU Engineer
Prelude Technology
Manager
Shell Australia Prelude Production Manager
Environment
Advisor QMI Engineer
Startup Process Engineering
Lead
Startup Process Engineer
9.1 Approved for 2/10/2019 Prelude Offshore Installation
Review for Environment Manager
formal EP Engineer Maintenance Manager
resubmission
Snr Process Engineer 3x
Shell Australia Design Process Engineer
Environment
Advisor Production Coordinator
Services Coordinator
Environment Production Chemist
Consultant Snr Instrument Engineer
Principal Environment
Advisor
Emergency Response
Coordinator
Head of Marine
HSSE Advisor
External Relations Advisor
Snr Legal Counsel
10 Approved EP 6/2/2020 Prelude External Relations Advisor Prelude Asset
resubmission Environment Manager
for NOPSEMA Engineer
Assessment
Shell Australia
Environment
Advisor

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REVISION HISTORY
Change
Ver. Date Originator Reviewed by Approved by
Description

11 Response to 4/09/2020 Shell Australia Prelude HSSE Manager Prelude Asset

NOPSEMA Environment Principal Environment Manager
comments Lead Advisor
Emergency Response
Coordinator
HSSE Advisor
Production Chemist
External Relations Advisor
Well Engineering Manager
Snr Legal Counsel
12 Approved for 05/01/2021 Prelude Prelude HSSE Manager Prelude Asset
use. Environment Principal Environment Manager
Response to Lead Advisor
NOPSEMA Shell Australia Environment TA2
comments Environment
Lead Emergency Response
Coordinator
External Relations Advisor
Production Support Manager
Snr Legal Counsel

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TABLE OF CONTENTS

1.0 Environment Plan Summary Statement........................................................... 22

2.0 Introduction ........................................................................................................ 23
3.0 Requirements ..................................................................................................... 24
3.1 Legislation .................................................................................................. 25
3.1.1 Offshore Petroleum and Greenhouse Gas Storage Act 2006........... 25
3.1.2 Environment Protection and Biodiversity Conservation Act 1999 ..... 28
3.1.3 Other Legislation ............................................................................... 34
3.2 Standards and Guidelines .......................................................................... 39
3.2.1 Industry Good Practice Standards .................................................... 39
3.2.2 International Standards and Guidelines ............................................ 39
3.2.3 Shell Health, Security, Safety, Environment and Social Performance
Management Framework .................................................................. 40
3.3 International Agreements and Conventions ............................................... 40
4.0 Shell Environmental Management Framework ............................................... 46
4.1 Shell Health, Security, Safety, Environment and Social Performance
Management Framework ........................................................................... 46
4.2 HSSE & SP Policy...................................................................................... 46
4.3 HSSE & SP Control Framework ................................................................. 47
4.4 HSSE & SP Management System (MS) .................................................... 48
5.0 Stakeholder Consultation ................................................................................. 49
5.1 Background ................................................................................................ 49
5.2 Shell General Business Principles and Stakeholder Engagement ............. 49
5.2.1 Stakeholder Engagement Process ................................................... 50
5.2.2 The Team.......................................................................................... 50
5.2.3 Prelude Stakeholder Engagement Plan ............................................ 51
5.2.4 EP Consultation Strategy .................................................................. 51
5.2.5 Assessment of merits of claims and objections ................................ 54
5.2.6 Summary of Consultation.................................................................. 55
5.2.7 Ongoing Consultation ....................................................................... 81
6.0 Description of the Activity ................................................................................ 82
6.1 Scope of the EP ......................................................................................... 82
6.2 Location and Timing ................................................................................... 84
6.3 Prelude FLNG Facility Overview ................................................................ 84
6.3.1 Prelude Field Safety Zones............................................................... 86

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6.3.2 Subsea Facilities ............................................................................... 87

6.3.3 Turret Mooring System ..................................................................... 90
6.3.4 Turret ................................................................................................ 90
6.3.5 Topsides and Main Deck .................................................................. 91
6.3.6 Water Intake Risers .......................................................................... 94
6.3.7 Substructure...................................................................................... 94
6.4 Operational Activities ................................................................................. 95
6.4.1 Design Basis for Prelude FLNG and Current Status......................... 95
6.4.2 Maintenance, Shutdowns and/or Turnarounds ................................. 96
6.4.3 Preservation and Maintenance of Subsea Equipment ...................... 96
6.4.4 Well Intervention and Workover ........................................................ 99
6.4.5 Light Well Intervention .................................................................... 100
6.4.6 Potential Light Well Intervention Requirements .............................. 102
6.4.7 Isolations from FLNG ...................................................................... 103
6.5 Logistic Support Arrangement .................................................................. 104
6.5.1 Aviation Support Location ............................................................... 104
6.5.2 Infield Support Vessel ..................................................................... 104
6.5.3 Supply Vessels ............................................................................... 104
6.5.4 Accommodation Support Vessels ................................................... 105
7.0 Description of the Receiving Environment ................................................... 105
7.1 Physical Environment............................................................................... 108
7.1.1 Seabed............................................................................................ 108
7.1.2 Climate ............................................................................................ 108
7.1.3 Oceanography ................................................................................ 109
7.1.4 Water Quality .................................................................................. 110
7.1.5 Sediment Quality............................................................................. 111
7.1.6 Air Quality ....................................................................................... 112
7.1.7 Underwater Noise ........................................................................... 113
7.2 Biological Environment ............................................................................. 113
7.2.1 Benthic Communities ...................................................................... 113
7.2.2 Pelagic Communities ...................................................................... 115
7.2.3 Key Ecological Features ................................................................. 116
7.2.4 Threatened Ecological Communities .............................................. 121
7.2.5 Ramsar Wetlands ........................................................................... 121
7.2.6 Commonwealth Marine Area .......................................................... 123

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7.2.7 WA Mainland Coastline................................................................... 123

7.2.8 Threatened and Migratory Species ................................................. 123
7.3 Socio-Economic Environment .................................................................. 155
7.3.1 Heritage .......................................................................................... 155
7.3.2 Marine Protected Areas .................................................................. 159
7.3.3 Fishing Industry............................................................................... 169
7.3.4 Tourism and Recreation.................................................................. 179
7.3.5 Defence........................................................................................... 179
7.3.6 Shipping .......................................................................................... 179
7.3.7 Indonesian Coastline ...................................................................... 180
7.3.8 Oil and Gas Industry ....................................................................... 180
8.0 Acceptable Levels of Impact and Risk for the Petroleum Activities ........... 181
8.1 Considerations in Developing Defined Acceptable Levels of Impact and Risk
................................................................................................................. 181
8.1.1 Principles of Ecologically Sustainable Development ...................... 181
8.1.2 Other Relevant Requirements ........................................................ 182
8.1.3 Significant Impacts to MNES .......................................................... 182
8.1.4 Internal Context............................................................................... 184
8.1.5 External Content ............................................................................. 185
8.1.6 Defined Acceptable Levels of Impact and Risk............................... 185
9.0 Evaluation of Environmental Impacts and Risks .......................................... 190
9.1 Introduction .............................................................................................. 190
9.1.1 Shell Company Approach to Risk Management ............................. 190
9.2 Impact Assessment Methodology ............................................................ 191
9.2.1 Aspects and Impact/Risk Identification ........................................... 192
9.2.2 Evaluation of Impacts...................................................................... 193
9.2.3 Assessment of Residual Impacts and Risks ................................... 198
9.2.4 ALARP Assessment........................................................................ 198
9.3 Physical Presence.................................................................................... 199
9.3.1 Aspect Context................................................................................ 199
9.3.2 Description and Evaluation of Impacts............................................ 199
9.3.3 Impact Assessment Summary ........................................................ 200
9.3.4 ALARP Assessment and Environmental Performance Standards .. 201
9.3.5 Acceptability of Impacts .................................................................. 203
9.3.6 Environment Performance Outcome............................................... 205
9.4 Lighting..................................................................................................... 205

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9.4.1 Aspect Context................................................................................ 205

9.4.2 Description and Evaluation of Impacts............................................ 205
9.4.3 Impact Assessment Summary ........................................................ 210
9.4.4 ALARP Assessment and Environmental Performance Standards .. 211
9.4.5 Acceptability of Impacts .................................................................. 213
9.4.6 Environment Performance Outcomes ............................................. 216
9.5 Noise ........................................................................................................ 216
9.5.1 Aspect Context................................................................................ 216
9.5.2 Description and Evaluation of Impacts............................................ 224
9.5.3 Impact Assessment Summary ........................................................ 227
9.5.4 ALARP Assessment and Environmental Performance Standards .. 228
9.5.5 Acceptability of Impacts .................................................................. 229
9.5.6 Environment Performance Outcome............................................... 233
9.6 Disturbance to Seabed ............................................................................. 234
9.6.1 Aspect Context................................................................................ 234
9.6.2 Description and Evaluation of Impacts............................................ 234
9.6.3 Impact Assessment Summary ........................................................ 235
9.6.4 ALARP Assessment and Environmental Performance Standards .. 236
9.6.5 Acceptability of Impact .................................................................... 237
9.6.6 Environment Performance Outcome............................................... 239
9.7 Vessel Movements ................................................................................... 239
9.7.1 Aspect Context................................................................................ 239
9.7.2 Description and Evaluation of Risks ............................................... 239
9.7.3 Risk Assessment Summary ............................................................ 241
9.7.4 ALARP Assessment and Environmental Performance Standards .. 242
9.7.5 Acceptability of Risks ...................................................................... 244
9.7.6 Environment Performance Outcome............................................... 248
9.8 Introduction of Invasive Marine Species from Vessels ............................. 248
9.8.1 Aspect Context................................................................................ 248
9.8.2 Current Knowledge about IMS on Prelude FLNG and Associated
Vessels ........................................................................................... 249
9.8.3 Description and Evaluation of Impacts and Risks ........................... 254
9.8.4 Risk Assessment Summary ............................................................ 255
9.8.5 ALARP Assessment and Environmental Performance Standards .. 256
9.8.6 Acceptability of Impacts and Risks ................................................. 267
9.8.7 Environment Performance Outcomes ............................................. 270

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9.9 Discharge of Liquid Effluent ..................................................................... 271

9.9.1 Aspect Context................................................................................ 273
9.9.2 Description and Evaluation of Impacts............................................ 280
9.9.3 Cumulative Impact Assessment...................................................... 308
9.9.4 Impact Assessment Summary ........................................................ 314
9.9.5 ALARP Assessment and Environmental Performance Standards .. 315
9.9.6 Acceptability of Impacts .................................................................. 344
9.9.7 Environment Performance Outcomes ............................................. 349
9.10 Atmospheric Emissions ............................................................................ 349
9.10.1 Aspect Context ........................................................................... 349
9.10.2 Description and Evaluation of Impacts ....................................... 356
9.10.3 Impact Assessment Summary .................................................... 370
9.10.4 ALARP Assessment and Environmental Performance Standards
371
9.10.5 Adaptive Stack Monitoring Program ........................................... 380
9.10.6 Acceptability of Impacts .............................................................. 380
9.10.7 Environment Performance Outcome .......................................... 383
9.11 Greenhouse Gas Emissions .................................................................... 383
9.11.1 Aspect Context ........................................................................... 383
9.11.2 Description and Evaluation of Impacts ....................................... 385
9.11.3 Impact Assessment Summary .................................................... 390
9.11.4 ALARP Assessment and Environmental Performance Standards
391
9.11.5 Acceptability of Impacts .............................................................. 409
9.11.6 Environment Performance Outcome .......................................... 414
9.12 Waste Management ................................................................................. 415
9.12.1 Aspect Context ........................................................................... 415
9.12.2 Description and Evaluation of Impacts and Risks ...................... 415
9.12.3 Risk Assessment Summary ........................................................ 417
9.12.4 ALARP Assessment and Environmental Performance Standards
418
9.12.5 Acceptability of Impacts .............................................................. 420
9.12.6 Environment Performance Outcome .......................................... 423
9.13 Emergency Events ................................................................................... 423
9.13.1 Scenario Context ........................................................................ 423
9.13.2 Overview of Unplanned Spill Modelling ...................................... 428

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9.13.3 Summary of Loss of Containment Modelling Results ................. 433

9.13.4 Description and Evaluation of Impacts and Risks ...................... 440
9.13.5 Risk Assessment Summary ........................................................ 461
9.13.6 ALARP Assessment and Environmental Performance Standards
462
9.13.7 Acceptability of Risks .................................................................. 466
9.13.8 Environment Performance Outcome .......................................... 472
9.14 Oil Spill Response Strategies ................................................................... 472
9.14.1 Spill Impact Mitigation Assessment ............................................ 472
9.14.2 Aspect Context ........................................................................... 481
9.14.3 Description and Evaluation of Impacts ....................................... 482
9.14.4 Impact Assessment Summary .................................................... 484
9.14.5 ALARP Assessment and Environmental Performance Standards
485
9.14.6 Acceptability of Impacts .............................................................. 485
9.14.7 Environment Performance Outcome .......................................... 488
10.0 Environmental Plan Implementation Strategy .............................................. 489
10.1 Management Systems ............................................................................. 489
10.1.1 Environment Critical Element Management ............................... 491
10.1.2 Contractor Management ............................................................. 493
10.1.3 Contractor Competency Requirements and Assurance ............. 494
10.1.4 Asset Integrity – Process Safety Management System (AI-PSM)
494
10.1.5 Asset Management System ........................................................ 495
10.1.6 Design and Operational Envelope .............................................. 495
10.1.7 Maintenance & Integrity Execution ............................................. 496
10.1.8 Permit to Work (PTW) ................................................................ 498
10.1.9 Management of Change (MOC) ................................................. 498
10.1.10 Chemical Selection Process ..................................................... 499
10.1.11 Greenhouse Gas and Energy Management System ................ 503
10.2 Organisation, Roles and Responsibilities ................................................. 509
10.3 Competence and Inductions .................................................................... 516
10.3.1 Competency ............................................................................... 516
10.3.2 EP Training ................................................................................. 517
10.4 Monitoring, Assurance and Incident Investigation .................................... 517
10.4.1 Environmental Performance Monitoring ..................................... 518

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10.4.2 FLNG Liquid Discharges Adaptive Monitoring and Management

Framework ...................................................................................... 520
10.4.3 IMS Monitoring, Reporting and Adaptive Management .............. 531
10.4.4 Marine Vessel Assurance ........................................................... 532
10.4.5 Environmental Assurance ........................................................... 534
10.4.6 Environmental Knowledge Management Process ...................... 534
10.4.7 Management Review of EP ........................................................ 535
10.4.8 Management of Incidents and Non-Conformances .................... 535
10.5 Reporting.................................................................................................. 536
10.5.1 Annual Environmental Performance Reporting .......................... 536
10.5.2 External Incident Reporting ........................................................ 536
10.5.3 Internal Reporting ....................................................................... 538
10.5.4 Notifications ................................................................................ 538
10.5.5 Details of Titleholder and Liaison Person ................................... 538
10.6 Record Keeping ....................................................................................... 538
10.7 Emergency Preparedness and Response ............................................... 538
10.7.1 Shell HSSE & CP Control Framework ........................................ 538
10.7.2 Shell Australia Emergency Management Manual ....................... 539
10.7.3 Incident Management Team (West) (IMT(W)) Emergency Response
Plan ................................................................................................. 539
10.7.4 Prelude Facility Emergency Response Plan .............................. 540
10.7.5 Oil Pollution Emergency Plan ..................................................... 540
10.7.6 Operational and Scientific Monitoring Framework ...................... 540
10.7.7 Shell Australia’s Emergency Management Structure ................. 540
10.7.8 Emergency Management Roles and Responsibilities ................ 543
10.7.9 Emergency Management Exercises, Training and Competencies
548
10.7.10 Mechanism to examine the effectiveness of the response
arrangements .................................................................................. 551
11.0 References........................................................................................................ 552
12.0 Disclaimer ......................................................................................................... 575
List of Acronyms ...................................................................................................... 576
13.0 Appendix A: Detailed Facility Description..................................................... 582
13.1 Gas Process Facilities.............................................................................. 582
13.2 Pressure Relief System............................................................................ 583
13.3 Steam, Power Generation & Condensate Recovery ................................ 583
13.4 Seawater Cooling & Essential Seawater Cooling System ....................... 585

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13.5 Water Distillation ...................................................................................... 585

13.6 Electro-chlorination Unit ........................................................................... 587
13.7 Mono-ethylene Glycol (MEG) System ...................................................... 587
13.8 Effluent Treatment and Disposal System ................................................. 588
13.9 Drains ....................................................................................................... 589
14.0 Appendix B: EPBC Act Protected Matters Reports ...................................... 592
15.0 Stakeholder Engagement Materials ............................................................... 593

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List of Tables

Table 3-1: Relationships between OPGGS(E) Regulation 10A requirements and EP

sections......................................................................................................................... 27
Table 3-2: EPBC Approval Conditions (EPBC 2008/4146) and related EP sections ... 29
Table 3-3: Summary of Relevant Legislation ................................................................ 35
Table 3-4: Summary of relevant international agreements and conventions ................ 41
Table 5-1: Guidance for EP Stakeholder Consultation ................................................. 52
Table 5-2: Reasonable Period for Ongoing Consultation ............................................. 53
Table 5-3: Assessment of Relevant Persons for the Activity ........................................ 56
Table 5-4: Stakeholder Consultation Activities During Development of EP .................. 60
Table 5-5: Stakeholder Claims and Objections – Assessment of Merit ........................ 68
Table 5-6: Ongoing Consultation Activities ................................................................... 81
Table 6-1: Prelude Subsea Equipment Description ...................................................... 88
Table 6-2 Prelude Subsea Infrastructure Inventory ...................................................... 89
Table 6-3 Prelude FLNG Name Plate Capacities ......................................................... 96
Table 7-1: Water quality.............................................................................................. 111
Table 7-2: Prelude Baseline Sediment quality results ................................................ 111
Table 7-3: Descriptions of KEFs within the ZPI, including distance from Prelude FLNG
.................................................................................................................................... 117
Table 7-4: Descriptions of Ramsar Wetlands within the ZPI, including distance from
Prelude FLNG ............................................................................................................. 122
Table 7-5: EPBC Act listed threatened and migratory fauna potentially occurring within
the Operational Area and ZPI identified by the PMST reports that may credibly be
impacted by the petroleum activities considered in this EP ........................................ 124
Table 7-6: Conservation advice for EPBC Act listed threatened species identified within
the ZPI considered during environmental risk assessment ........................................ 128
Table 7-7: BIAs and Critical Habitats(*) within the ZPI nearest to Prelude ................. 133
Table 7-8: Key environmental sensitivities and indicative timings for migratory fauna
within the Operational Area and ZPI (North-west Marine Region) .............................. 136
Table 7-9: Commonwealth Heritage Places within the ZPI ........................................ 156
Table 7-10: National Heritage Places within the ZPI .................................................. 158
Table 7-11: MPAs within the ZPI ................................................................................ 160
Table 7-12: Commonwealth fisheries within the ZPI .................................................. 170
Table 7-13: Western Australia fisheries within the ZPI ............................................... 172
Table 7-14: Northern Territory fisheries within the ZPI ............................................... 177
Table 8-1: MNES Significant impact criteria applied to the petroleum activities
considered in this EP .................................................................................................. 182
Table 8-2: Acceptability Categories ............................................................................ 184

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Table 8-3: Summary of acceptable levels of impact for environmental receptors that
may be affected by the petroleum activities considered in this EP ............................. 185
Table 9-1: Definition of Key Terminology for Impact Assessment .............................. 192
Table 9-2: Magnitude Criteria ..................................................................................... 194
Table 9-3: Receptor Sensitivity Criteria ...................................................................... 196
Table 9-4: Impact Consequence Ranking Matrix........................................................ 196
Table 9-5: Likelihood Criteria ...................................................................................... 197
Table 9-6: Environmental Risk Matrix (Unplanned Events) ........................................ 197
Table 9-7: Physical Presence Evaluation of Residual Impacts................................... 200
Table 9-8: ALARP Assessment and Environmental Performance Standards ............ 201
Table 9-9: Acceptability of Impacts – Physical Presence ........................................... 203
Table 9-10: Line of Sight Limits for Turtles ................................................................. 206
Table 9-11: Line of Sight Limits for Migratory Birds and Seabirds .............................. 208
Table 9-12: Light Emissions Evaluation of Impacts .................................................... 210
Table 9-13: ALARP Assessment and Environmental Performance Standards .......... 211
Table 9-14: Acceptability of Impacts - Lighting ........................................................... 213
Table 9-15: Summary of Alignment of the Impacts from Light Emissions Aspect of the
Prelude field with Relevant Requirements for EPBC Threatened Fauna ................... 214
Table 9-16: Maximum Distance from FLNG at Which the Specified Received Levels are
Likely to be Exceeded................................................................................................. 219
Table 9-17: Expected Sound Frequencies and Broadband Source Levels of FLNG and
Support Operations..................................................................................................... 220
Table 9-18: Marine Mammal Sound Exposure Criteria (Continuous Noise) ............... 222
Table 9-19: Sound Frequencies Utilised by Marine Fauna and Known Response Levels
.................................................................................................................................... 223
Table 9-20: Noise Evaluation of Residual Impacts ..................................................... 227
Table 9-21: ALARP Assessment and Environmental Performance Standards .......... 228
Table 9-22: Acceptability of Impacts - Noise .............................................................. 229
Table 9-23: Summary of Alignment of the Impacts from the Noise Aspect of the Prelude
petroleum activities with Relevant Requirements for EPBC Threatened Fauna ........ 232
Table 9-24: Benthic Disturbance Evaluation of Residual Impacts .............................. 235
Table 9-25: ALARP Assessment and Environmental Performance Standards .......... 236
Table 9-26: Acceptability of Impact – Disturbance to Seabed .................................... 237
Table 9-27: Summary of Alignment of the Impacts from the Seabed Disturbance Aspect
of the Prelude Petroleum Activities with Relevant Requirements for MNES .............. 238
Table 9-28: Vessel Collision with Marine Life Evaluation of Residual Risks .............. 241
Table 9-29: ALARP Assessment and Environmental Performance Standards .......... 242
Table 9-30: Acceptability of Risks – Vessel Movements ............................................ 244

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Table 9-31: Summary of Alignment of the Risks from the Vessel Movements Aspect of
the Prelude Petroleum Activities with Relevant Requirements for EPBC Threatened
Fauna.......................................................................................................................... 245
Table 9-32: IMS Evaluation of Residual Risks............................................................ 255
Table 9-33: ALARP Assessment and Environmental Performance Standards .......... 256
Table 9-34: Acceptable Levels of Risks - IMS ............................................................ 267
Table 9-35: Summary of Alignment of the Risks from the IMS Aspect of the Prelude
Petroleum Activities with Relevant Requirements for EPBC Threatened Fauna ........ 269
Table 9-36: Types, location, source depth, discharge depth, flow rates and orientations
of the planned and routine liquid discharges from Prelude FLNG .............................. 271
Table 9-37: Upper bound estimates of sewage, grey water and food waste volumes
and associated calculated nutrient input estimations into the marine environment .... 275
Table 9-38: Estimated Chemical Discharge Types and Typical Volumes during Subsea
Operation, IMR and Intervention Activities ................................................................. 279
Table 9-39: A matrix summarising credibility of interactions with the identified
environmental receptors from the various planned liquid discharge streams ............. 281
Table 9-40: Maximum distances forecast for far field PW dilution levels.................... 295
Table 9-41: Guidelines for chlorine concentration in water......................................... 302
Table 9-42: Liquid Discharges Evaluation of Residual Impacts .................................. 314
Table 9-43: Drainage (Slops) and Bilge Waste Discharges ALARP Assessment and
Environmental Performance Standards ...................................................................... 315
Table 9-44: Sewage, Grey Water and Food Waste Discharges ALARP Assessment
and Environmental Performance Standards ............................................................... 317
Table 9-45: Cooling Water Discharges ALARP Assessment and Environmental
Performance Standards .............................................................................................. 321
Table 9-46: Desalination Brine, MBP and Boiler Blowdown Effluent Discharge ALARP
Assessment and Environmental Performance Standards .......................................... 330
Table 9-47: PW Discharge ALARP Assessment and Environmental Performance
Standards ................................................................................................................... 332
Table 9-48: Use and Discharge of Ad-Hoc Chemicals ALARP Assessment and
Environmental Performance Standards ...................................................................... 340
Table 9-49: Acceptability of Impacts – Discharge of Liquid Effluent ........................... 344
Table 9-50: Summary of Alignment of the impacts from the Liquid Discharges Aspect of
the Prelude Petroleum Activities with Relevant Requirements for MNES .................. 347
Table 9-51: Expected Gaseous Emissions from Combustion Sources of the FLNG .. 350
Table 9-52: Measured Emission Rates for the HP Steam Boilers at FLNG ............... 352
Table 9-53: Prelude FLNG Atmospheric Emissions Inventory ................................... 354
Table 9-54: Range of utilisation days per year from planning assumptions of emissions
forecasts in 2019 ........................................................................................................ 355
Table 9-55: Air Modelling Inputs (on a per stack basis) ............................................. 359

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Table 9-56: Normal Operations Maximum Predicted Concentrations ........................ 360

Table 9-57: Exceptional Case Maximum Predicted Concentrations .......................... 360
Table 9-58: Worst Reasonable Exceptional Case Maximum Predicted Concentrations
.................................................................................................................................... 360
Table 9-59: Ichthys Air Modelling Inputs..................................................................... 363
Table 9-60: Cumulative Prelude and Ichthys Normal Operations Maximum Predicted
Concentrations............................................................................................................ 367
Table 9-61: Cumulative Prelude Exceptional Case and Ichthys Normal Operations
Maximum Predicted Concentrations ........................................................................... 368
Table 9-62: Cumulative Prelude Worst Reasonable Exceptional Case and Ichthys
Normal Operations Maximum Predicted Concentrations............................................ 368
Table 9-63: Atmospheric Pollutant and Air Toxics Emissions Evaluation of Residual
Impacts ....................................................................................................................... 370
Table 9-64: Atmospheric Pollutant and Air Toxic Emissions Evaluation of Residual
Risks ........................................................................................................................... 370
Table 9-65: ALARP Assessment and Environmental Performance Standards .......... 371
Table 9-66: Acceptability of Impacts – Atmospheric Emissions ................................. 380
Table 9-67: Summary of Alignment of the Impacts from the Atmospheric Pollutant
Emissions Aspect of the Prelude petroleum activities with Relevant Requirements for
EPBC Threatened Fauna ........................................................................................... 382
Table 9-68: Prelude FLNG Actual Annual GHG emissions in early start-up phases .. 384
Table 9-69- Comparisons between Prelude FLNG, Australian and Global GHG
emissions .................................................................................................................... 385
Table 9-70: Projected Effects of Climate Change on Key Australian Ecosystems ..... 386
Table 9-71: Greenhouse Gas Emissions Evaluation of Residual Impacts ................. 390
Table 9-72: ALARP Assessment and Environmental Performance Standards ......... 391
Table 9-73: Waste Evaluation of Residual Risks ........................................................ 417
Table 9-74: ALARP Assessment and Environmental Performance Standards .......... 418
Table 9-75: Acceptability of Impacts – Waste Management ....................................... 420
Table 9-76: Summary of Alignment of the Risks from the Waste Aspect of the Prelude
Petroleum Activities with Relevant Requirements for EPBC Threatened Fauna ........ 421
Table 9-77 Summary of Modelled Hydrocarbon and Hazardous Liquids Scenarios .. 428
Table 9-78: Hydrocarbon Exposure Zones and Thresholds ....................................... 430
Table 9-79: Browse JV Ecotox testing on Calliance Condensate............................... 432
Table 9-80: The acute or chronic toxicity of different aquatic organisms and the time
period of exposure ...................................................................................................... 433
Table 9-81: Summary of Combined Hydrocarbon Spill Modelling Results for Sensitive
Receptors with Contact above Moderate Exposure Thresholds and Chemical Spill
Modelling Results ....................................................................................................... 440
Table 9-82: Emergency Events Evaluation of Residual Risks .................................... 461

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Table 9-83: ALARP Assessment and Environmental Performance Standards .......... 462
Table 9-84: Acceptability of Risks – Emergency Events ............................................ 466
Table 9-85: Summary of Alignment of the Impacts from the Emergency Events
associated with the Prelude Petroleum Activities to Relevant Requirements for MNES
.................................................................................................................................... 471
Table 9-86: ALARP assessment of oil spill response capability ................................. 474
Table 9-87: Spill response strategies and associated environmental aspects identified
for each including those that are considered new or unique ...................................... 481
Table 9-88: Spill Response Strategies Evaluation of Residual Impacts ..................... 485
Table 9-89 Acceptability of Impacts – Oil Spill Response Strategies ......................... 485
Table 10-1: HSSE & SP-MS Elements Implementation and Improvement ................ 490
Table 10-2: Technical Integrity management Tools .................................................... 497
Table 10-3: OP20 in plan abatement projects ............................................................ 506
Table 10-4: Key Responsibilities ................................................................................ 510
Table 10-5: Emissions and Discharges Monitoring for Prelude FLNG Facility ........... 518
Table 10-6: FLNG Wastewater Adaptive Monitoring and Management Framework –
Monitoring Programs .................................................................................................. 521
Table 10-7: FLNG Wastewater Discharges – Topsides Monitoring ............................ 523
Table 10-8: Summary of WET Testing ....................................................................... 523
Table 10-9: Summary of the routine/planned infield monitoring campaigns ............... 526
Table 10-10: Summary of the PW Model Verification ................................................. 527
Table 10-11: Summary of the PW Sediment Quality Monitoring ............................... 528
Table 10-12: Prelude PW Discharge Additional Studies Triggers Due to Potential
Changes ..................................................................................................................... 530
Table 10-13: Other Externally Notifiable Incidents ..................................................... 537
Table 10-14: Summary of Roles and Responsibilities of Key Emergency Management
Personnel.................................................................................................................... 543
Table 10-15: Shell Personnel Roles Positioned within the State Maritime Environmental
Emergency Coordination Centre (MEECC)/ DOT IMT ............................................... 545
Table 10-16: Roles and Responsibilities of DoT Personnel to be Positioned in Shell’s
IMT/CMT ..................................................................................................................... 548
Table 10-17: Exercise and Training Requirements for Key ERT, IMT and CMT
Personnel.................................................................................................................... 548
Table 10-18: Oil Spill Responder Training and Resources ......................................... 549
Table 10-19: Exercise Types, Objectives and Frequency .......................................... 550

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List of Figures

Figure 2-1: Prelude FLNG and Associated Subsea Infrastructure Schematic .............. 24
Figure 4-1: Shell Australia’s HSSE & SP Policy ........................................................... 47
Figure 4-2: Shell HSSE & SP Control Framework ........................................................ 48
Figure 5-1: Development of Consultation Strategy ....................................................... 51
Figure 6-1: Prelude EP Operational Area ..................................................................... 83
Figure 6-2: Location of Prelude (Permit Area WA-44-L) ............................................... 84
Figure 6-3: Overview of the Prelude FLNG Facility ...................................................... 86
Figure 6-4: Prelude Field Layout and Safety Zones ..................................................... 87
Figure 6-5: Turret 3D View ........................................................................................... 91
Figure 6-6: Main Deck and Topsides Layout Plan ........................................................ 93
Figure 7-1: ZPI for the Prelude FLNG facility and associated Petroleum Activities .... 107
Figure 7-2: Long-term maximum and minimum temperatures and mean rainfall from
Cygnet Bay (closest Bureau of Meteorology climate station to Prelude FLNG). Data
sourced from Bureau of Meteorology (n.d.) ................................................................ 109
Figure 7-3: Regional synoptic-scale currents off north-western Australia (from DEWHA
2008)........................................................................................................................... 110
Figure 7-4: Prelude FLNG Baseline Sediment Sampling Locations from 2008. ........ 112
Figure 7-5: Locations of KEFs within the ZPI ............................................................. 117
Figure 7-6: Ramsar Wetlands within the ZPI .............................................................. 122
Figure 7-7: BIAs for blue and pygmy blue whales within the ZPI ............................... 138
Figure 7-8: BIAs for humpback whales within the ZPI ................................................ 140
Figure 7-9: Critical habitats for marine turtles within the ZPI ...................................... 144
Figure 7-10: Whale shark foraging BIA within the ZPI ................................................ 150
Figure 7-11: Commonwealth and State Marine Protected Areas within the ZPI ........ 159
Figure 7-12: Shipping levels within the operational area and broader ZPI ................. 180
Figure 9-1: Risk Management Framework (AS/NZS 4360:2004 Risk Management .. 190
Figure 9-2: Definition of Magnitude in the Context of Impact Identification and
Classification............................................................................................................... 194
Figure 9-3: Hierarchy of Controls................................................................................ 199
Figure 9-4: Predicted Maximum Received Levels at Any Depth Due to Non-Offtake
FLNG Facility Noise as a Function of Range and Azimuth......................................... 218
Figure 9-5: Predicted Maximum Received Levels at Any Depth due to Cavitation Noise.
Top Left FLNG Facility Only; Top Right: 2 x Tugs only; Bottom: Combined Effect of
Tugs and FLNG Facility. Note Change in Scale Compared to Previous Figure ......... 219
Figure 9-6: Timeline of Prelude FLNG IMS monitoring program since April 2016 until
December 2019. ......................................................................................................... 250

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Figure 9-7: Locations of all routine planned liquid discharges on the Prelude FLNG.
Numbers correspond with those in Table 9-36. .......................................................... 273
Figure 9-8: View of cooling water discharge ports P53, P54 (inboard pair), P63 and P64
(outboard pair) that discharge rearwards on the starboard side ................................. 284
Figure 9-9: Calculation for the combined distribution of free chlorine in the far-field
accounting for all water discharges under the 95th percentile current. Range rings mark
50 m increments from the stern. The field of effect is illustrated for concentrations >3
ppb free chlorine. The key shows ppb. The gap between the stern and chlorine
distributions represents the near-field zone. ............................................................... 285
Figure 9-10: Excess temperature larger than 3°C (summer scenario, large flow velocity
directed from the outlets) ............................................................................................ 286
Figure 9-11: CORMIX visualisation plot for worst-case winter scenario (low wind, low
flow, downstream). The Near-Field Region (NFR) is indicated in purple. ................... 287
Figure 9-12: Hypochlorite dosed seawater discharge ................................................ 288
Figure 9-13: Designation of the allowed effect distances for the PFW. The left panel
shows the calculation of the effect zone, along the central axis of the vessel. The right
panel shows a plan view of the circles (around the turret) described for the PFW
discharge (dashed black lines). The blue lines designate effect distances of 50, 100
and 200 m from these discharge, as marked. ............................................................ 294
Figure 9-14: Predicted 95th percentile PW dilution (Left) & Predicted 99th percentile
PW dilution (Right) from APASA (2012) ..................................................................... 296
Figure 9-15: Dilution fields calculated for discharge into the wake zone of the FLNG
(strong current, 20% MEG) ......................................................................................... 297
Figure 9-16: Mix of produced water discharge modelling ........................................... 298
Figure 9-17: SSD curves developed from the PW WET testing results from samples
collected from the Prelude FLNG on 29 April (left) and 6 May 2019 (right) ................ 306
Figure 9-18: Calculation for the field of effect of TPH in the far-field resulting from the
PW discharge. The field of effect is illustrated for concentrations > 7 ppb TPH. The key
shows ppb. Range rings mark 25 m distances from the source. The red circle indicates
the end of the near-field zone. The green circle indicates the location of the PW
discharge. ................................................................................................................... 310
Figure 9-19: Calculation for the field of effect of TPH in the far-field resulting from slops
and bilge discharge occurring with all other discharges. The field of effect is illustrated
for concentrations >7 ppb. The key shows ppb. Range rings mark 50 m distances from
the stern. The gap from the stern represents the length of the near-field zone. ......... 311
Figure 9-20: Area Map and Modelled Emission Locations ......................................... 361
Figure 9-21: Excerpt from Ichthys EIS Report indicating emissions volumes ............ 362
Figure 9-22: Prelude Wind Speed Data (2000-2006) ................................................. 364
Figure 9-23: Example - Prelude Normal Operations Predicted NOx Concentrations with
Varying Minimum Wind Speeds.................................................................................. 365
Figure 9-24: Wind Rose for Wind Speed and Direction Data Gathered at Prelude .... 366
Figure 9-25: Exceptional Case Predicted SO2 Concentrations based on Diesel Sulphur
Content of 500ppm ..................................................................................................... 369

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Figure 9-26: Flowchart: Adaptive Response Stack Testing Program ......................... 380
Figure 9-27: Prelude’s GHG emissions inventory during stable operations. .............. 384
Figure 9-28: Extent of the ZPI (low exposure threshold) and the moderate exposure
thresholds (floating, dissolved and entrained) based on the stochastic results of all
worst case credible spill scenarios combined ............................................................. 436
Figure 9-29: Predictions for the partitioning of oil mass over time through weathering
processes for a subsea blowout of Prelude condensate for 80 days (1,600,000 bbl)
(APASA, 2013) ........................................................................................................... 448
Figure 10-1: ECE Identification Process ..................................................................... 492
Figure 10-2: Illustration of the relationship between SCEs and ECEs ........................ 492
Figure 10-3: Shell AI-PSM Focus Areas ..................................................................... 495
Figure 10-4: Maintenance & Integrity Execution Processes ....................................... 497
Figure 10-5: Management of Change Process Steps ................................................. 499
Figure 10-6: Chemical Approval Process ................................................................... 501
Figure 10-7: Environmental Chemical Impact Assessment ........................................ 502
Figure 10-8: Greenhouse Gas and Energy Management Key Processes .................. 503
Figure 10-9: Prelude GHG Abatement Opportunity Identification and screening process
.................................................................................................................................... 505
Figure 10-10: Prelude Asset Core Organisation Structure ......................................... 510
Figure 10-11: Conceptual diagram of adaptive monitoring and management framework
.................................................................................................................................... 522
Figure 10-12: IMS Monitoring and Adaptive Management completed between 2017 and
2019. ........................................................................................................................... 531
Figure 10-13: Biofouling Risk Assessment Template for Domestic Movements ........ 533
Figure 10-14: Shell Australia Emergency and Incident Management System Overview
.................................................................................................................................... 539
Figure 10-15: Emergency Management Escalation Process Adopted by IMT (W) .... 541
Figure 10-16: Incident Management Team (West) (IMT (W)) Structure ..................... 542
Figure 13-1: FLNG Process Unit Block Diagram ........................................................ 582
Figure 13-2: Prelude Utility Concept and Block Scheme ............................................ 584
Figure 13-3: Drainage Zone Areas ............................................................................. 590

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1.0 Environment Plan Summary Statement

This Prelude Environment Plan (EP) summary has been prepared from material
provided in this EP. The summary consists of the following as required by Regulation
11(4):
EP Summary material requirement Relevant section of EP containing EP Summary
material

The location of the activity 6.2

A description of the receiving 7.0

environment

A description of the activity 6.0

Details of the environmental 9.0

impacts and risks

The control measures for the 9.0

activity

The arrangements for ongoing 10.4.1

monitoring of the titleholders
environmental performance

Response arrangements in the oil 9.14 and 10.7

pollution emergency plan

Consultation already undertaken 5.0

and plans for ongoing consultation

Details of the titleholders 10.5.5

nominated liaison person for the
activity

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2.0 Introduction
Shell Australia Pty Ltd (Shell) operates the Prelude Floating Liquefied Natural Gas
(FLNG) Project (EPBC 2008/4146) in the Petroleum Permit Area WA-44-L (Figure 2-1).
Prelude is in Commonwealth marine waters in the northern Browse Basin, 200km
offshore northwest Australia and 460km north-north east of Broome. Shell is the
Titleholder and Operator of Prelude FLNG in joint venture with INPEX, KOGAS and
OPIC.
The Prelude FLNG Project comprises the FLNG facility itself and subsea systems
including: production wells and manifolds; flowlines; riser base manifolds; flexible risers
that transport the gas, condensate and any produced formation water to the FLNG
facility; and umbilicals used to control the wells and associated equipment (Figure 2-1).
The entire Prelude FLNG Project was referred by Shell under the Environment
Protection and Biodiversity Conservation Act 1999 (Cth) (“EPBC Act”) which is further
addressed in Section 3.1.2.
Environmental management for the Prelude FLNG is undertaken in agreement with this
EP, which was prepared in accordance with the requirements of the Prelude FLNG
Project (EPBC 2008/4146) Conditions of Approval (see Section 3.1.2) and the Offshore
Petroleum and Greenhouse Gas Storage (Environment) Regulations 2009 (Cth)
(“OPGGS(E) Regulations”), and describes the following:
• Shell’s Health, Security, Safety and Environment and Social Performance (HSSE and
SP) Commitment and Policy and the environmental performance objectives that derive
from the Policy
• The consultation process undertaken with the Relevant Persons and the associated
resolution of and/or responses to any objections or claims
• The area of operations, the proposed activities and its expected time frame
• The environmental management framework for the activity including legislation and
other requirements
• The existing physical, natural, social and economic environments of the region,
including issues or sensitivities particular to the activity
• The impacts and risks to the environment from both planned (normal) and unplanned
(abnormal) operations
• The Environmental Performance Outcomes (EPOs), Environmental Performance
Standards (EPSs) and Measurement Criteria (MC) against which environmental
performance is measured
• The Implementation Strategy, including key roles and responsibilities that are employed
to achieve the program’s environmental performance goals 1
• A system for documenting, monitoring, reporting and reviewing the success of the
Implementation Strategy to facilitate improvement of environmental performance and
external reporting as required.

1The Prelude FLNG Oil Pollution Emergency Plan (OPEP) (HSE_PRE_013075), APPEA OSMP Framework
and the Operational and Scientific Monitoring Bridging Implementation Plan (HSE_PRE_016370) are
presented as standalone documents, submitted together with this EP.

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Figure 2-1: Prelude FLNG and Associated Subsea Infrastructure Schematic

3.0 Requirements
This section is intended to fulfil the requirements of Regulation 13 (4) of the OPGGS(E)
Regulations and meet NOPSEMA’s expectations stated in the Environment Plan
Content Requirements Guidance Note (2019). Regulation 13 (4) – Requirements of the
OPGGS(E) Regulations stipulates that an EP must:
“(a) describe the requirements, including legislative requirements, that apply to
the activity and are relevant to the environmental management of the activity;
and
(b) demonstrate how those requirements will be met.”
The Environment Plan Content Requirements Guidance Note (NOPSEMA 2019a)
provides additional information on NOPSEMA's expectations of EP content relating to
Regulation 13 (4). NOPSEMA does not expect that requirements that are not relevant
to the environmental management of petroleum activities be included in the EP.
This section contains the following, which are intended to meet the requirements stated
above:
• Legislation (including the EPBC approval conditions applied to the Prelude FLNG
project)
• Standards and guidelines
• International agreement and conventions.

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3.1 Legislation
This section describes the Australian legislation that is applicable to the environmental
management of the petroleum activities within the scope of this EP. The name of each
piece of legislation is provided, along with a description of its relevance to the
petroleum activities. A link to the section of the EP related to how these legislative
requirements have been considered is also provided.
As the planned activities considered in the EP take place entirely in Commonwealth
waters, legislation relating to the environmental management of the petroleum activities
considered in this EP are primarily Commonwealth Acts and subsidiary legislation. Key
Acts include the Offshore Petroleum and Greenhouse Gas Storage Act 2006 (Cth)
(OPGGS Act) and the EPBC Act. These Acts and subsidiary legislation are discussed
in Sections 3.1.1 and 3.1.2 respectively; additional Commonwealth legislation is
considered in Section 3.1.3.
Large volume unplanned hydrocarbon releases may under some circumstances impact
upon the environment within the jurisdiction of the State of Western Australia. Western
Australian legislation that may be applicable to the environmental management of such
hydrocarbon releases has also been considered in Section 3.1.3.

3.1.1 Offshore Petroleum and Greenhouse Gas Storage Act 2006

The OPGGS Act provides the regulatory framework for petroleum exploration,
production and greenhouse gas activities in Commonwealth waters. The OPGGS Act is
supported by a range of subsidiary legislation, including:
• the Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Cth)
which ensure that facilities are designed, constructed, installed, operated, modified and
decommissioned in Commonwealth waters only in accordance with Safety Cases that
have been accepted by NOPSEMA;
• the Offshore Petroleum and Greenhouse Gas Storage (Resource Management and
Administration) Regulations 2011 (Cth) which require that a Well Operations
Management Plan (WOMP) are assessed and accepted by NOPSEMA for existing or
proposed offshore facilities; and
• the OPGGS(E) Regulations.
Of relevance to this activity, under Section 572 of the OPGGS Act, a titleholder is
required to maintain all structures, equipment and property in a title area in good
condition and repair, and to remove property when it is neither used not to be used in
connection with operations authorised by the title.
Maintenance of property etc.
(2) A titleholder must maintain in good condition and repair all structures that are, and all
equipment and other property that is: (a) in the title area; and (b) used in connection with
the operations authorised by the permit, lease, licence or authority.
Removal of property etc.
(3) A titleholder must remove from the title area all structures that are, and all equipment
and other property that is, neither used nor to be used in connection with the operations:
(a) in which the titleholder is or will be engaged; and (b) that are authorised by the permit,
lease, licence or authority.

The requirements under Section 572 (2) and (3) of the OPGGS Act, will be met through
the activity as discussed in the sections further.

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Of particular relevance to this EP are the OPGGS(E) Regulations, which require the
environmental impacts and risks of offshore petroleum and greenhouse gas storage
activities be managed to a level that is acceptable and as low as reasonably
practicable (ALARP). The OPGGS(E) Regulations are discussed further below.
3.1.1.1 Offshore Petroleum and Greenhouse Gas Storage (Environment)
Regulations 2009
The OPGGS(E) Regulations provide for the protection of the environment in
Commonwealth waters by requiring that petroleum and greenhouse gas storage
activities be managed in a way that:
• reduces the environmental impacts and risks of the activity to a level that is ALARP;
• reduces the environmental impacts and risks of the activity to an acceptable level; and
• is consistent with the principles of Ecologically Sustainable Development (ESD), as
defined in section 3A of the EPBC Act, which includes:
o decision-making processes should effectively integrate both long-term and short-
term economic, environmental, social and equitable considerations
o if there are threats of serious or irreversible environmental damage, lack of full
scientific certainty should not be used as a reason for postponing measures to
prevent environmental degradation
o the principle of inter-generational equity—that the present generation should ensure
that the health, diversity and productivity of the environment is maintained or
enhanced for the benefit of future generations
o the conservation of biological diversity and ecological integrity should be a
fundamental consideration in decision-making
o improved valuation, pricing and incentive mechanisms should be promoted.
The methodology applied to assess environmental impacts and risks from the
petroleum activities considered in this EP details how impacts and risks are managed
to a level that is acceptable, ALARP and consistent with the principles of ESD. This
methodology is described in Section 8.0 and Sections 9.1-9.2, with aspect-specific
demonstrations provided in each of the impact and risk assessment in Sections 9.3-
9.14.
Regulation 13(3) of the OPGGS(E) Regulations requires EPs to consider Matters of
National Environmental Significance (MNES) protected under the EPBC Act, including
the following:
• the world heritage values of a declared World Heritage property within the meaning of
the EPBC Act
• the national heritage values of a National Heritage place within the meaning of that Act
• the ecological character of a declared Ramsar wetland within the meaning of that Act
• the presence of a listed threatened species or listed threatened ecological community
within the meaning of that Act
• the presence of a listed migratory species within the meaning of that Act
• any values and sensitivities that exist in, or in relation to, part or all of:
o a Commonwealth marine area within the meaning of that Act
o Commonwealth land within the meaning of that Act.

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MNES that may credibly be impacted, or are at risk of being impacted, are described in
Section 7.0 and are considered in the assessment of environmental impacts and risks.
Regulation 10A of the OPGGS(E) Regulations states the criteria for acceptance of an
EP. These are summarised in Table 3-1, along with the sections of this EP that relate
to each of the criteria.
Table 3-1: Relationships between OPGGS(E) Regulation 10A requirements and EP
sections

OPGGS (E) Requirement Relevant Section of EP

Regulation
10A (a) The EP is appropriate for the Section 6.0 and Section 13.0 detail the
nature and scale of the activity nature and scale of the petroleum
activities considered within this EP.
Section 7.0 describes the environmental
receptors that may credibly be impacted,
or are at risk of being impacted, by the
planned and unplanned activities.
Section 9.3 to Section 9.14 provides the
environmental impact and risk
assessments based on the context
provided by Sections 6.0, Section 7.0 and
Section 13.0 (as well as Shell’s internal
context and the context provided by
Relevant Persons).
10A (b) The EP demonstrates that the Section 9.1 to Section 9.2 details the
environmental impacts and risks method by which Shell demonstrates
of the activity will be reduced to environmental impacts and risks are
ALARP managed to a level that is ALARP.
Aspect-specific ALARP demonstrations
are provided in the impact and risk
assessments provided in Section 9.3 to
Section 9.14.
10A (c) The EP demonstrates that the Section 8.0 details the method by which
environmental impacts and risks Shell demonstrates environmental
of the activity will be of an impacts and risks are managed to a level
acceptable level that is acceptable.
Aspect-specific demonstrations of
acceptability are provided in the impact
and risk assessments provided in Section
9.3 to Section 9.14.
10A (d) The EP provides or appropriate EPOs, EPSs and MCs are detailed in
EPOs, EPSs and MC. Section 9.3 to 9.14.
10A (e) The EP includes an appropriate The implementation strategy for the EP is
implementation strategy and provided in Section 10.0.
monitoring, recording and
reporting arrangements
10A (f) The EP does not involve the Section 6.0 and Section 13.0 detail the
activity or part of the activity, planned petroleum activities considered in
other than arrangements for this EP, none of which will occur within a
environmental monitoring or for World Heritage Area.
responding to an emergency,

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Regulation
being undertaken in any part of
a declared World Heritage
property within the meaning of
the EPBC Act.
10A (g) (i) & The EP demonstrates that: The consultation undertaken in relation to
10A (g) (ii) (i) the titleholder has carried out the EP are detailed in Section 5.0,
the consultations required by including Shell’s responses to any claims
Division 2.2A; and or objections made by Relevant Persons.
(ii) the measures (if any) that the Any management measures adopted in
titleholder has adopted, or response to stakeholder consultation
proposes to adopt, because of outcomes are considered in the aspect-
the consultations are specific impact and risk assessments in
appropriate Section 9.3 to Section 9.14.

10A (h) The EP complies with the Act Section 3.1.1 (i.e. this section) shows the
and the regulations. relationship between the Act, regulations
and components of the EP.

3.1.2 Environment Protection and Biodiversity Conservation Act 1999

The EPBC Act and supporting regulations provide for the protection of the environment
and the conservation of biodiversity in Australia. Amendments to the OPGGS Act and
OPGGS(E) Regulations in February 2014, undertaken as part of the streamlining of
environmental approvals for petroleum activities in Commonwealth waters, require
impacts and risks to matters protected under Part 3 of the EPBC Act (i.e. MNES) be
considered in the EP. Following the streamlining arrangements, NOPSEMA became
the sole environmental regulator for petroleum activities (i.e. regulates activities under
the OPGGS Act and EPBC Act) in Commonwealth waters.
The matters protected under Part 3 of the EPBC Act that are required by the
OPGGS(E) Regulations are outlined above in Section 3.1.1.1 Offshore Petroleum and
Greenhouse Gas Storage (Environment) Regulations. As part of the streamlining
arrangements, matters protected under Part 3 of the EPBC Act must be considered by
NOPSEMA when assessing an EP.
3.1.2.1 Consolidated Approval Conditions
The Prelude FLNG Project was referred for assessment under the EPBC Act in 2008
(EPBC 2008/4146) and was deemed to be a ‘controlled action’. The Project was
assessed through an Environmental Impact Statement (EIS), following which the
Project was approved on 12 November 2010 subject to a series of conditions via
approval decision EPBC 2008/4146. These conditions were varied on 8 September
2015 and the consolidated approval conditions subsequently published. The
consolidated conditions, along with the associated sections of the EP relevant to the
conditions, are provided in Table 3-2.

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Table 3-2: EPBC Approval Conditions (EPBC 2008/4146) and related EP sections

Approval Conditions (EPBC 2008/4146) Relevant EP Sections

1) The person taking the action must submit, for the Minister’s approval, a plan (or plans) for Shell has prepared, submitted for assessment and implemented
managing the offshore impacts of the action. The plan (or plans) must include measures for: EPs for all stages of the Prelude FLNG development to date.
a) Production drilling activities: This EP relates only to the start-up and operations phases of
the action or as amended from time to time.
a) Well locations;
1a) Production drilling activities are beyond the scope of the
b) Drilling fluid types and disposal method;
petroleum activities considered in this EP.
c) Drill cutting disposal method;
1b) Offshore construction and installation activities are
d) Fuel and chemical handling and transfer procedures; beyond the scope of the petroleum activities considered in this
e) Cetacean interaction procedures for supply vessels and aircraft that are consistent with EP.
Part 8 of the Environment Protection and Biodiversity Conservation Regulations 2000; 1c)
and
i) Offtake tanker vetting procedures are provided in
f) Cetacean sightings reporting. Section 10.4.3.
b) Offshore construction and installation, including: ii) The impacts and risks from produced formation
a) Design and construction that allows for the complete removal of all structures and water and naturally occurring radioactive materials,
components above the seafloor during decommissioning; along with monitoring and management measures,
b) Details of the anchor type and placements, methods for connection of mooring lines, are assessed in Section 9.9, Section 9.12 and
installation of the risers and flowline paths; Section 10.4.1.
c) Measures to minimise seabed disturbance; iii) The impacts and risks from artificial lighting and
noise, along with monitoring and management
d) Hydrotest fluid type, handling and disposal methods; measures, are assessed in Section 9.4 and Section
e) Cetacean interaction procedures for supply vessels and aircraft that are consistent with 9.5.
Part 8 of the Environment Protection and Biodiversity Conservation Regulations 2000; iv) Procedures for supply vessels and aircraft that are
f) Cetacean sightings reporting; and consistent with Part 8 of the Environment Protection
g) Measures for reporting environmental incidents. and Biodiversity Conservation Regulations 2000 are
c) Operations, including: provided in Section 9.5 and Section 9.7.
a) Offtake tanker vetting procedures; v) Measures for reporting environmental incidents are
provided in Section 10.5.2.
b) Produced formation water and naturally occurring radioactive materials monitoring and
management; This EP was originally submitted greater than two months prior
to commencing Prelude FLNG operations.

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Approval Conditions (EPBC 2008/4146) Relevant EP Sections

c) Measures to reduce artificial lighting and noise associated with operation;
d) Cetacean interaction procedures for supply vessels and aircraft that are consistent with
Part 8 of the Environment Protection and Biodiversity Conservation Regulations 2000;
e) Cetacean sightings reporting; and
f) Measures for the reporting of environmental incidents.
The plan (or plans) must be submitted at least two months prior to the commencement of these
activities. Individual offshore activities, as defined within these conditions, may not commence until
the plan (or plans) for that specific activity have been approved. The approved plan (or plans) must
be implemented.
4) The person taking the action must develop and submit to the Minister for approval, an Oil Spill Shell has undertaken a detailed hydrocarbon spill risk
Contingency Plan that demonstrates the response preparedness of the person taking the action assessment, developed an Oil Pollution Emergency Plan
for any hydrocarbon spills, including the capacity to respond to a spill and mitigate the (OPEP) (HSE_PRE_013075) and an associated Operational
environmental impacts. The Plan must include, but is not limited to: and Scientific Monitoring Plan (OSMP) (which includes the
a) Oil spill trajectory modelling for potential spills from the action. This should include APPEA OSMP Framework and supporting Operational and
consideration of a well blow out or uncontrolled release. The modelling should be specific to Scientific Monitoring Bridging and Implementation Plan) which
the characteristics of the hydrocarbons contained in the Prelude gas field, the likely volumes combined with this EP, meet the requirements of condition 4 as
released in a worst-case scenario spill, and the potential time over which the oil may be per the following:
released in a worst-case scenario spill, including a scenario of eleven (11) weeks
uncontained spill. a) Key outputs from oil spill trajectory modelling for
b) A description of resources available for use in containing and minimising impacts in the event potential spills are provided in Section 9.13.
of a spill and arrangements for accessing these. b) Spill resource availability and access requirements are
c) A demonstrated capacity to respond to a spill at the site, including application of dispersants, addressed in the OPEP.
if required and appropriate, and measures that can feasibly be applied within the first 12 c) Demonstrated capacity (including dispersant
hours of a spill occurring. application) to respond to a spill is provided for in the
d) Identification of sensitive areas that may be impacted by a potential spill, in particular Browse OPEP.
Island, specific response measures for these areas and prioritisation of these areas during a d) Environmental sensitivities (including Browse Island)
response. located within the Zone of Potential Impact (ZPI) are
e) Training of staff in spill response measures and identifying roles and responsibilities of described in Section 9.13. Specific response measures
personnel during a spill response. for Browse Island and the Spill Impact Mitigation
f) Procedures for reporting oil spill incidents. Assessment (SIMA) process are provided in the OPEP.

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Approval Conditions (EPBC 2008/4146) Relevant EP Sections

The Oil Spill Contingency Plan must be submitted at least three months prior to the commencement e) Training requirements for personnel undertaking oil spill
of drilling activities. The person taking the action must not commence Prelude production drilling response are provided in Section 10.7.9. Roles and
activities until the Oil Spill Contingency Plan is approved. The approved Oil Spill Contingency Plan responsibilities for spill response are contained within
must be implemented. the OPEP.
f) Requirements for reporting oil spill incidents are
provided in Section 10.5.2 and the OPEP.
5) The person taking the action must develop and submit to the Minister for approval, and As stated above, Shell has adopted an OSMP that may be
Operational and Scientific Monitoring Program that will be implemented in the event of an oil spill implemented in the event of a hydrocarbon spill. The OSMP
to determine the potential extent and ecosystem consequences of such a spill, including, but not scales in response to the nature and scale of the spill and the
limited to: environmental receptors at risk. The OSMP has discrete
a) Triggers for the initiation and termination of the Operational and Scientific Monitoring initiation and termination criteria for each of the components of
Program, including, but not limited to, spill volume, composition, extent, duration and the OSMP.
detection of impacts; The OSMP includes consideration of baseline data and provides
b) A description of the studies that will be undertaken to determine the operational response, for sampling of receptors identified at being at risk prior to being
potential extent of impacts, ecosystem consequences and potential environmental contacted by hydrocarbons in the event of a spill.
reparations required as a result of the oil spill. The arrangements by which Shell maintains preparedness to
c) Inclusion of sufficient baseline information on the biota and the environment that may be implement operational and scientific monitoring are detailed in
impacted by a potential hydrocarbon spill, to enable an assessment of the impacts of such a the OSMP, the OPEP and Section 10.7.
spill.
d) A strategy to implement the scientific monitoring plan, including timelines for delivery of
results and mechanisms for the timely peer review of studies, and
e) Provision for periodic review of the program.
The Operational and Scientific Monitoring Program must be submitted at least three months prior to
the commencement of drilling activities. The person taking the action must not commence Prelude
production drilling activities until the Operational and Scientific Monitoring Program is approved. The
approved Operational and Scientific Monitoring Program must be implemented.
7) The person taking the action must submit a Decommissioning Plan to the Minister for approval No decommissioning activities are planned as part of the
one year prior to the decommissioning of the Prelude Floating Natural Gas Facility or any subsea petroleum activities considered in this EP.
wells, flowlines or associated infrastructure. The Decommissioning Plan must consider the

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complete removal of all structures and components above the sea floor. The approved
Decommissioning Plan must be implemented.
11) The person taking the action may choose to revise a management plan approved by the Minister Shell may revise the EP, OPEP and OSMP without providing
under conditions 1, 4, 5 and 7 without submitting it for approval under section 143A of the EPBC notification to the Minister or NOPSEMA if no significant new
Act, if the taking of the action in accordance with the revised plan would not be likely to have a environmental risks/impacts or increases to identified
new or increased impact. If the person taking the action makes this choice they must: environmental risks/impacts considered in these plans are
i) Notify the Department in writing that the approved plan has been revised and provide the identified. Triggers for submission of an EP revision to
Department with an electronic copy of the revised plan; NOPSEMA are provided in Section 10.1.9.
ii) Implement the revised plan from the date that the plan is submitted to the Department;
and
iii) For the life of this approval, maintain a record of the reasons the person taking the action
considers that taking the action in accordance with the revised plan would not be likely to
have a new or increased impact.
11A) The person taking the action may revoke their choice under condition 11 at any time by Shell does not intend to revoke their choice in relation to the
notice to the Department. If the person taking the action revokes the choice to implement a revised submission of plans detailed in condition 11. If Shell do elect to
plan, without approval under section 143A of the Act, the plan approved by the Minister must be revoke their choice, they will implement the plan approved by
implemented. the Minister.
11B) If the Minister gives a notice to the person taking the action that the Minister is satisfied that Shell accepts that any new or increased impact in a revision to a
the taking of the action in accordance with the revised plan would be likely to have a new or management plan specified in condition 11 will result in
increased impact, then: condition 11 not being applicable and Shell will implement the
i) Condition 11 does not apply, or ceases to apply, in relation to the revised plan; and plan accepted by the Minister.
ii) The person taking the action must implement the plan approved by the Minister.
To avoid any doubt, this condition does not affect any operation of conditions 11 and 11A in
the period before the day the notice is given.
At the time of giving the notice the Minister may also notify that for a specified period of time
that condition 11 does not apply for one or more specified plans required under the approval.
11C) Conditions 11, 11A and 11B are not intended to limit the operation of section 143A of the Act Not directly applicable to this EP.
which allows the person taking the action to submit a revised management plan to the Minister for
approval.

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Approval Conditions (EPBC 2008/4146) Relevant EP Sections

14) A plan or program required by condition 1, 4 or 5 has been approved by the Minister and the Noted – Shell intends to meet the requirements of the
measures (as specified in the relevant conditions) are included in an environment plan (or consolidated conditions detailed in EPBC 2008/4146 by
Environment Plans) that: submitting the EP, OPEP and OSMP to NOPSEMA.
a) Was submitted to NOPSEMA after 27 February 2014; or
b) Either:
i) Is in force under the OPGGS Environment Regulations; or
ii) Has ended in accordance with regulation 25A of the OPGGS Environment Regulations.
14A) Where a plan or program required by condition 1, 4 or 5 has been approved by the Minister Shell has submitted the plans required by conditions 1, 4 and 5
and the measures (as specified in the relevant condition) are included in an environment plan (or to NOPSEMA as part of an EP submission for the activity.
Environment Plans) that:
a) Was submitted to NOPSEMA after 27 February 2014; or
b) Either:
i) Is in force under the OPGGS Environment Regulations; or
ii) Has ended in accordance with regulation 25A of the OPGGS Environment Regulations.
the plan or program approved by the Minister no longer needs to be implemented provided
the environment plan remains in force.
14B) Where an environment plan, which includes measures specified in the conditions referred to Shell intends to comply with the conditions in the EP
in conditions 14 and 14A above, is in force under the OPGGS Environment Regulations that relates submissions made to NOPSEMA.
to the taking of the action, the person taking the action must comply with those measures as specified
in that environment plan.

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3.1.2.2 Australian Marine Park Management Plans

The EPBC Act provides for the declaration of Australian Marine Parks (AMPs) based
on the International Union for the Conservation of Nature (IUCN) principles and
guidelines for categorising protected areas. Australia has established a network of
AMPs throughout Commonwealth waters, which are managed under a series of region-
based management plans. These plans detail the management objectives of the
AMPs, the environmental values within each of the AMPs and the activities that area
permissible within the zones of the AMPs. AMPs are part of the Commonwealth Marine
Area, which is an MNES.
The planned petroleum activities considered within this EP will not credibly impact upon
any AMPs, however an unplanned hydrocarbon spill from a worst-case loss of well
containment was identified as potentially impacting upon several AMPs. These AMPs
are described in Section 7.3.2 and managed under the Australian Marine Parks - North
Marine Parks Network Management Plan 2018 (Director of National Parks 2018a) and
Australian Marine Parks - North-west Marine Parks Network Management Plan 2018
(Director of National Parks 2018b).
The requirements of the management plans for AMPs are considered as part of Shell’s
determination of the acceptability of environmental impacts and risks. Refer to Section
9.3 to Section 9.14 for further information.
3.1.2.3 Recovery Plans and Conservation Advice
Species and communities listed as threatened under the EPBC Act are MNES and
receive protection under Commonwealth law. The Threatened Species Scientific
Committee may publish conservation advice for a threatened species, which provides
information on threats and conservation management. Recovery plans relating to
threatened species may also be published by the Commonwealth Department of the
Environment and Energy. Recovery plans are intended to provide a framework to
prevent further decline, and facilitate the recovery, of threatened species. Recovery
plans may contain actions that warrant consideration during the assessment of
environmental impacts and risks. Recovery plans may also identify habitat critical for
the survival of a species; such habitat is protected under the EPBC Act.
Shell has identified a number of threatened species that may credibly be impacted, or
are at risk of being impacted, by the petroleum activities considered in this EP. Details
on these species, along with relevant information from recovery plans and conservation
advice, are provided in Section 7.2.8.

3.1.3 Other Legislation

Other legislation applicable to the environmental management of the petroleum
activities considered in this EP, along with a justification as to why they are relevant,
are provided in Table 3-3.

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Table 3-3: Summary of Relevant Legislation

Legislation Summary Relevance to the Project

Australian Heritage Council Act 2003 This Act identifies areas of heritage value, including The EP will take into consideration any heritage
those listed on the World Heritage List, National values (see Section 7.3.1 for details).
Heritage List and the Commonwealth Heritage List (all
of which are MNES under the EPBC Act).
Australian Maritime Safety Authority Act 1990 Provides that a function of AMSA is to combat Vessel emergencies, including oil spills in
pollution in the marine environment. AMSA is the Commonwealth waters.
control agency for vessel-based non-petroleum
activity spills in commonwealth waters.
Biodiversity Conservation Act 2016 (WA) Requires WA conservation management agencies to Oiled wildlife response will comply with this Act.
Biodiversity Conservation Regulations 2018 take a lead role in oiled wildlife response in Western
Australia. DBCA has the responsibility and statutory
authority to treat, protect and destroy wildlife.
Biosecurity Act 2015 The Act and its supporting legislation are the primary The EP will comply with biosecurity requirements,
legislative means for managing risk of pests and specifically in relation to biofouling and ballast water
diseases entering Australian territory. The Act requirements.
includes requirements for pre-arrival reporting, ballast
water management plans and certificates.
Emergency Management Act 2005 (WA) Requires the WA DoT (Hazard Management Agency) Emergencies including oil spills which enter state
shall be the Control Agency for spills within or entering waters.
WA state waters. It is the legislative basis for the WA
WestPlan – MOP.
Environment Protection (Sea Dumping) Act 1981 This Act protects is intended to prevent pollution of the Chemical inventories onboard the Prelude FLNG
sea by prohibiting the discharge of potentially harmful facility may potentially breach this convention if
materials to the sea. unpermitted via this EP and deliberately discharged to
the sea.
Hazardous Waste (Regulation of Exports and Imports) This Act regulates the export, import and transport of The project will comply with the export, import and
Act 1989 hazardous waste to ensure that hazardous waste is transport requirements for hazardous waste.
managed appropriately so that human health and the

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Legislation Summary Relevance to the Project

environment are protected from the harmful effects of
the waste.
National Environment Protection (National Pollutant This measure provides the framework for the The project will comply with the NPI NEPM through
Inventory) Measure 1998 (established under the development and establishment of the National the reporting of relevant NPI substances.
National Environment Protection Council Act 1994) Pollutant Inventory (NPI), which provides publicly
available information on the types and amounts of 93
toxic substances being emitted into the Australian
environment. These substances have been identified
as important due to their possible effect on human
health and the environment.
National Environment Protection Council Act 1994 This Act establishes the National Environment The project will comply with the requirements of the
Protection Council (NEPC). The primary functions of relevant NEPMs.
the NEPC are to define National Environment
Protection Measures (NEPMs) to ensure that
Australians have equivalent protection from air, water,
soil and noise pollution, and assess and report the
implementation and effectiveness of NEPMs.
National Greenhouse and Energy Reporting Act 2007 The Act provides a single, national framework for the Shell reports as a corporate group under the Act
National Greenhouse and Energy Reporting reporting and distribution of information related to which includes emissions from the Prelude FLNG.
(Safeguard Mechanism) Rule 2015 greenhouse gas (GHG) emissions, GHG projects, Prelude FLNG has committed to a baseline under the
energy production and energy consumption. Reporting Safeguard Mechanism requirement.
obligations are imposed upon corporations that meet
emissions/energy thresholds.
The Act includes National Greenhouse and Energy
Reporting (NGER) requirements and the Safeguard
Mechanism requirements.
Navigation Act 2012 This Act relates to maritime safety and the prevention The project, including vessels, will adhere to the Act
Navigation Regulations 2013 of pollution of the marine environment in Australian and subsidiary legislation enabled by the Act, such as
waters. It gives effect to several international Marine Orders relating to the international conventions
Marine Order 21 (Safety and emergency
conventions relating to maritime issues to which listed in Section 3.3.
arrangements) 2016
Australia is a signatory. The Act also has subordinate

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Legislation Summary Relevance to the Project

Marine Order 27 (Safety of navigation and radio legislation contained in Regulations and Marine
equipment) 2016 Orders.
Marine Order 28 (Operations standards and
procedures) 2015
Marine Order 30 (Prevention of collisions) 2016
Marine order 60 (Floating offshore facilities) 2001
Marine Order 71 (Masters and deck officers) 2014
Ozone Protection and Synthetic Greenhouse Gas The Act protects the environment by reducing The project will adhere to restrictions on import and
Management Act 1989 and Regulations 1995 emissions of ozone depleting substances (ODSs) and use of ODSs/SGGs through implementing appropriate
synthetic greenhouse gases (SGGs). It controls the measures that control procuring of products which
manufacture, import and export of ODSs and SGGs contain these gases.
and products containing these gases.
Protection of the Sea (Prevention of Pollution from The Act regulates discharges from ships to protect the The FLNG and vessels within the Operational Area
Ships) Act 1983 sea from pollution. This includes regulation of are subject to this Act and will adhere to the
Protection of the Sea (Prevention of Pollution from discharges of oil or oily mixtures, noxious liquid requirements for discharges and waste management
Ships) (Orders) Regulations 1994 substances, packaged harmful substances, sewage outlined in the relevant MARPOL and Marine Orders
and garbage to the sea. The Act imposes a duty to (as appropriate to vessel class).
Marine Order 91 (Marine pollution prevention — oil)
report certain incidents involving prohibited discharges
2014
and to maintain record books and management plans.
Marine Order 93 (Marine pollution prevention —
noxious liquid substances) 2014
The Act and subsidiary Marine Orders enact the
Marine Order 94 (Marine pollution prevention —
International Convention for the Prevention of
packaged harmful substances) 2014
Pollution from Ships, 1973 as modified by the Protocol
Marine Order 95 (Marine pollution prevention — of 1978 (MARPOL).
garbage) 2018
Marine Order 96 (Marine pollution prevention —
sewage) 2018
Marine Order 97 (Marine pollution prevention — air
pollution) 2013

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Legislation Summary Relevance to the Project

Underwater Cultural Heritage Act 2018 An Act to protect Australia’s underwater cultural Planned petroleum activities will not interfere with any
heritage. The Act came into effect on 1 July 2019, underwater cultural heritage sites (see Section 7.3.1
replacing the Historic Shipwrecks Act 1976. This act for details).
protects Australia’s shipwrecks, and broadens
protection to sunken aircraft and other types of
underwater cultural heritage.

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3.2 Standards and Guidelines

3.2.1 Industry Good Practice Standards

In Australia, the petroleum exploration and production industry operate within an
industry code of environmental practice developed by the Australian Petroleum
Production and Exploration Association (APPEA) (APPEA 2008). This code provides
guidelines for activities and has evolved from the collective knowledge and experience
of the oil and gas industry both nationally and internationally. The code provides the
Australian petroleum industry with guidance on management measures to protect the
environment during exploration, production and decommissioning phases. Shell is a
signatory to the APPEA guidelines and will align with their intent in the implementation
of this EP.
The following Australian guidelines are also applicable to the project:
• GN1344 Environment Plan Content Requirements Guidance Note (NOPSEMA 2019a)
• GN1785 Petroleum activities and Australia marine parks (NOPSEMA 2018a)
• GN1488 Oil Pollution Risk Management (NOPSEMA 2018b)
• IP1349 Operational and Scientific Monitoring Programs (NOPSEMA 2016)
• IP1765 Acoustic impact evaluation and management (NOPSEMA 2018c)
• Australian Ballast Water Management Requirements (Department of Agriculture and
Water Resources 2017)
• National Biofouling Management Guidance for the Petroleum Production and
Exploration Industry 2009 (Department of Agriculture, Fisheries and Forestry 2009)
• Technical Guideline for the Preparation of Marine Pollution Contingency Plans for
Marine and Coastal Facilities (AMSA 2015)
• Advisory Note for Offshore Petroleum Industry Consultation with Respect of Oil Spill
Contingency Plans (AMSA 2018), and the corresponding Marine Oil Pollution:
Response and Consultation Arrangements (Department of Transport 2020).
The following international guidelines are also applicable to the project:
• Improving Social and Environmental Performance: Good Practice Guidance for the Oil
and Gas Industry (IPIECA 2017)
• Environmental Management in Oil and Gas Production (United Nations Environment
Program and Oil Industry International Exploration and Production Forum 1997).

3.2.2 International Standards and Guidelines

Shell refers to World Bank (WB)/International Finance Corporation (IFC) guidelines as
the basis for many of its operation guidelines, as aligned with the Shell HSSE & SP
Control Framework. The WB/IFC guidelines are the minimum environmental, social
and health standards for WB funded projects, unless the standards of the host country
are more stringent.
The WB/IFC guidelines of primary relevance to the project include:
• IFC Performance Standards on Environmental and Social Sustainability (IFC 2012)
• General Environmental, Health, and Safety (EHS) Guidelines (IFC 2007)
• EHS Guidelines for Offshore Oil and Gas Development (IFC 2015).

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3.2.3 Shell Health, Security, Safety, Environment and Social

Performance Management Framework
Shell maintains and implements a Health, Security, Safety, Environment and Social
Performance Management Framework, which contains a range of standards and
guidelines. It is the means by which Shell ensures that the industry good practice
standards and international standards and guidelines detailed in Sections 3.2.1 and
3.2.2 are implemented. It forms the basis of the implementation strategy of this EP.
Refer to Section 4.0 for further information.

3.3 International Agreements and Conventions

Australia is signatory to several international conventions and agreements that are
relevant to the environmental management of the petroleum activities considered in
this EP. These are typically implemented by Commonwealth legislation, much of which
is detailed above in Section 3.1. Relevant international agreements and conventions,
along with a justification of their relevance to the petroleum activities considered in this
EP, are provided in Table 3-4.

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Table 3-4: Summary of relevant international agreements and conventions

Agreement / Convention Summary Relevance to the Project

Convention on the Conservation This convention aims to conserve migratory fauna species Several species listed as migratory under the EPBC Act were
of Migratory Species of Wild throughout their ranges, particularly where their range crosses identified as potentially being impacted by the petroleum activities
Animals 1979 (the Bonn international jurisdictional boundaries. It is implemented in considered in this EP. Refer to Section 7.2.8.
Convention) Commonwealth law by the EPBC Act, which makes provision for
species listed under the Bonn Convention to be listed as
migratory under the EPBC Act. Species listed as migratory under
the EPBC Act are MNES.
The East Asian - Australasian Adopted in the list of the World Summit on Sustainable Several migratory birds species that utilise the East Asian -
Flyway Partnership 2006 Development as a Type II initiative which is informal and Australasian Flyway were identified as potentially being impacted
(EAAFP) voluntary, the Partnership was launched on 6 November 2006 by the petroleum activities considered in this EP. Section Refer to
and aims to protect migratory waterbirds, their habitat and the Section 7.2.8.
livelihoods of people dependent upon them. There are currently
37 Partners including 18 countries, 6 intergovernmental
agencies, 12 international non-governmental organisations
(NGOs) and 1 international private enterprise.
The Agreement on the ACAP through its 13 Parties strives to conserve albatrosses and Several albatross and petrel species were identified as potentially
Conservation of Albatrosses and petrels by coordinating international activities to mitigate threats being impacted by the petroleum activities considered in this EP.
Petrels (ACAP) to their populations. Section Refer to Section 7.2.8.
Agreement between the This agreement aims to conserve migratory bird species that Several birds listed as migratory under the EPBC Act were
Government of Australia and the travel between Japan and Australia. This includes many species identified as potentially being impacted by the petroleum activities
Government of Japan for the of shorebirds that use the East Asian - Australasian Flyway. It is considered in this EP. Section Refer to Section 7.2.8.
Protection of Migratory Birds in implemented in Commonwealth law by the EPBC Act, which
Danger of Extinction and their makes provision for species listed under JAMBA to be listed as
Environment 1974 (JAMBA) migratory under the EPBC Act. Species listed as migratory under
the EPBC Act are MNES.
Agreement between the This agreement aims to conserve migratory bird species that Several birds listed as migratory under the EPBC Act were
Government of Australia and the travel between China and Australia. This includes many species identified as potentially being impacted by the petroleum activities
Government of the People’s of shorebirds that use the East Asian - Australasian Flyway. It is considered in this EP. Refer to Section 7.2.8.
Republic of China for the implemented in Commonwealth law by the EPBC Act, which

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Protection of Migratory Birds and makes provision for species listed under CAMBA to be listed as
their Environment 1986 migratory under the EPBC Act. Species listed as migratory under
(CAMBA) the EPBC Act are MNES.
Agreement between the This agreement aims to conserve migratory bird species that Several birds listed as migratory under the EPBC Act were
Government of Australia and the travel between the Republic of Korea and Australia. This identified as potentially being impacted by the petroleum activities
Government of the Republic for includes many species of shorebirds that use the East Asian - considered in this EP. Refer to Section Refer to Section 7.2.8.
Korea for the Protection of Australasian Flyway. It is implemented in Commonwealth law by
Migratory Birds and their the EPBC Act, which makes provision for species listed under
Environment 2007 (ROKAMBA) ROKAMBA to be listed as migratory under the EPBC Act.
Species listed as migratory under the EPBC Act are MNES.
International Convention on This convention aims to conserve and promote the sustainable The Ashmore Reef Ramsar wetland was identified as potentially
Wetlands of International human use of wetlands. Many wetlands have been identified as being impacted in the event of an unplanned release of large
Importance 1975 (Ramsar) important habitat for migratory bird species, and Ramsar volumes of hydrocarbons (e.g. loss of well control). Refer to
wetlands are of importance in conserving many species of Section 7.2.5.
migratory shorebirds and waders. Ramsar wetlands are
protected under the EPBC Act and are MNES.
Memorandum of Understanding This memorandum recognises the long history of traditional The Prelude FLNG Project is situated within the MoU box. Refer to
between the Government of Indonesian fishermen exploiting biological resources within Timor Section 7.3.3.
Australia and the Government of Sea waters within Australia’s exclusive economic zone. The
the Republic of Indonesia memorandum provides for an area (commonly referred to at the
Regarding the Operations of MoU box) within which traditional Indonesian fishing is permitted.
Indonesian Traditional The area includes several offshore reefs, including Ashmore
Fishermen in Areas of the Reef, Cartier Island, Scott Reef and Seringapatam Reef.
Australian Exclusive Fishing
Zone and Continental Shelf 1974
London Convention on the This convention is an agreement to control pollution of the sea by Chemical inventories onboard the Prelude FLNG facility may
Prevention of Marine Pollution intentional disposal at sea of potentially harmful materials. It is potentially breach this convention if unpermitted via this EP and
by Dumping of Wastes and implemented under Commonwealth law by the Environment deliberately discharged to the sea.
Other Matter 1972 (London Protection (Sea Dumping) Act 1981.
Convention)

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Agreement / Convention Summary Relevance to the Project

Minamata Convention on This convention is an agreement to protect human and Petroleum production by the Prelude FLNG may result in mercury
Mercury 2017 environmental health from the effects of releases of mercury and compounds being produced from petroleum reservoirs as a by-
mercury-containing compounds to the environment. The product. Mercury may pose a risk to the environment if not
convention is not yet ratified by Australia, and hence is not managed appropriately.
currently implemented in Commonwealth law. Australia has
signed the convention and is currently undertaking an
assessment process prior to ratification.
International Convention for the This convention is an agreement to minimise the pollution of the All marine support vessels are required to comply with MARPOL.
Prevention of Pollution from marine environment by ships. The convention provides a
Ships, 1973 as modified by the standardised approach to the environmental management of
Protocol of 1978 (MARPOL) international and domestic shipping. The convention is
implemented in Commonwealth law by the Protection of the Sea
(Prevention of Pollution from Ships) Act 1983 and a series of
Marine Orders made under this Act.
International Convention on This convention provides a standardised approach to the All project vessels and crew are required to comply with STCW.
Standards of Training, qualifications and competencies of masters, officers and watch
Certification and Watchkeeping personnel. It is implemented in Commonwealth law by the
for Seafarers 1978 (STCW) Navigation Act 2012 and a series of Marine Orders made under
this Act.
International Convention for the This convention provides internationally agreed minimum All project vessels are required to comply with SOLAS.
Safety of Life at Sea 1974 standards for the construction, equipment and operation of
(SOLAS) vessels. It is implemented in Commonwealth law by the
Navigation Act 2012 and a series of Marine Orders made under
this Act.
International Regulations for These regulations provide internationally agreed rules for the All project vessels are required to comply with COLREGS.
Preventing Collisions at Sea navigation of vessels, which are intended to reduce the likelihood
1972 (COLREGS) of vessel collisions. COLREGS are implemented in
Commonwealth law by the Navigation Act 2012 and a series of
Marine Orders made under this Act.

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Agreement / Convention Summary Relevance to the Project

Paris Agreement on Climate The Paris Agreement is an instrument made under the UNFCCC, The Paris Agreement provides the international framework and
Change (2015) with the central aim of strengthening the global response to the context around Australia’s NDC, which is important to establishing
threat of climate change by keeping the global temperature rise the defined acceptable level of GHG emissions from the Prelude
this century well below 2 degrees Celsius above pre-industrial FLNG.
levels and to pursue efforts to limit the temperature increase
even further to 1.5 degrees Celsius in order to prevent
dangerous human caused interference with the climate system.
It deals with GHG emissions mitigation, adaptation, and finance.
The agreement's language was negotiated by representatives of
196 state parties, including Australia, and adopted by consensus
on 12 December 2015, before entering in to force in late 2016.
Australia has since ratified the Paris Agreement. The Paris
Agreement requires each party to:
• volunteer its own Nationally Determined Contributions
(NDCs), to report against them annually, and improve
them if it is determined that the collective commitment to
NDCs is considered ineffective or insufficient to keep
global temperature increases to less than 2oC below pre-
industrial levels. This allows for variation in emissions
reduction performance according to the development
status of the country; and
• determine, plan, and regularly report on the contribution
that it undertakes to mitigate global warming. No
mechanism forces a country to set a specific emissions
target by a specific date, but each target should go
beyond previously set targets.
Australia has set Nationally Determined Contribution under the
Paris Agreement of 26% to 28% reduction over 2005 levels.
(Source: climatetracker.org – LULUCF means land use, land-use
change, and forestry).
The Intergovernmental Panel on Climate Change (IPCC)
released a report in October 2018 on the 1.5 degrees Celsius

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target; it concluded that global emissions need to reach net zero
around mid-century to give a reasonable chance of limiting
warming to 1.5 degrees Celsius.

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4.0 Shell Environmental Management Framework

4.1 Shell Health, Security, Safety, Environment and Social Performance
Management Framework
Shell, as a subsidiary of Royal Dutch Shell plc, is a member of the Shell group of
companies (and in this EP, where there is reference to Shell’s activities globally, the
term “Shell Group” is used).
The Shell Group operates under a common set of business principles, supported by
policies, standards and business controls which are implemented throughout the
organisation structure. In support of the business principles, there is a Shell Group
HSSE and SP Policy which requires every Shell Company to manage HSSE and SP in
a systematic manner.
The Shell Group HSSE and SP Control Framework is a corporate management
framework which applies to every Shell Group company, contractor and joint venture
under Shell’s operational control.

4.2 HSSE & SP Policy

The Shell Commitment and Policy on HSSE & SP applies across the Shell Group and
is designed to protect people and the environment. The policy, endorsed and adopted
by Shell, is presented in Figure 4-1. The policy illustrates the commitment made by the
senior management and all staff of Shell to achieve not only compliance with
environmental standards set by the Australian Government and the Company, but also
to seek continual improvements in performance.
Key features of the policy are:
• systematic approach to HSSE and SP management designed to ensure compliance
with the law and to achieve continuous performance improvement
• targets for improvement and measurement, appraisal and performance reporting
• requirement for contractors to manage HSSE and SP in line with this policy
• effective engagement with neighbours and impacted communities.

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Figure 4-1: Shell Australia’s HSSE & SP Policy

4.3 HSSE & SP Control Framework

All Shell’s operations are conducted in accordance with Shell’s HSSE & SP Control
Framework, a comprehensive corporate management framework. This Framework
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defines a set of mandatory requirements that define minimum HSSE & SP principles
and expectations, which are documented in a set of manuals. Figure 4-2 outlines the
various control framework manuals applicable to Prelude FLNG.

Figure 4-2: Shell HSSE & SP Control Framework

4.4 HSSE & SP Management System (MS)

The Shell HSSE &SP-MS provides a structured and documented system for the
effective management of impacts and risks and demonstrates how the requirements of
the Shell Group HSSE & SP Control Framework are implemented throughout Shell.
The Shell HSSE & SP-MS Manual consists of the following elements:
• Leadership and Commitment
• Policy and Objectives
• Organisation, Responsibility and Resources, Standard and Documents
• Risk Management
• Planning and Procedures
• Implementation, Monitoring and Reporting
• Assurance, and
• Management Review.

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The HSSE & SP-MS is subject to a continuous improvement ‘plan, do, check, review’
loop, with the eight elements as listed above. There are numerous, specific ongoing
(typically annual) assurance activities against each of the eight elements in the HSSE
& SP-MS Manuals, to ensure that the system is being implemented, is effective and to
identify areas for improvement.
Environmental management for Prelude is through the implementation of the Shell
HSSE & SP-MS, supplemented by facility/asset specific HSSE systems/procedures
(e.g. Shell Permit to Work system and associated procedures such as Confined Space
Entry, Isolations, etc. as appropriately developed at the stage of project
implementation).
Shell implements specific pre- and post-contract award processes and activities aimed
at ensuring that contracts consistently and effectively cover the management of HSSE
& SP risks and deliver effective management of HSSE & SP risks for contracted
activities. Contractor HSSE & SP Management is governed by the Shell HSSE & SP
Control Framework.
As a minimum, all relevant field active contractors’ HSSE & SP-MS will be assessed to
ensure they meet materially equivalent outcomes to Shell’s HSSE & SP-MS.

5.0 Stakeholder Consultation

As titleholder, Shell has consulted with relevant persons in accordance with the
NOPSEMA Decision-making guideline – Criterion-10A(g) Consultation Requirements
(N-04750-GL1721 Rev 6 2019a) and NOPSEMA’s Bulletin #2 (2019c) under the
OPGGS (E) Regulations 2009 for this EP (Document number: 2000-010-G000-GE00-
G00000-HE-5880-00002).
Shell has ensured all Relevant Persons (Table 5-3) have been provided with sufficient
information and had the opportunity to raise any objections or claims.
Shell has addressed objections and claims raised in relation to this EP and can
demonstrate that the risk or impact in question has been reduced to ALARP and to an
acceptable level.

5.1 Background
Consultation and stakeholder engagement for Prelude began when the gas field was
first discovered in early 2007 and has continued since the Final Investment Decision
(FID) was taken in May 2011. This included a thorough consultation process on the
environmental impacts for the Prelude FLNG Project EIS. The project received
environmental approval under the Environment Protection and Biodiversity Act 1999 on
the 12th November 2010 (EPBC 2008/4146). Extensive consultation was subsequently
carried out to support the acceptance of the Prelude Drilling and Completions
Environment Plan (2012), the Prelude Subsea Installation EP (2014) and the Prelude
Installation and Operations Environment Plan (2016).
This consultation overview outlines the approach for the submission of this revised
Prelude EP now that Prelude has moved into production.

5.2 Shell General Business Principles and Stakeholder Engagement

Stakeholder engagement and consultation is an integral part of Shell’s social
performance, impact assessment and project development process, helping to both

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inform business decisions and identify issues that require action. Shell has internal
policies and processes which outline the requirements of stakeholder engagement.
These are underpinned by Shell’s General Business Principles (refer to Section 3.2
Standards and Guidelines), which govern how the Shell companies that make up the
Shell Group conduct their affairs.
Key principles for stakeholder engagement:
• Local communities – Shell aims to be a good neighbour by continuously improving the
ways in which we contribute directly or indirectly to the general wellbeing of the
communities within which we work. We manage the social impacts of our business
activities carefully and work with others to enhance the benefits to local communities,
and to mitigate any negative impacts from our activities. In addition, Shell companies
take a constructive interest in societal matters, directly or indirectly related to our
business.
• Communication and engagement – Shell recognises that regular dialogue and
engagement with our stakeholders is essential. In our interactions with local
communities, we seek to listen and respond to them honestly and responsibly. Part of
this commitment is ensuring those people and organisations that are impacted by our
activities are engaged, and that their concerns are heard and responded to.

5.2.1 Stakeholder Engagement Process

In supporting Shell’s adherence to the Shell general Business Principles is a
comprehensive stakeholder strategy which ensures that:
• the external context is monitored and understood;
• stakeholder needs, interests, concerns and expectations are understood, shared and
outcomes defined;
• there is a clear and direct link between impacts and risks/opportunities;
• stakeholder engagement protocols established and consistent; and
• explicit inclusion of external perspectives in business decisions.

5.2.2 The Team

Shell Australia has a Perth based External and Government Relations (EGR) team,
which includes Social Performance, who facilitate stakeholder and community
engagement in Australia on behalf of the business with support teams in Canberra,
Melbourne and Queensland.
The EGR team manages the interface for the business with external stakeholders such
as; communities, NGOs, Government(s) and the media. Working as an integrated team
allows a ‘whole of Shell view’ to be provided in stakeholder engagements and ensure
stakeholders receive consistent and coordinated information. This is important where,
for example, exploration activities and Crux (Prelude’s primary backfill), have similar
stakeholders to Prelude and therefore require an aligned approach. We call this
grouping East Browse.
An EP specific meeting is held monthly between the relevant HSSE and External
Relations leads which is driven by the EP commitments register.

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5.2.3 Prelude Stakeholder Engagement Plan

The Stakeholder Engagement Plan is an overarching East Browse Engagement Plan.
This includes a stakeholder matrix, an engagement strategy and a feedback
mechanism.
Shell’s approach to stakeholder engagement for Prelude, as is the case for all of
Shell’s assets, has always been “no surprises” which has driven proactive
engagements with a range of stakeholders from an early stage. Shell has developed
long-term working relationships with those who may be impacted by Prelude or who
may have an interest in it.

5.2.4 EP Consultation Strategy

The East Browse Stakeholder Engagement Plan was used to develop a fit for purpose
EP consultation strategy as illustrated in Figure 5-1.
Subject-matter experts were engaged, as needed throughout the process, to inform the
development of the plan and to ensure the EGR Team had sound understanding of the
Prelude environmental risks and mitigations.

Historical
Prelude FLNG Relevent
Data EP
Stakeholder Persons
(previous Consultation
Engagement Identification
engagements Strategy
Strategy Workshop
and EPs)

Figure 5-1: Development of Consultation Strategy

Relevant Persons
Shell has an internal process to identify, prioritise and understand stakeholders. The
process includes the following steps:
1. Identify stakeholders against specific business objectives.
2. Prioritise stakeholders based on stakeholder views/concerns.
3. Analyse value drivers and views on our activities.
4. Define desired shared outcomes.
5. Early engagements with stakeholders to understand views of impacts, risks and opportunities.

This process was used to develop the Prelude FLNG Stakeholder Matrix and formed
the foundation for a Relevant Persons Identification Workshop.
The workshop was attended by EGR representatives as well as Safety and
Environment subject matter experts. During the workshop, each potential stakeholder
was assessed based on how Prelude activities could impact their functions, interests or
activity.
The workshop was informed by:
• historic information gathered as part of the initial Prelude EP submission and Shell
Prelude stakeholder engagement process

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• desktop research to identify the specific functions, interests and activities of each
Relevant Person.
Once stakeholders were identified, Shell determined the most appropriate consultation
approach and associated information to communicate based on the:
• functions, interests and activities of the person;
• prior feedback and information from Relevant Persons on their perspectives and how
they prefer to be engaged gathered as part of the Prelude stakeholder engagement
process; and
• information gathered during prior engagement activities and/or ongoing communication
with stakeholders.

The result was a list of all Relevant Persons who require formal consultation and their
information requirements are shown in Table 5-3. Upon acceptance of this EP, Shell
will uphold its commitments to ensuring Relevant Persons continue to be consulted
throughout the five-year duration of this plan.
Consultation is tailored to the specific functions, interests or activities of the Relevant
Persons. The planned frequency of these consultations for each Relevant Person can
be found in Table 5-3. The frequencies and requirements were identified and discussed
in the Relevant Persons Identification Workshop and updated as feedback was
gathered as part of the consultation process.
The assessment is dynamic and could change, for example changes to scope, in which
case the Prelude FLNG Stakeholder Engagement Plan would be updated. Progress of
planned consultation is tracked and recorded in the Prelude FLNG Stakeholder
Engagement Plan, and it is subject to a half yearly review.
Relevant Persons themselves can and have identified their preferred ongoing
engagements for Prelude. In such cases, that suggestion is considered and if
appropriate, implemented.
Shell’s internal ‘management of change’ process will also ensure that any material
changes to the activity scope will trigger engagement with those who may be impacted.
Relevant Persons will be reviewed as part of the standing agenda for the Prelude EP
Monthly Meeting.
EP Guidance on Consultation
Stakeholder consultation for this activity has also been guided by various stakeholder
organisation expectations for consultation on planned activities. The guidance
consulted included but is not limited to those summarised in Table 5-1.
Table 5-1: Guidance for EP Stakeholder Consultation
Organisation Guidance
NOPSEMA • Consultation with Commonwealth agencies with
responsibilities in the marine area (N-06800-GL1887 2019).
• NOPSEMA Decision-making guideline – Criterion-10A(g)
Consultation Requirements (N-04750-GL1721 rev 6 Nov
2019a)
• Clarifying statutory requirements and good practice
(NOPSEMA Bulletin #2 2019c)

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Australian Fisheries • Petroleum industry consultation with the commercial fishing

Management Authority industry
(AFMA)

Commonwealth • Fisheries and the Environment – Offshore Petroleum and

Department of Greenhouse Gas Act 2006
Agriculture, Water and • Offshore Installations Biosecurity Guide 2019
the Environment (DAWE)
WA Department of • Guidance statement for oil and gas industry consultation with
Primary Industries and the Department of Fisheries 2013
Regional Development
(DPIRD)
WA Department of • Offshore Petroleum Industry Guidance Note July 2020
Transport (DOT)

Reasonable Period
Shell determined that a minimum of 30 days is a reasonable period for formal
consultation. This is a common duration specified for matters that are open to public
comment and Shell’s historic engagements supports that it is sufficient time to allow for
a Relevant Person to assess the information provided by Shell in a letter containing all
the risks as outlined in the EP and respond detailing any claims or objections.
The 30-day period acts as a minimum period in Shell’s consultation planning
processes, and Relevant Persons are explicitly asked to respond within that time.
However, Shell acts on a case-by-case basis depending on the response received from
Relevant Persons and will allow for requests to extend this period, if requested. Shell
will also follow up within that 30-day period if no response is received, where contact
details are available.
As part of the review, it was identified that a reasonable period needed to be defined
for ongoing consultation. Table 5-2 outlines Shell’s approach.

Table 5-2: Reasonable Period for Ongoing Consultation

Type of Consultation Timing

New, formal consultation
The 30-day period acts as a minimum period in the consultation planning 30 days
process for new information distributed to Relevant Persons.
Ongoing consultation
The 14-day period acts as a minimum period to respond to claims or objections 14 days
received once in the ongoing consultation phase.
This will be managed on a case-by-case basis so that timeframes will take into
account other factors (such as how much correspondence there has been with
the Relevant Person, the merits of the claim or objection and/or the complexity of
the claim or objection).

Sufficient Information
When carrying out consultation with Relevant Persons, Shell considers the potential
impacts of Prelude activities on the particular functions, interests and activities of each

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Relevant Person to ensure that sufficient and appropriate information is provided. In

summary, EP submission consultation involved the following:
Letter and accompanying factsheet
Shell provided Relevant Persons with a letter and accompanying information sheet
outlining all the risks and mitigations extracted directly from the EP. This approach
ensured that recipients had access to the impacts and risks outlined in the EP and the
associated mitigations; and could make their own assessment on the impact of the
activity. Therefore, removing potential for Shell to make any assumptions about what
Relevant Persons would be interested or concerned about.
The factsheet also contained contact details, location specifics, details of the activity
and the response period of 30 days (Appendix A: Detailed Facility Description), a link to
the Prelude microsite and a link to the full draft EP, for those seeking more detailed
information.
The letter and/or cover email was tailored to meet the needs of different Relevant
Persons as determined by the Relevant Persons Identification workshop. For example,
for Commercial Fishers who can only be contacted by mail.
Shell believes that this letter and factsheet, access to the full draft EP and the follow up
process provided Relevant Persons with sufficient information to be able to consider
the impacts on their functions, interests and activities.
Face-to-Face Meetings
In most cases, engagement for the EP did not require a face-to-face meeting and the
majority of Relevant Persons did not wish to meet with Shell. However, in some cases
where a Relevant Person showed considerable interest in the EP activities, face-to-
face meetings were arranged to engage and share information. This also allowed
access to and engagement with Shell subject-matter experts.
Prelude Website
Shell prepared a website outlining the content of the EP in digestible format for the
general public. This website forms the basis for consultation, allowing stakeholders to
select the information which interests them most. Once the EP is published on
NOPSEMA’s website, the Prelude website will provide a link to the EP submission for
those that want more detailed information.

5.2.5 Assessment of merits of claims and objections

Shell has a claims process which guides our actions in response to claims and
objections received from stakeholders related to Prelude. This process is included in
Appendix A: Detailed Facility Description.
Claims received are processed through Shell’s global system – Insight Browser.
Identified Claims or Objections are tracked within this system. Failure to close out
complaints in the system results in escalation to senior management and risks a
breach of Shell’s social performance standards.
Shell has adhered to NOPSEMA’s guidance (N-04750-GL1721 Rev 6 2019a) in
relation to the definitions of claims and objections, where an ‘objection or claim’ is
taken to mean:
• To express opposition, protect, concern or complaint about the proposed activities; a
request or demand that certain action be taken by the titleholder to address adverse
impacts; and

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• An assertion that there will be an adverse impact; or allegation to cast doubt about the
manner in which the activities will be managed.”

5.2.6 Summary of Consultation

A summary of consultation activities undertaken, and the Relevant Persons consulted
during the development of this EP are presented in Table 5-3 and Table 5-4. An
assessment of merit was undertaken and is presented in Table 5-5.

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Table 5-3: Assessment of Relevant Persons for the Activity

Stakeholder Stakeholder Relevant Relevance (Functions, Interests or Activities) Frequency of Ongoing Consultation
ID to
activity

WA State and Commonwealth

• As required through EP
RP01 Australian Border Force (ABF) Yes Maintains the integrity of Australia’s international borders including
change assessments; or
customs and immigration.
• When major non-standard
activities arise which may
RP02 Australian Hydrographic Service Yes The RAN Australian Hydrographic Service is the Commonwealth directly affect the functions,
(Department of Defence) Government agency responsible for the publication and distribution of interests or activities of the
nautical charts and other information required for the safety of ships relevant person.
navigating in Australian waters.
Issue notice to mariners and update nautical charts.

RP03 Department of Agriculture, Water Yes Biosecurity regulator and responsible for Australia-Indonesia
and the Environment (DAWE) Memorandum of Understanding regarding the Operations of Indonesian
Traditional Fishermen in Areas of the Australian Fishing Zone and
Continental Shelf – 1974.

RP04 Department of the Environment and Yes Administers the EPBC Act. Main functions are associated with providing
Energy (DEE) oiled wildlife advice in commonwealth waters during an Oil spill.

RP05 Department of Foreign Affairs and Yes International relations with governments and other organisations.
Trade (DFAT) Specifically, DFAT will have functions relating to oil spills in international
waters or foreign countries jurisdictions.

RP06 Parks Australia (PA) Yes Parks Australia looks after Australia’s natural treasures – including
Kakadu, Uluru and our beautiful oceans. They are responsible for six
national parks, 58 marine parks and the Australian National Botanic
Gardens.

RP07 Australian Marine Safety Authority Yes Statutory agency for vessel safety and navigation and legislated
(AMSA) including AMSA RCC. responsibility for oil pollution response in Commonwealth Waters.

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Stakeholder Stakeholder Relevant Relevance (Functions, Interests or Activities) Frequency of Ongoing Consultation
ID to
activity

RP08 Department of Water & Yes Responsible for implementing Commonwealth policies and programs to
Environmental Regulation (DWER) support the agriculture, fisheries, food and forestry industries.

RP09 WA Department of Mines, Industry Yes Required to be consulted under the Regulations.
Regulation & Safety (DMIRS)

RP10 WA Department of Primary Yes Responsible for managing State fisheries.

Industries and Regional
Development - Fisheries Division
(DPIRD)

RP11 Department of Primary Industry and Yes Responsible for managing Territory fisheries.
Resources NT (DPIR)

RP12 WA Department of Biodiversity, Yes Responsible for managing WA’s parks, forests and reserves. Planned
Conservation & Attractions (DBCA) activities do not impact DBCA’s functions, interests or activities.

RP13 WA Department of Transport (DOT) Yes Legislated responsibility for oil pollution response in State Waters.

RP75 Director of National Parks Yes The Director of National Parks is the statutory authority responsible for
administration, management and control of Commonwealth marine
reserves.

RP76 Clean Energy Regulator (CER) Yes Responsible for the administration of schemes legislated by the
Australian Government for measuring, managing, reducing or offsetting
Australia's GHG emissions.

Northern Territory
• As required through EP
RP77 NT Department of Environment and Yes Responsible for marine pollution control in NT waters.
change assessments; or
Natural Resources

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Stakeholder Stakeholder Relevant Relevance (Functions, Interests or Activities) Frequency of Ongoing Consultation
ID to
activity
• When major non-standard
RP78 NT Department of Infrastructure, Yes Responsible for marine safety in NT waters.
activities arise which may
Planning and Logistics – Marine
directly affect the functions,
Safety Branch
interests or activities of the
relevant person.
Commonwealth Fisheries
• As required through EP
RP14 Australian Fishery Management Yes The AFMA is the Australian Government agency responsible for the
change assessments; or
Authority (AFMA) efficient management and sustainable use of Commonwealth fish
• When major non-standard
resources, in particular, Section 7 of the Fisheries Administration Act
activities arise which may
1991.
directly affect the functions,
interests or activities of the
RP15 – RP22 North West Slope Trawl Fishery Yes Activities exist in or in close proximity to Prelude. Bottom trawl. relevant person.
License Holders

RP23 Southern Bluefin Tuna Fishery Yes The Southern Bluefin Tuna Fishery covers the entire sea area around
Australia, out to 200 nm from the coast. Pelagic long line and purse
seine fishing gear is used.

RP24 Western Tuna & Billfish Fishery Yes Activities exist in or in close proximity to Prelude. Near surface longline
and minor line gear used.

Recreational Fisheries
• Not required
RP25 RecFishWest No Shell contacted RecFishWest and they have confirmed that no fishing is
undertaken as far offshore as Prelude, and therefore they are not
relevant.

WA State Fisheries
• As required through EP
RP30 – RP56 Mackerel Managed Fishery License Yes Activities exist in or in close proximity to Prelude. Near-surface trawling
change assessments; or
Holders activities near coastal areas primarily.

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ID to
activity
• When major non-standard
RP57 – RP59 North Coast Shark Fishery License Yes Activities exist in or in close proximity to Prelude. Primarily use
activities arise which may
Holders demersal gillnets and longlines.
directly affect the functions,
interests or activities of the
RP60 – RP67 Northern Demersal Scalefish Yes The only known active fishery that overlaps the operational area - relevant person.
Fishery License Holders primarily trap based fishery.

RP68 Pearl Producers Association (PPA) Yes Peak industry representative body for the Pinctada maxima pearling
industry licensees in Western Australia. Activities exist in or in close
proximity to Prelude. Bottom drifting divers from Lacepede Islands
south to Exmouth.

RP69 – RP71 West Coast Deep Sea Fishery Yes Activities exist in or in close proximity to Prelude. Baited pots >150m
License Holders water depth, mostly between 500 – 800 m.

RP72 Western Australian Fishing Industry Yes Represents the interests of commercial fishers with licences in the WA
Council (WAFIC) State Managed Fishery.

Industry
• As required through EP
RP73 INPEX Yes Adjacent titleholder; operator of WA-532-P and AC/P36
change assessments; or
• When major non-standard
RP74 Finder No 13 Pty Ltd Yes Adjacent titleholder; operator of AC/P55 activities arise which may
directly affect the functions,
interests or activities of the
relevant person.

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Table 5-4: Stakeholder Consultation Activities During Development of EP

Stakeholder Stakeholder Date Method Consultation Activities
ID

WA State and Commonwealth

RP01 Australian Border Force (ABF) 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

09 December 2019 Phone call Followed up with a phone call.

09 December 2019 Email Email received closing out consultation.

RP02 Australian Hydrographic Service 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
(Department of Defence) microsite and full draft EP.

19 November 2019 Email Email received closing out consultation.

RP03 Department of Agriculture, Water and 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
the Environment (DAWE) microsite and full draft EP.

10 December 2019 Email Followed up with an email.

11 December 2019 Email Email response sent to the Department.

11 December 2019 Email Email response received from the Department - they are reviewing the
documentation at the moment and will provide a departmental coordinated
response.

12 December 2019 Email Email to the Department on MOU Box (74).

18 December 2019 Conference call Conference call arranged to discuss feedback and to walkthrough materials
sent and clarify any questions from the Department.

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ID

20 December 2019 Email Email received from the Department confirming the biosecurity controls in the
EP is consistent with their expectations keeping in mind that there will be new
policy coming out on which Shell will be consulted

RP04 Department of the Environment and 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Energy (DEE) microsite and full draft EP.

19 December 2019 Phone call Follow up phone call.

19 December 2019 Email Follow up email.

3 February 2020 Email Follow-up email. Email response received from the Department saying as
NOPSEMA is the regulating agency for this matter, the Department of
Environment has no feedback on the plan.

RP05 Department of Foreign Affairs and 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Trade (DFAT) microsite and full draft EP.

18 December 2019 Phone call Follow up phone call.

18 December 2019 Email Follow up email sent.

RP06 Parks Australia 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

25 November 2019 Email Email received with request for further information.

02 December 2019 Email Map provided with coordinates and location relative to marine parks as
requested.

RP07 Australian Marine Safety Authority 2 October 2019 Email Initial email sent to AMSA to confirm if ‘relevant person’.

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ID
(AMSA) including AMSA RCC.
19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

03 February 2020 Email Follow up email to AMSA.

09 June 2020 Email Email to AMSA to request follow up discussion (following Shell’s initial
submission on Marine Order 47 consultation process in May 2020) specific to
Prelude and the application of Marine Order 90 series.

11 June 2020 Meeting Virtual meeting to discuss application of Marine Order 90 series to Prelude.

29 July 2020 Emailed letter Mailed follow-up letter from meeting on 11th June 2020. Outlined Shell’s
position regarding compliance with Marine Order 90 series.

13 August 2020 Email Follow up email sent to AMSA to check status of letter response on Marine
Order 90 series.

13 August 2020 Email Email from AMSA confirming finalisation of reply to Shell.

24 August 2020 Email Further follow up email to AMSA.

26 August 2020 Email Email from AMSA confirming imminent formal letter response to Shell’s letter
of 29 July 2020.

27 August 2020 Emailed Letter AMSA sent a letter responding to engagement with Shell and subsequent
letter from Shell to AMSA sent on 29 July 2020.

RP14 Australian Fishery Management 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Authority (AFMA) microsite and full draft EP.

17 December 2019 Email Follow up email.

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ID

RP08 Department of Water & Environmental 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Regulation (DWER) microsite and full draft EP.

19 December 2019 Phone call Follow up call provided. Requested to send through material again to generic
mailbox.

20 December 2019 Email Info resent to requested inbox.

RP09 Department of Mines, Industry 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Regulation & Safety (DMIRS) microsite and full draft EP.

16 December 2019 Email Email received closing out consultation.

RP10 Department of Primary Industries and 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Regional Development - Fisheries microsite and full draft EP.
Division (DPIRD)
06 December 2019 Phone call Phone call to discuss query regarding fish cube data and to test Shell’s
analysis.

06 December 2019 Email Email to DPIRD regarding clarification of fish cube data.

18 December 2019 Phone call Follow up phone call, information has been received and will be reviewed in
early 2020.

19 December 2019 Email Email from DPIRD confirming fish cube data information.

9 January 2020 Phone call Follow up call, left voice message.

14 January 2020 Phone call Follow up call, DPIRD confirmed response will be received by end of the
week.

17 January 2020 Email Email received from DPIRD with feedback and comments.

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ID

31 January 2020 Email Email response to DPIRD’s comments.

RP11 Department of Primary Industry and 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Resources NT microsite and full draft EP.

18 December 2019 Phone call Attempted follow up phone call to two contacts at the department with no
response.

18 December 2019 Email Follow up email sent.

RP12 WA Department of Biodiversity, 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Conservation & Attractions (DBCA) microsite and full draft EP.

18 December 2019 Email Follow up email sent.

18 December 2019 Email Email received - automatic out of office reply.

19 December 2019 Email Email received closing out consultation.

20 December 2019 Email Email to close out consultation process.

RP13 WA Department of Transport (DOT) 01 October 2019 Email Sent Draft OPEP provided for comment with supporting DOT industry
guidance note information.

07 November 2019 Email Received from DoT with clarifications and comments on the draft OPEP

19 November 2019 Email Sent Info provided on proposed activity with information sheet, link to Prelude
EP microsite and full draft EP.

27 November 2019 Email Sent response to DOT comments/clarifications on the draft OPEP provided.

19 December 2019 Email Received asking two clarifications.

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ID

20 December 2019 Email Sent response to DOT comments/clarifications.

07 January 2020 Email Received from DOT asking question about spill modelling result sent.

09 January 2020 Email Sent response to DOT answering the question regarding spill modelling.

21 January 2020 Email Received from DOT stating no more questions on the content provided.

RP75 Director of National Parks 19 December 2019 Email Sent information on proposed activity with information sheet, link to Prelude
EP microsite and full draft EP, including marine parks map.

19 December 2019 Email Received confirmation that planned activities do not overlap any Australian
Marine Parks and no authorisation requirements from the DNP are required.
Noted emergency response notification process to DNP if there are
emergency oil/gas pollution incidents which occur within a marine park or are
likely to impact on a marine park.

31 January 2020 Email Email to confirm consultation process closed.

RP76 Clean Energy Regulator (CER) 19 May 2020 Email Email exchanges with the CER to request a meeting to discuss the Prelude
EP.

19 May 2020 Email Email from the CER confirming suggested meeting dates.

27 May 2020 Meeting Virtual meeting with CER to provide latest information on forecasts for Prelude
FLNG and to discuss potential options regarding revision to the Prelude
safeguard mechanism baseline through a transitional calculated baseline.

11 June 2020 Email Meeting minutes and supporting information regarding Prelude FLNG
provided following the virtual meeting on 27 May 2020.

Northern Territory

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ID

RP77 Department of Environment and 15 June 2020 Email Info provided on proposed activity with information sheet, link to Prelude EP
Natural Resources (NT DENR) microsite and full draft EP.

07 July 2020 Email Follow up email to the NT DENR.

10 July 2020 Emailed letter Emailed letter received form the NT DENR to Shell Australia confirming
details to include in the Prelude emergency contingency plans.

31 July 2020 Email Email sent to NT DENR confirming receipt of letter and actions. Also
confirmed consultation process is closed.

RP78 NT Department of Infrastructure, 10 July 2020 Email A copy of the Shell Australia email sent to the NT Department of Environment
Planning and Logistics – Marine Safety and Natural Resources was forwarded internally to the NT Department of
Branch Infrastructure, Planning and Logistics – Marine Safety Branch.

31 July 2020 Email Email to the NT Department of Infrastructure, Planning and Logistics – Marine
Safety Branch to follow up on the email sent by the NT DENR, to check if the
Department has any claims, queries or objections.

24 August 2020 Email Further follow up email to the NT Department of Infrastructure, Planning and
Logistics – Marine Safety Branch to check if the Department has any claims,
queries or objections.

Commonwealth Fisheries

RP15 – RP22 North West Slope Trawl Fishery 19 November 2019 Mailed letter Info provided on proposed activity with information sheet, link to Prelude EP
License Holders microsite and full draft EP.

RP23 Southern Bluefin Tuna Fishery 19 November 2019 Mailed letter Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

RP24 Western Tuna & Billfish Fishery 19 November 2019 Mailed letter Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

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ID

WA State Fisheries

RP26 – RP56 Mackerel Managed Fishery License 19 November 2019 Mailed letter Info provided on proposed activity with information sheet, link to Prelude EP
Holders microsite and full draft EP.

RP57 – RP59 North Coast Shark Fishery License 19 November 2019 Mailed letter Info provided on proposed activity with information sheet, link to Prelude EP
Holders microsite and full draft EP.

RP60 – RP67 Northern Demersal Scalefish Fishery 19 November 2019 Mailed letter Info provided on proposed activity with information sheet, link to Prelude EP
License Holders microsite and full draft EP.

09 December 2019 Email Bespoke information on the risks and impacts to the Northern Demersal
Scalefish Fishery provided.

09 December 2019 Email Email received closing out consultation.

RP68 Pearl Producers Association (PPA) 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

11 December 2019 Phone call Follow up phone call – unavailable.

RP69 – RP71 West Coast Deep Sea Fishery License 19 November 2019 Mailed letter Info provided on proposed activity with information sheet, link to Prelude EP
Holders microsite and full draft EP.

RP72 Western Australian Fishing Industry 19 November 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
Council (WAFIC) microsite and full draft EP.

19 November 2019 Email Email received from WAFIC requesting more bespoke information

21 November 2019 Email Email sent to WAFIC with more specific links to relevant information.

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ID

21 November 2019 Email Email received from WAFIC.

25 November 2019 Email Response sent to WAFIC with clarification on Prelude resubmission and map
of Operational Area.

26 November 2019 Email Email received from WAFIC.

06 December 2019 Email Response sent to WAFIC.

19 December 2019 Email Email received from WAFIC closing out consultation.

Industry

RP73 INPEX 13 December 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

RP74 Finder No 13 Pty Ltd 13 December 2019 Email Info provided on proposed activity with information sheet, link to Prelude EP
microsite and full draft EP.

Table 5-5: Stakeholder Claims and Objections – Assessment of Merit

Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims

WA State, Northern Territory and Commonwealth

RP01 Australian Border 9 December 2019 Email received to say the ATT Delegate has No claim or objection received. Not applicable
Force (ABF) not advised of any comments.

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ID Claims or Objections to Objections and Claims

RP02 Australian 5 November 2019 Email received to say that the Australian No claim or objection received. Not applicable
Hydrographic Hydrographic Office have everything they
Service 19 November 2019 need.
(Department of
Defence)
Phone conference between Shell and the
RP03 Department of 18 December 2019 Department. The Department indicated that No claim or objection received. Not applicable
Agriculture, Water there will be a new mandatory biofouling
and the 20 December 2019
management
Environment policy coming out in the new year, following
(DAWE) from a consultation process. This will include
alignment with new IMO standards, specific
biofouling plans for vessels and contingency
measures within those plans.
Email received from the Department
confirming the biosecurity controls in the EP is
consistent with their expectations keeping in
mind that there will be new policy coming out
on which Shell will be consulted.

RP04 Department of the 19 November 2019 Response received 3 February 2020 advising No claim or objection received. Not applicable
Environment and that as NOPSEMA is the regulating agency for
Energy (DEE) 19 December 2019 this matter, the Department has no feedback
3 February 2020 on the plan.

RP05 Department of 18 December 2019 Email received to confirm that DFAT cannot No claim or objection received. Not applicable
Foreign Affairs and provide advice on the environmental approval
Trade (DFAT) processes as this matter does not fall within
the remit of DFAT’s policy responsibilities.
Follow up phone call with DFAT Deputy
Director (WA office), who confirmed that DFAT
does not take a position on this type of
consultation, so this closes out the

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ID Claims or Objections to Objections and Claims
consultation process with DFAT and no further
action is required.

RP06 Parks Australia (PA) 25 November 2019 Guidance material developed by NOPSEMA in No claim or objection received. Not applicable
consultation with the Director of National Parks
20 December 2019 (DNP) requires that titleholders provide a
description of the operational area including a
map showing location of the activity relative to
marine park boundaries. Relevant shapefiles
for mapping are available at:
https://parksaustralia.gov.au/marine/maps/
Stakeholder requested a map showing the
distance to the mainland with coordinates
showing Prelude location relative to marine
parks.

RP07 Australian Marine 19 November 2019 No response received No claim or objection received. Not applicable
Safety Authority
(AMSA) including 3 February 2020
AMSA RCC.
11 June 2020 Clarification was sought from AMSA on the Shell notes the Marine Order 90 On 19 November 2020, Shell
applicability of the Marine Orders 90 series to series apply to Prelude as responded to AMSA’s letter dated
29 July 2020 the Prelude FLNG. enacted through the POTS 27 August 2020, confirming that
27 August 2020 (PPS and AFS) legislation. Shell will comply with the Marine
AMSA responded to Shell’s letter suggesting Shell will comply with these Order 90 series as they apply to
that the Marine Order 90 series and legislated requirements as the Prelude FLNG. In addition,
associated POTS (PPS) Act do apply to the required. This was considered a Shell confirmed that engagement
Prelude FLNG including certifications for relevant matter for the EP. will occur with the Recognised
relevant systems which were in place when Organisation on the detailed
Prelude arrived on location. AMSA suggested As AMSA suggested, Shell will matters relating to the
Lloyd’s Register would be the appropriate engage with Lloyd Register on implementation of Marine Order
body to follow-up with on the detailed aspects implementation of relevant 90 series to Prelude FLNG.
of compliance with various aspects of Marine Marine Order 90 series.
Order 90 series and associated POTS (PPS) Shell has made relevant updates
(AFS) Act. The following summarises the Changes to reflect this have within the EP to ensure the
been made in the relevant

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ID Claims or Objections to Objections and Claims
advice provided by AMSA in its letter dated 27 Marine Order 90 series controls requirements outlined by AMSA
August 2020: outlined in section 9.0. on 27 August 2020 are accurately
reflected within the EP. In addition,
MO 91 – sets out the requirements for the Shell will engage with the
prevention of pollution by oil. MO 91 gives Recognised Organisation, Lloyd’s
effect to MARPOL Annex 1, of which Register.
regulation 1 defines the term “oil” and includes
the substances listed in appendix 1 and Annex
I. These substances include casing head
(natural) and condensate, both of which AMSA
understands are present on board Prelude. In
considering the above, MARPOL Annex I,
Regulation 39 special requirements for fixed
and floating platforms will apply to Prelude.
AMSA also suggests that Shell explore the
application of IMO resolution MEPC.139(53)-
Guidelines for the application of the revised
MARPOL Annex I requirements to FPSO
facilities and FSU's, as amended by resolution
MEPC.142 (54), as referenced in this
regulation. The list of compliance requirements
is contained within the referenced Guidelines.
MO 93 – AMSA notes that MO 93 does not
apply to Prelude as it is not designed to carry
Noxious Liquid substances in bulk form.
Considering the various products associated
with Prelude’s operations, and the quantities
stored onboard, AMSA suggest that Shell
discuss applicability of MO 93 with recognised
organisation
MO 94 - sets out the requirement for
preventing packaged harmful substances from
polluting the marine environment. MO 94 gives
effect to Annex III of MARPOL and prescribed
matters relating to Part IIIA of POTS (PPS).

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ID Claims or Objections to Objections and Claims
AMSA suggests that Shell seek the
Recognised Organisation’s view on the
systems and procedures necessary to ensure
obligations under the above Part IIIA, as
implemented by MO 94, are complied with.
MO 95 - sets out requirement for prevention of
pollution by garbage from ships. MO95 gives
effect to MARPOL Annex V and prescribes
matters relating to POTS (PPS). Annex V
requires Prelude keep a garbage record book.
AMSA may waive the requirement to maintain
a garbage record book, under Reg. 10(4)(2),
however AMSA has no record of having
received or issued to Prelude a waiver in
relation to the Garbage Record Book.
MO 96 – sets out the requirement for the
prevention marine pollution by sewage from
the ships and effects MARPOL Annex IV –
Sewage. Matters are addressed in Part IIIB
Div. 2 of POTS (PPS). Prelude is required to
demonstrate and maintain compliance with
these regulations.
MO 97 - sets out the requirements for the
prevention of air pollution by ships and gives
effect to MARPOL Annex VI- Air. Matters are
addressed in Part IIID of POTS (PPS). AMSA
notes that MARPOL ANNEX VI Regs. 13 does
not appear to have been addressed in the
letter.
MO98 – sets out the requirements for anti-
fouling and their certification and gives effect
to the anti-fouling certification requirement of
POTS (AFS). AMSA notes that Lloyd’s

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ID Claims or Objections to Objections and Claims
Register has issued International Anti-Fouling
System Certificate – 1425-LR KOJ 1200001
dated 28 June 2017, for the purpose of MO98.

RP14 Australian Fishery No response received No claim or objection received. Not applicable
Management
Authority (AFMA)

RP08 WA Department of No response received No claim or objection received. Not applicable

Water &
Environmental
Regulation (DAWR)

RP09 WA Department of 13 December 2019 Email received to say that no further No claim or objection received. Not applicable
Mines, Industry information is required at this stage.
Regulation & Safety
(DMIRS)

RP10 WA Department of 06 December 2019 Email to DPIRD regarding Fish Cube data The suggestion of including Shell has reviewed the draft
Primary Industries clarification. “Administrative and Procedural Biosecurity Reference Case
and Regional controls” for supporting vessels (Maritime Industry Australia Ltd,
Development 18 December 2019 which aligns with proposed 2020) and ensured controls
(DPIRD)- Fisheries Phone call to DPIRD. DPIRD to confirm fish “NOPSEMA Offshore Support described in Section 9.8.5 of the
Division cube data information in a follow up email and Vessel Reference Case” EP are consistent with the
will respond formally with any specific EP process is considered to be a reference case.
comments in early 2020. relevant matter and the EP has
been updated to reflect.
19 December 2019
DPIRD provided Shell with some clarification IMO biofouling guidelines Supporting vessels attending site
on Fish Cube data.” Less than three vessels” considered ‘best practice’ for will meet IMO biofouling
does not constitute no fishing activity. Fish mitigation of transfer of invasive guidelines.
cube data differentiates between “less than 3 aquatic species to ALARP is
vessels” and “no fishing activity” for each considered to be a relevant
block.” matter and the EP has been
updated to reflect.

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Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims
Supporting vessels attending site
DPIRD noted Shell committed (to WAFIC) to The suggestion that supporting will have a BMP and BRB.
develop more bespoke material for the vessels are encouraged to have
Northern Demersal Scalefish Fishery (NDSF) vessel specific (as per IMO
and set out specific information regarding guidance) Biofouling
impacts on fishing and fisheries activities Management Plan (BMP) and
related to Prelude activities. Biofouling Record Book (BRB)
recording implementation of
BMP is considered to be a
DPIRD had some additional minor comments relevant matter and the EP has
on the draft prelude EP: been updated to reflect this..

Application of an Antifoulant
• The BAM Act 2007 is not mentioned coating is only one mitigation
17 January 2020 in Table 5-3: Prelude FLNG action, of a ‘best practice’ IMO
Environment Plan Relevant Persons biofouling guidance approach.
and Consultation Process Shell acknowledged this claim.
• Typo in Table 5-3 relating to DPIRD However, no update to the EP
entry “They administer the Fish is proposed.
Resources Management Act 1984”
• Table 9-33: ALARP evaluation of IMS
risk control measures
o Suggest “Administrative and
Procedural controls” for
supporting vessels which
aligns with proposed
“NOPSEMA Offshore
Support Vessel Reference
Case” process. IMO
biofouling guidelines
considered ‘best practice’ for
mitigation of transfer of
invasive aquatic species to
ALARP. Suggest supporting
vessels encouraged to have

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Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims
vessel specific (as per IMO
guidance) Biofouling
Management Plan (BMP)
and Biofouling Record Book
(BRB) recording
implementation of BMP.
Application of an Antifoulant
coating is only one
mitigation action, of a ‘best
practice’ IMO biofouling
guidance approach.
• DPIRD clarified contact information
required in draft Prelude EP.
DPIRD requested clarification on a statement
in draft EP (page 224) “Low Risk Biosecurity
Status Letter from the Department of
Agriculture and Water Resources (DAWR).”
The clarification related to the statement
applying only the Prelude FLNG topside.

RP11 Department of No response received No claim or objection received. Not applicable

Primary Industry
and Resources NT

RP12 WA Department of 19 December 2019 Email received requesting we provide future No claim or objection received. Not applicable
Biodiversity, notifications to EMBAdmin@dbca.wa.gov.au.
Conservation &
Attractions

RP13 WA Department of 07 November 2019 Requested clarification on reasoning for Changes to worst case spill Shell confirmed the justification for
Transport (DOT) changes in worst credible spill scenarios. volumes were noted between changes to the worst credible spill
19 November 2019 the current EP/OPEP and the scenarios presented in the
Requested to correct some incorrect previous revisions reviewed by EP/OPEP. Section 9.13.1 of the
19 December 2019 references related to the DOT IGN. DOT. This was considered a EP has been updated.

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Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims
07 January 2020 Clarification requested around some roles and relevant matter and the EP has Updates to the consultation
responsibilities. been updated to reflect. materials provided to DOT were
21 January 2020 made to the ensure the correct
Requested information of modelling outputs. Outdated references to the references for the most recent
DOT IGN suggested an older version of the DOT IGN.
Clarification requested around the basis for version may have been used.
worst predicted waste volumes from shoreline This was not considered a Further details were also provided
contact. relevant matter resulting in an on the roles and responsibilities,
Detail of cost recovery arrangements update to the EP. modelling outputs & information,
requested. potential volumes of oil on
shorelines and cost recovery
Clarification requested on limitations around arrangements.
scientific monitoring.
Details on scientific monitoring of
Clarification requested on dispersant types to marine megafauna, proposed
be used. dispersant types and training
More information requested on training requirements of responders were
requirements of responders. also provided.

Request for modelling information

Clarification on modelling information provided
No further question from DoT at this time.

RP75 Director of National 20 December 2019 Email received confirming that planned No claim or objection received. The EP includes confirmation that
Parks activities do not overlap any Australian Marine Shell’s emergency response
Parks and no authorisation requirements from arrangements include relevant
the DNP are required. details and meet notification
requirements.
Noted emergency response notification
process to DNP if there are emergency oil/gas
pollution incidents which occur within a marine
park or are likely to impact on a marine park.

RP76 Clean Energy 27 May 2020 A forecast of future Prelude FLNG GHG No claim or objection received. No changes were made to the EP
Regulator (CER) emissions were shared with the CER based on as a result of this consultation.
Operating Plan (OP) 2019 figures. Shell asked

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Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims
11 June 2020 CER if they could comment on Prelude’s
forecast GHG emissions being of an
“acceptable level of impact”. CER could not
comment on acceptability of forecast Prelude
FLNG emissions, but referred to excess GHG
emissions above the baseline requiring the
acquisition of ACCU’s to offset any
exceedance.
CER asked if forecasts provided were based
on a calendar or financial year basis. Shell
confirmed the information presented was
based on a calendar year.
CER requested a copy of the fact sheet
provided to other Relevant Persons for the
purposes of consultation in preparation of the
Environment Plan.

RP77 NT Department of 10 July 2020 Letter response detailed a requirement for The information received was Requested notification details
Environment and Shell to include the following information in the considered to be a relevant have been included in the OPEP
Natural Resources emergency contingency plans: matter and the OPEP updated Table 4-1 External Notifications
to reflect. and Reporting.
Initial point of contact for spills to NT coastal
waters
Email addresses for POLREPs
Timeframe for notifications to be made (within
24 hours of titleholder becoming aware of an
incident that could occur in NT coastal waters)
Stakeholder consultation materials also sent to
Marine Safety Branch of the NT Department of
Infrastructure, Planning & Logistics.

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Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims

RP78 NT Department of 31 July 2020 Auto response email received stating that No claim or objection received. No changes were made to the EP
Infrastructure, AMSA provides service delivery for owners, as a result of this consultation.
Planning & 24 August 2020 operators and crew of domestic commercial
Logistics- Marine vessels and that waterways management
Safety Branch queries will be responded to within 5 days. No
further response received.

Commonwealth Fisheries

RP15 – North West Slope No response received No claim or objection received. Not applicable
RP22 Trawl Fishery
License Holders

RP23 Southern Bluefin No response received No claim or objection received. Not applicable
Tuna Fishery

RP24 Western Tuna & No response received No claim or objection received. Not applicable
Billfish Fishery

WA State Fisheries

RP30 – Mackerel Managed No response received No claim or objection received. Not applicable
RP56 Fishery License
Holders

RP57 – North Coast Shark No response received No claim or objection received. Not applicable
RP59 Fishery License
Holders

RP60 – Northern Demersal 09 December 2019 Email received from one license holder to say No claim or objection received. Not applicable
RP67 Scalefish Fishery that the assumptions are reasonable.
License Holders

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Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims

RP68 Pearl Producers No response received No claim or objection received. Not applicable
Association (PPA)

RP69 – West Coast Deep 09 December 2019 Email received from one license holder to No claim or objection received. Not applicable
RP71 Sea Fishery License explain what they do. No further comments
Holders noted.

RP72 Western Australian 19 November 2019 WAFIC notes that by and large for almost all No claim or objection received. Not applicable
Fishing Industry EPs that the commercial fishing sector is the
Council (WAFIC) 21 November 2019 only “relevant potentially affected party” to
26 November 2019 operations as described in an EP.
19 December 2019 The information you have sent above
regarding the revised and updated Prelude EP
is not specific enough to potentially affected
commercial fisheries. Please revert with the
bespoke information, appropriate and relevant
for a potentially affected party.
Appreciate that for Prelude the key
commercial fishing stakeholders are licence
holders in the Northern Demersal Scalefish
Fishery. You have noted that there is low
fishing effort – please clarify what you mean
by “low”.
Many thanks for the bespoke updated
information, thank you also for on sending to
NDSF fishers.

Industry

RP73 INPEX No response received No claim or objection received. Not applicable

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Stakeholder Stakeholder Dates Summary of Each Stakeholder Response Assessment of Merit of Summary of Shell’s Response
ID Claims or Objections to Objections and Claims

RP74 Finder No 13 Pty No response received No claim or objection received. Not applicable
Ltd

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5.2.7 Ongoing Consultation

Shell will uphold its commitments to ensuring relevant authorities, persons and
organisations continue to be consulted throughout the five-year duration of this EP
through a number of activities detailed in Table 5-6. Consultations will be tailored to the
specific functions, interests or activities of the stakeholders. This ongoing consultation is
used to inform stakeholders on specific activity timing, duration, location and other
information relevant to the activity and stakeholder needs.

Table 5-6: Ongoing Consultation Activities

Activity Description
Monthly Meeting Implemented Monthly meeting attended by HSSE and EGR
representatives to track and assess consultation and EP
compliance, manage requests for information and the
assessment of merit of any claims and objections. Set
agenda with actions tracked in Commitments Register.
Updated Commitments Register Lists Relevant Persons, details consultation
commitments as per EP Consultation Strategy and
tracks consultation, and outlines EP compliance actions.
Holds actions from monthly meetings.
Ongoing Consultation Procedure Details the procedure of ongoing consultation with
Relevant Persons.
Updates to Claims and Objections Introduction of Shell’s global system for reporting and
Process follow up on complaints. Identified Claims or Objections
will be tracked within this system. Failure to close out
complaints in the system results in escalation to senior
management and risks a breach of Shell’s social
performance standards.

Shell will continue to accept feedback from all stakeholders and work with them to
address any future concerns if they arise throughout the duration of the Prelude EP. The
process for ongoing consultation is managed in the same manner as described in
Sections 5.2.1 to 5.2.6. Shell will ensure any claims or objections, or feedback, from the
ongoing consultation are processed as per Shell’s internal claims process in a timely
manner, and any identified risks will be managed to ALARP levels as required in this EP.
In particular, Shell will continue to engage and consult with relevant stakeholders
through:
• Direct stakeholder and community engagement as part our standard business processes
• Updated factsheets and notifications prior to commencement of major activities and key
milestones
• Community Hotline number and the Prelude FLNG mailbox provided on factsheets and
our website, mechanisms through which the public (including Relevant Persons) can
share feedback or ask questions about the Prelude FLNG operations.

Consultation with relevant stakeholders also occurs via our ongoing strategic relationship
engagements (for example, with Department of Transport and Department of Agriculture,
Water and Environment) and ad hoc engagements by the External Relations and Social
Performance team at social investment events.
In addition, to ensure we receive further input from our community stakeholders, Shell
conducts an annual Prelude Pulse Survey, a community based survey that covers key
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stakeholders in Broome and Kimberley region and Darwin. The survey identifies,
assesses and measures impacts, gauges the communities’ perception of Shell and
gathers feedback.
Identified relevant Persons were emailed a Prelude EP Fact Sheet, which is also
published on Shell’s website. Where possible, Shell has tailored communication to
stakeholders. For example, marine stakeholders such as the Western Australian Fishing
Industry Council and Parks Australia were provided with maps to show the location of
Prelude in relation to fishing zones and marine parks.

6.0 Description of the Activity

6.1 Scope of the EP
This EP covers the following activities within the Operational Area (Figure 6-1) located
within permit area WA-44-L and infrastructure license WA-2-IL:
• Operations and maintenance turnarounds of the FLNG and subsea facilities
• Operation within the designated safety zone of the installation, support, supply and in-
field support vessels and helicopters required for the offshore works, commissioning &
maintenance activities and operate phase
• Product offtake tankers or bunkering vessels only when they are attached to the Prelude
FLNG (considered as petroleum activity)
• Well intervention activities using a light well intervention vessel
• Inspections, maintenance and repairs of systems and subsea infrastructure
• Emergency Response events.
Non-petroleum activities such as environmental field monitoring or metocean studies
are outside of the scope of this EP.

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Figure 6-1: Prelude EP Operational Area

This EP does not include the general transit of vessels to or from the Operational Area.
These activities will be undertaken in accordance with relevant maritime legislation,
such as the Commonwealth Navigation Act 2012, and are within the jurisdiction of

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AMSA. In addition, helicopter activities outside of a Petroleum Safety Zone (PSZ) are
not defined as petroleum activities. Therefore, activities undertaken by the vessels and
helicopters which are not carrying out petroleum activities are not considered in this
EP. Any impacts and risks outside of these activities are provided for via the HSSE and
SP Control Framework, outside of the formal EP acceptance and implementation
process, to support the transparent, whole-of-project assessment process.

6.2 Location and Timing

The Prelude FLNG Project is in WA-44-L, in Commonwealth marine waters, 200 km
offshore northwest Australia and 460 km north-north east of Broome (Figure 6-2), in
237 m from Mean Sea Level (MSL) water depth.

Figure 6-2: Location of Prelude (Permit Area WA-44-L)

The Prelude FLNG facility was towed from South Korea where it was constructed and
partially commissioned, and arrived in field in July 2017. The installation, hook-up and
commissioning occurred upon arrival of the FLNG and then the facility reached its
ready for start-up (RFSU) milestone by introducing hydrocarbons from the wells on
26 Dec 2018. Steady state operation is defined as once the facility name plate capacity
(i.e. design capacity) is reached following the completion of the well clean-up and
performance testing process. The Prelude FLNG facility is designed to stay on location
and operate for at least 25 years.
LNG, LPG and condensate will be transferred to offtake tankers with the following
estimated frequency:
• LNG – every week
• LPG – every month
• Condensate – every 2 weeks.

6.3 Prelude FLNG Facility Overview

The next few sections provide a high-level description of the layout of the Prelude
FLNG facility. There is more detailed information in Appendix A: Detailed Facility
Description.
The Prelude FLNG facility (Figure 6-3) is a turret moored offshore floating production
facility with gas processing and liquefaction units. The facility includes LNG, LPG and
condensate storage as well as facilities for exporting these products to offtake carriers.

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It is connected to the gas reservoir and wells via flexible risers routed to the turret. All
reservoir, subsea control, processing, storage and loading are controlled from the
Prelude FLNG facility. The facility will remain on station for 25 years without dry
docking and is a permanently manned facility. Periodic major maintenance or
turnarounds will be carried out in-field during operate phase. Figure 6-4 shows the
Prelude field layout.
Prelude has one drill centre with two 6-slot manifolds and seven production wells at the
drill centre DC-1P. The drill centre is located approximately 3 km south of the Prelude
FLNG facility. The Prelude FLNG facility is connected to the gas reservoir via four 12”
flowlines connecting the production manifolds to the riser base manifold.
Each flow path to the Prelude FLNG facility, consisting of flowlines and flexible risers, is
equipped with a Fail Close Riser Base Valve (FCRBV) at the Riser Base Manifold
(RBM), located at a horizontal distance of 550 m from the centre of the turret, to isolate
the Prelude FLNG facility from the flowlines inventory.
The Prelude FLNG facility is moored using 16 mooring lines connected to piles
grouped into four quadrants. A Fibre Optic (FO) cable connects the Prelude FLNG
facility to the Australian FO network onshore.
The Prelude FLNG facility itself is 488 m long, 74 m wide and has an operating draft of
19 m and is permanently moored with weathervaning capability. The main elements of
the Prelude FLNG facility are:
• An internal turret, which permanently moors the Prelude FLNG facility to the seabed via
a catenary mooring system and provides interface with subsea systems
• Topsides containing all process units & part of the utilities systems
• A substructure with all necessary marine facilities, accommodation, cargo containment
systems, and the remainder of the utilities systems:
o Storage Tanks
o Aft Machinery Space & Fwd Machinery Space
o Side by Side Mooring and LNG/LPG Offloading
o Accommodation / Living Quarters
o Tandem Mooring and Condensate offloading
o Water Intake Risers.
The substructure is separated from the Topsides by the main deck, on which piping
systems such as cooling water, steam, fuel gas, rundown and loading lines are located.
Topsides equipment is arranged in large modules over a series of process decks.

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Figure 6-3: Overview of the Prelude FLNG Facility

6.3.1 Prelude Field Safety Zones

Prelude field safety zones are published under Commonwealth of Australia Gazette
Notice: A441884 which extend around both the well infrastructure equipment and the
Prelude FLNG facility as shown in Figure 6-4.

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Figure 6-4: Prelude Field Layout and Safety Zones

6.3.2 Subsea Facilities

The subsea facilities are shown in Figure 2-1 with brief descriptions in Table 6-1.

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Table 6-1: Prelude Subsea Equipment Description

Subsea Facility Description

Wells • Drilled from a single drill centre
• 7 highly deviated/sub-horizontal wells
• Prelude’s 8th Well (P2): The well was permanently isolated from
permeable zones, fluids, and pressures using verified plugs after well
objectives were not met.
• Each well can deliver up to 250 Mmscfd (Note: Dry (water free) gas
flow rates)
• Surface Controlled Sub-Surface Safety Value (SCSSV) installed in
each well
Subsea Xmas Tree • 690bar (10,000psi) 7” Enhanced Vertical Deepwater Tree, consisting
of the following:
o Production choke valve
o Subsea venturi flowmeter
o Subsea control module (SCM)
o Pressure and temperature sensors
o Chemical injection ports (for MEG and SI/PPD)
Jumper, Flowlines & • Two 6-slot production manifolds provide tie-in for up to 12 gas
Production Manifold production wells (five spare slots)
• Manifolds have dual headers
• Flow from each well can be directed to either header
• Each manifold is connected to two flowlines (approx. 3 km in length)
and the manifolds are connected via the manifold jumpers together to
provide dual looped flow paths
• Dedicated SCM on each production manifold
Riser Base Manifold • Flowlines are connected to the four 12” flexible production risers to
(RBM) the Prelude FLNG facility via the RBM
• FCRBV installed at the RBM for each of the risers
• Dedicated SCM on the RBM
Production Risers • Prelude FLNG facility process modules are connected to the subsea
facilities via four flexible risers connected to the turret
• Design pressure of 400 bar and temperature of -20 / 128°C
• Material for the critical pressure sheath layer (i.e. PVDF) is capable of
handling Prelude fluid and design temperature
• Installed in a lazy wave configuration with allowance for excursions
around the Datum
• End connections of the risers are fitted with bend stiffener to prevent
damage to the riser’s structure from over bending
• Flexible risers are anchored at the Prelude FLNG facility using
standard hang-off devices
• A Riser Emergency Shutdown Valve is installed at the top of each
riser on board the Prelude FLNG facility
• Riser vent gas monitoring is provided to monitor diffusion of gas
through the pressure sheath into the flexible pipe annulus
Wet Parking Frame • The wet parking frame is retained at seabed as a contingency for
significant maintenance or other works. It is planned to be removed
from the seabed as with other subsea infrastructure in accordance
with the eventual plan for decommissioning.

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Umbilical and Subsea • A dynamic control umbilical links the Prelude FLNG facility to the
Distribution subsea system providing hydraulic, electrical and chemical services,
and signal and power control communications to the subsea system
• Designed to support eight production wells
• End connection is fitted with a bend stiffener to prevent damage to the
umbilical structure from over bending

Prelude subsea equipment is described in Table 6-1, with the status and location
outlined in the Table 6-2, noting the inclusion of the Prelude P2 abandoned well and
Concerto-1 exploration well. The maintenance of the subsea infrastructure is
described in the Section 6.4.3, and well integrity management in Section 6.4.4.
Table 6-2 Prelude Subsea Infrastructure Inventory

Infrastructure Status Production Location

Permit
Wells – 7 Production Active WA-44-L Prelude field safety zone (Gazette
wells Notice: A441884)
Well – P2 Plugged and WA-44-L Prelude field safety zone (Gazette
abandoned Notice: A441884)
(subsurface only 2).
Low Pressure
wellhead connector
converted to
subsea production
tree parking
mandrel
Concerto-1 Plugged and WA-44-L Latitude -13.674473
exploration well abandoned with (previously WA- Longitude 123.343885
wellhead removed 371-L)
Subsea Xmas Tree Active WA-44-L Prelude field safety zone (Gazette
Notice: A441884)
Jumper, Flowlines & Active WA-44-L Prelude field safety zone (Gazette
Production Manifold Notice: A441884)
Riser Base Manifold Active WA-44-L Prelude field safety zone (Gazette
(RBM) Notice: A441884)
Production Risers Active WA-44-L Prelude field safety zone (Gazette
Notice: A441884)

Wet parking frame Contingency WA-44-L Prelude field safety zone (Gazette
Notice: A441884)
Umbilical and Subsea Active WA-44-L Prelude field safety zone (Gazette
Distribution Notice: A441884)
FLNG Mooring Active WA-44-L Prelude field safety zone (Gazette
System WA-2-IL Notice: A441884)

2Permanently isolated from permeable zones, fluids, and pressures using verified plugs in accordance with
Well Abandonment Manual (WS 38.80.31.35-Gen.)

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6.3.3 Turret Mooring System

The Turret Mooring System (TMS) is a major element that provides the station keeping
function for the Prelude FLNG facility and connects the subsea infrastructure with the
topsides process modules. The Prelude FLNG facility rotates freely about the turret
subject to the influences of the prevailing winds, waves and currents, naturally adopting
a heading (termed weathervaning). This weathervaning requires the use of a swivel
stack to transfer the production stream, chemicals, power, and communications signals
between the Prelude FLNG facility and the subsea equipment.
The Prelude FLNG facility is permanently moored and designed for cyclonic conditions
offshore NW Australia. The mooring system is designed to withstand the design 10,000
years return period cyclone event when all lines are intact. In conditions, up to and
including the 100 years return period cyclone, the mooring system offers redundancy
following failure of any one mooring line, such that in any principal loading condition will
not lead to progressive failure of the mooring system or exceed riser design limits.

6.3.4 Turret
The turret, shown in Figure 6-5, is an internal type turret and is located completely
within the boundary of the substructure at the bow of the facility. All risers and mooring
lines pass through the centre of the turret. This design enables mooring chains and
risers to be protected from ship collision and direct wave actions.

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Figure 6-5: Turret 3D View

6.3.5 Topsides and Main Deck

The process units and other key utility units are located above the main deck in the
form of modules, collectively called the Topsides. The process and utility units on the
Topsides are split-up in 8 modules, further sub-divided into 14 sub-modules, 8 infill
areas, lay-down areas, hull pipe rack with maintenance route, and 1 flare tower
including the marine and CO2 vent. Figure 6-6 shows a plan view of Prelude FLNG
facility detailing the location of the process and utility sub-modules and the key
equipment contained per sub-module.
The process fluid from the wells passes through the Turret module to the processing
module on the Topsides. The key function and equipment per modules are described
below:
• Module 1S (1S1, 1S3) contains the inlet facilities and primarily separates the well
stream into gas and liquid flows. This unit receives and conditions the feed gas and
liquid hence located close to the turret area. Module 1S3 includes installed depletion
compressor and its auxiliaries, which shall not be operated during the early phase of the
well life.

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• Module 2S1 contains the acid gas recovery unit (AGRU) absorption column, gas
dehydration (mole sieve dryers) & mercury removal (Hg guard bed) units. The
regeneration facilities for the acid gas removal unit are located in module 3P1.
• Module 1P (1P1, 1P2) contains the NGL extraction, fractionation and booster
compression units. Because of the amount of light liquid hydrocarbons (C2, C3, C4) and
lower integration requirement with other units, the fractionation unit is located as far from
the accommodation block as possible. For the same reason, this unit is located in the
opposite side of the mooring location of the LNG/LPG carrier (when alongside). The
condensers and accumulators are located on an elevated level to provide sufficient
suction head (NPSH) for the pumps. All pumps are currently located underneath these
vessels at the lowest level in the module.
• Module 2P (2P1, 2P2, 2P3) contains the liquefaction unit. The mixed refrigerant (MR)
part in module 2P1 consists of the main cryogenic heat exchanger (MCHE) and
condensing steam turbine driven MR compressor with its coolers and knockout facilities.
The pre-cool mixed refrigerant (PMR) part in module 2P3 consists of the condensing
steam turbine driven PMR compressor with its de-superheaters and condensers and
knockout facilities. The PMR receiver and main pre-cooler (LP, MP, HP) i.e. coil wound
heat exchangers are located in module 2P2 in between the MR and PMR part.
• Module 3P (3P1, 3P2) contains the AGRU stripping section, MEG regeneration and
reclamation unit. The 3P1 module contains the solvent regeneration column, LP steam
heated re-boilers, heat exchangers, filters and pumps. The solvent drain vessel is
located on the main deck under 2S1 and solvent storage tanks are located in the hull.
Module 3P2 contains the MEG regeneration, reclamation unit and nitrogen booster
compressor and high-pressure nitrogen vessel. The nitrogen booster compressor only
operates to top-up the high-pressure nitrogen vessel.
• Module 3S1 contains the end-flash unit. This module contains the end flash vessel and
associated end flash compressor. The fuel gas system with fuel gas heaters is located
on an elevated deck. This module also contains the offloading analyser and metering
stations. The side-by-side offloading loading arms and associated manifolds are located
at main deck level. This module also contains the electrochlorination unit and CCW2
expansion vessel on the top deck.
• Module 4P (4P1, 4P2) contains seven marine steam boilers.
• Module 4S1 contains the low pressure nitrogen generation unit, de-aerators, CCW2/3
expansion vessel, air compressor. These relatively low risk units (i.e. 4P and 4S) are
located in the area between the accommodation and the process area.
The flare boom length is 155 m, inclined by 40° portside perpendicular to the hull. The
flare knock out vessels and associated equipment are located adjacent to the flare
stack structure in module FLM0.

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Figure 6-6: Main Deck and Topsides Layout Plan

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6.3.6 Water Intake Risers

The Prelude FLNG facility uses cold cooling water to increase the efficiency of the
liquefaction process efficiency and reduce plot space. Water is required to be pumped
from an average water depth of 170 m to meet the closed cooling water circuit demand.

6.3.7 Substructure
Storage Tank Layout
The following tanks are installed in the substructure:
• 6 LNG storage tanks • 1 Solvent Storage Tank
• 4 LPG storage Tanks • 1 Water Wash Storage Tank
• 6 Condensate storage tanks • 1 Chemical Spills Collection Tank
• 1 Produced water tank • Slop tanks
• 2 Off spec tanks. • 1 PMR Tank
• 2 Rich MEG tanks plus 1 Fwd Rich MEG tank • 1 Ethane Tank.
• 2 Lean MEG tanks.

The substructure is double hulled on each side extending over the full length of the
storage tanks. LNG, LPG and Condensate storage tanks are located inboard of
segregated ballast tanks covering the full length of the storage area. The tanks are fed
directly from the Topsides rundown system.
The port and starboard LNG, LPG and Condensate tanks are separated from each
other by a void space or ballast tank. The design of the hull structure is such that LNG,
LPG and condensate storage tanks are separated from the plant hazardous area by a
main deck which is designed to withstand explosion overpressure, jet fire and
cryogenic spills. The LNG, LPG tank tops are double deck type arrangement with all
piping systems above the main deck designed to survive blast overpressure load.
There are no flange connections in the piping within the double deck. Heating system is
installed to heat the transverse cofferdams and the upper portion of centreline water
ballast tanks surrounding the cargo tanks to maintain the temperature of the structure.
Aft Machinery Spaces & Fwd Machinery Spaces
The aft machinery space is enclosed within the hull with facilities arranged over 7
decks and are mechanically ventilated. The machinery space is provided with normal
access by stairways from the accommodation and the main deck. An enclosed
mechanically ventilated space is located in the forward part of the Prelude FLNG facility
to accommodate equipment associated with the turret and effluent treatment operation.
Side-by-Side Mooring and LNG/LPG Offloading/Import
LNG/LPG carriers are moored alongside the starboard side of the Prelude FLNG
facility utilising mooring lines and separated via the fenders.
Condensate Offloading via Tandem mooring
A tandem mooring and offloading system is fitted at the stern of Prelude FLNG facility
for offloading condensate cargo to a condensate tanker. The condensate tanker is
moored to the Prelude FLNG facility by a tandem mooring hawser configuration. When
not in use, the hawser is recovered.

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Accommodation / Living Quarters (LQ)

The LQ houses 170 cabins. The cabins are designed as single rooms with the option to
convert to double occupancy, therefore, a maximum of 340 POB can be
accommodated. Each cabin has a private shower/toilet facility.
Helideck(s) and Refuelling System
Two helidecks, each with a helicopter parking area are located above the
accommodation/LQ. The helideck pancake is self-draining “Safedeck” type made of
aluminium.
Helicopter refuelling package (i.e. tote tank/storage tank/recycle system/pumps) and
associated firefighting system are located on the top of the accommodation. Dispenser
cabinets comprising of the fuelling reel, filter and sampling unit are provided at each
helideck.
Provision of heli-fuel for the helicopter re-fuelling station is by way of 3 x 4000 L
portable tote tanks.

6.4 Operational Activities

The following are the activities conducted on the facility to ensure safe production of
hydrocarbon products:
• Production Operations - Activities to ensure that operations of the facility are conducted
within their defined envelopes. This includes facility hydrocarbon commissioning, start-
up and ramp-up (SURU) activities.
• Maintenance and Inspection - Activities to inspect and maintain hardware and
equipment integrity and reliability.
• Underwater Inspection, Maintenance and Repair - Activities to inspect, maintain and/or
repair the underwater/subsea facilities.
• Services - Includes the following activities:
o Maritime and Terminal Operations - activities relating to the management of access
and/or movement of marine vessels within the Safety Zone; and the management of
product offloading/import activities
o Helicopter Operations
o Management of lifting and hoisting and deck services on the facility
o Facility catering services.

6.4.1 Design Basis for Prelude FLNG and Current Status

Prelude FLNG was designed with a maximum capacity enabling up to about 12,000
tonnes per day (tpd) LNG, 2000 tpd LPG and 5000 tpd condensate production.
The key name plate capacities and technical maximums of Prelude FLNG are listed in
the Table 6-3 below.

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Table 6-3 Prelude FLNG Name Plate Capacities

Product Design Basis (MTPA)
LNG 3.6
Condensate 1.3
LPG 0.4
Total Hydrocarbon Production 5.3

Since Prelude arrived onsite in 2017, Prelude has passed many key milestones in the
journey to steady state operations. At the end of 2018, Prelude opened the wells and
commenced the start-up/ramp-up process. Due to unforeseen technical challenges,
Prelude has not yet been able to complete the start-up phase of the project which
involves the performance test runs (running the wells at the technical maximum/100%)
and getting the utilisation of Prelude up to 90%. Prelude is now expected to complete
the performance test run at the start of 2021 and reach ~90% utilisation in 2023 or
2024. As of 2020, the forecast utilisation for 2021 and 2022 is between ~50-70%.

6.4.2 Maintenance, Shutdowns and/or Turnarounds

Regular maintenance activities are carried out on a daily basis on the Facility. Facility
maintenance shutdowns and/or turnarounds are planned at regular frequencies to
conduct inspection, maintenance and/or repair works that could not be completed
during production operations. During a facility shutdown and/or turnaround, the
topsides facility is predominantly shutdown and depressurised.
Further, maintenance shutdowns/turnarounds are supported by services activities such
as helicopter operations and maritime activities including supply boat activities and
bunkering.
Temporary facilities for accommodating additional personnel, wastes accumulated and
materials may be likely required during major turnarounds, however, no other
significantly different environmental risks from those described in Section 9 are
expected. Details of the key air emissions, liquid discharges and waste generated by
these activities are outlined in the respective areas of Section 9.0. A risk assessment
and supporting demonstration that impacts and risks are managed to ALARP and
Acceptable levels will be conducted for any temporary liquid discharges or air
emissions generated by maintenance, shutdown or turnaround activities.

6.4.3 Preservation and Maintenance of Subsea Equipment

Prelude’s IMR philosophy is to inspect and maintain the installed portfolio of subsea
equipment such that its mechanical condition remains fit for the purposes specified in
its original design requirements. These include, but are not limited to, mechanical
integrity, availability, service life, and retrievability. Typical IMR activities consist of:
• regular visual inspection of equipment condition,
• inspection and, as appropriate, refurbishment of cathodic protection equipment
• ongoing management of a detailed integrity database which includes details of the
location and condition of all subsea equipment
• repair/replacement and reinstatement of failed equipment items to support continued
field operation (typically chokes, control modules, flying leads)

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• provision of contracts, tooling and spares to support an effective IMR response over life-
of-field

The Prelude Preservation and Storage strategy (2000-005-S001-SS01-G00000-UA-

5980-00004) gives an overview of the approach that is used to ensure that project
equipment is managed appropriately, including both dry and wet storage, prior to
commencing operations.
The requirement for maintenance activities on the subsea equipment are expected to
be limited because of the material selected for the equipment. However, as a result of
the high pressures and naturally occurring metocean conditions in which subsea
infrastructure operates, inspection and maintenance are required to ensure the integrity
of the infrastructure and identify any problems before they present a risk of loss of
containment or asset damage.
Through these activities Shell will meet the obligations under the OPGGS Act
(s.572(2)) to ‘maintain in good condition and repair all structures that are, and all
equipment and other property that is: (a) in the title area; and (b) used in connection
with the operations authorised by the permit, lease, licence or authority’.
In particular for Prelude P2 well, after it was permanently isolated from permeable
zones, fluids, and pressures using verified plugs in accordance with the Shell Well
Abandonment Manual, the low pressure wellhead connector was converted to a
subsea production tree parking mandrel. The design of the mandrel coupled with the
final cement abandonment plug rendered the P2 wellbore and associated low pressure
wellhead unusable for future well activity (i.e. well production). In its current
configuration, the P2 well parking mandrel provides subsea flexibility during XT
changeouts within the DC-1P well centre and the intent is to retain the tree parking
mandrel in its current status to allow use should there be requirement over the course
of the field life.
In addition, through the implementation of the Prelude Preservation and Storage
Strategy, information will be gathered over the life of the facility that ensures an
appropriate level of planning for the eventual decommissioning. In doing so, this
ensures Shell has plans in place to meet its regulatory obligation to remove property in
accordance with the requirements of s.572 of the OPGGS Act.
The P2 subsea parking mandrel, complete with remaining low pressure wellhead
system, will be rendered into final abandoned condition via severance and recovery of
the conductor at the end of field life or when equipment field activities end if this occurs
sooner. The majority of maintenance activities comprise non-intrusive inspections using
ROVs such as general visual inspection, cathodic protection probe inspection and
checks, marine growth checks, seabed and free span checking and measurements,
azimuth and mooring surveys. Typical maintenance activities for P2 well comprise
general visual inspection and cathodic protection survey. These surveys determine the
physical condition of the subsea assets.
The wet parking frame will be left in situ for potential future use for subsea campaigns
which require its use throughout the Prelude FLNG facility asset life. It will be
appropriately monitored and maintained to ensure its purpose of intended use is
maintained and also enabling future retrieval when it is no longer intended to be used.
Surveillance via installed monitoring equipment includes continuous monitoring of
pressures, temperatures, flow rates and sand production rates at various locations in
the subsea system, supported by lab testing of produced fluids and the chemicals

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injected to maintain the production system. This ensures that the status of the system
is continually known, and that any early indications of potential degradation/failure are
acted upon promptly to maintain the condition of equipment/ hardware and structures in
an appropriate state until cessation of production.

Frequency of inspection is generally selected based on Risk Based Inspection (RBI)

principles; this approach is integral to Prelude’s subsea inspection philosophy. Based
on RBI, risk analysis is performed which considers the consequences of failure of each
equipment item in terms of impact to people (safety), environment, production and
costs of repair. From this assessment, a risk level and corresponding inspection effort
are determined and assigned to each equipment type. An overall inspection plan and
frequency of inspection is then provided for all structural components of the subsea
system.
Subsurface Integrity Testing (SIT) inspection and maintenance activity on well systems
is performed as per the current frequency specified within the Well Failure Model
(WFM) and monitored / tracked within the eWIMS. Inspection and maintenance
activities on subsea equipment is performed as per the current frequency specified,
monitored and tracked within the Integrity Management System Application (IMSA).
Typically, subsea systems are designed so that design life exceeds operating life, with
the intent that proactive, planned repair activities are not necessary. However,
unplanned intervention to address breakdown maintenance of certain equipment items
is an inevitable part of the operation of any subsea field – most commonly, subsea
chokes, control modules and flying leads may require replacement during the life of
field; less commonly, well and flowline jumpers may require intervention if damaged.
Should repair and/or replacement of subsea infrastructure be required, a detailed risk
assessment will be done prior to the repair activity. Repair activities are those required
when a subsea system or component is degraded, damaged or has deteriorated to a
level outside of acceptance limits as defined by design codes.
During these maintenance activities, minimal fluids are released as lines are
depressurised and flushed prior to any intervention activities. Where equipment has
failed, it is retrieved for replacement, the failed items are either refurbished and stored
onshore for future use, or disposed/scrapped in an approved safe location onshore.
Marine Growth Covers (MGC) are provided for all critical Subsea hardware assets with
ROV Interfaces. To maintain the infrastructure, a long term corrosion cap (LTCC) was
manufactured and installed on the P2 well subsea parking mandrel. The objectives of
the MGCs and LTCC are to reduce the amount of soft growth and thus reduce the time
required for the ROV to clean the interfaces required during the commissioning phase
and during an intervention in the operating life of the asset. Excess marine growth
removal maybe undertaken on Prelude subsea facilities with an ROV. Various
techniques for marine growth removal include:
• Water jetting – use of high pressure water
• Brush systems – use brushes attached to an ROV
• Use of chemicals
• Sand/abrasive blasting.

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The long term corrosion cap was designed such that it has the capability of allowing
injection of a corrosion inhibitor into the wellhead system, as such preserving all
sealing bores and profiles across the wellhead internal housing.
Corrosion inhibitor injected into the P2 well parking mandrel via ROV, provides a
cushion of inhibitor across all critical sealing profiles of the well head housing. The
inhibitor is selected in accordance with the Prelude Chemical Selection Process.
Minor chemical discharge may be associated with marine growth removal, although
non-chemical method is preferred.
An Underwater Services Contract is in place to execute all subsea/underwater
inspections and maintenance activities. Subsea activities are typically performed from a
support installation vessel via one or more ROVs. Typical support vessels use a DP
system to avoid anchoring. The Underwater Services Contract manages the scope for
planning, preparing and executing routine and ad-hoc underwater intervention and
inspection for Prelude FLNG Moorings and Subsea Hardware. The contractor is
responsible for the following:
• Perform engineering and develop procedures associated with the intervention and
inspection activities
• Supply appropriate vessel(s) and associated support personnel
• Provision of all materials and equipment
• Undertake the intervention and inspection activities in accordance with approved
procedures
• Provision of all reporting and documentation.

6.4.4 Well Intervention and Workover

There are no planned well intervention or well workover activities during the life of this
EP. However, well intervention activities through the subsea tree system may be
required due to a number of unforeseen circumstances that may occur during the
operations phase of a wells lifecycle.
Interventions may be undertaken for reservoir surveillance, enhancing productivity,
assessing wellbore condition and restoring well integrity. Well interventions may also
include tree/wellhead maintenance, logging or surveys, mitigating safety critical failures
(e.g. failed safety valve), and production logging improvement activities.
When top-up of the well annulus with MEG is required, up to 15 bbl of MEG will be
injected into the annulus in 5 – 10 bbl increments (pressure dependent). After allowing
the MEG to “flip” with the base oil in the annulus, annulus pressure will be bled off with
returned base oil being flushed to the surface via the flow/return umbilical. Injection of
MEG and return of base oil will be repeated until the required volume of MEG has been
pumped into the annulus. Returned liquids will be stored onboard the Light Well
Intervention Vessel in the waste liquid tank. As this is a closed loop system, there are
no planned discharges to sea.
If required during the life of this EP, well operations would be executed and managed
by the Wells Delivery team, interfacing and concurring with asset groups as
appropriate. The work would be conducted in accordance with Prelude FLNG Permit to
Work controls. Management of these activities are detailed in the Prelude WOMP.

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ROV(s) are used from the vessel in support of the well intervention activities. The
ROV(s) are a standard work class ROV, with any specialist equipment or tooling
required mounted on the ROV. An observation class ROV may also be employed to
assist the work class ROV where appropriate.
With respect to well integrity, management of the wells will be in accordance with the
NOPSEMA accepted Prelude WOMP, which sets out requirements for ongoing
wellhead monitoring and leak detection. Through implementation of the WOMP, Shell
is meeting its regulatory obligation under the OPGGS Act (s.572(2)) to ‘maintain in
good condition and repair all structures that are, and all equipment and other property
that is, in the title area and used in connection with the operations’.
For wells and seabed infrastructure, through the development and eventual
implementation of the decommissioning plan, Shell will meet its obligations under s.
572 (3) of the OPGGS Act ‘to remove from the title area all structures that are, and all
equipment and other property that is, neither used nor to be used in connection with
the operations’.

6.4.5 Light Well Intervention

6.4.5.1 Light Well Intervention (LWI) Vessel Description

The following describes a typical vessel to be used for offshore well intervention
activities.
Planned well intervention activities are executed by LWI vessels with an accepted
vessel Safety Case for those activities consistent with the OPGGS(S) Regs 2009.
Should the vessel scope demonstrate functionality or significant hazards that are not
captured within the accepted vessel Safety Case scope, then a re-assessment shall be
undertaken accordingly. This shall be followed by a consultation and revision to the
existing vessel safety case, as required by the OPGGS(S) Regulations 2009.
Shell has framework agreements in place with a number of providers. The scope
under these agreements is provision of a fully integrated LWI service including vessel,
subsea intervention device (SID), ROVs, slickline/wireline services, bleed-off package
services and project management under Shell’s Well Engineering oversight. Having
agreements in place with a number of providers improves response time to a potential
well integrity issue requiring an intervention in the event the primary LWI service
provider is unable to supply the requested service.
The selected LWI vessel contractor shall ensure that such a LWI vessel has the
required vessel documentation accepted by the various legislative bodies for use
offshore in Australian waters. More details on the specific LWI vessel used on Prelude
can be found within the datasheet included in the vessel Safety Case.
Light Well Intervention Vessel Safety Critical Equipment

Safety critical equipment will be detailed in the LWI vessel safety case. Where
applicable each LWI vessel safety case is reviewed by Shell in conjunction with the
Prelude FLNG Safety Case (in force) to ensure that there are no omissions with
regards to safety critical equipment. There are a number of key controls with interfaces
to the Prelude FLNG Safety Case (in force) and this EP, which shall be scrutinised at
this review of the vessel safety case, and thereafter at the maritime vessel assurance
reviews. Examples of physical controls that relate to environmental protection and this
EP include:
• Navigation equipment and aids (including audible and visible warnings)

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• Communication equipment
• Dynamic positioning system
• Lifting equipment
• Back-up power supply
• Emergency shut-down, alarm and lighting systems.

Remotely Operated Vehicle(s) (ROVs)

ROVs are used from the LWI vessel in support of the LWI activities. The ROVs are
standard work class ROVs, with any specialist equipment or tooling required mounted
on the ROVs. Observation ROVs may also be employed to assist the work class ROVs
where appropriate.
Subsea Intervention Device (SID)

Well interventions require well bore access into ‘live’ wells. A SID is deployed and
utilised to allow wellbore access while maintaining well control. Basic particulars of a
SID are listed below. Any selected vessel contractor shall ensure that such a SID shall
meet the functionality and operability as per the approved WOMP as required by the
OPGGS (Resource Management and Administration) Regulations 2011. SID typical
details are as follows:
• System Working Pressure: 10,000 psi
• Umbilical pressure rating: 7,500 psi (4x ¾” (19mm) lines)
• Min Bores Size: 7-3/8” (187mm)
• SID Ram/Valve configuration: Capacity for two (2) sealing barriers in place for all well
interventions
• Subsea Connector Type: 18-3/4” (476mm) H4 10,000 psi
• Subsea Intervention Lubricator Length: 60ft.

6.4.5.2 Light Well Intervention (LWI) Operational Considerations

With two well barriers in place the tree cap can be recovered. After tree cap recovery
the SID will be deployed onto the subsea production tree using a heave compensated
crane on the LWI vessel. After deployment of the SID onto the subsea production tree
the SID will be pressure tested to Closed-In Tubing Head Pressure (CITHP) plus a
margin. SID umbilicals and slickline/wireline will be compensated.
Control of the production tree valves during well entry will be via the SID umbilical
system or managed through a lock out interface with FLNG. The LWIV has the
necessary tooling for ROV intervention also.
If required, subsea production tree valve cavities and the A-annulus may be flushed/
topped with inhibited MEG from the LWI vessel. This will most likely be completed
using a down line from the LWI vessel or via ROV as an alternative.
With sufficient well barriers in place the SID will be placed on the next well or recovered
to the LWI vessel. A tree cap will be installed and pressure tested with an ROV.

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6.4.6 Potential Light Well Intervention Requirements

Light well interventions required on the Prelude wells, post suspension plug recovery,
will in principle be the result of a well integrity issue needing an investigation or repair.
These activities may need to be carried out at any point during the life of this EP.
Potential well intervention triggers may include:
• Completion tubing leak
• Production packer leak
• Loss of A-annulus integrity
• Subsurface safety valve functionality issues
• Subsea production tree valve leak.

Well interventions most likely require a well entry using slickline/wireline. This can be
executed by a vessel with Light Well Intervention capability similar to the LWI vessel
used for the planned suspension plug recovery operation. As a result, Section 6.4.5.1
Light Well Intervention (LWI) Vessel Description and all requirements and associated
references are also applicable to contingency LWI activities.
Although the in-well activities and objectives are different, the risks and hazards are
effectively identical to suspension plug recovery. Hence the Commissioning & LWI Well
Integrity Risk Register will apply for these operations.
Below are some of the contingency LWI activities listed which may be applicable from
suspension plug recovery through to the commissioning and production (including
start-up) activities.
6.4.5.1 Slickline/Wireline interventions
The likely types of slickline/wireline intervention that may be required during the
Prelude well life cycle are detailed further in this section.
6.4.6.2 Deep Set Plugs
Setting a deep-set plug would most likely be triggered by a well integrity concern,
coming from a tubing or production packer leak into the A-annulus.
If the leak is in the tubing, then the most likely plug will be a slickline conveyed plug set
in the nipple profile located in the completion tail pipe.
A leak of the production packer itself will require a high expansion plug set in the 7”
(178 mm) liner. This plug will be run on e-line and potentially requires the use of a
tractor and setting tool.
6.4.6.3 Sub-Surface Safety Valve Repairs
Sub-surface safety valve functionality issues may also lead to an intervention. The
most involved operation that would be attempted would be to run an insert valve. This
operation involves four main slick line runs (with possible drift and check runs in
between). The operational steps are:
• Run in Hole (RIH) and exercise the sub surface safety valve. This involves shifting the
sleeve up and down using a dedicated wireline tool.
• RIH with a lock open tool. This trip involves stroking the sleeve of the sub surface safety
valve down and locking it in this position using a dedicated wireline tool.

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• RIH with a punch/ communication tool. This dedicated wireline tool will create hydraulic
communication with the sub surface safety valve control line.
• RIH with the insert safety valve. The valve is deployed on a lock that sets in the nipple
profile above the subsurface safety valve. With the lock set in the profile the valve
straddles the punched port allowing the control fluid to reach and function the insert
safety valve.

6.4.6.4 Investigation Run

Prior to, for example, rectifying a leak and/or subsurface safety valve issue, it is likely
that an investigation tool will be deployed on slickline/wireline to better understand the
issue. Typical examples would be:
• RIH and run an acoustic tool to detect the location of a potential tubing leak.
• RIH and run a downhole camera to obtain an imagine of the sub-surface safety valve
internal condition.
• RIH and run a calliper or drift run to investigate any changes in well bore internal
geometry.

6.4.6.5 Well Surveillance Well Entry

Although not envisaged it is possible that a slickline/wireline run is required for well
surveillance purposes e.g.:
• RIH with an expandable gauge carrier to obtain downhole pressure and temperature in
case the permanent downhole gauge is not functioning.
• RIH with a drift run to investigate a potential blockage below the completion tail pipe.

6.4.6.6 Well Production Reinstatement

In the unlikely event that sand production becomes an issue, there is the opportunity to
run a slickline/wireline deployed sand screen hung off in the nipple profile located in the
completion tail pipe.

6.4.7 Isolations from FLNG

With FLNG on location it is imperative that isolations are put in place during a LWI to
isolate the wells and the well intervention activities from the production facility and
other wells. A number of FLNG Operating Procedures are in place to ensure adequate
and tested isolations are in place. These isolations are critical in preparation for
handover of the well from the asset to the wells team and vice versa at the start and
end of the intervention activities. The specific procedures deal with:
• Prelude Subsea Isolation Strategy
• Lock-Out Tag-Out (LOTO) Manual
• Well Handover Procedure.

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6.5 Logistic Support Arrangement

6.5.1 Aviation Support Location

Prelude requires logistics support from the mainland of Australia. The primary means of
mobilising personnel to the facility is by helicopter via Broome as the primary helicopter
base. Djaradjin (also known as Lombadina) is used as a refuelling point to optimise
operational efficiency dependant on environmental conditions. These helicopter bases
may change in the future as company requirements may change. However, as the
onshore bases are excluded from the scope of this EP, any change to the location of
the base does not change the environmental risks from helicopter operations within
WA-44-L.

6.5.2 Infield Support Vessel

The Infield Support Vessels (ISVs) support the operations of the Prelude FLNG facility,
primarily fulfilling the role of Standby Vessels. Typically, two ISVs are present in the
Prelude field area based on a rotation basis.
The ISVs perform the following roles and functions:
• Each ISV is provided with a Fast Rescue Craft (FRC) to facilitate rescue of persons from
sea and where necessary the guiding of free floating life rafts.
• In a major emergency, the ISV acts as an emergency evacuation vessel.
• Acting as a place of safety or having the ability to transfer to an alternative vessel
offshore or helicopter.
• Firefighting with capability commensurate with notation Fi-Fi 1, with remote operated
main water monitors and foam drenching system.
• Ability to provide Tier 1 oil spill response.
• 24/7 security surveillance for other vessels that might pose a threat to Prelude using
existing systems (e.g. radar, floodlighting and other means of surveillance).
• Monitoring and maintaining traffic activities in the safety zone.
• Perform side by side berthing and unberthing operations for LNG and LPG Tankers.
• Perform tandem berthing and unberthing, hawser and hose handling operations of
offtake Condensate tankers.
• Provide support during offloading of tankers.
• Enable transfer of FLNG TTLS (Pilots) and Service Technicians, Surveyors to the
carriers and tankers upon arrival and return to FLNG on departure.
• Pilot transfer from the FLNG is primarily from the Preludes bow catcher located on
Preludes Stern with secondary access being at the Port and Starboard doors.
• Perform environmental monitoring (or another similar vessel) if possible.

6.5.3 Supply Vessels

The Shell Marine Logistics Group supports the Prelude FLNG activities through the
provision of the following contracted vessels including but not limited to:
• Platform Supply Vessel (PSV) (Figure 11) or Multi-purpose Platform Supply Vessel
(MPSV)

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• Anchor Handling Tug / Supply (AHTS)

• The scope of work for these dedicated vessels comprises of the following:
o Port operations (Loading / discharging of cargo and specialist equipment)
o The safe transportation of cargo / equipment to and from FLNG facility
o Offshore Installation operations (Discharging / back-loading of cargoes and
specialist equipment)
o Anchor handling / towing operations (AHTS vessels only)
o Infield emergency response support e.g. oil spill response, helicopter operations
standby support.
Shell has contracted supply vessels that will support the Prelude activities. Up to four
supply vessels are planned to be utilised during the installation and hook-up activities,
and one supply vessel during normal operations. The MPSV can also be called to
respond to subsea inspection and intervention requirements. The following is an
example to contextualise/visualise.

6.5.4 Accommodation Support Vessels

Potentially during major maintenance activities or shutdowns, an accommodation
support vessel (ASV) may be necessary to provide accommodations for additional
personnel in excess of the FLNG’s capacity.

7.0 Description of the Receiving Environment

As required by regulations 13(2) and 13(3) of the OPGGS(E) Regulations, a description
of the receiving environment that may be affected by the activities (both planned and
unplanned) covered by this EP is provided in this section. The information contained in
this section has been used to inform the assessment of environmental impacts and
risks presented in Section 9.3 to Section 9.14.
The spatial extent of the receiving environment encompasses the physical, biological
and socio-economic receptors that may be affected by planned and unplanned
activities. The majority of the impacts and risks from the activities covered by this EP
occur in close proximity to the Prelude FLNG facility (i.e. within the Operational Area
around the facility and associated infrastructure), however some impacts and risks may
extend further. The credible worst-case hydrocarbon release scenarios determined by
modelling studies are predicted to present the greatest spatial extent of all the impacts
and risks identified. The outer boundary of the area that may be influenced by the
petroleum activities, identified by the modelling and referred to as the Zone of Potential
Influence (ZPI), has been used as the outer boundary for the description of the
receiving environment. The worst-case hydrocarbon releases during operations have a
remote to extremely remote likelihood of occurring, and Shell implements a range of
controls to ensure such incidents are prevented, and mitigated to ALARP and
Acceptable Levels. The ZPI for the combined worst-case credible hydrocarbon spills
from the Prelude FLNG facility and associated petroleum activities is shown in Figure
7-1 and this represents the low exposure thresholds described further in Table 9-78.
Refer to Section 9.13 for additional information on hydrocarbon spill modelling and risk
management and associated impact thresholds applied for the assessment.

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The description of the receiving environment considers environmental receptors that

are protected under the EPBC Act, including:
• World heritage and national heritage values
• Ramsar wetlands
• listed threatened species, migratory species and threatened ecological communities
• values and sensitivities within the Commonwealth marine environment.

The EPBC Act Protected Matters Search Tool (PMST) was used to identify
environmental receptors protected under the Act. Two EPBC Act PMST reports were
generated; one based on the Operational Area and one based on the combined
entrained, dissolved and surface ZPI. PMST Reports for both the Operational Area and
ZPI are provided in Appendix 14.0.

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Figure 7-1: ZPI for the Prelude FLNG facility and associated Petroleum Activities

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7.1 Physical Environment

7.1.1 Seabed
The Operational Area is located in the Timor Sea on the outer continental slope
between 200 and 300 m depth. The seabed within the Operational Area, and within the
WA-44-L permit more broadly, is relatively flat and featureless. Baseline environmental
study results for the Prelude development show the seabed is characterised by
unconsolidated sand, silt and mud (Shell 2009). No reefs or extensive areas of rocky
substrate have been observed.
Notable seabed features in the ZPI beyond the Operational Area include the coral reefs
and islands that occur throughout the region. The closest of these features, Browse
Island, is located some 39 km southeast of Prelude. There are also numerous reefs,
banks and shoals throughout the Timor Sea, which host diverse biological
communities. Other notable seabed features in the ZPI include Ashore Reef, Cartier
Island, Scott Reef, the Rowley Shoals, and numerous reefs, banks and islands off the
Kimberley and Pilbara coasts. Refer to Section 7.2 for further discussion of the
biological communities associated with these seabed features.

7.1.2 Climate
Prelude is situated in the tropics and experiences a monsoonal climate with two
seasons. The Australian northern monsoon generally occurs between December and
March (Figure 7-2). It is associated with the inflow of moist west to north-westerly winds
into the monsoon trough, producing convective cloud and heavy rainfall over northern
Australia. During the cooler months (June - September), the sub-tropical ridge that lies
over continental Australia drives stable and persistent easterly winds over the region.
The Australian cyclone season officially runs from November to April, although very few
storms have occurred in November. The chance of experiencing an intense category 4
or 5 cyclone is highest in March and April. At the start of the cyclone season, the most
likely area to be affected is the Kimberley and Pilbara coastline and offshore areas
including the Operational Area, with the area threatened later in the season extending
further south.

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300 40

35
250
30

Temperature (°C)
200
25
Rainfall (mm)

150 20

15
100
10
50
5

0 0
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Rainfall (mm) Max. temperature Min. temperature

Figure 7-2: Long-term maximum and minimum temperatures and mean rainfall from
Cygnet Bay (closest Bureau of Meteorology climate station to Prelude FLNG). Data
sourced from Bureau of Meteorology (n.d.)

7.1.3 Oceanography
The regional currents influencing the offshore waters off northern and western Australia
are shown in Figure 7-3. The majority of water movement off northern Western
Australia is poleward, with the water being relatively warm and low in nutrients
(DEWHA 2008). A strong seasonal wind regime is closely associated with seasonality
in surface currents in the region, including the seasonal strength of trade winds in the
equatorial Pacific Ocean which drive the Indonesian Throughflow (ITF).
The project is located within the North West Marine Region (NWMR) 3 which
experiences semi-diurnal tides. Tidal ranges are large - 0.8 m neaps and 5 m springs
(RPS 2018) - and strongly influence currents in the region. Notably, tidal amplitudes
seem to be retained at large distances offshore and travel initially in a north-east
direction in the deeper waters of the region (RPS 2018). The tidal current component is
imposed over the synoptic-scale flow.
In addition to synoptic-scale and tidal currents, locally generated wind-driven currents
also influence water movement within the Operational Area and ZPI. These are more
variable and are superimposed over large-scale flows.

3 A series of bioregional plans have been developed by the Commonwealth government. These plans are
intended to help improve the way decisions are made under the EPBC Act. The Operational Area (and much
of the ZPI) overlaps the area covered in the Marine bioregional plan for the North-west Marine Region:
prepared under the Environment Protection and Biodiversity Conservation Act 1999 (Department of
Sustainability, Environment, Water, Population and Communities (DSEWPaC) 2012a); hence the
Operational Area is within the NWMR.

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Figure 7-3: Regional synoptic-scale currents off north-western Australia (from DEWHA
2008)

7.1.4 Water Quality

Water quality in the vicinity of Prelude is generally high. A field survey in 2018 was
carried out in WA-371-P (including the now WA-44-L) title area, which consisted 40
sampling stations within four identified ‘impact’ zones (A-D) and an outlying ‘reference’
zone (R). The positioning and extent of impact zones A-C was determined on the basis
of the location of the following main operational areas within the proposed facilities
layout:
• The sites for the FLNG facility (Zone B);
• The subsea well structures (Zone C); and
• Proposed site of subsea infrastructure (Zone A).

The fourth impact zone (Zone D) comprised an area encompassing the above three
areas, while the reference sites were located outside the external boundaries of Zone
D.
Water samples were collected using Niskin water samples at depths of 5 m (surface),
150 m (mid-depth) and 5 m above the seabed (bottom) for in-situ and lab analyses.
Additional in-situ samples were taken at each site at depths ranging from 1 m-200 m.
Upon surfacing, in-situ measurements were immediately collected using a Hydrolab
minisonde 5 probe.

Results from this 2018 baseline water quality survey, in conjunction with the Prelude
EIS indicated potential contaminants, such as metals and hydrocarbons, were low and
often below the laboratory detection limits (Shell 2009), refer Table 7-1: Water quality
for survey results. These results are consistent with other survey results in the Timor

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Sea (Ross et al. 2017). Nutrient and turbidity levels in the water column were also low
compared to nearshore waters, which is typical for offshore waters and is consistent
with other surveys in the region (Ross et al. 2017). The average salinity for the
receiving water is approximately 34.5ppt (ERM 2008).
Table 7-1: Water quality
Parameter Range value (min – max) Sample location/ condition
pH Range (min-max) 7.15 – 8.21 In-situ measurement collected in and
around the development area
Dissolved Oxygen (mg/L) 7.27 - 4.19 DO was found to be same along the
sampling point but varied by depth
TSS (mg/l) Near surface: 3.7 Data obtained from a study conducted
Mid depth: 5.0 for INPEX in Exploration Permit WA-
285-P (RPS, 2007b) located
Near seabed: 3.8 immediately adjacent to WA-371-P
Heavy Metals Observed little spatial or Mean concentration of metals in all
vertical variation in seawater sampling zones were below trigger
barium, nickel, iron, zinc and values identified in ANZECC
cadmium concentrations guidelines

Water quality in the immediate vicinity of the Prelude FLNG facility is slightly lower due
to routine discharges from the facility (e.g. grey water, sewage, PFW etc.). The area
impacted by these discharge streams is localised; refer to Section 9.9 for further
information.

7.1.5 Sediment Quality

Sediments at Prelude are described as very soft carbonate silts to a depth of about 10
m below the seabed. A field survey was undertaken within the same spatial extent as
described above in Section 7.1.4 for sediment quality testing. Sediment samples were
collected using a Van Veen benthic grab sampler with 0.1 m2 sample capacity. The
average water depth at each sampling station was approximately 240 m. Baseline
studies showed concentrations of potential contaminants, such as hydrocarbons and
metals, were typically low and similar to other studies in the region (Ross et al. 2017,
Shell 2009), survey results are listed in Table 7-2 and survey locations in relation to the
Prelude FLNG are in Figure 7-4.
Table 7-2: Prelude Baseline Sediment quality results
Parameter Range value (min – max) Sample location/ condition
Particle size distribution Samples from Zones A-D In-situ measurement collected in
were primarily of silt (56.75% and around the development
± 9.06) and clay area
(29.89% ± 4.22)
Total Organic Carbon (% wt) 0.06 – 2.9 This concentration is considered
as a low percentage range of
organic material. Also, there was
no clear spatial pattern in mean
total organic carbon
concentrations between
sampling zones
Oil & Grease (mg/kg) * C6 – C9: 5 Levels of oil and grease above
the limits of reporting (200

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C10 – C14: 114 mg/kg) were found only in one

C15 – C28: 203 sample from the site of the
FLNG facility (Zone A: 3400
C29 – C36: 50
mg/kg) and two samples from
the reference zone (Zone R: 530
and 1660 mg/kg). The Prelude
turret location is located at the
sediment sampling point D5.
Heavy Metals Barium: 14.2 – 204 Concentrations of cadmium
Chromium: 11- 16.5 (Cd), lead (Pb) and mercury
(Hg) were below the laboratory
Iron: 3,205 – 5,830
detectible level
Nickle: 8.9 -11.2
* mean concentration of all sample points

Figure 7-4: Prelude FLNG Baseline Sediment Sampling Locations from 2008.
Installation of subsea facilities (e.g. wells, xmas trees, flowlines and umbilicals) resulted
in isolated areas of sediment disturbance. Higher concentrations of potential
contaminants from drill cuttings and fluids, such as barite, may occur in the cuttings
piles from historical drilling activities. These areas are expected to be highly localised
(i.e. within 100’s of metres from wellheads).

7.1.6 Air Quality

No specific information concerning air quality in the local airshed area is available.
However, the Operational Area is approximately 200 km from the Kimberley coastline,
which itself is a remote and unindustrialised area. Therefore, the air quality is unlikely

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to be subject to considerable anthropogenic effects with the exception of the Prelude

FLNG facility. Emissions from commercial shipping are likely to represent the main
source of localised and temporary impacts on air quality. Production facilities in the
broader region, such as the Montara FPSO facility (approximately 188 km from the
Operational Area), the Ichthys FPSO (approximately 17 km from the Operational Area)
and the future Shell Crux normally not manned platform (165 km from the Operational
Area), are also expected to incrementally influence local and regional air quality.
In a regional context, the main contributors to particulate levels are ambient wind-borne
dust and smoke from seasonal bush fires that are characteristic across the Kimberley
regions. International contributors to reduced air quality in the project area may also
include the likes of ‘slash-and-burn’ agricultural methods and other large forest fires in
South-East Asian countries (Vadrevu et al. 2014; Kim Oanh et al. 2018).

7.1.7 Underwater Noise

The baseline underwater noise monitoring program in support of the Prelude EIS
recorded the following natural and anthropogenic features of:
• several regular fish choruses (i.e. schooling fish calling en masse)
• several great whale calls including humpback whales, pygmy blue whales in late
October 2006 and possible minke whale calls
• persistent vessel noise
• seismic survey noise associated with marine seismic survey signals.

The biological noise sources recorded in the nearby Ichthys field were similar and
included regular fish choruses, infrequent calls from nearby fish and several whale calls
from humpback whales, pygmy blue whales, minke whales and other unidentifiable
species (INPEX Browse 2010). Anthropogenic noise sources recorded included low
frequency noise from vessels and that generated from seismic surveys being
conducted in the region (INPEX Browse 2010).

7.2 Biological Environment

7.2.1 Benthic Communities

7.2.1.1 Bare Sediment

Surveys of benthic habitats within the Operational Area showed low density epibenthic
communities of deposit and filter feeders on bare sediments, which is typical of this
habitat in the region (Baker et al. 2008). Infauna were dominated by polychaete worms,
which accounted for approximately 80% of individual infauna sampled (Shell 2009).
This finding is consistent with other studies across the region, which showed infauna
communities in similar water depths are dominated by polychaetes and crustaceans
(Heyward et al. 1997). Given the water depth within the Operational Area, no benthic
primary producers will occur due to the lack of photosynthetically active radiation
reaching the seabed.
Bare sediment habitats are also the most common habitat type within the ZPI, although
there are discrete areas of other benthic habitat types associated with features such as
islands and shoals, such as corals, macroalgae, seagrasses and mangroves
(discussed below).

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7.2.1.2 Corals
While hard (zooxanthellate) corals are not present within the Operational Area, they are
widespread throughout the ZPI in relatively shallow (< 50 m) waters. Much of the open
water environment in the ZPI is too deep for growth of hard corals, and coral
communities are typically associated with the named islands, shoals, reefs and banks
throughout the ZPI, including:
• Browse Island (approximately 39 km from the Operational Area)
• Echuca Shoal (approximately 61 km from the Operational Area)
• Heywood Shoal (approximately 81 km from the Operational Area)
• Cartier Islet (approximately 136 km from the Operational Area)
• Seringapatam Reef (approximately 136 km from the Operational Area)
• Goeree Shoal (approximately 144 km from the Operational Area)
• Vulcan Shoal (approximately 146 km from the Operational Area)
• Scott Reef (approximately 159 km from the Operational Area)
• Ashmore Reef (approximately 169 km from the Operational Area)
• Hibernia Reef (approximately 194 km from the Operational Area).

Coals reef communities are also widespread along the coastlines of Indonesia and
Timor-Leste, including:
• Rote Island (approximately 322 km from the Operational Area)
• Timor (approximately 381 km from the Operational Area)
• Sawu Island (approximately 388km from the Operational Area
• Sumba (approximately 494 km from the Operational Area).
Corals, particularly reef-forming corals, form an important component of benthic
communities by providing habitat. In turn, this habitat supports relatively diverse
associated communities, such as fish assemblages and macroalgal communities. Coral
rubble from dead hard coral colonies also results in in-situ sediment production, which
may be an important source of biogenic sediments at banks and shoals in the Timor
Sea (Heyward et al. 2012).
Corals in the region are thought to spawn seasonally, with two distinct mass spawning
events in autumn and spring observed (Gilmour et al. 2009, Rosser and Gilmour 2008).
This contrasts with other coral reef communities in the Indo-Pacific, such as the Great
Barrier Reef and Ningaloo Reef, which typically exhibit a single annual mass spawning
event. Coral reefs in the Timor Sea exhibit recruitment from both local (i.e. self-
seeding) and distant (e.g. reefs located 10’s to 100’s of kilometres away) propagules
(Gilmour et al. 2013). This has implications for the recovery of coral reefs following
disturbance, such as bleaching events or cyclones.
7.2.1.3 Macroalgae & Seagrasses
Like corals, much of the ZPI does not receive sufficient photosynthetically active
radiation at the seabed to support macroalgae and seagrass communities. The areas
that do are typically associated with physical features such as reefs, banks, shoals,
islands and the mainland coasts of Australia, Indonesia and Timor-Leste. Macroalgae

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and seagrass communities in these areas provide relatively complex habitat structure
that supports greater species richness and diversity. Primary productivity from these
communities also supports food webs through direct grazing and consumption of
detritus.
Macroalgae are an important feature in the seabed communities at several offshore
banks and shoals in the ZPI, particularly calcareous green algae in the genus
Halimeda. Geological coring studies of several Timor Sea banks and shoals indicates
extensive deposition of carbonate sediments from Halimeda spp. (Heyward et al.
1997), which may account for the creation and maintenance of these geological
structures near the sea surface. Seagrasses at banks and shoals tends to be less
common and more ephemeral than macroalgae, with surveys showing considerable
temporal variability at the scale of years (Heyward et al. 2012).
7.2.1.4 Mangroves
Mangroves are widely distributed along the coastlines within the ZPI, including
Indonesia (Timor and Sumba), the Pilbara and the Kimberley coastline. Mangroves
habitats are of environmental value due to the shoreline stabilisation and habitat they
provide. Many fauna species either complete their life cycles within mangrove habitats,
or utilise mangroves during particular life history stages (e.g. nursery habitat for
juveniles (Robertson and Duke 1987). The nearest potential mangrove habitat to the
Operational Area are the islands and mainland coast of the Kimberley region, over 200
km from the Prelude LNG facility.

7.2.2 Pelagic Communities

7.2.2.1 Plankton
Plankton are organisms, typically small in size, whose movements are determined
largely by currents rather than active movement (e.g. swimming). Plankton
communities are often categorised into two groups: phytoplankton (drifting plants) and
zooplankton (drifting animals).
Surveys in the Operational Area found phytoplankton communities to be highly diverse
but low in abundance. Key groups identified include dinoflagellates (Dinophyceae),
diatoms (Bacillariophyceae) and Prasinophyceae. The most abundant species included
Prasinophyte sp. (Prasinophyceae); Gyrodinium sp. and Heterocapsa sp.
(Dinophyceae); Pseudonitzschia sp., Cylindrotheca closterium, Chaetoceros sp.,
Thalassionemafrauenfeldii and Nitzschia longissima (Bacillariophyceae) (Shell 2009).
Phytoplankton in the wider region is similar to that observed in the project area with
relatively high diversity in certain groups recorded such as diatoms, dinoflagellates and
coccolithophorids (Hallegraeff and Jeffrey 1984).
Zooplankton samples collected in July 2008 found crustacean assemblages to be
primarily dominated by copepod species (Shell 2009). Overall densities of zooplankton
assemblages were relatively low and typical of low nutrient open ocean environments
in the region. A few samples were dominated by euphausiids or chaetognaths (Shell
2009).
Some fauna groups, such as fish and crustacean species, often have a planktonic
larval stage following which they assume a free-swimming or benthic existence. The
larval fish community within the Operational Area was relatively diverse and abundant;
however, species composition was primarily dominated by neritic species, which have
little or no commercial value (Shell 2009). Commercial species identified came from
groups typical of a range of marine habitats including pelagic shelf systems and both

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coastal and deep sea demersal habitats. Larvae were identified from the following
groups which have commercially targeted species: Berycidae, Carangidae (trevally and
jacks), Lutjanidae (tropical snappers), Serranidae (cods), and Scombridae (mackerels
and tunas).
7.2.2.2 Pelagic Fish & Invertebrates
Free swimming pelagic fauna within the Operational Area and ZPI are expected to
include pelagic fishes, marine turtles, seasnakes, squid, and cetaceans. Several of
these fauna groups (e.g. whale sharks, several cetacean species, marine turtles) are
listed threatened and / or migratory under the EPBC Act; these species are considered
in Section 7.2.4 Threatened Ecological Communities.
Small pelagic fishes, such as sardines and anchovies, form an important trophic link
between microscopic planktonic communities (e.g. zooplankton feeding on
phytoplankton) and larger consumers (e.g. tunas). Small pelagic fishes are expected to
be broadly distributed throughout the tropical pelagic environment given the relatively
homogeneous nature of the open sea, with food availability and predation also
influencing the distribution and abundance of these species.
The distribution of larger pelagic fishes (e.g. tunas, bonito, blue sharks etc.) are
expected to mirror the distribution of small pelagic fishes, as small pelagic fishes are
the primary prey of these larger species. Several pelagic fish species, such as marlin,
swordfish and mackerel, are important for commercial and recreational fisheries,
although fishing effort in the Operational Area and much of the ZPI is very low. The
commercially important southern bluefin tuna is thought to spawn in the north-eastern
Indian Ocean, although this species is not fished within the Operational Area or ZPI.

7.2.3 Key Ecological Features

Key Ecological Features (KEFs) are elements of the Commonwealth marine
environment that are considered to be of regional importance for either a region’s
biodiversity or its ecosystem function and integrity. There are no KEFs present within
the Operational Area; several KEFs have been identified within the ZPI. A summary of
the KEFs overlapped by the ZPI are shown in Figure 7-5 and listed in Table 7-3.

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Figure 7-5: Locations of KEFs within the ZPI

Table 7-3: Descriptions of KEFs within the ZPI, including distance from Prelude FLNG

KEF Distance Description

from
Prelude
(km)
Continental 14 Communities with high species biodiversity and endemism
Slope Demersal There is a high diversity of demersal fish assemblages on the
Fish Australian continental slope from the North West Cape to the edge of
Communities the NMR. The continental slope between North West Cape and the
Montebello Trough has more than 500 fish species, 76 of which are
endemic, which makes it the most diverse slope bioregion in the
whole of Australia.
The KEF covers a vast area of approximately 33,182 km2.
Ancient 41 Unique seafloor feature with ecological properties of regional
coastline at significance
125 m depth The areas of hard substrate along this ancient coastline, which
contour follows the 125 m depth contour, are thought to provide biologically
important habitats in areas otherwise dominated by soft sediments;
thereby providing for higher species diversity and richness relative to
the wider region. The topographic complexity of these escarpments
may also facilitate vertical mixing of the water column providing a
relatively nutrient-rich environment for species present on the

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KEF Distance Description

from
Prelude
(km)
escarpment. The KEF encompasses an area of approximately
16,190 km2.
Seringapatam 131 High productivity and aggregations of marine life
Reef and The coral communities at Seringapatam and Scott Reefs play a key
Commonwealth role in maintaining species richness and aggregations of marine life.
waters in the The reefs and the waters surrounding them attract aggregations of
Scott Reef marine life including migratory cetaceans. Green and hawksbill
Complex turtles nest during the summer months on Sandy Islet on South Scott
Reef. These species also inter-nest and forage in the surrounding
waters.
Scott Reef is a particularly biologically diverse system and includes
more than 300 species of reef-building corals, approximately 400
mollusc species, 118 crustacean species, 117 echinoderm species,
around 720 fish species and several species of sea snakes.
Ashmore Reef 134 High productivity and aggregations of marine life
and Cartier Ashmore Reef is the largest of only three emergent oceanic reefs
Island and present within the north-eastern Indian Ocean and is the only
surrounding oceanic reef in the region with vegetated islands. The emergent reefs
Commonwealth are known to provide areas of enhanced primary productivity in
waters otherwise oligotrophic environments.
Ashmore Reef and Cartier Islands and the surrounding
Commonwealth waters are regionally important for feeding and
breeding aggregations of seabirds and shorebirds, and other marine
life. Ashmore Reef regularly supports more than 40,000 waterbirds
(those ecologically dependent on wetlands) and is estimated to
support as many as 100,000 seabirds in a twelve month period (Hale
and Butcher 2013).
The marine habitats supported by the reefs are nationally and
internationally significant, providing habitat for diverse and abundant
marine reptile (including feeding, nesting and inter-nesting areas for
green, hawksbill and loggerhead turtles) and marine mammal
populations, including dugongs.
Species at Ashmore and Cartier include more than 225 reef-building
corals, 433 molluscs, 286 crustaceans, 192 echinoderms, and 709
species of fish. Thirteen species of sea snakes occur in high
numbers at Ashmore and Cartier reefs but are thought to be in
decline (Threatened Species Scientific Committee 2010a).
Carbonate bank 206 Unique seafloor feature with ecological properties of regional
and terrace significance
system of the While little is known about this KEF, the carbonate banks and terrace
Sahul Shelf system of the Sahul Shelf is considered regionally important because
of their role in enhancing biodiversity and local productivity relative to
their surrounds, largely due to the presence of elevated hard
substrates. The seabed features are thought to create enhanced
productivity and biodiversity as a result of upwellings of cold nutrient-
rich water at the heads of the channels.
The KEF covers an area of approximately 41,158 km2. The banks
rise to depths of 150 m – 300 m and are separated from each other
by narrow meandering channels which are up to 150 m deep. The
hard substrates of the banks are thought to support a high diversity
of benthic organisms.

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KEF Distance Description

from
Prelude
(km)
Canyons linking 384 High productivity and aggregations of marine life
the Argo Canyons linking the Argo Abyssal Plain with Scott Plateau covers an
Abyssal Plain area of approximately 836 km2. The Bowers and Oats canyons are
with the Scott major canyons on the slope between the Argo Abyssal Plain and
Plateau Scott Plateau and deeply cut into the Scott Plateau at depths of
approximately 2,000 m – 3,000 m. The ocean area above the
canyons is thought to be an area of moderately enhanced
productivity, attracting aggregations of fish, sharks, toothed whales
and dolphins.
Pinnacles of the 457 Unique seafloor feature with ecological properties of regional
Bonaparte Basin significance
The limestone pinnacles in the western Bonaparte Depression are
expected to support a diverse community in an otherwise oligotrophic
system. More than 110 pinnacles occur in the Bonaparte Depression,
covering a total area of more than 520 km2. The pinnacles are
thought to be the eroded remnants of underlying strata and can be
up to 50 m high and 50 km–100 km long.
Mermaid Reef 523 High productivity and aggregations of marine life
and The Rowley Shoals consist of three atoll reefs, Clerke, Imperieuse
Commonwealth and Mermaid Reef, which support 214 coral species and around 530
waters species of fish. The steep changes in slope around the reef also
surrounding attract a range of migratory pelagic species such as dolphins, tuna,
Rowley Shoals billfish and sharks. The coral communities of Mermaid Reef are also
an important feature.
The enhanced productivity at the shoals is thought to be facilitated by
the breaking of internal waves in the waters surrounding the reefs,
causing mixing and re-suspension of nutrients from water depths of
500 – 700 m into the photic zone.
Glomar Shoals 941 High productivity and aggregations of marine life
The Glomar Shoals (approximately 786 km2) are a submerged littoral
feature located approximately 150 km north of Dampier on the
Rowley shelf at depths of 33 m – 77 m. While biological data is
limited, the fish of Glomar Shoals are believed to be a subset of reef-
dependent species. The shoals are known to be an important area
for a number of commercial and recreational fish species such as
Rankin cod, brown-striped snapper, red emperor, crimson snapper,
bream and yellow-spotted triggerfish.
Exmouth 1,127 Unique seafloor feature with ecological properties of regional
Plateau significance
The Exmouth Plateau is a large, mid-slope, continental margin
plateau that ranges in depth from approximately 800 to 3,500 m.
The Exmouth Plateau is overlaid by an interface between the ITF and
the Indian Ocean Central Water. This interface constitutes a potential
shear zone (with associated mixing). The seascape of the Exmouth
Plateau is not considered to be unique by Falkner et al. (2009) in
their review of KEFs in the northwest marine region, however the
geological origin and potential enhanced upwelling due to the
Exmouth Plateau may constitute unique environmental values
(DSEWPaC 2012a).
Canyons linking 1,256 Unique seafloor feature with ecological properties of regional
the Cuvier significance
Abyssal Plain The Canyons linking the Cuvier Abyssal Plain and the Cape Range
and the Cape Peninsula KEF lies off the north-west coast of Australia. Interactions

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KEF Distance Description

from
Prelude
(km)
Range with the Leeuwin current and strong internal tides are thought to
Peninsula result in upwelling at the canyon heads, thus creating conditions for
enhanced productivity in the region (Brewer et al. 2007). Note that
such upwelling may not result from the presence of the canyons, but
from other factors such as local wind stress (e.g. upwelling off the
Capes region in south-western Australia) and internal waves (Taylor
and Pearce 1999, Woo et al. 2006).
Commonwealth 1,304 High productivity and aggregations of marine life
waters adjacent Ningaloo reef is globally significant as the only extensive coral reef in
to Ningaloo Reef the world that fringes the west coast of a continent. It is also globally
significant as a seasonal aggregation site for whale sharks. The
Commonwealth waters adjacent to Ningaloo Reef and associated
canyons and plateau are interconnected and support the high
productivity and species richness of Ningaloo Reef. The Leeuwin and
Ningaloo currents interact on the seaward side of the reef, leading to
areas of enhanced productivity (DoEE n.d.).
Demersal slope 1,747 High levels of biodiversity and endemism
and associated The Demersal slope and associated fish communities of the Central
fish communities Western Province provides important habitat for demersal fish
of the Central communities. In particular, the continental slope of the Central
Western Western provincial bioregion supports demersal fish communities
Province characterised by high diversity compared with other, more intensively
sampled, oceanic regions of the world. Its diversity is attributed to the
overlap of ancient and extensive Indo-west Pacific and temperate
Australasian fauna (Williams et al. 2001).
Western rock 1,862 Ecological role on the west coast continental shelf
lobster The Western rock lobster KEF covers a considerable portion
(~40,000 km2) of continental shelf waters on the lower west coast of
Western Australia and was established in recognition of the
presumed ecological role played by the western rock lobster
(Panulirus cygnus) in shelf waters (DSEWPaC 2012b).
Wallaby Saddle 1,898 High productivity and aggregations of marine life
The Wallaby Saddle is located in water depths ranging from 4,000 to
4,700 m. The Wallaby Saddle is an abyssal geomorphic feature
linking the north-west margin of the Wallaby Plateau with the upper
continental slope margin of the Carnarvon Basin.
Perth Canyon 1,934 Higher productivity that attracts feeding aggregations of deep-
and adjacent diving mammals and large predatory fish
shelf break, and The Perth Canyon is the largest canyon on the Australian margin
other west coast and, together with numerous smaller submarine canyons that incise
canyons the continental slope of southern Western Australia, is expected to
have high biodiversity values.
The west-coast canyons are believed to be associated with small
periodic upwellings that locally increase productivity and attract
aggregations of marine life. In the Perth Canyon, interactions
between the canyon topography and the Leeuwin Current induce
clockwise-rotating eddies that transport nutrients upwards in the
water column from greater depths. Due to the canyon’s depth and
the Leeuwin Current’s barrier effect, this remains a subsurface
upwelling (depths greater than 400 m), which confers ecological
complexity that is typically absent from canyon systems in other
areas (Pattiaratchi 2007).

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7.2.4 Threatened Ecological Communities

Threatened Ecological Communities (TECs) are protected under Part 3 of the EPBC
Act and are MNES. The PMST report for the ZPI indicated that the monsoon vine
thickets on the coastal sand dunes of the Dampier Peninsula TEC lies within the ZPI,
approximately 285 km from the Operational Area at the closest point.
The identification of this TEC by the PMST report is an artefact of the method used to
derive the search area for the PMST. This TEC lies entirely above the high water mark
and will not credibly be impacted by a worst-case hydrocarbon spill. Hence, this TEC is
not considered further in this EP.
No other TECs were identified that may credibly be affected by the petroleum activities
considered in this EP.

7.2.5 Ramsar Wetlands

Sites recognised under the Convention on Wetlands of International Importance (the
Ramsar Convention), referred to as Ramsar wetlands, are protected under Part 3 of
the EPBC Act and are MNES. Several Ramsar wetlands were identified within the ZPI;
the environmental values for these Ramsar wetlands are shown in Figure 7-6 and
summarised in Table 7-4.

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Figure 7-6: Ramsar Wetlands within the ZPI

Table 7-4: Descriptions of Ramsar Wetlands within the ZPI, including distance from
Prelude FLNG

Ramsar Distance Description

Wetland from
Prelude
(km)
Ashmore reef 162 Ashmore Reef supports an abundance and diversity of birds; 72
national nature species have been recorded at this Ramsar site, with 12 recorded
reserve breeding (Hale and Butcher 2013). Ashmore Reef was designated as
a Ramsar wetland based on the following characteristics:
• Ashmore is the largest of the atolls in the region and has been
managed for the purposes of conservation for three decades.
• Each of the wetland types is in near natural condition, with low
densities of coral predators and disease.
• The three islands represent the only vegetated island within the
Timor Province bioregion.
• It supports 64 threatened species.
• It is considered a true ‘hotspot’ of biological diversity within the
Timor Province bioregion and within the broader north-west
marine region.
• It supports 47 species of waterbird listed as migratory under
international treaties and three species of migratory turtle (green,
hawksbill and loggerhead). It also supports breeding of green
and hawksbill turtles, dugongs and 20 species of waterbird.
• It regularly supports over 40,000 waterbirds including large
numbers of migratory shorebirds and breeding seabirds (Hale
and Butcher 2013).
Ashmore Reef is also recognised as a KEF and is within the
Ashmore Reef Australian Marine Park (AMP) (refer to 7.2.3).
Roebuck bay 474 The Roebuck Bay Ramsar site is located at Roebuck Bay near
Broome in north Western Australia. Roebuck Bay has a very large
tidal range which exposes around 160 square kilometres of mudflat,
covering most of the Ramsar site. The eastern edge of the site is
made up of microscale linear tidal creeks.
The intertidal mud and sand flats support a high abundance of
bottom dwelling invertebrates, which are a key food source for
waterbirds. The site is one of the most important migration stopover
areas for shorebirds in Australia and globally. For many shorebirds,
Roebuck Bay is the first Australian landfall they reach on the East
Asian Australasian Flyway. The total numbers of waders using the
site each year is estimated at over 300 000. The northern beaches
and Bush Point provide important high tide roost sites.
Eighty-mile 610 Eighty-mile Beach Ramsar site, located between Port Hedland and
beach Broome in north Western Australia, is made up of Eighty-mile Beach
and, 40 km to the east, Mandora Salt Marsh. Eighty-mile Beach is a
220 km section of coastline and adjacent intertidal mudflats.
Eighty-mile Beach is characterised by extensive mudflats supporting
an abundance of macroinvertebrates which provide food for large
numbers of shorebirds. More than 472,000 migratory waders have
been counted on the mudflats during the September to November
period.

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Ramsar Distance Description

Wetland from
Prelude
(km)
The site is considered to be one of the major arrival and departure
areas for migratory shorebirds visiting Australia, particularly on
southward migration. It is one of the most important sites in the world
for the migration of the Great Knot.
The dales 1,994 The Ramsar site has a near-pristine system of seven watercourses
collectively known as The Dales. The Dales includes permanent and
perennial streams, permanent springs, and include the majority of
surface water on the Island. Most rainfall on Christmas Island filters
down through the soil and limestone, and surface runoff only occurs
after heavy rain. The Dales contain numerous wetland types
including surface and karst features, and inland and coastal
wetlands.
The Dales support a number of unique ecological and geomorphic
features including anchialine cave communities, surface karst
including the unique stepped tufa deposits at Hugh's waterfall, a
stand of Tahitian chestnuts, a large number of endemic terrestrial
species and a significant number of seabirds including Abbott's
booby, red-footed booby and the brown booby, all of which breed at
the site.

7.2.6 Commonwealth Marine Area

The Operational Area is located within the Commonwealth marine area, which includes
any part of the sea, including the waters, seabed and airspace, within Australia’s
exclusive economic zone and/or over the continental shelf of Australia, that is not state
or NT waters. The Commonwealth marine area stretches from three to 200 nm from
the coast.

7.2.7 WA Mainland Coastline

The WA mainland coastline lies over 200 km from the Prelude FLNG at the closest
point, with several parts of the Kimberley and Pilbara coastlines within the outer edge
of the ZPI. These coastlines support a diverse array of coastal and nearshore marine
habitats including coral reefs, sandy beaches, rocky shores, seagrass meadows,
mangroves, wetlands, estuaries, creeks and rivers. These environments in turn support
a number of fauna, including EPBC listed seabirds and migratory shorebirds, turtles,
sea snakes, dugongs, cetaceans, fish, sharks and rays (refer to Section 7.2.8).
The WA nearshore and coastal areas provide Indigenous and European heritage
value, as well as cultural, social and economic values such as local tourism and
recreation (refer to Section 7.3). The nearshore and coastal habitats also support a
number of culturally and commercially significant marine fauna species such as marine
turtles, dugongs, fish and prawns.

7.2.8 Threatened and Migratory Species

A total of 102 EPBC Act listed species considered to be MNES (46 and 91 listed as
threatened or migratory respectively) were identified as potentially occurring within the
ZPI, of which a subset of 34 were identified as potentially occurring within the
Operational Area (Table 7-5). The full list of marine species identified from the

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protected matters search is provided in Appendix B: EPBC Act Protected Matters

Reports.
Note that a number of MNES that will not credibly be impacted by the petroleum
activities considered were identified by the PMST Report for the ZPI (e.g. terrestrial
species within the wider ZPI). These PMST report results are an artefact of the method
used to generate the area upon which the report is based; this method occasionally
overlaps small areas of the terrestrial environment that will not credibly be impacted by
the petroleum activity. These have been excluded from further consideration and are
not listed in Table 7 3; justifications for these exclusions are provided in Appendix B:
EPBC Act Protected Matters Reports.
Table 7-5: EPBC Act listed threatened and migratory fauna potentially occurring within
the Operational Area and ZPI identified by the PMST reports that may credibly be
impacted by the petroleum activities considered in this EP

Species Name Common Name Threatened Migratory Operational

Status Status Area / ZPI
Mammals
Balaenoptera borealis Sei whale Vulnerable Migratory Operational
Area
Balaenoptera edeni Bryde's whale N/A Migratory
Balaenoptera Blue whale Endangered Migratory
musculus
Balaenoptera Fin whale Vulnerable Migratory
physalus
Megaptera Humpback whale Vulnerable Migratory
novaeangliae
Orcinus orca Killer whale, orca N/A Migratory
Physeter Sperm whale N/A Migratory
macrocephalus
Tursiops aduncus Spotted bottlenose N/A Migratory
(Arafura/Timor Sea dolphin
populations) (Arafura/Timor Sea
populations)
Balaenoptera Antarctic Minke N/A Migratory ZPI
bonaerensis Whale, Dark-
shoulder Minke
Whale
Dugong dugong Dugong N/A Migratory
Eubalaena australis Southern Right Endangered Migratory
Whale
Orcaella heinsohni Australian snubfin N/A Migratory
dolphin
Sousa chinensis Indo-Pacific N/A Migratory
(sahulensis) (Australian)
humpback dolphin
Reptiles
Caretta Loggerhead turtle Endangered Migratory Operational
Area
Chelonia mydas Green turtle Vulnerable Migratory

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Species Name Common Name Threatened Migratory Operational

Status Status Area / ZPI
Dermochelys Leatherback turtle, Endangered Migratory
coriacea leathery turtle, luth
turtle
Eretmochelys Hawksbill turtle Vulnerable Migratory
imbricata
Lepidochelys olivacea Olive ridley turtle, Endangered Migratory
pacific ridley turtle
Natator depressus Flatback turtle Vulnerable Migratory
Aipysurus Short-nosed Critically N/A ZPI
apraefrontalis seasnake endangered
Aipysurus Leaf-scaled Critically N/A
foliosquama seasnake endangered
Crocodylus porosus Salt-water N/A Migratory
crocodile, estuarine
crocodile
Sharks and Rays
Anoxypristis Narrow sawfish, N/A Migratory Operational
cuspidata knifetooth sawfish Area
Carcharodon White shark, great Vulnerable Migratory
carcharias white shark
Glyphis garricki Northern river Endangered N/A
shark, New Guinea
river shark
Isurus oxyrinchus Shortfin mako, N/A Migratory
mako shark
Isurus paucus Longfin mako N/A Migratory
Manta birostris Giant manta ray, N/A Migratory
chevron manta ray,
Pacific manta ray,
pelagic manta ray,
oceanic manta ray
Pristis zijsron Green sawfish, Vulnerable Migratory
dindagubba,
narrowsnout
sawfish
Rhincodon typus Whale shark Vulnerable Migratory
Carcharias taurus Grey nurse shark Vulnerable N/A ZPI
(west coast (west coast
population) population)
Lamna nasus Porbeagle, N/A Migratory
Mackerel Shark
Manta alfredi Reef manta ray, N/A Migratory
coastal manta ray,
inshore manta ray,
Prince Alfred's ray,
resident manta ray
Pristis clavata Dwarf sawfish, Vulnerable Migratory
Queensland sawfish

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Species Name Common Name Threatened Migratory Operational

Status Status Area / ZPI
Pristis pristis Freshwater sawfish, Vulnerable Migratory
largetooth sawfish,
river sawfish,
Leichhardt's
sawfish, northern
sawfish
Birds
Actitis hypoleucos Common sandpiper N/A Migratory Operational
Area
Anous stolidus Common noddy N/A Migratory
Anous tenuirostris Australian lesser Vulnerable N/A
melanops noddy
Calidris acuminata Sharp-tailed N/A Migratory
sandpiper
Calidris canutus Red knot, knot Endangered Migratory
Calidris ferruginea Curlew sandpiper Critically Migratory
endangered
Calidris melanotos Pectoral sandpiper N/A Migratory
Calonectris Streaked N/A Migratory
leucomelas shearwater
Fregata ariel Lesser frigatebird, N/A Migratory
least frigatebird
Fregata minor Great frigatebird, N/A Migratory
greater frigatebird
Numenius Eastern curlew, far Critically Migratory
madagascariensis eastern curlew endangered
Papasula abbotti Abbott's booby Endangered N/A
Ardenna carneipes Flesh-footed N/A Migratory ZPI
shearwater, Fleshy-
footed shearwater
Ardenna pacifica Wedge-tailed N/A Migratory
shearwater
Arenaria interpres Ruddy turnstone N/A Migratory
Calidris alba sanderling N/A Migratory
Calidris ruficollis Red-necked stint N/A Migratory
Calidris tenuirostris Great knot Critically Migratory
endangered
Charadrius bicinctus Double-banded N/A Migratory
plover
Charadrius Greater sand plover, Vulnerable Migratory
leschenaultii large sand plover
Charadrius mongolus Lesser sand plover, Endangered Migratory
Mongolian plover
Charadrius veredus Oriental plover, N/A Migratory
oriental dotterel

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Diomedea Amsterdam Endangered Migratory

amsterdamensis albatross
Diomedea Southern royal Vulnerable Migratory
epomophora albatross
Diomedea exulans Wandering albatross Vulnerable Migratory
Fregata andrewsi Christmas Island Endangered Migratory
frigatebird, Andrew's
frigatebird
Glareola maldivarum Oriental pratincole N/A Migratory
Hydroprogne caspia Caspian tern N/A Migratory
Limicola falcinellus Broad-billed N/A Migratory
sandpiper
Limnodromus Asian dowitcher N/A Migratory
semipalmatus
Limosa lapponica Bar-tailed godwit N/A Migratory
Limosa lapponica Bar-tailed godwit Vulnerable N/A
baueri (baueri), Western
Alaskan bar-tailed
godwit
Limosa lapponica Northern Siberian Critically N/A
menzbieri bar-tailed godwit, endangered
bar-tailed godwit
(menzbieri)
Limosa limosa Black-tailed godwit N/A Migratory
Macronectes Southern giant- Endangered Migratory
giganteus petrel, southern
giant petrel
Macronectes halli Northern giant petrel Vulnerable Migratory
Numenius phaeopus Whimbrel N/A Migratory
Onychoprion Bridled tern N/A Migratory
anaethetus
Pandion haliaetus Osprey N/A Migratory
Phaethon lepturus White-tailed N/A Migratory
tropicbird
Phaethon lepturus Christmas Island Endangered N/A
fulvus white-tailed
tropicbird, golden
bosunbird
Phaethon rubricauda Red-tailed tropicbird N/A Migratory
Philomachus pugnax Ruff (reeve) N/A Migratory
Pluvialis fulva Pacific golden plover N/A Migratory
Pluvialis squatarola Grey plover N/A Migratory
Pterodroma mollis Soft-plumaged Vulnerable N/A
petrel
Rostratula australis Australian painted- Endangered Migratory
snipe, Australian
painted snipe

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Sterna dougallii Roseate tern N/A Migratory

Sternula albifrons Little tern N/A Migratory
Sternula nereis nereis Australian fairy tern Vulnerable N/A
Sula dactylatra Masked booby N/A Migratory
Sula leucogaster Brown booby N/A Migratory
Sula sula Red-footed booby N/A Migratory
Thalassarche carteri Indian yellow-nosed Vulnerable Migratory
albatross
Thalassarche cauta Tasmanian shy Vulnerable Migratory
albatross
Thalassarche cauta White-capped Vulnerable Migratory
steadi albatross
Thalassarche Campbell albatross, Vulnerable Migratory
impavida Campbell black-
browed albatross
Thalassarche Black-browed Vulnerable Migratory
melanophris albatross
Thalassarche steadi White-capped Vulnerable Migratory
albatross
Thalasseus bergii Crested tern N/A Migratory
Tringa brevipes Grey-tailed tattler N/A Migratory
Tringa glareola Wood sandpiper N/A Migratory
Tringa nebularia Common N/A Migratory
greenshank,
greenshank
Tringa stagnatilis Marsh sandpiper, N/A Migratory
little greenshank
Tringa totanus Common redshank, N/A Migratory
redshank
Xenus cinereus Terek sandpiper N/A Migratory

7.2.8.1. Listed Threatened Species Conservation Advice & Species Recovery

Plans
The Commonwealth publishes recovery plans and conservation advice for a number of
species listed as threatened under the EPBC Act. These documents are intended to
assist in preventing the decline, and enhance the recovery, of threatened species. The
requirements of the species recovery plans and conservation advice (Table 7-6) for
threatened species identified within the ZPI were considered to identify any aspects
that may be applicable to the impact and risk assessment (Section 9.3 to Section 9.14).

Table 7-6: Conservation advice for EPBC Act listed threatened species identified within
the ZPI considered during environmental risk assessment

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Species / Recovery plan / Key threats Relevant Conservation Actions

Sensitivity conservation advice (date identified in the
issued) recovery
plan/conservation
advice
All Vertebrate Fauna
All vertebrate Threat abatement plan for the Marine debris No explicit management actions for non-
fauna impacts of marine debris on fisheries related industries (note that
the vertebrate wildlife of management actions in the plan relate
Australia's coasts and oceans largely to management of fishing waste
(Commonwealth of Australia (e.g. “ghost” gear), and state and
2018) Commonwealth management through
regulation.
Mammals
Sei whale Approved conservation advice Noise interference Assess and manage acoustic disturbance
Balaenoptera borealis (sei
whale) (Threatened Species Vessel disturbance Assess and manage physical disturbance
Scientific Committee 2015a) and development activities

Blue whale Conservation management Noise interference Assessing and addressing anthropogenic
plan for the blue whale: A noise
recovery plan under the
Environment Protection and Vessel disturbance Minimising vessel collisions
Biodiversity Conservation Act
1999 2015-2025
(Commonwealth of Australia
2015a)
Fin whale Approved conservation advice Noise interference Assessing and addressing anthropogenic
for Balaenoptera physalus (fin noise
whale) (Threatened Species
Scientific Committee 2015b) Vessel disturbance Minimising vessel collisions

Humpback Approved conservation advice Noise interference For actions involving acoustic impacts
whale for Megaptera novaeangliae (example pile driving, explosives) on
(humpback whale) (Threatened humpback whale calving, resting, feeding
Species Scientific Committee areas, or confined migratory pathways
2015c) site specific acoustic modelling should be
undertaken (including cumulative noise
impacts)
Vessel disturbance Ensure the risk of vessel strike on
humpback whales is considered when
assessing actions that increase vessel
traffic in areas where humpback whales
occur and, if required appropriate
mitigation measures are implemented to
reduce the risk of vessel strike
Southern right Conservation management Vessel disturbance Addressing vessel collisions
whale plan for the southern right
whale: a recovery plan under Noise interference Assessing and addressing anthropogenic
the Environment Protection noise
and Biodiversity Conservation
Act 1999 2011-2021
(DSEWPaC 2012c)
Reptiles
Light pollution Minimise light pollution

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Species / Recovery plan / Key threats Relevant Conservation Actions

Sensitivity conservation advice (date identified in the
issued) recovery
plan/conservation
advice
Loggerhead Recovery plan for marine Chemical and Ensure that spill risk strategies and
turtle, green turtles in Australia terrestrial discharge response programs include management
turtle, (Commonwealth of Australia (oil pollution) for turtles and their habitats
leatherback 2017)
turtle, Vessel disturbance Vessel interactions identified as a threat;
hawksbill no specific management actions in
turtle, flatback relation to vessels prescribed in the plan
turtle, olive Noise interference No explicit relevant management actions;
ridley turtle noise interference identified as a threat
Leatherback Approved conservation advice Vessel disturbance No explicit relevant management actions;
turtle for Dermochelys coriacea vessel strikes identified as a threat
(Leatherback Turtle)
(Threatened Species Scientific
Committee 2008a)
Short-nosed Approved conservation advice No additional threats None applicable
seasnake for Aipysurus apraefrontalis identified (ex. marine
(short-nosed sea snake) debris)
(Threatened Species Scientific
Committee 2010a)
Leaf-scaled Approved conservation advice No additional threats None applicable
seasnake for Aipysurus foliosquama identified (ex. marine
(leaf-scaled sea snake) debris)
(Threatened Species Scientific
Committee 2010b)
Sharks and Rays
White shark Recovery plan for the white No additional threats None applicable
shark (Carcharodon identified (ex. marine
carcharias) (DSEWPaC 2013) debris)
Northern river Approved conservation advice Habitat degradation / Implement measures to reduce adverse
shark for Glyphis garricki (northern modification impacts of habitat degradation and/or
river shark) (Threatened modification
Species Scientific Committee
2014a)
Sawfish and river shark Identify risks to important sawfish and
multispecies recovery plan river shark habitat and measures need to
(Commonwealth of Australia reduce those risks
2015b)
Green sawfish Approved conservation advice Habitat degradation / No explicit relevant management actions;
for green sawfish (Threatened modification habitat loss, disturbance and modification
Species Scientific Committee identified as a threat
2008b)
Sawfish and river shark Identify risks to important sawfish and
multispecies recovery plan river shark habitat and measures need to
(Commonwealth of Australia reduce those risks
2015b)
Whale shark Approved conservation advice Vessel disturbance Minimise offshore developments and
Rhincodon typus whale shark transit time of large vessels in areas close
(Threatened Species Scientific to marine features likely to correlate with
Committee 2015d) whale shark aggregations and along the
northward migration route that follows the

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Species / Recovery plan / Key threats Relevant Conservation Actions

Sensitivity conservation advice (date identified in the
issued) recovery
plan/conservation
advice
northern Western Australian coastline
along the 200 m isobath
Grey nurse Recovery plan for the grey No additional threats None applicable
shark (west nurse shark (Carcharias identified (ex. marine
coast taurus) (Department of the debris)
population) Environment 2014)
Dwarf sawfish Approved conservation advice Habitat degradation / No explicit relevant management actions;
for Pristis clavata (dwarf modification habitat loss, disturbance and modification
sawfish) (Threatened Species identified as a threat
Scientific Committee 2009)
Sawfish and river shark Identify risks to important sawfish and
multispecies recovery plan river shark habitat and measures need to
(Commonwealth of Australia reduce those risks
2015b)
Freshwater Approved conservation advice Habitat degradation / No explicit relevant management actions;
sawfish for Pristis pristis (largetooth modification habitat loss, disturbance and modification
sawfish) (Threatened Species identified as a threat
Scientific Committee 2014b)
Sawfish and river shark Identify risks to important sawfish and
multispecies recovery plan river shark habitat and measures need to
(Commonwealth of Australia reduce those risks
2015b)
Birds
Migratory Wildlife conservation plan for Habitat degradation / Ensure all areas important to migratory
shorebird migratory shorebirds modification shorebirds in Australia continue to be
species 4 (Commonwealth of Australia considered in development assessment
2015c) processes
Albatrosses National recovery plan for Marine pollution No explicit relevant management actions;
and giant threatened albatrosses and pollution identified as a threat
petrels 5 giant petrels (DSEWPaC 2011)
Australian Approved Conservation Advice Habitat degradation / No explicit relevant management actions;
lesser noddy for Anous tenuirostris modification habitat degradation/ modification
melanops (Australian lesser identified as a threat
noddy) (Threatened Species
Scientific Committee 2015e)
Red knot, knot Approved Conservation Advice Pollution / No explicit relevant management actions;
for Calidris canutus (Red knot) contamination pollution identified as a threat
(Threatened Species Scientific
Committee 2016a)

4 Red knot, great knot, greater sand plover, lesser sand plover and bar-tailed godwit.

5 Several albatrosses and giant petrels were identified as potentially occurring: Amsterdam albatross,
southern royal albatross, wandering albatross, southern giant-petrel, northern giant petrel, soft-plumaged
petrel, Indian yellow-nosed albatross, Tasmanian shy albatross, white-capped albatross, Campbell
albatross, black-browed albatross, white-capped albatross.

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Species / Recovery plan / Key threats Relevant Conservation Actions

Sensitivity conservation advice (date identified in the
issued) recovery
plan/conservation
advice
Curlew Conservation advice Calidris Pollution / No explicit relevant management actions;
sandpiper ferruginea curlew sandpiper contamination pollution identified as a threat
(Threatened Species Scientific
Committee 2015f)
Eastern Conservation advice Numenius Pollution / No explicit relevant management actions;
curlew madagascariensis eastern contamination pollution identified as a threat
curlew (Threatened Species
Scientific Committee 2015g)
Abbott’s Approved Conservation Advice No threats identified None applicable
booby for Papasula abbotti (Abbott's
booby) (Threatened Species
Scientific Committee 2015h)
Great knot Conservation advice Calidris Habitat degradation / No explicit relevant management actions;
tenuirostris great knot modification habitat degradation/ modification
(Threatened Species Scientific identified as a threat
Committee 2016b)
Greater sand Approved Conservation Advice Habitat degradation / No explicit relevant management actions;
plover for Charadrius leschenaultii modification habitat degradation/ modification
(Greater sand plover) identified as a threat
(Threatened Species Scientific
Committee 2016c)
Lesser sand Approved Conservation Advice Habitat degradation / No explicit relevant management actions;
plover for Charadrius mongolus modification habitat degradation/ modification
(Lesser sand plover) identified as a threat
(Threatened Species Scientific
Committee 2016d)
Soft- Conservation advice Habitat degradation / No explicit relevant management actions;
plumaged Pterodroma mollis soft- modification habitat degradation/ modification
petrel plumage petrel (Threatened identified as a threat
Species Scientific Committee
2015i)
Bar-tailed Approved Conservation Advice Habitat degradation / No explicit relevant management actions;
godwit for Limosa lapponica baueri modification habitat degradation/ modification
(baueri) (Bar-tailed godwit (western identified as a threat
Alaskan) (Threatened Species
Scientific Committee 2016e)
Australian Approved Conservation Advice Habitat degradation / No explicit relevant management actions;
painted snipe on Rostratula australis modification habitat degradation/ modification
(Australian Painted Snipe) identified as a threat
(Threatened Species Scientific
Committee 2013)

7.2.8.2 Biologically Important Areas & Habitat Critical for the Survival of a Species
The Department of the Environment and Energy (now the Department of Agriculture,
Water and the Environment) have established a series of Biologically Important Areas
(BIAs) for regionally significant marine species (which are typically listed as threatened
under the EPBC Act). BIAs identify areas where biologically significant behaviours may
occur, such as nesting, breeding, migrating, foraging or resting. The collection of BIAs

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were developed by the DAWE during the development of bioregional plans utilising a
range of data, such as expert advice and published literature. BIAs are intended to
assist decision-making under the EPBC Act.
Habitats critical for the survival of several species of marine turtles were identified in
the Recovery Plan for Marine Turtles in Australia 2017-2027 (Commonwealth of
Australia 2017). Like BIAs, these critical habitats identify areas where biologically
significant behaviours may occur. Unlike BIAs, habitats critical for the survival of a
species receive specific protection under the EPBC Act. While BIAs do not receive
specific protection under the EPBC Act, the threatened and migratory species
associated with them are MNES and are protected under the EPBC Act.
A review of the Conservation Values Atlas identified that there are no BIAs or critical
habitats within the Operational Area. A number of BIAs and critical habitats occur within
the ZPI. These BIAs and critical habitats are summarised in Table 7-7. Refer to the
species-specific discussions in Sections 7.2.8.4 Marine Mammals, 7.2.8.5 Reptiles,
7.2.8.6 Sharks and Rays, and 7.2.8.7 Birds for further information.
Table 7-7: BIAs and Critical Habitats(*) within the ZPI nearest to Prelude

Common Name BIA Behaviour Distance from Prelude

(km)
Marine Mammals
Blue and pygmy blue Migration 78
whales
Foraging 132
Humpback whale Migration 145
Calving 145
Resting 145
Nursing 145
Migration (north and south) 327
Dugong Foraging (high density seagrass beds) 168
Foraging 176
Calving 176
Breeding 176
Nursing 176
Australian snubfin dolphin Foraging 187
Breeding 190
Foraging (high density prey) 190
Calving 190
Resting 190
Indo-Pacific humpback Foraging 190
dolphin
Calving 190
Breeding 190
Foraging (high density prey) 190
Significant habitat - unknown behaviour 247
Calving 190

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Common Name BIA Behaviour Distance from Prelude

(km)
Indo-Pacific/spotted Foraging 190
bottlenose dolphin
Breeding 239
Reptiles
Flatback turtle Inter-nesting buffer 268
Foraging 344
Nesting* 302
Inter-nesting 356
Mating 1,005
Migration corridor 1,005
Aggregation 1,114
Green turtle Nesting* 43
Foraging and inter-nesting buffer 23
Inter-nesting buffer 121
Inter-nesting 169
Mating 174
Migration corridor 1,005
Aggregation 1,114
Basking 1,130
Hawksbill turtle Foraging 141
Inter-nesting buffer 150
Nesting 169
Nesting* 971
Mating 1,005
Migration corridor 1,005
Inter-nesting 1,005
Loggerhead turtle Foraging 344
Inter-nesting buffer 986
Nesting 1,008
Nesting* 1,285
Inter-nesting 1,688
Olive ridley turtle Nesting – critical habitat* 177
Foraging 344
Sharks and Rays
Whale shark Foraging 33
Foraging (high prey density) 1,329
Dwarf sawfish Foraging 203
Nursing 416

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Common Name BIA Behaviour Distance from Prelude

(km)
Freshwater sawfish Pupping 416
Foraging 416
Nursing 433
Green sawfish Foraging 203
Pupping 454
Nursing 769
Birds
Red-footed booby Breeding 59
Greater frigatebird Breeding 59
Lesser frigatebird Breeding 60
Wedge-tailed shearwater Breeding 61
Foraging (in high numbers) 1,747
White-tailed tropicbird Breeding 68
Brown booby Breeding 118
Lesser crested tern Breeding 141
Little tern Resting 142
Breeding 245
Roseate tern Breeding 142
Resting 571
Fairy tern Breeding 991
Bridled tern Foraging (in high numbers) 1,747
Sooty tern Foraging 1,772
Little shearwater Foraging (in high numbers) 1,826
White-faced storm petrel Foraging (in high numbers) 1,837

7.2.8.3 Seasonal Sensitivities of Threatened Species

Periods of the year coinciding with key environmental sensitivities for the Operational
Area and the wider regional context (ZPI), including EPBC Act listed threatened and/or
migratory species potentially occurring within the Operational Area are presented in
Table 7-8. These relate to breeding, foraging or migration of the indicated fauna.

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Table 7-8: Key environmental sensitivities and indicative timings for migratory fauna within the Operational Area and ZPI (North-west Marine Region)

September

November

December
February
January

October
August
March

June
April

July
May
Species

Mammals
Blue whale1,2
Humpback whale3,4
Reptiles
Loggerhead turtle5 H H H N N H
Green turtle6,7 N,H N,H H H H N
Hawksbill turtle8 N,H H H N N N,H
Olive ridley turtle9
Flatback turtle10 N N N N N N N N
Birds
Migratory shorebirds11

Species likely to be present

Peak period. presence of animals reliable and predictable each year
N Peak Turtle Species Nesting
H Peak Turtle Species Hatching
1 - Commonwealth of Australia (2015a), 2 - Double et al. (2014), 3 - Jenner and Jenner (2001), 4 - Double et al. (2012a), 5 - Limpus (2008a), 6 - Limpus (2008b), 7 - Guinea (2010), 8 - Limpus (2009a), 9 -
Limpus (2008c), 10 - Limpus (2007), 11 - Rogers et al. (2011)

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7.2.8.4 Marine Mammals

Sei Whale
Sei whales (Balaenoptera borealis) have a global distribution. Though sightings are
uncommon, the species may be seen in coastal and offshore waters throughout
Australia, as well as the waters surrounding Christmas and Cocos Keeling Islands
(Bannister et al. 1996, DoEE 2019). The species utilises a range of marine habitats,
which has been attributed to a combination of dynamic physical and prey processes
(DoEE 2019).
Sei whale migratory movements are well defined (distinctly north-south) with the
species moving between polar, temperate and tropical waters for foraging and
breeding. The species feeds intensively between the Antarctic and sub-Antarctic
boundary on planktonic crustaceans (Bannister et al. 1996, DoEE 2019). The species
does not dive, rather it sinks, and tends to swim at shallower depths comparative to
other species (DoEE 2019).
There are no mating or calving areas in Australian waters, nor are there any
recognised BIAs or critical habitat. Sei whales may occur within the Operational Area
and ZPI, but are expected to occur only in low numbers.
Bryde’s Whale
The Bryde’s whale was identified as potentially occurring within the Operational Area
and ZPI. The Bryde’s whale occurs in tropical and temperate waters (Bannister et al.
1996). Bryde’s whales occur in both oceanic and inshore waters with the only key
localities recognised in Western Australia being in the Abrolhos Islands and north of
Shark Bay (Bannister et al. 1996). Two forms are recognised: inshore and offshore
Bryde’s whales. It appears that the offshore form may migrate seasonally, heading
towards warmer tropical waters during the winter, however, behaviour of the offshore
form in the Indian Ocean is not well documented.
Bryde’s whales may occur through a broad area of the continental shelf in the region,
including the Operational Area and the ZPI. The noise monitoring study undertaken for
the Barossa project detected Bryde’s whales in the Timor Sea almost year-round
(January to October) (McPherson et al. 2016). Bryde’s whales have also been detected
on the North West Shelf (south-west of the Operational Area) from mid-December to
mid-June, peaking in late February to mid-April (RPS Environment and Planning 2012).
Bryde’s whale may be encountered within the Operational Area and ZPI year-round in
low numbers, particularly in oceanic and continental slope waters.
Blue Whale
There are two recognised subspecies of blue whale in the Southern Hemisphere, both
of which are recorded in Australian waters. These are the southern (or 'true') blue
whale (Balaenoptera musculus) and the ‘pygmy' blue whale (Balaenoptera musculus
brevicauda) (Commonwealth of Australia 2015a). Both are listed as Endangered under
the EPBC Act. In general, southern blue whales occur in waters south of 60 °S and
pygmy blue whales occur in waters north of 55 °S (i.e. not in the Antarctic) (Department
of the Environment and Heritage 2005). On this basis, nearly all blue whales sighted
are likely to be pygmy blue whales. The Conservation Management Plan for the Blue
Whale (Commonwealth of Australia 2015a) has delineated the distribution area of blue
whales in Australian waters and identified a number of BIAs for blue whales for
Commonwealth waters (migratory corridor and foraging areas) (Table 7-8).

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Recent tagging studies (Double et al. 2014) indicate the general migration pattern,
timing and key areas for pygmy blue whales in Commonwealth waters are the Perth
Canyon/Naturaliste Plateau and Ningaloo Reef/North West Cape (beyond the ZPI).
Satellite tagging of pygmy blue whales off the Perth Canyon confirmed the general
distribution of migrating pygmy blue whales was offshore in water depths over 200 m
and commonly over 1,000 m (Double et al. 2012b). These data showed that whales
tagged during March and April migrated northwards post tag deployment. The tagged
whales travelled relatively near to the Australian coastline (100 ± 2 km) until reaching
North West Cape after which they travelled offshore (238 ± 14 km). Whales reached
the northern terminus of their migration and potential breeding grounds in Indonesian
waters by June (Double et al. 2014). The southbound migration is thought to terminate
in the Southern Ocean, where the species feeds.
No pygmy blue whale BIAs overlap the Operational Area; two BIAs were identified
within the ZPI (Table 7-8). These are:
• A broad migration corridor along the coast of Western Australia, approximately 78 km
west of the Prelude FLNG facility; and
• A potential foraging area around Scott Reef, approximately 132 km west of the Prelude
FLNG facility.

Based on these tagging studies and the locations of the BIAs relative to the
Operational Area, pygmy blue whales are unlikely to occur in the Operational Area due
to their preference for deeper waters, but are expected to be seasonally present within
the ZPI.

Figure 7-7: BIAs for blue and pygmy blue whales within the ZPI

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Fin Whale
Fin whales (Balaenoptera physalus) are widely distributed from polar to tropical waters
and have been recorded in all Australian states, other than New South Wales and the
Northern Territory (Bannister et al. 1996). The species is listed as Vulnerable under the
EPBC Act.
Fin whales are rarely observed in inshore waters and displays migratory movements
(essentially north-south) between polar, temperate and tropical waters (Bannister et al.
1996). Migration within Australian waters does not appear to follow a clear route and is
thought to occur in summer and autumn. Breeding in the Southern hemisphere occurs
in tropical and sub-tropical latitudes between May and July.
Fin whales feed on planktonic crustacea, such as Antarctic krill, and primarily forage in
high latitudes (Bannister et al. 1996). Within Australian waters, Antarctic waters and the
Bonney Upwelling are thought to be important foraging grounds for this species.
There are no recognised BIAs or critical habitats for fin whales within the Operational
Area or the ZPI. The species may occur within the Operational Area or ZPI, but is not
expected to be particularly abundant.
Humpback Whales
The humpback whale (Megaptera novaeangliae) has a wide distribution, with
recordings throughout Australian Antarctic waters and offshore from all Australian
states (Bannister et al. 1996). Humpback whales are listed as Vulnerable under the
EPBC Act.
Humpback whales migrate between summer feeding grounds in Antarctica and winter
breeding and calving grounds in the sub-tropical and tropical inshore waters of north-
west Australia (Jenner et al. 2001). Humpback whales breed and calve in continental
shelf waters off northern Western Australia, with the area between Broome and the
northern end of Camden Sound hosting large numbers of humpback whales from June
to September each year (Double et al. 2012a, 2010). Camden Sound is considered to
be the northern limit of most migrating humpback whales; hence the species is unlikely
to occur within the Operational Area but will be seasonally present within the ZPI.
Within the wider ZPI, a BIA area has been identified for the humpback whale. The
behaviour of the humpback whale within this BIA, located approximately 145 km south
of the Operational Area is resting, calving, migrating and nursing (Figure 7-8).

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Figure 7-8: BIAs for humpback whales within the ZPI

Killer Whale
Killer whales (Orcinus orca) have a global distribution and utilise a wide range of
habitats. However, they appear to be primarily concentrated in temperate coastal
waters and cooler regions of high productivity (Bannister et al. 1996).
This species is distributed throughout Australian waters, in particular in Tasmanian
waters and the waters surrounding Macquarie Island (1,500 km south-south-east of
Tasmania) (Bannister et al. 1996). Off Australia, the species is typically observed
moving along the continental slope and shelf, and near seal colonies (Bannister et al.
1996). There are no key localities identified within continental Australian waters for this
species. Killer whales are carnivores and their diet varies seasonally and regionally
(Bannister et al. 1996).
Globally killer whales are known to migrate; however, specific routes and seasonal
movement patterns are not known in detail and are thought to relate to prey availability
(Bannister et al. 1996). Mating occurs year-round and there are no known calving
areas in Australian waters (Bannister et al. 1996).
Based on their known distribution and movements, killer whales may be encountered in
within the Operational Area and ZPI in low numbers.
Sperm Whale
Sperm whales (Physeter microcephalus) occur in deep waters in all oceans, typically
remaining at depths of 200 m or greater, and are known to occur throughout Australian
waters (Bannister et al. 1996). Key areas for sperm whales occur in continental shelf
waters approximately 20 nautical miles (nm) to 30 nm offshore between Cape Leeuwin
and Esperance (Bannister et al. 1996), several thousand kilometres from the ZPI.

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Sperm whales have a diverse diet, although they primarily feed on oceanic squid
(Bannister et al. 1996). Migration patterns vary between sex. Mature females and
juveniles are thought to be resident in tropical and subtropical waters throughout the
year, whereas mature males are thought to migrate between the tropics and Antarctic
(Bannister et al. 1996).
Considering the known distribution of the species, sperm whales may transit through
the Operational Area and ZPI in low numbers.
Spotted Bottlenose Dolphin
The spotted bottlenose dolphin (Arafura/Timor Sea populations) (Tursiops aduncus)
occurs primarily in continental shelf waters (< 200 m deep), nearshore and in areas
with rocky or coral reefs, sandy or soft sediments, or seagrass beds (DSEWPaC
2012d). Small populations also occur in the inshore waters of some oceanic and
continental shelf islands, such as the Rowley Shoals and Scott Reef (DSEWPaC
2012d). No BIAs occur within the Operational Area. Several BIAs occur within the ZPI
(primarily within the Lalang-garram / Camden Sound Marine Park), including foraging
and calving (190 km south of Prelude) and breeding (239 km south of Prelude).
Migration patterns for the species in Australia are variable, including of year-round
residency in small areas, long-range movements and migration. Due to their tendency
to shallow water areas it is unlikely that the species will occur in the Operational Area,
but is likely to occur in coastal waters in the ZPI.
Antarctic Minke Whale
The Antarctic minke whale is distributed worldwide and has been recorded off all
Australian states, feeding in cold waters and migrating to warmer waters to breed. It is
not expected to occur in the Operational Area, but may occur within the ZPI. It is
thought that the Antarctic minke whale migrates up the WA coast to approximately
20°S to feed and possibly breed (Bannister et al. 1996); however, detailed information
on timing and location of migrations and breeding grounds is not well known. No critical
habitats or BIAs for Antarctic minke whales occur within the Operational Area or ZPI.
Given the wide distribution of Antarctic minke whale, the ZPI is unlikely to represent an
important habitat for this species. Antarctic minke whales are not expected to occur
within the Operational Area or ZPI in large numbers.
Dugong
Dugongs (Dugong dugong) occur in tropical and sub-tropical coastal and island waters
broadly coincident with the distribution of seagrasses (Marsh et al. 2002), which
typically occur in shallow intertidal zone areas to water depths of around 25 m. Dugong
feeding aggregations tend to occur in large seagrass meadows within wide shallow
protected bays, shallow mangrove channels and in the lee of large inshore islands. The
movements of most individuals are limited to within tens of kilometres within the vicinity
of seagrass beds (Marsh et al. 2002). However, some individuals have been observed
to travel large distances of up to 600 km over a few days (Marsh et al. 2002).
Dugongs and areas of potential dugong habitat exist along the majority of northern
Australian coastline from Shark Bay in Western Australia to Moreton Bay in
Queensland. A small population of approximately 50 individuals exists at Ashmore
Reef, which is considered to be genetically distinct from other nearby Australian or
Indonesian populations (Commonwealth of Australia 2002).
Several BIA’s for dugong overlap the ZPI, the nearest of which is the foraging (high
density seagrass beds BIA around Cartier Island approximately 168 km north of the

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Prelude FLNG facility. Other BIAs for foraging, breeding, calving and nursing occur
within the ZPI around Ashmore Reef and the Dampier Peninsula.
Considering the habitat preference of the species, dugongs are very unlikely to occur
within the Operational Area but are expected to occur in coastal waters and around
islands in the ZPI.
Southern Right Whale
The southern right whale occurs primarily in waters between approximately 20° and
60°S and moves from high latitude feeding grounds in summer to warmer, low latitude,
coastal locations in winter (Bannister et al. 1999). These latitudes are far to the south of
the Operational Area, which is at approximately 13.7°S. Southern right whales
aggregate in calving areas along the south coast of Western Australia, such as
Doubtful Island Bay, east of Israelite Bay and to a lesser extent Twilight Cove
(DSEWPaC 2012b). During the calving season, between May and November, female
southern right whales that are either pregnant or with calf can be present in shallow
protected waters along the entire southern Western Australian coast and west up to
approximately Two Rocks, north of Perth. Sightings in more northern waters are
relatively rare; however, they have been recorded as far north as Exmouth (Bannister
et al. 1996). There are no southern right whale BIAs within the Operational Area or ZPI.
Given the species prefers temperate waters and has rarely been recorded north of
Exmouth, southern right whales will not occur in the Operational Area and are very
unlikely to occur in the ZPI.
Australian Snubfin Dolphin
The Australian snubfin dolphin (Orcaella heinsohni, also known as the Irrawaddy
dolphin, O. brevirostris) shares similar habitat preferences with the Indo-Pacific
humpback dolphin, occurring in shallow coastal and estuarine waters (typically less
than 20 m deep) (DSEWPaC 2012d). However, as with the Indo-pacific humpback
dolphin, the species has also been recorded up to 23 km offshore. In Australia, the
species distribution covers the coastal waters of Queensland, the Northern Territory
and northern Western Australia. The population in Australian waters is thought to be
continuous with the Papua New Guinea species but separate from populations in Asia.
This species is not expected to occur within the Operational Area due to its preference
for coastal habitats, but may be present in coastal areas of the ZPI. No BIAs occur
within the Operational Area. Several BIAs occur within the ZPI (primarily within the
Lalang-garram / Camden Sound Marine Park), including foraging, breeding, resting and
calving (190 km south of Prelude).
Indo-Pacific (Australia) Humpback Dolphin
The Indo-Pacific humpback dolphin has been recognised as two distinct species; the
Indo-Pacific humpback dolphin (Sousa chinensis) and the Australian humpback dolphin
(S. sahulensis) (Jefferson and Rosenbaum 2014). Only the Australian humpback
dolphin is considered here. Humpback dolphins inhabit shallow coastal, estuarine
habitats in tropical and subtropical regions generally in depths of less than 20 m
(Corkeron et al. 1997, Jefferson 2000, Jefferson and Rosenbaum 2014).
The Australian humpback dolphin (Sousa sahulensis) occurs along the northern
Australian coastline from Exmouth in Western Australia to the Queensland/New South
Wales border (Bannister et al. 1996). The species’ preferred habitat is shallow
(generally < 20 m in depth) coastal, estuarine and riverine (occasional) waters.

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However, individuals have been observed in shallow waters up to 55 km offshore

(Bannister et al. 1996).
Given the species’ preferred habitat is relatively shallow coastal waters, Australian
humpback dolphins are very unlikely to occur in the Operational Area, but may be
present in coastal areas of the ZPI. There are several BIAs within the ZPI along the
Kimberley coast, including foraging, breeding, calving and resting, the closest of which
is approximately 190 km from the Prelude FLNG facility.
7.2.8.5 Reptiles
Loggerhead Turtle
The loggerhead turtle (Caretta caretta) is distributed throughout tropical and sub-
tropical and temperate waters in all ocean basis. In Australia, the species ranges along
most of the coastline, but is rare in temperate waters (Commonwealth of Australia
2017). Nesting in Australia is concentrated in southern Queensland and from Shark
Bay to the North West Cape in Western Australia. Foraging areas are more widely
distributed with the Western Australian stock foraging from Shark Bay through to
Arnhem Land, Gove and into the Java Sea of Indonesia (Limpus 2008a). Loggerhead
turtles are carnivorous and mainly feed on benthic invertebrates in a wide range of
habitats ranging from nearshore to 55 m in depth (Commonwealth of Australia 2017).
Loggerhead turtles may occur within the Operational Area and the ZPI. A foraging BIA
for the loggerhead turtle lies within the ZPI approximately 344 km east from the Prelude
FLNG facility. The nearest critical habitat for loggerhead turtles defined by the
Recovery plan for marine turtles in Australia 2017-2027 (Commonwealth of Australia
2017) is the nesting habitat around North West Cape, approximately 1,285 km south-
west from Prelude.
Green Turtle
The green turtle (Chelonia mydas) is distributed in tropical and sub-tropical waters in
the Pacific, Atlantic and Indian oceans. Within Australian waters, the species is
predominately found off the Western Australia, Northern Territory and Queensland
coastlines (Commonwealth of Australia 2017). The population at Ashmore Reef and
Cartier Island is thought to nest year-round, with a peak in nesting during December
and January; hatchling emergence is thought to be highest during May (Limpus
2008b).
The species is primarily herbivorous and forages on algae, seagrass and mangroves,
including where these habitats exist at offshore coral reef habitats (Commonwealth of
Australia 2017). Tagging studies have shown that green turtles can move considerable
distances between nesting, with movements of 100’s to 1,000’s of kilometres recorded
(Limpus 2008b).
No BIAs or habitats critical for the survival of green turtles overlap the Operational
Area. The nearest habitat critical for the survival of green turtles is the nesting habitat
around Browse Island; this habitat lies approximately 23 km south-east of the Prelude
FLNG facility at the closest point. Other critical nesting habitat within the ZPI is
distributed around offshore islands in the Timor Sea and along the Kimberley coast
(Figure 7-9). There are also a number of BIAs for green turtles within the ZPI, none of
which overlap the Operational Area:
• Foraging and inter-nesting buffer (23 km south-east of Prelude)
• Inter-nesting buffer (121 km north of Prelude)

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• Nesting (141 km north of Prelude FLNG facility)

• Inter-nesting (169 km west of Prelude FLNG facility)
• Mating (174 km north of Prelude FLNG facility).

Green turtles may occur throughout the Operational Area, but would only be expected
to occur in low numbers due to the absence of foraging or nesting habitat. Green turtles
may be present throughout the ZPI, and are likely to be more abundant around nesting
beaches and shallow foraging habitats.

Figure 7-9: Critical habitats for marine turtles within the ZPI

Leatherback Turtle
The leatherback turtle (Dermochelys coriacea) is distributed in tropical and temperate
oceans worldwide. The species is known to forage and migrate throughout the open
offshore waters of Australia, with a distribution that extends further south into
temperate waters than other marine turtle species (Limpus 2009b). Records of
leatherback turtle nesting in Australia are sparse and limited to the Cobourg Peninsula
and Queensland coast (Limpus 2009b). There have been no confirmed accounts of
nesting on beaches along Western Australia’s coastline. Leatherback turtles eat almost
exclusively jellyfish and are pelagic throughout their life in oceanic waters around
Australia (Limpus 2009b).
There are no BIAs or habitats critical for the survival of leatherback turtles within the
Operational Area and ZPI. Leatherback turtles may occur within the Operational Area
and ZPI in low numbers throughout the year.

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Hawksbill Turtle
The hawksbill turtle (Eretmochelys imbricata) has a worldwide distribution in tropical
and sub-tropical waters. In Australia, hawksbill turtles predominately occur along the
northern Western Australia, Northern Territory and northern Queensland coastlines
(Limpus 2009a).
This species is typically associated with rocky and coral reef habitats and is expected
to be found foraging within these habitats along the Western Australian coastline, from
Shark Bay to the northern extent of the North West Marine Region (Commonwealth of
Australia 2017a). Hawksbill turtles are omnivorous and feed on algae, sponges, soft
corals and soft bodied-invertebrates.
The population in Western Australia is thought to nest primarily between October and
January, while there is evidence of year-round breeding and nesting in the Northern
Territory and northern Queensland stocks (Limpus 2009a).
There are no habitats critical for the survival of hawksbill turtles within the Operational
Area or the ZPI. There are a number of BIAs for hawksbill turtles within the ZPI:
• Foraging (141 km north of Prelude FLNG facility)
• Inter-nesting buffer (150 km west of Prelude FLNG facility)
• Nesting (169 km west of Prelude FLNG facility).

Hawksbill turtles may occur throughout the Operational Area, but would only be
expected to occur in low numbers due to the absence of foraging or nesting habitat.
Hawksbill turtles may be present throughout the ZPI, and are likely to be more
abundant around nesting beaches and shallow foraging habitats.
Olive Ridley Turtle
The olive ridley turtle (Lepidochelys olivacea) has worldwide tropical and sub-tropical
distribution. In Australia, the species primarily occurs primary in the Northern Territory
and Queensland; the component of the Australian population in Western Australian
waters is relatively small (Limpus 2008c).
The olive ridley turtle is primarily carnivorous and feed predominantly on soft-bodied
invertebrates (Commonwealth of Australia 2017). The species is known to feed in
water depths between 15 m and 200 m, and may make movements > 1,000 km
between their nesting and foraging grounds (Whiting et al. 2007).
Nesting is known to occur in the Northern Territory and on western Cape York
(Queensland) (Commonwealth of Australia 2017, Limpus 2008c); low density nesting
has also been described on the Kimberley coast (Limpus 2008c).
No BIAs or habitats critical for the survival of the olive ridley turtle occur within the
Operational Area. Nesting habitat critical for the survival of the olive ridley turtle does
occur within the ZPI (Figure 7-9), centred on several islands along the Kimberley
coastline, the nearest of which is approximately 177 km south of Prelude. The nearest
olive ridley BIA to the Prelude FLNG facility is a foraging BIA, which lies approximately
344 km to the east.
Olive ridley turtles may occur within the Operational Area and the ZPI, but are only
expected to be present in low numbers.

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Flatback Turtle
The flatback turtle (Natator depressus) is known to occur along the Western Australia,
Northern Territory and Queensland coastlines, and forages widely across the
Australian continental shelf and into the continental waters off Indonesia and Papua
New Guinea (Commonwealth of Australia 2017). Unlike other species of marine turtle,
the flatback turtle does not have a global tropical distribution, with all recorded nesting
beaches within Australian waters (Limpus 2007).
Flatback turtles nest throughout tropical Australia, although there are several distinct
populations (Limpus 2007). The northerly populations in Queensland and the Northern
Territory nest year-round with a peak during winter months. Populations at higher
latitudes off central Queensland and Western Australia’s Pilbara coast tend to have a
nesting peak in summer (Limpus 2007).
Flatback turtles are primarily carnivorous and feed predominantly on soft-bodied
invertebrates in relatively shallow waters (Limpus 2007). Their distribution is largely
restricted to continental shelf waters (< 200 m).
There are no BIAs or habitats critical for the survival of flatback turtles within the
Operational Area. Habitat critical for the survival of flatback turtles does occur within
the ZPI, the closest of which is the inter-nesting habitat on the western Dampier
Peninsula, approximately 302 km south of the Prelude FLNG facility. There are several
BIAs within the ZPI, including:
• Inter-nesting buffer (268 km south of the Prelude FLNG facility)
• Foraging (344 km east of the Prelude FLNG facility)
• Inter-nesting (360 km south of the Prelude FLNG facility)
• Nesting (360 km south of the Prelude FLNG facility).

Flatback turtles are unlikely to occur within the Operational Area, but are expected to
occur within the ZPI, particularly in suitable foraging habitat in coastal waters and
around nesting beaches.
Short-nosed Seasnake
The short-nosed seasnake (Aipysurus apraefrontalis) is a slender marine snake with a
small head and pointed snout. This species has primarily been recorded at Ashmore
Reef and Cartier Island on the Sahul Shelf, which lie approximately 169 km north of the
Prelude FLNG facility. The species has also been recorded along the Pilbara coast
between Exmouth Gulf and Broome (Threatened Species Scientific Committee 2010a).
Like all seasnakes, the short-nosed seasnake must come to the surface to breathe at
intervals anywhere between 30 minutes and two hours. The species has been
recorded primarily in reef flats or in shallow waters (< 10 m). The short-nosed
seasnake has apparently experienced a decline in numbers, with recent surveys of
Ashmore Reef failing to observe the species (Threatened Species Scientific Committee
2010a).
The short-nosed seasnake is unlikely to occur within the Operational Area, but may
occur within shallow reef habitat within the ZPI.
Leaf-scaled Seasnake
The leaf-scaled seasnake (Aipysurus foliosquama) is a slender marine snake growing
up to 60 cm in total length with some specimens found up to 90 cm. Like the short-

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nosed seasnake, the leaf-scaled seasnake is thought to be largely restricted to the

reefs of the Sahul Shelf in Western Australia, especially on Ashmore and Hibernia
Reefs (Threatened Species Scientific Committee 2010b).
The short-nosed seasnake is unlikely to occur within the Operational Area, but may
occur within shallow reef habitat within the ZPI.
Saltwater Crocodile
The salt-water crocodile occurs within the nearshore marine and estuarine waters
throughout southern Asia and Northern Australia. Large populations within the major
river systems of the Kimberley occur in the rivers draining into the Cambridge Gulf, the
Prince Regent and Roe River systems of the east and northwest Kimberley. There are
no BIAs for the species within the Operational Area or ZPI. Saltwater crocodiles are
very unlikely to occur in the Operational Area, but may be present within the coastal
waters, estuaries and tidal creeks of the Kimberley region within the ZPI.
7.2.8.6 Sharks and Rays
Narrow Sawfish
The narrow sawfish is widely distributed throughout the Indo-Pacific region, with
records spanning from the Arabian Gulf to Japan. In Australia, the species may have a
broad tropical distribution from approximately North West Cape in Western Australia to
southern Queensland. Like other sawfish species, the narrow sawfish has experienced
considerable decline in numbers due to human activities, including fishing and habitat
loss / damage (Cavanagh et al. 2003).
Like other sawfish in the family Pristidae, the narrow sawfish prefers shallow coastal,
estuarine and riverine habitats, although may occur in waters up to 40 m deep
(D’Anastasi et al. 2013). There are no BIAs for this species within the Operational Area
or the ZPI. Given the water depth (>230 m) and distance from preferred habitats,
narrow sawfish are not expected to occur within the Operational Area. However, the
species may be found in shallow coastal waters and estuaries within the ZPI.
White Shark
The white shark (Carcharodon carcharias) has a circumglobal distribution primarily in
temperate waters. In Australian waters, the species typically occurs in temperate and
sub-tropical waters between the shore and the 100 m depth contour; however, adults
and juveniles have been recorded diving to depths of 1,000 m (Bruce 2008, Bruce et al.
2006). Tagging studies indicate white sharks may move as far north as Rockhampton
on the Queensland coast, however they are thought to be very uncommon in tropical
waters (Bruce et al. 2006), such as the Timor Sea.
There are no BIAs for white sharks within the Operational Area or ZPI; given the anti-
tropical distribution of this species, white sharks are unlikely to occur in the Operational
Area or ZPI.
Northern River Shark
The northern river shark (Glyphis garricki) is a medium-sized shark which can tolerate
both marine and freshwater. The species has a tropical distribution and is believed to
be endemic to northern Australia and southern New Guinea (Stevens et al. 2005). In
Western Australia, the majority of records of the species are from King Sound. The
species is most commonly encountered in tidal creeks and estuaries (Morgan et al.
2010), hence it is unlikely to occur within the Operational Area but may be present in

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Kimberley coastal waters in the ZPI. There are no BIAs for this species within the
Operational Area or ZPI.
Shortfin Mako
The shortfin mako shark is a pelagic species with a circumglobal, wide-ranging oceanic
distribution in tropical and temperate seas (Mollet et al. 2000). The shortfin mako is
commonly found in water with temperatures greater than 16 °C. Tagging studies
indicate shortfin makos spend most of their time in water less than 50 m deep but with
occasional dives up to 880 m (Abascal et al. 2011, Stevens et al. 2010).
The species can grow to almost 4 m in length. Females mature later (19 to 21 years)
than males (7 to 9 years) and adults have moderate longevity estimates of 28 to 29
years (Bishop et al. 2006).
The shortfin mako shark is an apex and generalist predator that feeds on a variety of
prey, such as teleost fish, other sharks, marine mammals and marine turtles (Campana
et al. 2005). Little is known about the population size and distribution of shortfin mako
sharks in Western Australia; they may occur in both the Operational Area and ZPI.
Longfin Mako
The longfin mako is a widely distributed, but rarely encountered, oceanic shark
species. The species can grow to just over 4 m long and is found in northern Australian
waters, from Geraldton in Western Australia to at least Port Stephens in New South
Wales and is uncommon in Australian waters relative to the shortfin mako (Bruce 2013,
Department of the Environment, Water, Heritage and the Arts 2010).
There is very little information about these sharks in Australia, with no available
population estimates or distribution trends. A study from southern California
documented juvenile longfin mako sharks remaining near surface waters, while larger
adults were frequently observed at greater maximum depths of about 200 m
(Sepulveda et al. 2004).
Longfin mako may occur in the Operational Area and ZPI, but given their widespread
distribution and apparent low density they are likely to be uncommon.
Giant Manta Ray
The giant manta ray is broadly distributed in tropical waters of Australia. The species
primarily inhabits near-shore environments along productive coastlines with regular
upwelling, but they appear to be seasonal visitors to coastal or offshore sites including
offshore island groups, offshore pinnacles and seamounts (Marshall et al. 2011). Giant
manta rays have been recorded regularly off the Ningaloo Coast (Preen et al. 1997),
well beyond the ZPI.
The Operational Area is not located in, or adjacent to, any known aggregation areas for
the species (e.g. feeding or breeding). Occurrence of giant manta rays within the
Operational Area is likely to be infrequent, and restricted to individuals transiting the
area.
Green Sawfish
The green sawfish (Pristis zijsron) were once widely distributed in coastal waters along
the northern Indian Ocean, although it is believed that northern Australia may be the
last region where significant populations exist (Stevens et al. 2005). Within Australia,
green sawfish are currently distributed from about Cairns in Queensland across
northern Australian waters to Broome in Western Australia (Threatened Species
Scientific Committee 2008b).

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Despite records of the species in deeper offshore waters, green sawfish typically occur
in the inshore fringe with a strong associated with mangroves and adjacent mudflat
habitats (Commonwealth of Australia 2015b, Stevens et al. 2005). Movements within
these preferred habitats is correlated with tidal movements (Stevens et al. 2008).
No BIAs for the green sawfish overlap the Operational Area. BIAs in the ZPI include
foraging (203 km south of Prelude) and pupping (294 km south of Prelude) BIAs along
the Kimberley coast to the south of the Operational Area. Given the habitat preferences
of the green sawfish, the species is unlikely to occur within the Operational Area, but is
likely to occur with the ZPI along nearshore waters and tidal creeks of the Kimberley
coastline.
Whale Shark
The whale shark (Rhincodon typus) is globally distributed in tropical and warm
temperate waters, and it is thought individuals form a single genetic population (Castro
et al. 2007). The species is an epipelagic filter feeder; their diet typically consists of
planktonic and nektonic species, including small crustaceans and smaller schooling
fish species.
Key areas of concentration within Australian waters include the Ningaloo coast (March
– July), Christmas Island (December – January) and the Coral Sea (November –
December), with the timing of the aggregations thought to be linked to seasonal
fluctuations in prey abundance (Threatened Species Scientific Committee 2015d).
Tagging, aerial and vessel surveys of whale sharks aggregating off the Ningaloo Coast
suggest that the group disperses widely. Satellite tracking has shown that the sharks
may follow three migration routes from Ningaloo (Meekan & Radford 2010, Wilson et
al. 2006):
• north-west, into the Indian Ocean
• directly north, towards Sumatra and Java
• north-east, passing through the NWS Province travelling along the shelf break and
continental slope.

These large scale movements are consistent with observations in other parts of the
world. Tagging studies in other parts of the world have recorded whale shark
movements > 13,000 km (Eckert and Stewart 2001).
Based on tagging studies, a foraging BIA has been defined for whale sharks which
extends along the continental slope between the Ningaloo Coast and the Timor Sea
(Figure 7-10). While listed as a foraging BIA, it is more likely to represent a migration
corridor for individual whale sharks moving between Indonesia and the Ningaloo Coast.
This BIA does not overlap the Operational Area, but does extend through the ZPI. The
whale shark is known to occur within the Operational Area, with crew onboard the
Prelude FLNG facility having observed the species. Whales sharks will also occur
within the ZPI.

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Figure 7-10: Whale shark foraging BIA within the ZPI

Grey Nurse Shark (West Coast Population)

The grey nurse shark (Carcharus taurus) has a broad distribution in inner continental
shelf waters, primarily in sub-tropical to cool temperate waters. The species occurs
primarily in south-west coastal waters between 20 and 140 m depth off Western
Australia (Chidlow et al. 2006). Grey nurse sharks have been documented as
aggregating in specific areas (typically reefs), however no clear aggregation sites have
been identified off Western Australia (Chidlow et al. 2006).
No BIAs for grey nurse sharks occur within the Operational Area or the ZPI. Given the
species’ preference for temperate waters, it is unlikely to occur within the Operational
Area or ZPI.
Porbeagle
The porbeagle is a species of lamnid shark found in temperate, sub-Arctic and sub-
Antarctic waters worldwide. The species can thermos-regulate physiologically, allowing
it to occupy cooler waters than other shark species. The porbeagle has a wide vertical
range within the water column, with tagging studies recording the species between the
surface and > 700 m water depth (Saunders et al. 2011). Given its preference for
cooler waters (Bruce 2013), the porbeagle is unlikely to be encountered within the
Operational Area, but may occur in the southern portion of the ZPI. There are no critical
habitats or BIAs for the porbeagle in the Operational Area or ZPI.
Reef Manta Ray
The taxonomy of the reef manta ray (Manta alfredi) was revised relatively recently, with
this species being recognised as distinct from the giant manta ray (M. birostris)
(Marshall et al. 2009). The species is occurs in inshore waters, but also found around

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offshore coral reefs, rocky reefs and seamounts (Marshall et al. 2009). In contrast to
the giant manta ray, long-term sighting records of the reef manta ray at established
aggregation sites suggest that this species is more resident in tropical waters and may
exhibit smaller home ranges, philopatric movement patterns and shorter seasonal
migrations than the giant manta ray (Deakos et al. 2011, Marshall et al. 2009). A
resident population of reef manta rays has been recorded at Ningaloo Reef, and the
species has been shown to have both resident and migratory tendencies in eastern
Australia (Couturier et al. 2011).
Reef manta rays may occur in the Operational Area, but is only expected to occur in
low numbers. The species is likely to be present in the ZPI where suitable habitat is
available (e.g. coastal waters and offshore reefs).
Dwarf Sawfish
The dwarf sawfish (Pristis clavata) is found in Australian coastal waters extending north
from Cairns around the Cape York Peninsula in Queensland to the Pilbara coast (Kyne
et al. 2013).
Dwarf sawfish typically inhabit shallow (2 to 3 m) silty coastal waters and estuarine
habitats, occupying relatively restricted areas and moving only small distances
(Stevens et al. 2008). Juvenile dwarf sawfish utilise estuarine habitats in north-western
Western Australia as nursery areas and migrate to deeper waters as adults (Thorburn
et al. 2008, Threatened Species Scientific Committee 2009). The majority of capture
locations for the species in Western Australia waters have occurred within King Sound
(beyond the ZPI) and the lower reaches of the major rivers that enter the sound,
including the Fitzroy, Mary and Robinson rivers (Morgan et al. 2010). Individuals have
also been recorded from Eighty Mile Beach, and occasional individuals have also been
taken from considerably deeper water by trawl fishers (Morgan et al. 2010).
Dwarf sawfish are very unlikely to occur within the Operational Area, but may be
present in coastal waters within the ZPI.
Freshwater Sawfish
The freshwater sawfish (Pristis pristis) inhabits both riverine and marine environments
in northern Australia. While primarily associated with rivers, tidal creeks and estuaries,
the freshwater sawfish has been recorded up to 100 km offshore (Commonwealth of
Australia 2015b).
In Western Australia, the species is known from riverine and coastal environments in
the Kimberley region. Riverine habitats are particularly important as pupping habitats.
The freshwater sawfish is very unlikely to occur within the Operational Area, but may
occur in coastal waters, estuaries and tidal creeks along the Kimberley coastline within
the ZPI.
7.2.8.7 Birds
The Operational Area may be visited by migratory and oceanic birds but does not
contain any emergent land that could be utilised as roosting or nesting habitat and
contains no known critical habitats (including feeding) for any species. Observations
onboard the Prelude FLNG facility indicate that seabirds and migratory shorebirds
opportunistically roost onboard the facility.
Threatened and migratory bird species that may occur within the Operational Area and
ZPI can broadly be classified into two groups – seabirds and migratory shorebirds. The
descriptions below of the species in Table 7-5 have been based on these groups.

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Seabirds
Seabirds are birds that are highly adapted to the marine environment. Characteristics
of many seabird species include webbed feet, dense water-resistant plumage that
protects birds from becoming soaked, a diet comprising marine biota (typically fish),
and nesting on offshore islands or inaccessible coastlines. Many seabird species
spend relatively little time on land and forage at sea for extended periods. Some
species may undertake long migrations; however, unlike migratory shorebirds, they do
not typically follow the East Asian-Australasian flyway.
Seabirds that may occur within the Operational Area and ZPI (Table 7-5) include:
• noddies:
o common noddy
o Australian lesser noddy.
• shearwaters:
o streaked shearwater
o flesh-footed shearwater
o wedge-tailed shearwater.
• terns:
o Caspian tern
o bridled tern
o roseate tern
o little tern
o Australian fairy tern
o crested tern.
• frigatebirds:
o lesser frigatebird
o great frigatebird
o Christmas island frigatebird.
• tropicbirds:
o white-tailed tropicbird
o Christmas Island white-tailed tropicbird
o red-tailed tropicbird.
• petrels:
o southern giant-petrel
o northern giant petrel
o soft-plumaged petrel.
• albatrosses:
o Amsterdam albatross
o southern royal albatross
o wandering albatross

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o Indian yellow-nosed albatross

o Tasmanian shy albatross
o white-capped albatross
o Campbell albatross
o black-browed albatross
o white-capped albatross.
• boobies:
o Abbott's booby
o masked booby
o brown booby
o red-footed booby.
• ospreys.

Many of the seabird groups listed, such as noddies, terns, frigatebirds, tropicbirds and
boobies above are typically found in tropical areas. These species may transiently
occur within the Operational Area, however they are more likely to occur in the vicinity
of offshore islands in the ZPI, such as Browse Island and Ashmore Reef, particularly
during breeding seasons.
Many of the seabird groups listed above have temperate or sub-Antarctic distributions,
such as shearwaters, petrels and albatrosses. These species are very unlikely to occur
within the Operational Area, although may be present in the southern portion of the
ZPI.
Migratory Shorebirds
Migratory shorebirds and wading birds include many species of birds that breed in
northern Asia during the northern hemisphere summer (particularly eastern Russia and
China) and migrate to Australasia during the southern hemisphere summer to feed.
Many of these species follow the East Asian-Australasian flyway and are protected by
migratory bird agreements between counties along this route, including Australia.
Migratory shorebirds typically do not nest within Australia, but do make extensive use
of wetland and coastal habitats as feeding and resting areas during their migration.
Several of these areas are listed under the Ramsar Convention and are protected
under the EPBC Act (Section 7.2.5).
Migratory shorebirds that may occur within the Operational Area and ZPI include:
• sandpipers, curlews, stints, knots and turnstones (genus Calidris):
o common sandpiper
o sharp-tailed sandpiper
o curlew sandpiper
o pectoral sandpiper
o broad-billed sandpiper
o wood sandpiper
o marsh sandpiper

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o Terek sandpiper
o eastern curlew
o whimbrel
o ruddy turnstone
o sanderling
o ruff (reeve)
o red-necked stint
o red knot
o great knot.
• shanks and tattlers:
o grey-tailed tattler
o common greenshank
o common redshank.
• plovers:
o double-banded plover
o greater sand plover
o lesser sand plover
o oriental plover
o pacific golden plover
o grey plover.
• godwits:
o bar-tailed godwit
o bar-tailed godwit (baueri)
o Northern Siberian bar-tailed godwit
o Black-tailed godwit.
• Oriental Pratincole
• Asian Dowitcher
• Australian Painted-snipe.

Many of the species listed above are closely related and within the family
Scolopacidae, and share very similar life histories. All of these migratory shorebird
species may transit through the Operational Area during migration. They are likely to
occur seasonally along coastlines, in estuaries and wetlands throughout the ZPI,
particularly Ramsar sites (Section 7.2.5).

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7.3 Socio-Economic Environment

7.3.1 Heritage

7.3.1.1 World Heritage Properties

There are no World Heritage properties within the Operational Area. Two World
Heritage properties occur within the far southern portion of the ZPI:
• the Ningaloo Coast (approximately 1,283 km south of Prelude)
• Shark Bay, Western Australia (approximately 1,651 km south of Prelude).

The Ningaloo Coast

The Ningaloo Coast World Heritage Area (WHA) includes North West Cape and the
Muiron Islands, and was inscribed, under criteria (vii) and criteria (x) by the World
Heritage Committee onto the World Heritage Register in June 2011. The statement of
Outstanding Universal Value for the Ningaloo coast was based on the natural criteria
and recognised the following:
• Criterion (vii): The landscapes and seascapes of the property are comprised of mostly
intact and large-scale marine, coastal and terrestrial environments. The lush and
colourful underwater scenery provides a stark and spectacular contrast with the arid and
rugged land. The property supports rare and large aggregations of whale sharks
(Rhincodon typus) along with important aggregations of other fish species and marine
mammals. The aggregations in Ningaloo following the mass coral spawning and
seasonal nutrient upwelling cause a peak in productivity that leads approximately 300-
500 whale sharks to gather, making this the largest documented aggregation in the
world.
• Criterion (x): In addition to the remarkable aggregations of whale sharks the Ningaloo
Reef harbours a high marine diversity of more than 300 documented coral species, over
700 reef fish species, roughly 650 mollusc species, as well as around 600 crustacean
species and more than 1000 species of marine algae. The high numbers of 155 sponge
species and 25 new species of echinoderms add to the significance of the area. On the
ecotone, between tropical and temperate waters, the Ningaloo Coast hosts an unusual
diversity of marine turtle species with an estimated 10,000 nests deposited along the
coast annually.
The dominant feature of the Ningaloo Coast WHA is Ningaloo Reef, the largest fringing
reef in Australia. Ningaloo Reef supports both tropical and temperate species of marine
fauna and flora and more than 300 species of coral (Department of Conservation and
Land Management 2005).
The Ningaloo Coast WHA is entirely overlapped by the Commonwealth Ningaloo
Australian Marine Park and State Ningaloo Marine Park and Muiron Islands Marine
Management Area; refer to Section 7.3.2 for further information on these marine
protected areas.
Shark Bay, Western Australia
The Shark Bay WHA includes Bernier Island, Dorre Island and Dirk Hartog’s landing
site. Shark Bay was inscribed under all four natural criteria (criterion vii, viii, ix, and x)
by the World Heritage Committee onto the World Heritage Register in 1991. The
statement of Outstanding Universal Value for the Shark Bay WHA was based on
natural criteria and recognised the following:

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• Stromatolites, in the hypersaline Hamelin Pool, which represent the oldest form of life on
earth and are comparable to living fossils.
• One of the few marine areas in the world dominated by carbonates not associated with
reef building corals.
• One of the largest seagrass meadows in the world, covering 103,000 ha, with the most
seagrass species recorded in one area.
• Marine fauna such as dugong, dolphins, sharks, rays, turtles, fish, and migratory
seabirds which occur in great numbers.
• The hydrologic structure of Shark Bay, altered by the formation of the Faure Sill and a
high evaporation, has produced a basin where marine waters are hypersaline (almost
twice that of seawater) and contributed to extensive beaches consisting entirely of
shells.
• The Wooramel Seagrass Bank is also of great geological interest due to the extensive
deposit of limestone sands associated with the bank, formed by the precipitation of
calcium carbonate from hypersaline waters.

The Shark Bay WHA is partially overlapped by the State Shark Bay Marine Park and
Hamelin Pool Marine Nature Reserve.
7.3.1.2 Commonwealth Heritage Places
The Commonwealth Heritage List is a list of Indigenous, historic and natural heritage
places owned or controlled by the Australian Government. The Operational Area is not
located in, or in the immediate surrounds of, any Commonwealth Heritage places.
There are a number of Commonwealth Heritage Places within the ZPI. These are listed
in Table 7-9, with a supporting summary of their key values as Commonwealth
Heritage Places.

Table 7-9: Commonwealth Heritage Places within the ZPI

Commonwealth Approximate Description

Heritage Place Distance from
Prelude (km)
Scott Reef and 155 Scott Reef is considered regionally important for the following
surrounds features:
• high diversity of marine fauna, including corals, fish and
marine invertebrates;
• physical characteristics of the reefs create environmental
conditions which are rare for shelf atolls, including clear
deep oceanic water and large tidal ranges that provide a
high physical energy input to the marine ecosystem;
• high representation of species not found in coastal waters
off WA and for the unusual nature of their fauna which has
affinities with the oceanic reef habitats of the Indo-West
Pacific, as well as the reefs of the Indonesian region; and
• important for scientific research and benchmark studies
into long term geomorphological and reef formation
processes due to the age of the reef and the
documentation of its geophysical and physical
environmental characteristics.

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Commonwealth Approximate Description

Heritage Place Distance from
Prelude (km)
Ashmore Reef 162 The Ashmore Reef National Nature Reserve protects
National Nature Ashmore Reef, a large platform reef with coral reefs, sand
Reserve flats and three vegetated islands. Specific values of this site
include:
• breeding and foraging habitat for marine turtles
• considered to have the world’s greatest abundance and
diversity of sea snakes
• habitat for 569 species of fish, 255 species of corals and
433 species of mollusc, as well as species not
previously recorded or rarely recorded in Australia
• an important seabird rookery and provides an important
staging/feeding area for many seabirds and migratory
shorebirds (Environment Australia 2002)
• breeding and feeding habitat for a small dugong
population (< 50 individuals).

Mermaid Reef – 535 Mermaid Reef is one of three reef systems, located 30 –
Rowley Shoals 40 km apart, which make up the Rowley Shoals. The shoal
consists of a reef flat roughly 500 to 800 m wide, shallow
back reefs and a large lagoon.
The Rowley Shoals have been described as the most
perfectly formed shelf atolls in Australian waters, and the
clear, deep water and large tidal range of the atolls are
considered rare environmental conditions for shoals. The
specific values of Mermaid Reef include:
• high diversity of marine reef fauna, including corals, fish
and marine invertebrates
• important area for sharks, marine turtles and toothed
whales, dolphins, tuna and billfish
• important resting and feeding site for migratory seabirds
• regionally significant due to the presence of many
species not found in inshore tropical waters of Northern
Australia, and species that are close to their
geographical ranges. Includes 216 species of fish, 39
species of mollusc and seven species of echinoderms
• considered a genetic stepping stone between the
Indonesian archipelago and reefs to the south.

Ningaloo Marine 1,304 The Ningaloo Marine Area – Commonwealth Waters lies
Area - within the Commonwealth waters section of the Ningaloo
Commonwealth Coast World Heritage Property – refer to Section 7.3.1.1
Waters World Heritage Properties for further information about the
environmental values within the Ningaloo Marine Area –
Commonwealth Waters.
HMAS Sydney II 1,877 The HMAS Sydney II and HSK Kormoran Shipwreck Sites
and HSK Kormoran Commonwealth Heritage Place covers the historic wrecks
Shipwreck Sites that resulted from a battle during the Second World War.
Both wrecks are located in over 2,000 m of water. The battle
between HMAS Sydney and HSK Kormoran resulted in the
largest single loss of life in Australian naval history.

7.3.1.3 National Heritage Places

The National Heritage List is Australia’s list of natural, historic and Indigenous places of
outstanding significance to the nation. There are no National Heritage properties in, or

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in the immediate surrounds of, the Operational Area. National Heritage Places in the
ZPI are described in Table 7-10.
Table 7-10: National Heritage Places within the ZPI

National Approximate Description

Heritage Place Distance from
Prelude (km)
The West Kimberley 171 The West Kimberley is known for its ancient geology,
Aboriginal culture, stunning landscapes, and biological
richness. The West Kimberley coastline includes a range of
landforms, including cliffs, rocky headlands, sandy beaches,
rivers, waterfalls and numerous islands located off the coast.
The West Kimberley holds extensive history of Aboriginal
people who have lived in the area for at least 40,000 years.
The West Kimberley also provides remnant habitats for many
native animals and plants which are now absent elsewhere
in Australia. Many of the national heritage values of the West
Kimberley are located away from the coastline will not
credibly be affected by the petroleum activities considered in
this EP.
Barrow Island and 1,097 Barrow Island and the Montebello / Barrow Islands Marine
the Montebello- Conservation Reserves are of national and international
Barrow Islands significance as a diverse region of high conservation value
Marine terrestrial and aquatic habitats, and high species diversity
Conservation and endemism.
Reserves Barrow Island hosts a range of terrestrial and subterranean
species that are unique, including species that are extinct, or
threatened with extinction, on mainland Australia.
The marine environment within the reserves has complex
bathymetry with many reefs and a diverse assemblage of
corals. Significant marine turtle nesting activity occurs on
sandy beaches throughout the reserves, including significant
flatback and green turtle rookeries.
The Ningaloo Coast 1,283 Refer to The Ningaloo Coast World Heritage Area
description in Section 7.3.1.1 World Heritage Properties
Shark Bay, Western 1,651 Refer to Shark Bay, Western Australia World Heritage Area
Australia description in Section 7.3.1.1 World Heritage Properties
HMAS Sydney II 1,877 Refer to HMAS Sydney II and HSK Kormoran Shipwreck
and HSK Kormoran Sites description in Section 7.3.1.3 National Heritage Places
Shipwreck Sites

7.3.1.4 Cultural Heritage

There are no known sites of Indigenous or European cultural significance within the
Operational Area. The Australian coastline and nearshore islands have a long history
of Indigenous occupation and host many culturally significant sites. The ZPI partially
overlaps parts of the Kimberley, Pilbara and Gascoyne coastlines, which host
numerous culturally significant sites, including sites that contribute to the national
heritage value of the West Kimberley National Heritage Place.
7.3.1.5 Underwater Cultural Heritage
Information on underwater cultural heritage, including historic shipwrecks, is
maintained in the Australasian Underwater Cultural Heritage Database, a searchable
database of records provided by the Australian DAWE. A search of the database

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revealed no known shipwrecks or other underwater cultural heritage sites within the
Operational Area. The nearest historic shipwreck is the wreck of the sailing vessel
Berteaux, which lies approximately 18 km south-east of the Prelude FLNG facility.

7.3.2 Marine Protected Areas

The Operational Area does not overlap any Marine Protected Areas (MPAs), such as
Commonwealth Australian Marine Parks (AMPs) or state marine parks. There are a
number of Commonwealth AMPs and Western Australian MPAs in the ZPI (Figure
7-11) Each of these MPAs is described in Table 7-11.
All AMPs and many state MPAs have management plans in place, which outline the
objectives for the management of the protected area. These objectives have been
considered where applicable in the environmental impact and risk assessment in
Section 9.13.

Figure 7-11: Commonwealth and State Marine Protected Areas within the ZPI

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Table 7-11: MPAs within the ZPI

Marine Protected Distance from Prelude Description

(km)
Commonwealth AMPs
Kimberley 111 The Kimberley AMP covers approximately 74,469 km2 and ranges in water depth from less than 15 m to approximately 800 m.
The AMP lies from the Lacepede Islands in the north to the Holothuria Banks offshore from Cape Bougainville. The Kimberley
AMP contains the following conservation values (Director of National Parks 2018a):
• Important foraging areas for migratory seabirds, dugongs, dolphins and marine turtles
• Important migration pathway and nursery areas for the humpback whale
• Adjacent to important foraging and pupping areas for sawfish and important nesting sites for green turtles
• Features such as the continental shelf, slope, plateau, pinnacles, terraces, banks and shoals and deep holes/valleys
• Examples of the communities and seafloor habitats of the Northwest Shelf Transition, North West Shelf province and Timor
Province provincial bioregions along with the Kimberley, Canning, Northwest Shelf and Oceanic Shoals meso-scale
bioregions.
The AMP provides protection for two KEFs; an ancient coastline (a unique seafloor feature that provides areas of enhanced
productivity) and continental slope demersal fish communities (the second richest area for demersal fish species in Australia),
refer to Section 7.2.3. The Kimberley meso-scale bioregion in particular has been reported to be one of the most diverse coral
areas in WA. In addition, the reserve is adjacent to the listed West Kimberley National Heritage place and Western Australian
Lalang-garram / Camden Sound Marine Park.
Cartier Island 134 Cartier Island AMP is considered to be a biodiversity hotspot (like nearby Ashmore Reef) and is thought to be a source of
larvae of marine biota such as corals which are transported south by the Leeuwin Current. The AMP covers an area of
approximately 172 km2. Key conservation values include (Director of National Parks 2018a):
• An unvegetated sand island
• High diversity and abundance of hard and soft corals, gorgonians, sponges and a range of encrusting organisms
• Algae and seagrasses
• Important breeding and foraging habitat for seabirds
• Foraging habitat for whale sharks
• Nesting, inter-nesting and foraging habitat for marine turtles
• High diversity and abundance of seasnakes.

Ashmore Reef 162 The Ashmore Reef AMP covers an area of 583 km2 and is a designated Ramsar Wetland (Section 7.2.5). Key conservation
values of the AMP include (Director of National Parks 2018a):

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Marine Protected Distance from Prelude Description

(km)
• Regionally significant as contains ecosystems, habitat and communities representative of the NWS, Timor Province and
emergent oceanic reefs
• Biologically rich habitat including primary producer habitat (mangroves, seagrass beds and coral reefs) and their associated
benthic communities, fishes and other biota
• Regionally important nesting, inter-nesting, foraging areas for marine turtles (particularly green but also hawksbill and
loggerhead turtles). An estimated 11,000 marine turtles feed in the area throughout the year
• Isolated, small dugong population of less than 50 individuals that breeds and feeds around the reef. This population is
thought to be genetically distinct from other Australian populations
• Important seabird rookeries and staging points/feeding areas for migratory sea/shorebirds including colonies of bridled terns,
common noddies, brown boobies, eastern reef egrets, frigatebirds, tropicbirds, red-footed boobies, roseate terns, crested
terns and lesser crested terns
• International significance for seasnake abundance and diversity
• Importance cultural and heritage sites: Indonesian artefacts and grave sites.

Oceanic Shoals 321 The Oceanic Shoals AMP comprises a 71,743 km2 area, with a large proportion (39,964 km2) designated as Multiple Use Zone
(IUCN Category VI). There are smaller areas designated for National Park Zone (Category II, 406 km2), Habitat Protection
Zone (Category IV, 6,929 km2), and Special Purpose Zone for Trawling (Category VI, 10,461 km2).
The AMP has several conservation values (Director of National Parks 2018a):
• important inter-nesting area for the flatback and olive ridley turtles
• an important foraging area for loggerhead and olive ridley turtles
• examples of the ecosystems of both the Northwest Shelf Transition and Timor Transition provinces.
KEFs represented in the reserve are carbonate banks, pinnacles and the shelf break and slope of the Arafura Shelf. (Refer to
Section 7.2.3.)
Argo-Rowley Terrace 323 The Argo-Rowley Terrace AMP covers 146,099 km2 of the MPA network, including the Commonwealth waters surrounding the
Rowley Shoals (each reef managed as separate state and Commonwealth marine parks). The Argo-Rowley Terrace
Commonwealth Marine Park encompasses water depths from approximately 220–6000 m.
The ecological and conservation values include (Director of National Parks 2018a):
• Important foraging areas for migratory seabirds and, reportedly, the loggerhead turtle
• Support for relatively large populations of sharks (compared with other areas in the region)
• A range of seafloor features such as canyons, continental rise and the terrace, among others
• Connectivity between the reefs of the Rowley Shoals

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Marine Protected Distance from Prelude Description

(km)
• Linkage of the Argo Abyssal Plain with the Scott Plateau through canyons.
The AMP is contiguous with the Western Australian Rowley Shoals Marine Park.
Roebuck 480 The Roebuck Marine Park is located approximately 12 km offshore of Broome, and is adjacent to the Western Australian
Yawuru Nagulagun/Roebuck Bay Marine Park. The Marine Park covers an area of 304 km² and a water depth range of less
than 15 m to 70 m.
The ecological and conservation values include (Director of National Parks 2018a):
• The park is adjacent to the Eighty Mile Beach Ramsar wetland
• Representative ecosystems of the Northwest Shelf Province
• Breeding and resting habitat for seabirds
• foraging and inter-nesting habitat for marine turtles
• migratory pathway for humpback whales
• foraging habitat for dugong.

Mermaid Reef 523 The Mermaid Reef Commonwealth Marine Park encompasses Mermaid Reef and covers 540 km2; it is classified as an IUCN
protected area category 1a, Sanctuary Zone (Strict Nature Reserve).
Mermaid Reef is one of the best geological examples of a shelf-edge reef in Australian waters (one of three oceanic reefs that
form the Rowley Shoals). It is the only reef of the Rowley Shoals located entirely in Commonwealth waters.
Mermaid Reef supports (Director of National Parks 2018a):
• rich coral communities (216 species of hard coral, 12 genera of soft corals)
• a high diversity of associated sessile and mobile invertebrates (echinoderms, molluscs and crustaceans)
• more than 390 reef and pelagic fish species
• a variety of sharks that frequent the reef habitats.
The Mermaid Reef AMP also includes the Mermaid Reef and Commonwealth Waters surrounding Rowley Shoals KEF (Table
7-3).
Joseph Bonaparte Gulf 604 The Joseph Bonaparte Gulf Marine Park is located approximately 15 km west of Wadeye, Northern Territory, and
approximately 90 km north of Wyndham, Western Australia, in the Joseph Bonaparte Gulf. It is adjacent to the Western
Australian North Kimberley Marine Park. The Marine Park covers an area of 8,597 km² and water depth ranges between less
than 15 m and 100 m (Director of National Parks 2018b).
Environmental values within the Park include (Director of National Parks 2018b):
• species and communities associated with the Northwest Shelf Transition bioregion

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Marine Protected Distance from Prelude Description

(km)
• carbonate bank and terrace system of the Sahul Shelf KEF
• prominent shallow seafloor features, including emergent reef, shoals and sand banks
• biologically important areas including foraging habitat or marine turtles and the Australian snubfin dolphin.

Eighty Mile Beach 788 Eighty Mile Beach AMP comprises a 10,785 km2 Multiple Use Zone. Environmental values within the AMP include (Director of
National Parks 2018a):
• examples of ecosystems representative of the Northwest Shelf Province
• diverse benthic and pelagic fish communities
• and ancient coastline thought to be an important seafloor feature and migratory pathway for humpback whales
• a range of fauna threatened, migratory, marine and cetacean under the EPBC Act.
The AMP is adjacent to the Eighty Mile Beach Ramsar wetland (which is beyond the ZPI).
Dampier 950 The Dampier Marine Park is located approximately 10 km north-east of Cape Lambert and 40 km from Dampier extending
from the Western Australian state water boundary. The Marine Park covers an area of 1,252 km² and a water depth range
between less than 15 m and 70 m (Director of National Parks 2018a).
Environmental values within the Park include (Director of National Parks 2018b):
• representative ecosystems and communities of the Northwest Shelf Province
• breeding and foraging habitat for seabirds
• inter-nesting habitat for marine turtles
• migratory pathway for humpback whales.

Montebello 1,047 The Montebello Marine Park is located offshore of Barrow Island and 80 km west of Dampier extending from the Western
Australian state water boundary, and is adjacent to the Western Australian Barrow Island and Montebello Islands Marine
Parks. The Marine Park covers an area of 3,413 km² and water depths from less than 15 m to 150 m (Director of National
Parks 2018a).
Environmental values within the Park include (Director of National Parks 2018b):
• habitats, species and ecological communities associated with the Northwest Shelf Province
• ancient coastline at the 125 m depth contour KEF
• breeding habitat for seabirds
• inter-nesting, foraging, mating and nesting habitat for marine turtles
• migratory pathway for humpback whales
• foraging habitat for whale sharks.

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Gascoyne 1,277 The Gascoyne Marine Park is located approximately 20 km off the west coast of the Cape Range Peninsula, adjacent to the
Ningaloo Reef Marine Park and the Western Australian Ningaloo Marine Park, and extends to the limit of Australia’s exclusive
economic zone. The Marine Park covers an area of 81,766 km² and water depths between 15 m and 6,000 m (Director of
National Parks 2018a).
Environmental values within the Park include (Director of National Parks 2018b):
• four KEFs:
- canyons linking the Cuvier Abyssal Plain and the Cape Range Peninsula
- Commonwealth waters adjacent to Ningaloo Reef
- continental slope demersal fish communities
- the Exmouth Plateau.
• diverse continental slope habitats
• breeding habitat for seabirds
• inter-nesting habitat for marine turtles
• migratory pathway for humpback whales
• foraging habitat and migratory pathway for pygmy blue whales.

Ningaloo 1,304 The Ningaloo Marine Park stretches approximately 300 km along the west coast of the Cape Range Peninsula, and is adjacent
to the Western Australian Ningaloo Marine Park and Gascoyne Marine Park. The Marine Park covers an area of 2,435 km²
and a water depth range of 30 m to more than 500 m (Director of National Parks 2018a).
Environmental values within the Park include (Director of National Parks 2018b):
• representative ecosystems of the:
- Central Western Shelf Transition
- Central Western Transition
- Northwest Province
- Northwest Shelf Province.
• KEFs:
- canyons linking the Cuvier Abyssal Plain and the Cape Range Peninsula
- Commonwealth waters adjacent to Ningaloo Reef
- continental slope demersal fish communities
• breeding habitat for seabirds
• inter-nesting habitat for marine turtles
• migratory pathway for humpback whales
• foraging habitat and migratory pathway for pygmy blue whales
• breeding, calving, foraging and nursing habitat for dugong

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• foraging habitat for whale sharks.

Shark Bay 1,588 The Shark Bay Marine Park is located approximately 60 km offshore of Carnarvon, adjacent to the Shark Bay world heritage
property and national heritage place. The Marine Park covers an area of 7,443 km², extending from the Western Australian
state water boundary, and a water depth range between 15 m and 220 m (Director of National Parks 2018a).
Environmental values within the Park include (Director of National Parks 2018b):
• representative ecosystems of the Central Western Shelf and Central Western Transition bioregions
• connectivity between deeper Commonwealth waters and inshore waters of Shark Bay
• breeding habitat for seabirds
• inter-nesting habitat for marine turtles
• migratory pathway for humpback whales.
The Park is adjacent to the Shark Bay World Heritage Area.
Abrolhos 1,781 The Abrolhos Marine Park is located adjacent to the Western Australian Houtman Abrolhos Islands, covering a large offshore
area extending from the Western Australian state water boundary to the edge of Australia’s exclusive economic zone. It is
located approximately 27 km south-west of Geraldton and extends north to approximately 330 km west of Carnarvon. The
northernmost part of the shelf component of the Marine Park, north of Kalbarri, is adjacent to the Shark Bay World Heritage
Area. The Marine Park covers an area of 88,060 km² and a water depth range between less than 15 m and 6,000 m (Director
of National Parks 2018c).
Environmental values within the Park include (Director of National Parks 2018c):
• KEFs:
- Commonwealth marine environment surrounding the Houtman Abrolhos Islands
- demersal slope and associated fish communities of the Central Western Province
- mesoscale eddies
- Perth Canyon and adjacent shelf break, and other west-coast canyons
- western rock lobster
- ancient coastline between 90 m and 120 m depth
- Wallaby Saddle.
• high biodiversity due to the southwards flowing Leeuwin Current supplying tropical species
• foraging and breeding habitat for seabirds
• foraging habitat for Australian sea lions and white sharks
• migratory pathway for humpback and pygmy blue whales.

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The Marine Park is adjacent to the northernmost Australian sea lion breeding colony in Australia on the Houtman Abrolhos
Islands.
Western Australian Marine Parks
Lalang-garram / Camden 182 The Lalang-garram / Camden Sound Marine Park provides protection for a large, biologically diverse part of the Kimberley
Sound coastal waters. The park is contiguous with the Commonwealth Kimberley AMP, which is described above. The environmental
and social values within the park include:
• habitat for a range of marine species, including marine turtles, coastal dolphins and dugong
• important calving and resting areas for humpback whales
• sanctuary zones which prohibit most activities, including fishing
• important cultural heritage sites for the traditional owners.
The Lalang-garram / Camden Sound Marine Park is jointly managed by WA government agencies and the traditional owners
of the land.
North Kimberley 188 The North Kimberley Marine Park covers an area of approximately 1,845,000 hectares, which is currently zoned as IUCN
Category VI – multiple use. The park is remote and contains a range of outstanding natural and cultural values, such as a
complex coastline with many small islands and cultural heritage sites for Aboriginal saltwater people.
The Marine Park contains habitats such as coral reefs, seagrasses and mangroves. Fauna include dugong, birds, marine
turtles, fishes, cetaceans and saltwater crocodiles.
Rowley Shoals 567 The Rowley Shoals Marine Park protects two of the three oceanic shoals (Clerke Reef and Imperieuse Reef) that constitute
the Rowley Shoals. The third shoal (Mermaid Reef) is protected by the Argo-Rowley Terrace AMP. The Rowley Shoals Marine
Park is characterised by intertidal and subtidal coral reefs, with rich and diverse marine fauna and high water quality. The reefs
within the park may act as a source of recruits for habitats further south, via the Leeuwin Current, and hence are considered to
be regionally significant (MPRA 2007).
Eighty Mile Beach Marine 612 Eighty Mile Beach is an extensive stretch of remote and remarkable coastal country located between Port Hedland and
Park Broome, stretching for some 220 km from Cape Missiessy to Cape Keraudren. The marine park includes Eighty Mile Beach,
Cape Keraudren and the diverse marine environments west of Cape Keraudren to Mulla Down Creek. it is jointly managed
with the traditional owners of the area (Department of Parks and Wildlife 2014).
The marine park contains vast intertidal sand and mudflats that extend up to 4 km wide at low tide and provide a rich source of
food for many species. Eighty Mile Beach is one of the world’s most important feeding grounds for migratory shorebirds and is
a major nesting site for flatback turtles, which are only found in northern Australia. Both are critical components of the Eighty
Mile Beach Ramsar site, and the management plan seeks to maintain its ecological character (Department of Parks and
Wildlife 2014).

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The Park is adjacent to the Commonwealth Eighty Mile Beach AMP.
Montebello Islands 1,097 The Montebello Islands Marine Park, Barrow Island Marine Park and Barrow Island Marine Management Area are jointly
Marine Park/Barrow managed and cover a combined area of 1,770 km2, located approximately 170 km from the Operational Area at the closest
Island Marine point. A sanctuary zone covers the entire 4,100 ha Barrow Island Marine Park. The Barrow Island Marine Management Area
covers 114,500 ha and includes most of the waters surrounding Barrow Island and Lowendal Islands, except for the port areas
Park/Barrow Island around Barrow and Varanus Islands. Key conservation and environmental values within the reserves include (Department of
Marine Management Area Environment and Conservation 2007):
• a complex seabed and island topography consisting of subtidal and intertidal reefs, sheltered lagoons, channels, beaches,
cliffs and rocky shores
• pristine sediment and water quality, supporting a healthy marine ecosystem
• undisturbed intertidal and subtidal coral reefs and bommies with a high diversity of hard corals
• important mangrove communities, particularly along the Montebello Islands, which are considered globally unique as they
occur in offshore lagoons
• extensive subtidal macroalgal and seagrass communities
• important habitat for cetaceans and dugongs
• nesting habitat for marine turtles
• important feeding, staging and nesting areas for seabirds and migratory shorebirds
• rich finfish fauna with at least 456 species
• historical culture of the pearl oyster (Pinctada maxima) in the reserves produces some of the highest quality pearls in the
world.
These islands support significant colonies of wedge-tailed shearwaters and bridled terns. The Montebello Islands support the
biggest breeding population of roseate terns in Western Australia. Ospreys, white-bellied sea-eagles, eastern reef egrets,
Caspian terns, and lesser crested terns also breed in this area.
The Montebello Islands Marine Park/Barrow Island Marine Park/Barrow Island Marine Management Area is contiguous with
the Montebello Commonwealth Marine Park.
Muiron Islands Marine 1,283 The Ningaloo Marine Park (State waters) was established in 1987 and stretches 300 m from the North West Cape to Red
Management Area and Bluff. It encompasses the State waters covering the Ningaloo Reef system and a 40 m strip along the upper shore. The Muiron
Ningaloo Marine Park Islands Marine Management Area is managed under the same management plan as for the Ningaloo State Marine Park
(Department of Conservation and Land Management 2005). The Ningaloo Marine Park is part of the Ningaloo Coast WHA.
Ecological and conservation values of the Ningaloo Marine Park and Muiron Islands are summarised below.
The ecological and conservation values include (Department of Conservation and Land Management 2005):
• Unique geomorphology, which has resulted in a high habitat and species diversity

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• High sediment and water quality
• Subtidal and intertidal coral reef communities providing food, settlement substrate and shelter for marine flora and fauna
• Filter feeding communities (sponge gardens) in the northern part of the North West Cape and the Muiron and Sunday
Islands
• Soft sediment communities found in deeper waters, characterised by a surface film of microorganisms that provide a rich
source of food for invertebrates
• Macroalgae and seagrass communities, which are an important primary producer providing habitat for vertebrate and
invertebrate fauna
• Diverse fish fauna (approximately 460 species)
• Foreshores and nearshore reefs of the Ningaloo coast and Muiron/Sunday islands provide inter-nesting, nesting and
hatchling habitat for several species of marine turtles including the loggerhead, green, flatback and hawksbill turtles
• Whale sharks aggregate annually to feed in the waters around Ningaloo Reef
• Nesting and foraging habitat for seabirds and shorebirds.

Shark Bay Marine Park 1,691 The Shark Bay Marine Park was gazetted in 1990 as an A Class Marine Park Reserve and encompasses and area of
7,487 km2. The values of the Marine Park are consistent with those of the World Heritage Area, which are described in Section
7.3.1.1 World Heritage Properties.

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7.3.3 Fishing Industry

7.3.3.1 Traditional Fishing

In 1974, Australia recognised access rights for traditional Indonesian fishers in shared
waters to the north of Australia, granting long-term fishing rights in recognition of the
long history of traditional Indonesian fishing in the area. A Memorandum of
Understanding (MOU) between the Governments of Australia and Indonesia enables
Indonesian traditional fishers to continue their customary practices. This area is known
as the ‘MOU Box’ and the Operational Area lies within it.
This MOU box covers Scott Reef and surrounds, Seringapatam Reef, Browse Island,
Ashmore Reef and Cartier Island, representing an area of approximately 50,000 km2.
Trochus, sea cucumbers (holothurians), abalone, green snail, sponges, giant clams
and finfish, including sharks, are targeted by the fishers. Given the shallow water target
species, these traditional Indonesian fishermen are only likely to be found in deep
water areas during transit to and from the reef locations.
7.3.3.2 Recreational Fishing
Currently, there are no known recreational fishing activities in the Operational Area as
the site is too far from shore to be accessed by recreational fishermen in small boats.
Even at relatively high speed (30 km/hour), it would take at least fifteen hours for a
recreational boat to reach the project area from the nearest port of Broome.
Recreational fishing, particularly boat-based angling, occurs throughout the ZPI.
Recreational angling is expected to be centred around access nodes, such as marinas
and boat launching facilities, found at towns across the Kimberley region. Recreational
anglers typically target demersal and pelagic fish species for consumption and sport.
7.3.3.3 Commonwealth Fisheries
Commonwealth fisheries that overlap the Operational Area and ZPI are described in
Table 7-12.

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Table 7-12: Commonwealth fisheries within the ZPI

Fishery Name Distance from Description

Prelude (km)

North-west slope trawl 0 The North West Slope Trawl Fishery extends from 114°E to 125°E, from the 200 m isobath to the outer limit of the
fishery Australian exclusive economic zone (EEZ). The fishery traditionally targets scampi and deep-water prawns. Fishing for
scampi occurs over soft, muddy sediments or sandy habitats, typically at depths of 200–400 m using demersal trawl gear
on the continental slope.
Activity in the fishery commenced in 1985, peaking at 21 active vessels in 1986-87 (Woodhams and Bath 2017). There are
currently very few licence holders active in the fishery and fishing activity has steadily declined since establishment of the
fishery. Two vessels operated in the fishery in the 2016-17 season, which is the same as the 2015-16 season. The total
area of waters fished in 2016-17 did not include the Operational Area.

Southern bluefin tuna 0 The Southern Bluefin Tuna Fishery is not active within Operational Area or the ZPI; all activity in this fishery occurs well
fishery south of the ZPI, primarily off South Australia. As such, the Southern Bluefin Tuna Fishery is not discussed further.

Western tuna and 0 The West Tuna and Billfish Fishery is currently active, running throughout the year. The fishery zoning extends to the
billfish fishery Australian EEZ boundary in the Indian Ocean, overlapping the Operational Area. The fishery targets four pelagic species,
which are all highly mobile:
• broadbill swordfish (Xiphias gladius)
• bigeye tuna (Thunnus obesus)
• yellowfin tuna (T. albacares)
• albacore tuna (T. alalunga).
The methods used by the fishery are mainly pelagic longline and some minor-line. The number of vessels operating in the
fishery has declined in recent years, with less than five vessels operating in the fishery since 2005 (Williams et al. 2017).
Effort data shows fishing effort is concentrated off south-west Western Australia and South Australia (Williams et al. 2017).

Skipjack fishery 0 The combined western and eastern skipjack tuna (Katsuwonus pelamis) fisheries encompass the entire EEZ, including the
Operational Area. The target species has historically been used for canning, and with the closure of canneries at Eden and
Port Lincoln effort in the fishery has declined and there have been no active vessels operating since 2009 (Patterson &
Bath 2017).

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Given the fishery has been inactive for a number of years and given the distribution of fishing effort when the fishery was
active, fishing for skipjack tuna in the Operational Area is highly unlikely. Should the fishery commence efforts in the area in
the future, fishing effort in the Operational Area is unlikely given the historical fishery was concentrated off southern
Australia.

Northern prawn fishery 395 The Northern Prawn Fishery is located off Australia’s northern coast from Cape York, Queensland to Cape Londonderry,
Western Australia. It is Australia’s second most valuable Commonwealth fishery. The fishery targets six species of prawn:
• Red-legged banana prawn (Penaeus indicus and P. merguiensis)
• White banana prawn (Fenneropenaeus merguiensis)
• Brown tiger prawn (P. esculentus)
• Grooved tiger prawn (P. semisulcatus)
• Blue endeavour prawn (Metapenaeus endeavouri)
• Red endeavour prawn (M. ensis).
The fishery method is bottom trawling during two seasons – April to June and August to November, with the season end
dates depending on the catch rates. In 2017, there were 52 vessels with fishing rights, which is the maximum number of
vessels active at one time. The Northern Prawn Fishery management area is located approximately 433 km from the
Operational Area.

Western deepwater 1,072 The Western Deepwater Trawl Fishery is permitted to operate only in deep waters from the 200 m isobath, as far north as
trawl fishery the North West Cape. This fishery targets a number of deep water demersal finfish and crustacean species. The nominated
fishing grounds are extensive. However, most of the fishing effort is south and offshore of the North West Cape, with areas
of medium and high-density fishing activity located to the south of Ningaloo Reef and west of Shark Bay. No vessels were
active in the fishery in 2014‐15 or 2015-16 seasons (Woodhams and Bath 2017).

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7.3.3.4 Western Australian Managed Fisheries

State-based Western Australian commercial fisheries that overlap the ZPI are described in Table 7-13.

Table 7-13: Western Australia fisheries within the ZPI

Fishery Name Distance from Description

Prelude (km)

Mackerel Fishery 0 The Mackerel Managed Fishery targets Spanish mackerel (Scomberomorus commerson) using near-surface trawling gear
from small vessels in coastal areas around reefs, shoals and headlands. Jig fishing is also used to capture grey mackerel
(S. semifasciatus) (Molony et al. 2015).
The commercial fishery extends from Geraldton to the Northern Territory border. There are three managed fishing areas:
Kimberley (Area 1), Pilbara (Area 2), and Gascoyne and West Coast (Area 3). The majority of the catch is taken from
waters off the Kimberley coasts (Lewis and Jones 2017), reflecting the tropical distribution of mackerel species (Molony et
al. 2015). The majority of fishing activity occurs around the coastal reefs of the Dampier Archipelago and Port Hedland
area, with the seasonal appearance of mackerel in shallower coastal waters most likely associated with feeding and gonad
development prior to spawning (Mackie et al. 2003).

West Coast Deep Sea 0 The West Coast Deep Sea Crustacean Managed Fishery extends north from Cape Leeuwin to the WA/NT border in water
Crustacean depths great than 150 m within the Australian Fishing Zone, including the Operational Area. The fishery targets deep water
crustaceans, with the vast majority (>99%) of the catch landed in 2015 comprised of crystal crabs (How and Yerman 2017).
Two vessels operated in the fishery in 2015, using baited pots operated in a longline formation in the shelf edge waters
mostly in depths between 500 and 800 m (How and Yerman 2017). Fishing effort was concentrated between Fremantle
and Carnarvon.

South West Coast 0 The South West Coast Salmon Managed Fishery operates on various beaches south of the metropolitan area and includes
Salmon all Western Australian waters north of Cape Beaufort except Geographe Bay. No fishing takes place north of the Perth
metropolitan area (well beyond the ZPI), despite the managed fishery boundary extending to Cape Beaufort (Western
Australia / Northern Territory border).

Northern Demersal 0 The Northern Demersal Scalefish Managed Fishery operates off the northwest coast of Western Australia in the waters
Scalefish east of 120°E longitude. The permitted means of operation within the fishery include handline, dropline and fish traps; since

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Prelude (km)
2002 it has essentially been a trap-based fishery. Gear restrictions and spatial zones as the primary management
measures. The main species landed by this fishery are red emperor and goldband snapper (Newman et al. 2017b). In
2015, there were 7 vessels with fishing rights (Newman et al. 2017b). The Northern Demersal Scalefish Managed Fishery
overlaps the Operational Area.

Marine Aquarium and 28 The Marine Aquarium and Specimen Shell managed fisheries are largely diver-based, with effort concentrated around the
Specimen Shell Capes region, Perth, Geraldton, Exmouth and Dampier. Effort in these fisheries is relatively low and spread over a large
geographic area. Given the nature of the fisheries, effort is expected to be largely restricted to coastal waters < 30 m water
depth.

Abalone 28 The Western Australian abalone fishery includes all coastal waters from the Western Australian and South Australian
border to the Western Australian and Northern Territory border. The fishery is concentrated on the south coast (greenlip
and brownlip abalone) and the west coast (Roe’s abalone). Abalone are harvested by divers, limiting the fishery to shallow
waters (typically < 30 m). No commercial fishing for abalone north of Moore River (zone 8 of the managed fishery) has
taken place since 2011/2012 (Strain et al. 2017).

Broome Prawn 28 The Broome Prawn Managed Fishery is one of the four northern managed prawn fisheries (the others are the Kimberley,
Nickol Bay and Onslow prawn managed fisheries). It is the least active of these four fisheries, with 0.3 tonnes of western
king prawns and 0.8 tonnes of coral prawns landed in 2015 (Sporer et al. 2017). The extent of the Broome Prawn Managed
Fishery is approximately 28 km from the Operational Area.

Kimberley Prawn 47 The Kimberley Prawn Managed Fishery operates between Koolan Island and Cape Londonderry. Its target catch is banana
prawns (Penaeus merguiensis) but also catches tiger prawns (Penaeus esculentus), endeavour prawns (Metapenaeus
endeavouri) and western king prawns (Penaeus latisulcatus). Landings in 2016 (Sporer et al. 2017) season were 155
tonnes. The catch season is from early April to late November. The extent of the Kimberley Prawn Managed Fishery is
located approximately 47 km from the Operational Area.

Kimberley Gillnet and 213 The limited entry Kimberley Gillnet and Barramundi Fishery operates from the Western Australian/Northern Territory border
Barramundi to the northern end of Eighty Mile Beach in the nearshore and estuarine zones. The managed fishery boundary extends
approximately 3 nm from the shoreline. In 2013, six vessels fished in the Kimberley Gillnet and Barramundi Fishery. The
fishery targets barramundi (Lates calcarifer), blue threadfin (Polydactylus macrochir) and king threadfin (Eleutheronema

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tetradactylum) (Newman et al. 2017a). The extent of the fishery is located approximately 213 km to the east (near to the
shoreline) of the Operational Area.

Pearl Oyster Fishery 0 The Western Australian Pearl Oyster Fishery is the only remaining significant wild-stock fishery for pearl oysters in the
world. Pearl oysters (Pinctada maxima) are collected by divers in shallow coastal waters along the Northwest Shelf and
Kimberley, which are mainly for use in the culture of pearls. The fishery is separated into four management zones; the
Prelude FLNG facility lies within management zone 3, however the Operational Area is much deeper than safe diving depths
in which pearl oyster fishing occurs. Most pearl fishing occurs in inner continental shelf waters (< 30 m) along the Kimberley
and Pilbara coastlines.
Given the fishery is diver-based (i.e. restricted to safe diving depths) interaction with fishery participants from the operation
of the Prelude FLNG facility are very unlikely.

Pilbara Trap 477 The Pilbara Trap Managed Fishery is one of three fisheries (Pilbara Fish Trawl (Interim) Managed Fishery, Pilbara Line
Fishery) that make up the Pilbara Demersal Scalefish Fisheries. The main species that are caught in this subregion are
bluespotted emperor (Anax nigrofasciatus), red emperor (Lutjanus seba) and rankin cod (Epinephelus multinotatus). There
are six licences in the Pilbara Trap Managed Fishery that are operated across three vessels. Fishing in this area is not
restricted by seasons. The extent of the Pilbara Trap Managed Fishery is located approximately 477 km south-west of the
Operational Area.

Pilbara Fish Trawl 560 The Pilbara Fish Trawl (Interim) Managed Fishery is one of three fisheries (Pilbara Trap Managed Fishery and Pilbara Line
Fishery) that make up the Pilbara Demersal Scalefish Fisheries. The main species that are caught in this subregion are
bluespotted emperor (Anax nigrofasciatus), red emperor (Lutjanus seba) and rankin cod (Epinephelus multinotatus). The
fishery is restricted to less than approximately 2% of the North West Shelf. The trawling method uses a single net with
extension sweeps. The extent of the Pilbara Fish Trawl (Interim) Managed Fishery is located approximately 560 km south-
west of the Operational Area.

Nickol Bay Prawn 560 The Nickol Bay Prawn Managed Fishery targets penaeid prawns (primarily banana prawns) using trawl gear. The target
species typically inhabits sandy and muddy substrate in < 45 m water depth. Landings in the fishery in 2015 were
approximately 87 tonnes, comprised largely of banana prawns (Sporer et al. 2017). The annual landing in 2015 was
approximately 87 tonnes. The catch effort from the 2016 season was 17 tonnes. The extent of the Nickol Bay Prawn
Managed Fishery is approximately 560 km from the Operational Area.

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Onslow Prawn 920 The Onslow Prawn Managed Fishery is one of five prawn fisheries that are collectively referred to as the North Coast
Prawn Managed Fisheries. The North Coast Prawn Managed Fisheries produced approximately 200-300 t annually. These
fisheries all use low opening, otter prawn trawl systems. The catch effort from the 2016 season was negligible; only one
boat fished in the Onslow Prawn Managed Fishery area in 2016. The extent of the fishery is located approximately 920 km
south-west of the Operational Area.

Exmouth Gulf Prawn 1,263 The Exmouth Gulf Managed Fishery targets penaeid prawns (primarily banana prawns) using trawl gear within Exmouth
Gulf. The target species typically inhabits sandy and muddy substrate in < 45 m water depth. The fishery is of high value,
with approximately 1,067 tonnes landed in 2015, with the town of Exmouth the main port for participants in the fishery. The
fishery is managed based on input controls, temporal closures and spatial closures (Kangas et al. 2017c).

West Coast Rock 1,272 The West Coast Rock Lobster Fishery targets the western rock lobster (Panulirus cygnus) from Shark Bay south to Cape
Lobster Leeuwin using baited traps (pots). In 2008, it was determined that the allocated shares of the West Coast Rock Lobster
resource would be 95% for the commercial sector, 5% to the recreational sector, and one tonne to customary fishers.
The commercial fishery has been Australia’s most valuable single-species wild capture fishery. In 2010/2011, the fishery
moved to an individually transferable quota fishery. The fishery is managed using zones, seasons and total allowable catch.
Landings in 2015 were 6,416 tonnes (de Lestang and Rossbach 2017).

Gascoyne Demersal 1,470 The Gascoyne Demersal Scalefish Fishery comprises commercial and recreational fishing for demersal scalefish in the
Scalefish continental waters of the Gascoyne Coast Bioregion. The fishery is located between the southern Ningaloo coast to south
of Shark Bay with a closure area from Point Maud to Tantabiddi. Commercial vessels have traditionally targeted the
oceanic stocks of pink snapper (Pagrus auratus) during the winter months (fishing spawning aggregations in peak season
of June to July). The present fishery also targets other demersal species including the goldband snapper (Pristipomoides
spp.), red emperor (Lutjanus sebae), other emperors and cod.

Shark Bay Scallop 1,512 The Shark Bay Scallop Managed Fishery targets saucer scallops (Ylistrum balloti) using otter trawls. The stock is currently
recovering after sustained poor recruitment since 2010 (Kangas et al. 2017a). Annual catches in the fishery are highly
variable due to recruitment. Scallops occur on sandy and muddy sediments, which may also host commercially exploited
prawns; a number of vessels participate in both the Shark Bay Scallop Managed Fishery and the Shark Bay Prawn
Managed Fishery (Kangas et al. 2017a).

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Fishery Name Distance from Description

Prelude (km)

Shark Bay Prawn 1,512 The Shark Bay Prawn Managed Fishery is the highest producing Western Australian fishery for prawns. It targets the
western king prawn (Penaeus latisulcatus) and brown tiger prawn (P. esculentus) and takes a variety of smaller prawn
species including endeavour prawns (Metapenaeus spp.) and coral prawns (various species). Prawns are caught using
otter trawls over sandy or muddy substrates, with over 2,000 tonnes landed in 2015 (Kangas et al. 2017b). A number of
vessels active in the Shark Bay Prawn Managed Fishery also fish in the Shark Bay Scallop Managed Fishery.

Shark Bay Crab 1,670 The blue swimmer crab (Portunus armatus) resource in Shark Bay is harvested commercially by the Shark Bay crab trap,
prawn trawl and scallop trawl fisheries. Commercial fishing for blue swimmer crabs in Shark Bay was voluntarily halted by
industry in April 2012 to facilitate stock rebuilding. The fishery was reopened in 2013/14, with a 450 tonne catch limit
instituted for the 2015 season.

Shark Bay Beach 1,685 The Shark Bay Seine and Mesh Net Managed Fishery operates from Denham and used a combination of beach seine and
Seine and Mesh Net mesh net gears to mainly take four species/groups including whiting (mostly yellowfin with some goldenline), sea mullet
(Mugil cephalus), tailor (Pomatomus saltatrix) and western yellowfin bream (Acanthopagrus morrisoni).
This fishery is managed by limited entry, gear restrictions (e.g. vessel size, net length and mesh size) and permanently
closed waters (e.g. Hamelin Pool, Big Lagoon, Denham foreshore).

West Coast Demersal 1,765 The West Coast Demersal Scalefish Fishery comprises inshore and offshore suites of demersal scalefish species that are
Scalefish exploited by different commercial fisheries, recreational and charter fishers operating in the West Coast Bioregion. The
West Coast Inshore Demersal suite occurs in waters < 250 m deep and is comprised of approximately 100 different
species, the most important of which are West Australian dhufish (Glaucosoma hebraicum) and pink snapper (Pagrus
auratus). Less important species include redthroat emperor (Lethrinus miniatus), bight redfish (Centroberyx gerrardi) and
baldchin groper (Choerodon rubescens).
The West Coast Offshore Demersal suite occurs in waters < 250 m deep and includes eightbar groper (Hyporthodus
octofasciatus), hapuka (Polyprion oxygeneios), blue-eye trevalla (Hyperoglyphe antactica) and ruby snapper (Etelis
carbunculus).
Access to the fishery is limited. Gear and other restrictions apply in the form of maximum number of lines and hooks and
arrangements regulating the carriage of lines and fish.

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7.3.3.5 Northern Territory Managed Fisheries

Northern Territory-based commercial fisheries that overlap the ZPI are described in Table 7-14.

Table 7-14: Northern Territory fisheries within the ZPI

Fishery Name Distance from Description

Prelude (km)

Aquarium Fishery 537 The Northern Territory Aquarium Fishery targets a range of marine, estuarine and freshwater species for the aquarium
trade, including finfish (e.g. freshwater rainbowfish), invertebrates (e.g. hermit crabs) and plants. Fishing is typically either
from boat or shore by diving, nets and hand collection. These methods restrict fishing activity in shallow coastal, estuarine
and riverine waters. There are approximately 11 licences and three boats active in the fishery each year.
The managed fishery area extends to the edge of the Australian fishing zone (200 NM from the coast) and is partially
overlapped by the ZPI. Given activity in the fishery is restricted to coastal waters, the operation of the Prelude FLNG facility
is unlikely to impact upon the fishery.

Offshore Net and Line 537 The Offshore Net and Line Fishery covers an area of over 522,000 km2 and extends from the NT high water mark to the
Fishery boundary of the Australian fishing zone (NT Government 2017). The fishery permits both pelagic gillnets and longline gear
and targets Australian and common blacktip sharks, spottail sharks and grey mackerel; however, longlines have not been
used since 2013 due to a drop in shark fin price (NT Government 2017). The majority of the fishing effort is in the coastal
zone (within 12 NM of the coast) and immediately offshore in the Gulf of Carpentaria (NT Government 2017). Effort beyond
12 NM from shore is typically very low
The number of licences for the fishery is restricted to 17 and generally 11 licences are active in any given year (NT
Government 2017).

Spanish Mackerel 537 The fishery extends from the NT high water mark to the outer limit of the Australian fishing zone (NT Government 2017).
Fishery The fishery employs troll lines, floating handlines and rods. The majority of the fishing effort occurs in the vicinity of reefs,
headlands and shoals and includes waters near Bathurst Island, New Year Island, the Wessel Islands around to Groote
Eylandt and the Sir Edward Pellew Group of islands (NT Government 2017). The target species of the fishery is the narrow-
barred Spanish mackerel, however a small number of other mackerels are also taken.

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Fishery Name Distance from Description

Prelude (km)

Demersal Fishery 540 The Demersal Fishery boundary extends from 15 nautical miles from the NT coastal waters mark to the outer limit of the
Australian fishing zone, excluding the area of the Timor Reef Fishery. The fishery employs trawl, hand and drop lines, and
trap fishing methods. The main target species of the fishery are red snappers, goldband snappers, saddletail, and crimson
snapper. There are currently 18 licences issued for the fishery (NT Government 2017).

Timor Reef Fishery 569 The Timor Reef Fishery operates in remote offshore waters in the Timor Sea in a defined area approximately 370 km north-
west of Darwin. The fishery extends north-west of Darwin to the WA-NT border and to the outer limit of the AFZ and covers
an area of ~28,811 km2 (NT Government 2017). The target species is goldband snapper, with other tropical snappers such
as crimson snapper and saddletail snapper also consisting part of the catch. The majority of the fishing effort is undertaken
using drop-lines and occurs primarily in the 100 – 200 m depth range.

Pearl Oyster Fishery 537 The Northern Territory pearl oyster fishery is currently a small diver-based fishery collecting pearl shell for mother-of-pearl.
Most pearl oysters used in aquaculture in the Northern Territory are reared from hatchery stock, which are grown at farms
locations are in waters around Darwin and East Arnhem Land (beyond the ZPI). Fishing for pearl oysters is diver-based,
with five licences currently issued to fishers. The managed fishery area extends from the Australian coastline to the edge of
the Australian fishing zone. As the fishery is diver-based, fishing activity is likely to be restricted to occupational diving
depths (< 30 m). Hence, fishing activity may only occur in a very limited part of the managed fishery area. Given activity in
the fishery is restricted to coastal waters, the operation of the Prelude FLNG facility is unlikely to impact upon the fishery.

Coastal Line Fishery 618 The Coastal Line fishery extends 15 nautical miles from the low water mark around the entire NT coastline. The fishery is
divided into two zones, which divide the coastline at Vashon Head on the Cobourg Peninsula (NT Government 2017). The
majority of fishing effort is focused around rocky reefs within 150 km of Darwin where Black Jewfish are targeted using
mainly hook and line gear (NT Government 2017). Fish traps and droplines are also permitted beyond 2 NM from the
coastline in the Eastern Zone of the fishery, and gillnets with a maximum drop of 5 m are also permitted (NT Government
2017). Catch from droplines and traps account for less than 7% of the total reported catch (NT Government 2017).

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7.3.3.6 Aquaculture
There are no aquaculture operations within the Operational Area; aquaculture is
typically restricted to shallow coastal waters. Aquaculture in the region consists
primarily of culturing hatchery reared and wild caught oysters (Pinctada maxima) for
pearl production, which is primary centred around Broome and the Dampier Peninsula.
Leases typically occur in shallow coastal waters at depths of less than 20 m (Fletcher
et al. 2006).

7.3.4 Tourism and Recreation

No tourism activities are known to occur within the Operational Area, but tourism
activities occur widely in the ZPI. Most tourism in the ZPI is nature-based and hence is
typically associated with outstanding natural features such as the Kimberley coastline
and the offshore reefs and islands (e.g. Rowley Shoals). The remoteness of the region
results in most offshore tourism activities being conducted from organised expeditions
based on larger vessels.
Tourism makes a significant contribution to the regional economy, with the town of
Broome (beyond the ZPI) providing a central node for many tourism-related activities in
the region.

7.3.5 Defence
There are no defence exercise areas within the Operational Area or the ZPI, but
defence activities may occur within the ZPI.

7.3.6 Shipping
Shipping activity in the vicinity of the Operational Area is considered high. However,
almost all vessel activities in the Operational Area are associated with the operation of
the Prelude FLNG facility and Ichthys facilities (e.g. offtake tankers, support vessels
etc.).

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Figure 7-12: Shipping levels within the operational area and broader ZPI

7.3.7 Indonesian Coastline

The Indonesian is located over 300 km north of the Operational Area at the closest
point, near the limits of the ZPI.
Indonesia is the world’s largest archipelagic state and Indonesian waters play an
important role in the global water mass transport system (Asian Development Bank
ADB] et al. 2014). Indonesia has some of the most biologically rich coral reefs in the
world with over 590 coral species having been identified. Coastal reefs are a primary
source of food and income for coastal communities, as well as forming an integral part
of the countries tourism industry (ADB et al. 2014). Coastal areas also support
aquaculture production of algae, finfish and crustaceans. In addition to coral reefs,
coastal habitats include sandy beaches, rocky shorelines, seagrass meadows, and
mangroves.

7.3.8 Oil and Gas Industry

Oil exploration activities in the Timor Sea commenced in the late 1960s. Since this time
numerous wells have been drilled throughout the region. Petroleum exploration has
been active in the Browse Basin since the 1980s, with several commercial discoveries
since that time. It is expected that petroleum exploration and development activities will
continue in the region into the future.
There are several operating petroleum production facilities in the vicinity of the Prelude
FLNG facility. The Ichthys facilities are the closest, situated approximately 20 km south
of the Operational Area. The Montara facility is located approximately 188 km north-
east of the Operational Area.

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8.0 Acceptable Levels of Impact and Risk for the Petroleum

Activities
The OPGGS (E) Regulations require the titleholder include an evaluation of all the
impacts and risks that determined whether these will be of an ‘acceptable’ or
‘unacceptable’ level. To this end, Shell has determined acceptable levels of impact to
the environmental receptors that may credibly be impacted by the petroleum activities
considered within this EP. The process by which Shell has determined the acceptability
of risks and impacts is detailed below.

8.1 Considerations in Developing Defined Acceptable Levels of Impact and

Risk
Shell has established defined acceptable levels of impacts and risks for the petroleum
activities considered in this EP relating to all the environmental receptors that were
identified as being credibly impacted, or at risk of being impacted. The outcomes of the
evaluation of environmental impacts and risks were assessed against these defined
acceptable levels to determine if the impacts or risks were acceptable.
The following were considered when establishing the acceptable levels of impacts and
risks:
• The principles of ESD
• Other requirements applicable to the Prelude project (e.g. laws, policies, standards,
conventions etc.)
• Significant impacts 6 to MNES
• Internal context and
• External context.

Each of these considerations are elaborated on below.

8.1.1 Principles of Ecologically Sustainable Development

Shell has considered the principles of ESD in defining acceptable levels of impacts and
risks, as defined in Section 3A of the EPBC Act 1999. The principles of ESD are
summarised as:
• Decision-making processes should effectively integrate both long-term and short-term
economic, environmental, social and equitable considerations.
• If there are threats of serious or irreversible environmental damage, lack of full scientific
certainty should not be used as a reason for postponing measures to prevent
environmental degradation.

6 Significant impacts refer specifically to the levels of impacts defined in the Matters of National
Environmental Significance - Significant impact guidelines 1.1. Any subsequent reference in this EP to
significant impacts refers to these levels unless stated otherwise.

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• The principles of inter-generational equity – that the present generation should ensure
that the health, diversity and productivity of the environment is maintained or enhanced
for the benefit of future generations.
• The conservation of biological diversity and ecological integrity should be a fundamental
consideration in decision-making.
• Improved valuation, pricing and incentive mechanisms should be promoted.

8.1.2 Other Relevant Requirements

Shell considered other relevant requirements that apply to the environmental
management of the petroleum activities considered in this EP, including legislation,
policies, standards and guidelines in establishing acceptable levels of impacts and
risks (Refer to Section 3.0).

8.1.3 Significant Impacts to MNES

Given this EP forms the basis for NOPSEMA’s assessment of matters protected under
Part 3 of the EPBC Act in Commonwealth waters, Shell has given specific attention to
the acceptability of impacts and risks to MNES. Where a potential interaction between
the relevant MNES and an aspect of the petroleum activities covered by this EP was
identified, the criteria provided are listed in Table 8-1.
Potential impacts and risks to MNES from aspects of the petroleum activities were
deemed inherently acceptable if:
• The significant impact criteria in relation to the MNES are not anticipated to be
exceeded
• The management of the aspect is aligned with published guidance material from the
DAWE, including threat abatement plans, recovery plans and conservation advice.
Additionally, the Prelude FLNG project was assessed under the EPBC Act as an
Environmental Impact Statement; and a series of conditions were applied to the project
as a result of this assessment. These conditions are summarised in Table 3-2 which
includes cross-references to the relevant sections within the EP and supporting
documentation demonstrating how the requirements have been met.

Table 8-1: MNES Significant impact criteria applied to the petroleum activities considered
in this EP

Category Significant Impact Criteria

Listed Critically An action is likely to have a significant impact on critically endangered or
Endangered and endangered species if there is likelihood that it will:
Endangered
• Lead to a long-term decrease in the size of a population
species
• Reduce the area of occupancy of the species
• Fragment an existing population
• Adversely affect habitat critical to the survival of a species
• Disrupt the breeding cycle of a population
• Modify, destroy, remove, isolate or decrease the availability or quality
of habitat to the extent that the species is likely to decline
• Result in invasive species that are harmful to a critically endangered or
endangered species becoming established in the endangered or
critically endangered species' habitat
• Introduce disease that may cause the species to decline, or
• interfere with the recovery of the species.

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Category Significant Impact Criteria

Listed An action is likely to have a significant impact on vulnerable species if there is a
Vulnerable likelihood that it will:
Species
• Lead to a long-term decrease in the size of an important population
• Reduce the area of occupancy of and important population
• Fragment an existing important population into two or more populations
• Adversely affect habitat critical to the survival of a species
• Disrupt the breeding cycle of a population
• Modify, destroy, remove, isolate or decrease the availability or quality
of habitat to the extent that the species is likely to decline
• Result in invasive species that are harmful to a vulnerable species
becoming established in the vulnerable species' habitat
• Introduce disease that may cause the species to decline, or
• Interfere substantially with the recovery of the species.
Listed Migratory An action is likely to have a significant impact on migratory species if there is
Species likelihood that it will:
• Substantially modify, destroy or isolate an area of important habitat for
a migratory species
• Result in an invasive species that is harmful to the migratory species
becoming established in an area of important habitat for the migratory
species, or
• Seriously disrupt the lifecycle of an ecologically significant proportion of
the population of a migratory species.
Wetlands of An action is likely to have a significant impact on a wetland of international
International importance if there is likelihood that it will result in:
Importance
• Areas of wetland being destroyed or substantially modified
• A substantial and measurable change in the hydrological regime of the
wetland
• The habitat or lifecycle of native species dependent upon the wetland
being seriously affected
• A substantial and measurable change in the water quality of the
wetland which may adversely impact on the biodiversity, ecological
integrity, social amenity or human health, or
• An invasive species that is harmful to the ecological character of the
wetland being established in the wetland.
Commonwealth An action is likely to have a significant impact on the environment in a
Marine Area Commonwealth Marine Area if there is likelihood that it will:
• Result in a known or potential pest species becoming established in
the Commonwealth marine area
• Modify, destroy, fragment, isolate or disturb an important or substantial
area of habitat such that an adverse impact on marine ecosystem
functioning or integrity on a Commonwealth marine area results
• Have a substantial adverse effect on a population of a marine species
or cetacean including its life cycle and spatial distribution
• Result in a substantial change in air quality or water quality which may
adversely impact on biodiversity, ecological integrity 7, social amenity or
human health

7
In the context of the Prelude FLNG, a change to ecological integrity is considered to take into account broadscale, long
term impacts to the ecosystem. With regards to the Commonwealth marine environment, the operational area is located
in open offshore waters and the seabed is generally characterised by soft sediments. These characteristics are typical
of the offshore Browse Basin.”

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Category Significant Impact Criteria

• Result in persistent organic chemicals, heavy metals, or other
potentially harmful chemicals accumulating in the marine environment
such that biodiversity, ecological integrity2, social amenity or human
health may be adversely affected, or
• Have a substantial adverse impact on heritage values of the
Commonwealth marine area, including damage or destruction of an
historic shipwreck.

8.1.4 Internal Context

Shell considered its internal requirements when establishing acceptable levels of
impacts and risks. This context included Shell’s environment policy, environmental risk
management framework, internal standards, procedures, technical guidance material
and opinions of internal stakeholders.
The following outlines Shell’s internal impact and risk assessment defined acceptable
levels:
• Residual planned impacts that are ranked as minor or less (i.e. minor, slight, no effect or
positive effect) and residual risks for unplanned events ranked light or dark blue, are
inherently 'acceptable', if they meet legislative and Shell requirements and the
established acceptable levels of impacts and risks.
• Moderate residual impacts, and yellow and red residual risks, are ‘acceptable’ with
appropriate controls in place and if good industry practice can be demonstrated.
• Major and massive residual impacts from planned activities, and massive residual risks
from unplanned activities, are ‘unacceptable’. The activity (or element of) should not be
undertaken as the impact or risk is serious and does not meet the principles of ESD,
legal requirements, Shell requirements or regulator and stakeholder expectations. The
activity requires further assessment to reduce the risk to an acceptable level.
Table 8-2 provides a summary of the acceptability statements, as correlated to the
rankings presented in the environmental impact and risk assessments in Section 9.0

Table 8-2: Acceptability Categories

Acceptability Statement Residual Impact (Planned) Residual Risk

(Unplanned)
Inherently acceptable - Manage for • Light Blue
• Positive Impact Consequence
continuous improvement through • Dark Blue
• No Impact Consequence
effective implementation of the • Slight Impact Consequence
HSSE and SP management system
• Minor Impact Consequence
Acceptable with controls - Apply the • Yellow
• Moderate Impact Consequence
hierarchy of control to reduce the • Red
risks to ALARP
Unacceptable • Major Impact Consequence • Red - X
• Massive Impact Consequence

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8.1.5 External Content

Shell also considered the external context when establishing acceptable levels of
impacts and risks. This includes information provided by stakeholders during the
preparation of the EP and the Prelude FLNG EIS. Shell routinely implements an
ongoing stakeholder engagement program managed by Shell’s EGR team. Reference
is made to Section 5.0 for further information on the stakeholder engagement process
and a summary of responses and objections/claims made by Relevant Persons is
included in Table 5-3 and Table 5-4 which have informed the defined acceptable levels
of impact.

8.1.6 Defined Acceptable Levels of Impact and Risk

The acceptable levels of impacts and risks to environmental receptors from the
petroleum activities considered in this EP are summarised in Table 8-3.

Table 8-3: Summary of acceptable levels of impact for environmental receptors that may
be affected by the petroleum activities considered in this EP

Receptor Receptor Sub- Acceptable Level Justification

Category category of Impact
Physical Water quality Limited As the larger impact footprint compared to
Environment environmental support vessels there are routine planned liquid
impact to water discharges from the facility. This may result in
quality and quality is localised water quality impacts in the immediate
maintained so that vicinity. Modelling studies indicate the impacts
biodiversity, will be localised around the facility which is
ecological integrity, characterised as open offshore waters; typical of
social amenity and and well represented within the Browse Basin.
human health Liquid discharges from the FLNG cannot be
values are avoided. However, the area influenced from
protected. routine operational discharges is expected to be
limited to within 1 km of the liquid discharge
locations. The potential magnitude of impacts to
marine ecosystems is slight. Given the offshore
location and absence of particularly sensitive
marine ecosystems at the FLNG location and
immediate surrounds, potential impacts within
1 km of the FLNG are considered acceptable.
Sediment quality Limited The liquid discharges from the facility (e.g.
environmental PFW, drainage water) may increase the
impact to sediment concentration of potential contaminants within
quality and quality is sediments around Prelude following settlement,
maintained so that precipitation and/or adsorption to particulates.
biodiversity, This slight elevation in contaminant levels above
ecological integrity, background concentrations is anticipated to
social amenity and occur over decades as described further in
human health Section 9.9. Sediment quality in the vicinity of
values are the FLNG and Operational Area is characteristic
protected. of the conditions of the offshore region and well
represented within the Browse Basin.
Impacts to sediment quality from the project
cannot be completely avoided. However, the
area influenced is expected to be limited to
within 1 km of sources of potential sediment
contamination (e.g., a result of discharges from
the FLNG). The potential magnitude of impacts
to marine ecosystems is slight. These impacts
are considered to be acceptable when

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Receptor Receptor Sub- Acceptable Level Justification

Category category of Impact
considering the seabed is smooth and bare of
hard substrates, with predominantly sandy
sediments observed.
Air quality Limited The Operational Area is located in the open
environmental ocean and is far-removed from the nearest
impact to air quality. residential or sensitive populations of the WA
Defined as no coast, with limited interaction with regional
substantial change airsheds. It should be noted that risks and
in air quality which impacts to the workforce associated with this
may adversely petroleum activity are addressed in the
impact on corresponding Safety Case and are not
biodiversity, addressed in this EP.
ecological integrity The MNES Significant Impact Guidelines 1.1
social amenity or under the EPBC Act 1999 (DoE 2013) define
human health. significant impact to air quality as ‘substantial
No significant change in air quality which may adversely
impacts to air impact on biodiversity, ecological integrity;
quality during the social amenity or human health’. There is no
project. definition of the term ‘substantial’ however the
above definition highlights that the main
concerns are impacts on biodiversity, ecological
integrity, social amenity or human health.
Due to the lack of background air quality, the
National Environment Protection Measures
(NEPM) Air Quality and Air Toxics guidelines
will be used to judge acceptability of impact on
air quality. This is deemed acceptable as the air
quality criteria are already conservatively set to
afford protection for the health of the general
population including its most vulnerable groups
such as children and the elderly.
Biological Benthic Limited Benthic habitats and communities within the
Environment communities environmental Operational Area are widely represented in the
impact which Browse Basin, with millions of hectares of
directly impacts similar broad-scale soft benthic habitats
bare sediment occurring in the region and they are not
benthic habitats considered of high environmental value. Given
outside of the there are no named banks, shoals, reefs or
Operational Area as islands located within the Operational Area,
a result of the direct disturbance to benthic habitats contained
petroleum activities within the Operational Area are deemed
which adversely acceptable.
effects biological Sensitive benthic receptors (corals, macroalgae,
diversity or seagrasses and mangroves) associated with
ecological integrity. shoals, banks, reefs and islands of the Browse
Limited Basin and Timor Sea, are considered of high
environmental environmental value. Shell considers direct
impacts to high- impacts to these receptors as unacceptable.
value sensitive Given the separation distance from the FLNG,
benthic these receptors would only be impacted by a
communities large-scale hydrocarbon spill, such as a well
(corals, blowout. Shell considers any large-scale
macroalgae, hydrocarbon spill to be unacceptable.
seagrasses and
mangroves)
associated with
named reefs, banks
and shoals.

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Receptor Receptor Sub- Acceptable Level Justification

Category category of Impact

Pelagic Limited The waters surrounding the facility are

communities environmental characterised as open offshore waters, typical of
(Non-Threatened impact leading to the offshore Browse Basin. Resident and
or Migratory) adverse effect on transient pelagic species and associated habitat
pelagic within the Operational Area are not specifically
communities, protected or unique and are not considered of
populations, high environmental value. Species are
habitats or spatial regionally well represented and considered
distribution of a typical of the Browse Basin and Timor Sea.
species.
Key Ecological Limited impact to KEFs in the Browse Basin are largely
Features (KEFs) environmental geomorphic features that provide important
values of KEFs ecosystem services primarily as a result of their
unique physical features (e.g. provision of hard
substrates, facilitation of upwelling etc.). These
are geographically diverse features that cover a
large extent.
Given there are no planned impacts to KEFs
from the Prelude project, any impacts to KEFs
will be below the significant impact threshold.
Shell considers any impacts to KEFs to be
unacceptable.
Threatened No significant Threatened ecological communities – Refer to
Species and impacts to listed Section 7.2.4.
Ecological Threatened The waters surrounding the FLNG facility are
Communities (Endangered and characterised as open offshore waters, typical of
Vulnerable) or the offshore Browse Basin. Resident and
Migratory MNES transient species and associated habitat within
fauna populations. the Operational Area are not specifically
Management of protected or unique and are not considered of
aspects of the high environmental value. Species are
project must be regionally well represented and considered
aligned to typically of the Browse Basin and Timor Sea.
conservation
advice, recovery
plans and threat
abatement plans,
including for bird
and marine turtle
species.

Ramsar Limited Ramsar wetlands would only be impacted by a

Wetlands environmental large-scale hydrocarbon spill., such as a well
impacts to blowout. In a regional environmental context,
ecological values of the nearest Ramsar wetland is 169 km away
Ramsar wetlands (Ashmore Reef). Shell considers any large-scale
hydrocarbon spill to be unacceptable.
Threatened and Limited Shell considers significant impacts to MNES to
Migratory environmental be unacceptable. Impacts that are below the
Species impacts to listed significant impact threshold defined in Table 8-1
Threatened are considered as acceptable.
(Endangered and
Vulnerable) or
Migratory MNES
fauna populations
(Refer to Table 8-1).

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Receptor Receptor Sub- Acceptable Level Justification

Category category of Impact
Commonwealth Limited Shell considers significant impacts to MNES to
Marine Area environmental be unacceptable. Impacts that are below the
impacts to the significant impact threshold defined in Table 8-1
Commonwealth are considered as acceptable.
Marine Area (Refer
to Table 8-1).
WA Mainland Limited The WA mainland coastline would only be
Coastline environmental impacted by a large-scale hydrocarbon spill,
impacts to mainland such as a well blowout. Shell considers any
coastline. large-scale hydrocarbon spill to be
unacceptable.
Socio- Heritage Limited Listed heritage values would only be impacted
economic and environmental by a large-scale hydrocarbon spill, such as a
Cultural impacts to defined well blowout. In a regional environmental
Environment heritage values context, the nearest heritage place is 155 km
away and the nearest named shipwreck is
18 km away (Refer to Section 7.3.1). Shell
considers any large-scale hydrocarbon spill to
be unacceptable.
Marine Protected Limited Marine Protected Areas would only be impacted
Areas environmental by a large-scale hydrocarbon spill, such as a
impacts to well blowout. In a regional environmental
ecological values of context, the nearest marine protected area is
Marine Protected the Commonwealth Kimberley AMP
Areas (approximately 111 km from the FLNG). Shell
considers any large-scale hydrocarbon spill to
be unacceptable.
Fishing Industry No interference with Impacts or restricted access to targeted fish
fishing to a greater stocks may measurably reduce the potential
extent than is revenue for commercial fishers, charter
necessary for the operators or other benefits provided to
exercise of right traditional fishers. Shell considers this to be
conferred by the unacceptable.
titles granted to In a regional context, commercial, recreational
carry out petroleum and traditional fishing is typically concentrated
activities. mostly in coastal/shallow waters and minimum
fishing effort is known to occur within the vicinity
of the Operational Area, given its remoteness
offshore.
Shell considers the displacement of other users
(e.g. commercial, recreational and traditional
fishers) from relatively small areas of the open
ocean environment in the Operational Area to
be acceptable and necessary from a safety and
security perspective.

Tourism and No negative Impacts to nature-based tourism resources may

Recreation impacts to nature- deprive the tourism industry of revenue. Shell
based tourism considers this to be unacceptable. In a regional
resources resulting context, there are no known tourist attractions or
in demonstrated destinations within the Operational Area or
loss of income. nearby surrounds, however charter vessels may
transit the broader regional waters.
Shell considers the displacement of other users
(e.g. tourism operators) from the Operational
Area, which is a relatively small area of the open
ocean environment where existing tourism and
recreation use is very low, to be acceptable and

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Receptor Receptor Sub- Acceptable Level Justification

Category category of Impact
necessary from a safety and security
perspective.

Defence No interference with Shell considers the displacement of other users

defence activities as (e.g. defence vessels and aircraft) from
directed by the relatively small areas of the open ocean
Department of environment in the Operational Area to be
Defence. acceptable and necessary from a safety and
security perspective.
In a regional context, there are no designated
military/defence exercise areas in the facility
area and surrounds, however there are regional
defence exercise areas with large geographic
extents.

Shipping No interference with Shell considers the displacement of other users

navigation to a (e.g. commercial shipping) from relatively small
greater extent than areas of the open ocean environment in the
is necessary for the Operational Area to be acceptable and
exercise of right necessary from a safety and security
conferred by the perspective.
titles granted to In a regional context, the major shipping routes
carry out petroleum traversing the Operational Area are associated
activities. with the Prelude FLNG and Ichthys facilities.

Oil and Gas No interference with Shell considers the displacement of other users
Industry other titleholders to (e.g. petroleum exploration and operations) from
a greater extent relatively small areas of the open ocean
than is necessary environment in the Operational Area to be
for the exercise of acceptable and necessary from a safety and
right conferred by security perspective.
the titles granted to In a regional context, the nearest facility/field to
carry out the the Prelude FLNG is the Ichthys development
petroleum activities which lies approximately 17 km south of the
Operational Area.

Indonesian and No impacts to The Indonesian and Timor-Leste coastlines

Timor-Leste Indonesian or could only be impacted by a large-scale
Coastlines Timor-Leste hydrocarbon spill., such as a well blowout. Shell
coastlines or considers any large-scale hydrocarbon spill to
nearshore be unacceptable.
environments are
acceptable.

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9.0 Evaluation of Environmental Impacts and Risks

9.1 Introduction
This section documents the process that identifies and evaluates potential
environmental impacts and risks and develops means of mitigating the effects of
planned activities and the likelihood of unplanned activities of the petroleum activity on
the environment, including socio-economic and cultural impacts. It describes the
approach undertaken to evaluate the magnitude and severity of impact to
environmental and social receptors from activities associated with the petroleum
activities. The resulting proposed management controls form the basis of the
Implementation Strategy (refer Section 10.0) which will be implemented during the
petroleum activity.

9.1.1 Shell Company Approach to Risk Management

At a corporate level, Shell has a standardised Hazards and Effects Management
Process (HEMP), as the process by which Shell identifies and assesses hazards and
implements measures to manage them. This process is consistent with the principles
outlined in the Australian Standard AS/NZS ISO 31000:2009 Risk Management and
Handbook 203:2006 Environmental Risk Management (Figure 9-1). HEMP is a
fundamental element of the Shell Group HSSE and SP Control Framework and is a
process that is applied at every phase of projects and operations.

Figure 9-1: Risk Management Framework (AS/NZS 4360:2004 Risk Management

Shell’s HSSE and SP Management System is a system that is continually improving

due to incorporation of legislative requirements, changing community expectations,
improved available technology, ongoing stakeholder engagement, learning from
incidents industry wide and within Shell, and regular management review. Assurance

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that the HSSE and SP Management System is working, continually improving and that
each Shell company is correctly applying new Shell standards occurs via local self-
assurance and the Shell Global auditing process, which is ongoing and serves to
identify gaps and drive gap closure.
Company standards are at least equal to, but in many cases, more stringent than local
legislation, and aligned with global good industry practice benchmarks such as those
published by the IFC and World Bank. Both legislation and company standards are
continually being updated and requiring a higher level of performance over time.
Concurrently, new technologies are becoming available and making improved
performance possible and more affordable. This continual improvement is reflected in
more challenging ALARP and acceptability benchmarks, leading to better
environmental outcomes over time.
The OPGGS (E) Regulations 13(5)(b) requires that the EP includes ‘an evaluation of all
the impacts and risks, appropriate to the nature and scale of each impact or risk’. This
is further clarified by Reg. 13(6) which states that: ‘To avoid doubt, the evaluation
mentioned in paragraph (5)(b) must evaluate all environmental impacts and risks
arising directly or indirectly from (a) all operations of the activity; and (b) potential
emergency conditions, whether resulting from accident or any other reason.’ Based on
this, Shell has chosen to present ALARP demonstrations for all identified impacts and
risks, regardless of their ranking.
The succeeding sections detail the environmental impacts and risks of operations
associated with the Prelude FLNG petroleum activities on the local and wider
environment, including socio-economic considerations. Activities are described in terms
of magnitude/sensitivity and ranking of planned impacts and unplanned risks. A
description of management actions proposed to reduce any effect on the environment
to ALARP is also presented.
In preparation of this EP, from June through September 2019, a detailed desktop
review of the impact and risks assessments were carried out by various environment
professionals (Prelude Environment Lead, Shell Australia Environment Lead for
Approvals and GHG, and environmental consultants). The review included the
alignment with previous environmental MoCs for the in-force EP, followed by a detailed
desktop assessment, and subsequent peer review of others work to ensure
consistency was applied across the impact and risk assessment review. Throughout
the desktop assessment additional supporting information such as current forecasts
from Shell’s business planning processes were also used to provide input to the impact
assessment.

9.2 Impact Assessment Methodology

This section describes the approach adopted for identifying and assessing impacts on
the environment as relevant to the petroleum activities. Planned activities give rise to
environmental impacts, while unplanned and accidental events pose a risk of
environmental impact, if they occur. The risk ranking of environmental impacts resulting
from unplanned or accidental events is evaluated by identifying the worst-case credible
consequence (without controls) and then assessing the likelihood for the event
occurring (with confirmed controls in place).
The approach aligns with Shell’s methodology that enables a balanced assessment of
planned impacts and unplanned risks, noting that there are some difficulties in relying
solely on the corporate Shell Risk Assessment Matrix (RAM) for assessment of
planned environmental impacts. Therefore, an adapted methodology has been

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developed by Shell (United Kingdom), for use across Shell Group companies, that ties
together both potential ‘Magnitude’ of a predicted impact and the ‘Receptor Sensitivity’
as shown in a summary impact ranking matrix (see Section 9.2.2). The matrix is used
for the assessment of impacts consequences for both planned and unplanned events.
However, for the assessment of unplanned events, the additional likelihood of
occurrence of an event is considered to determine the risk ranking (See Section 9.2.3).
For the purpose of this assessment, key terminology is defined in Table 9-1.

Table 9-1: Definition of Key Terminology for Impact Assessment

Term Definition
Acceptable The level of impact and risk to the environment that may be considered broadly
acceptable regarding all relevant considerations.
Activity Components or elements of work associated with the project. All activities associated
with the project have been considered at a broad level (as outlined in Section 6).
ALARP The point at which the cost (in time, money and effort) of further Risk or Impact
reduction is grossly disproportionate to the Risk or Impact reduction achieved
Aspect Elements of the proponent’s activities or products or services that can interact with
the environment. These include planned and unplanned (including those associated
with emergency conditions) activities.
Control A measure which prevents and/or mitigates risk by reducing the overall likelihood of a
worst-case credible consequence occurring. Controls include existing controls (i.e.
Company management controls or industry standards) or additional controls (i.e.
additional measures identified during the risk assessment processes).
Event An occurrence of a particular set of circumstances. An event can be one or more
occurrences and can have several initiating causes.
Factor Relevant physical, biological, socio‐economic and cultural features of the
environment. These are also referred to as values, sensitivities and/or receptors.
Hazard A substance, situation, process or activity that has the ability to cause harm to the
environment.
Impact Any change to the environment from a planned activity, whether adverse or
beneficial, wholly or partially resulting from a proponent’s environmental aspects.
Impact The outcome of a planned or unplanned event, which can lead to a range of worst
Consequence case, credible consequences. A consequence can be certain or uncertain and can
have positive or negative effects. Consequences can be expressed qualitatively or
quantitatively.
Inherent risk The potential exposure defined as the plausible worst-case event in the absence of
controls
Likelihood Description of probability or frequency of a consequence occurring with controls in
place.
Residual risk The level of risk remaining after risk treatment, i.e. application of controls (inclusive of
unidentified risk).
Residual The level of impact remaining after impact treatment, i.e. application of controls
Impact (inclusive of unidentified impact).

9.2.1 Aspects and Impact/Risk Identification

The initial identification of aspects and potentially associated impacts/risks is carried
out prior to any detailed assessment of the relative importance of each issue, the

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sensitivity of the existing environmental and/or socio-economic values, or the

magnitude of the potential impact, and does not consider potential control measures.
The key aspects arising from the Prelude petroleum activities have been identified as:
• Physical presence
• Lighting
• Underwater noise
• Seabed disturbance
• Vessel movements (unplanned)
• Liquid discharges
• Atmospheric emissions
• Greenhouse gas emissions
• Waste (unplanned)
• IMS (unplanned)
• Loss of containment (including unplanned spills).

9.2.2 Evaluation of Impacts

Impact Consequence Assessment
The ranking of environmental impact consequence is assessed in terms of:
• magnitude based on the size, extent and duration/frequency of the impact; and
• the sensitivity of the receiving receptors.
These are described further below.
Magnitude
Levels of magnitude of environmental impacts are outlined in Table 9-2. The magnitude
of an impact or predicted change takes into account the following (shown descriptively
in Figure 9-2):
• nature of the impact and its reversibility
• duration and frequency of an impact
• extent of the change
• potential for cumulative impacts.

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Figure 9-2: Definition of Magnitude in the Context of Impact Identification and

Classification

The impact magnitude is defined differently according to the type of impact. For readily
quantifiable impacts, such as noise or liquid discharge plume extent, numerical values
can be used while for other topics (e.g. communities and habitats) a more qualitative
definition is applicable. These criteria capture high level definitions, adapted as
appropriate to the offshore context of the Prelude project.

Table 9-2: Magnitude Criteria

+1 • Net positive effect arising from a proposed aspect of the petroleum activity

0 • No environmental damage or effects

-1 • Slight environmental damage contained within the Operational Area

• Effects unlikely to be discernible or measurable
• No contribution to trans-boundary or cumulative effects
• Short-term or localised decrease in the availability or quality of a resource,
not effecting usage

-2 • Minor environmental damage, no lasting effects or persistent effects are

highly localised
• Minor change in habitats or species
• Unlikely to contribute to trans-boundary or cumulative effects
• Short-term or localised decrease in the availability or quality of a resource,
likely to be noticed by users

-3 • Moderate environmental damage that will persist or require cleaning up

• Widespread change in habitats or species beyond natural variability
• Observed off-site effects or damage, e.g. fish kill or damaged habitats
• Decrease in the short-term (1–2 years) availability or quality of a resource
affecting usage
• Local or regional stakeholders’ concerns leading to complaints

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• Minor trans-boundary and cumulative effects

-4 • Severe environmental damage that will require extensive measures to

restore beneficial uses of the environment
• Widespread degradation to the quality or availability of habitats and/or
wildlife requiring significant long-term restoration effort
• Major oil spill over a wide area leading to campaigns and major
stakeholders’ concerns
• Trans-boundary effects or major contribution to cumulative effects
• Mid-term (2–5 year) decrease in the availability or quality of a resource
affecting usage
• National stakeholders’ concern leading to campaigns affecting Company’s
reputation

-5 • Persistent severe environmental damage that will lead to loss of use or loss
of natural resources over a wide area
• Widespread long-term degradation to the quality or availability of habitats
that cannot be readily rectified
• Major impact on the conservation objectives of internationally/nationally
protected sites
• Major trans-boundary or cumulative effects
• Long-term (> 5 year) decrease in the availability or quality of a resource
affecting usage
• International public concern

Receptor Sensitivity
For this EP, receptors are grouped into the following primary categories (as described
further in Section 7.0 and further broken down into sub-categories):
• Physical environment
• Biological environment
• Socio-economic and cultural environment.
Receptor sensitivity criteria are based on the following key factors:
• Importance of the receptor at local, national or international level – for instance, a
receptor will be of high importance at international level if it is categorised as a
designated protected area (such as a Ramsar site). Areas that may potentially contain
high value habitats are of medium importance if their presence/extent have not yet been
confirmed.
• Sensitivity/vulnerability of a receptor and its ability to recovery – for instance, certain
species could adapt to changes easily or recover from an impact within a short period of
time. As part of the receptor sensitivity criteria (Table 9-3) professional judgement
considers recovery time of a receptor from identified impacts. This also considers if the
receptor is under stress already.
• Sensitivity of the receptor to certain impacts – for instance, flaring emissions will
potentially cause air quality impacts and do not affect other receptors such as seabed.

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Table 9-3: Receptor Sensitivity Criteria

Sensitivity Environmental Impact

L Receptor with low value or importance attached to them, e.g. habitat or

species which is abundant and not of conservation significance, or
immediate to short-term recovery and easily adaptable to changes.

M Receptor of Medium importance, e.g. recognised as an area/species of

potential conservation significance for example, KEF or listed threatened
species, or
Recovery within 1–2 years following cessation of activities, or localised
medium-term degradation with recovery in 2–5 years.

H Receptor of High importance, e.g. recognised as an area/species of

potential conservation significance with development restrictions for
example marine parks or conservation reserves, or habitat critical to the
survival of a species, or
Recovery not expected for an extended period (> 5 years following
cessation of activity) or that cannot be readily rectified.

Impact Consequence Ranking

The magnitude of the impact and sensitivity of receptor are then combined to
determine the impact consequence ranking in accordance with Table 9-4 below. Key
management controls are subsequently identified to reduce the magnitude for such an
event occurring in order to determine the final residual impact ranking.

Table 9-4: Impact Consequence Ranking Matrix

Sensitivity
Residual Impact
L M H
Consequence Ranking Residual Impact Acceptability Categories
Positive Impact
+1 Consequence

0 No Impact Consequence Inherently acceptable - Manage for continuous improvement

through effective implementation of the HSSE and SP
Slight Impact
-1 management system
Consequence
Magnitude

Minor Impact
-2
Consequence
Moderate Impact Acceptable with controls - Apply the hierarchy of control to
-3
Consequence reduce the risks to ALARP
Major Impact
-4
Consequence
Unacceptable
Massive Impact
-5
Consequence

Unplanned Risks (Addition of Likelihood Criteria)

For unplanned/emergency events, the likelihood of such an event occurring also
requires assessment in association with the impact consequence to determine the risk
ranking. For example, based on magnitude and sensitivity alone, a hydrocarbon spill
associated with a long-term well blowout would be classed as having a major impact ;
However, the likelihood of an event occurring would typically be in the range of unlikely

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to remote. In addition, the mitigation measures for such impacts focusses on reducing
the likelihood of the impact occurring as opposed to reducing the magnitude of the
impact itself. Unplanned events also require assessment in terms of residual risk.
As with planned activities, the potential impacts of unplanned events are initially
identified, and the impact consequence ranking is determined, which inherently takes
into account the magnitude of the event and sensitivity of the relevant receptor(s). The
impact consequence ranking is then combined with the likelihood of the event occurring
(Table 9-5) in order to determine the overall environmental risk ranking via Table 9-6.
Controls are then identified to reduce the risk of such an event occurring in order to
determine residual risk.

Table 9-5: Likelihood Criteria

• Never heard of in the industry – extremely remote

A
• < 10-5 per year
• Has never occurred within the industry or similar industry but theoretically
possible
• Heard of in the industry – remote
B
• 10-5 – 10-3 per year
• Similar event has occurred somewhere in the industry or similar industry but
not likely to occur with current practices and procedures
• Has happened in the Company or more than once per year in the industry –
C unlikely
• 10-3 – 10-2 per year
• Event could occur within lifetime of similar facilities. Has occurred at similar
facilities
• Has happened at the location or more than once per year in the Company –
D possible
• 10-2 – 10-1 per year
• Could occur within the lifetime of the development
• Has happened more than once per year at the location – likely
E
• 10-1 – > 1 per year
• Event likely to occur more than once at the facility

Table 9-6: Environmental Risk Matrix (Unplanned Events)

Likelihood
A B C D E Residual Risk Acceptability Categories
Light Inherently Acceptable - Manage for
No Impact Consequence
Residual Impact Consequence

Blue continuous improvement through effective

Dark implementation of the HSSE and SP
Slight Impact Consequence management system
Blue

Minor Impact Consequence Yellow Acceptable with Controls - Apply the

hierarchy of control to reduce the risks to
Moderate Impact
Red ALARP
Consequence

Major Impact Consequence Red - X Unacceptable

Massive Impact
X X X
Consequence

For the purpose of the Prelude petroleum activities risk review, the following key risks
were assessed in accordance with the risk-based approach summarised in this section:

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• Vessel movements, in the context of unplanned interactions with marine fauna

• IMS
• Atmospheric emissions
• Greenhouse gas emissions
• Unplanned release of wastes
• Unplanned (spill) events.

9.2.3 Assessment of Residual Impacts and Risks

The risk assessment methodology applied ensured the following key steps were completed
throughout scenario development:
1. hazards identified
2. initiating causes determined
3. worst case credible scenarios agreed (without controls in place)
4. release of hazards understood (i.e. top events)
5. preventative controls listed
6. mitigative controls listed
7. likelihood determined (with confirmed controls in place)
8. risk ranking attributed.
In the evaluation of residual impacts and risks, all controls are assumed to be
implemented effectively and functioning as intended.
The residual impacts and risks detailed in Sections 9.3-9.14 represent a discussion of
the various sub-category environmental value/receptor rankings as determined. The
residual rankings displayed in the summary tables in the respective sections represents
the highest residual impact or risk for each primary receptor category where relevant
(i.e. physical environment, biological environment, and socio-economic/cultural
environment), and therefore can be considered a conservative assessment for some
individual environmental values/sensitivities. These residual impacts and risks are then
compared to the acceptability categories outlined in Section 8.0, Table 9-4 and Table
9-6 to determine a final ALARP and acceptability statement.
Cumulative environmental impacts and risks are also considered and discussed where
relevant through the impact and risk assessment process taking into account current
and foreseeable pressures on the environment including other petroleum activities,
other marine industries and users, and other ecosystem pressures.

9.2.4 ALARP Assessment

ALARP for Shell means, the point at which the cost (in time, money and effort) of
further risk or impact reduction is grossly disproportionate to the risk or impact
reduction achieved.
ALARP can be demonstrated through a number of mechanisms via:
• a quantitative method, such as via technical assessments (e.g. modelling studies) or
where the costs of the various options can be compared with the respective impact/risk
reduction

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• semi-quantitative method where impacts/risks within a certain level require a pre-defined

number of barriers of a certain effectiveness in place to prevent this hazard being
released, or via
• qualitative analysis, whereby ALARP is established using standards, legislative
requirements and judgement based on experience.
Shell applies the following hierarchy of control process to demonstrate ALARP as
shown in Figure 9-3.

Figure 9-3: Hierarchy of Controls

9.3 Physical Presence

9.3.1 Aspect Context

The physical presence of the Prelude FLNG facility, associated subsea infrastructure
and support vessels could potentially affect activities and access to areas associated
with fishing, tourism, defence, commercial shipping and the oil and gas industry in the
region. Refer to Section 6.0 for a description of the FLNG facility and supporting
activities/infrastructure.
A PSZ of 500 m has been established and gazetted around the FLNG mooring chain
touchdown locations and well centre (DC-1P), as per the OPGGS Act (NOPSEMA
2015), from which unauthorised marine users are prohibited from entering. The PSZ is
a key safety measure to reduce potential interactions with the FLNG facility and
associated subsea infrastructure. Temporary exclusion zones will be maintained
around any required vessel-based campaigns outside of the PSZ as required.

9.3.2 Description and Evaluation of Impacts

Socio-Economic Environment

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The expected impact of the Prelude activities on the fishing industry (commercial,
recreational and traditional), is expected in the worst-case scenario to be slight due to
the significant water depth and low fishing effort in the region and the limited extent of
the PSZ in relation to the area available for fishing.
There are no known tourism activities in the area due to the considerable water depths
and distance offshore. Therefore, no impacts to tourism are expected.
There are no known defence exercise areas or planned activities within the Operational
Area. Therefore, no impacts to defence are expected.
The closest permanent petroleum infrastructure to WA-44-L are the Ichthys facilities
about 20 km south of the Operational Area. Exploration activities undertaken by other
operators in the region within other permit areas are also possible and likely however,
Prelude petroleum activities are not expected to affect these.
Commercial shipping activity in the vicinity of the Operational Area is high and the
Prelude petroleum activities are not expected to significantly affect these other
activities associated with the Ichthys facility. Overall, the worst-case residual impact
ranking is assessed as Slight (Magnitude -1, Sensitivity L).

9.3.3 Impact Assessment Summary

Table 9-7: Physical Presence Evaluation of Residual Impacts

Consequence
Sensitivity
Magnitude

Residual
Environmental Receptor

Evaluation – Planned Impacts Impact

Socio-Economic Environment -1 L Slight

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9.3.4 ALARP Assessment and Environmental Performance Standards

Table 9-8: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Standard Criteria
(EPS)
Elimination N/A N/A Physical Presence cannot be eliminated for Prelude N/A N/A N/A
activities.
Substitution N/A No additional or alternative control measures have
N/A N/A N/A N/A
been identified for this risk for the Prelude activities.
Engineering N/A No additional or alternative control measures have
N/A N/A N/A N/A
been identified for this risk for the Prelude activities.
Administrative For specific vessel based Yes Allows notifications to be made to other marine 1.1 AHS is given notification in Records available
and Procedural campaigns, the Australian users in the area to minimise disruption to their advance to enable a ‘Notice to of advance
Controls Hydrographic Service (AHS) is activities. A ‘Notice to Mariners’ may be issued by Mariners’ to be issued prior to notification to the
given advance notification before the relevant authority before the activity. However, vessel based petroleum AHS which
arrival on location to enable a routine activities undertaken by support vessels to activities outside of the PSZ enables issuing
‘Notice to Mariners’ to be issued existing offshore infrastructure or facilities do not but within the Operational of Notice to
prior to petroleum activities warrant promulgation of a ‘Notice to Mariners’. Area. Mariners’ or the
outside of the PSZ but within the Similarly, activities occurring within NOPSEMA’s relevant Notice to
Operational Area. gazetted PSZs do not require promulgation of a Mariners.
‘Notice to Mariners’.

Administrative Stakeholder engagement Yes Consultation with relevant stakeholders has been 1.2 Disruption to other marine Stakeholder
and Procedural undertaken during the preparation of the EP and is users will be managed during engagement
Controls ongoing. Shell will ensure all Relevant Persons are ongoing stakeholder records
provided with sufficient information and have the consultation.
opportunity to raise any objections or claims
regarding potential disruption from Prelude
operations.
Administrative PSZ Yes A PSZ of 500 m has been established and gazetted 1.3 Compliance with PSZ as per Gazette notice of
and Procedural around the FLNG mooring chain touchdown Section 616 of the OPGGS PSZ
Controls locations and well centre (DC-1P), in accordance Act.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Standard Criteria
(EPS)
with the OPGGS Act (NOPSEMA 2015). Incident report
Unauthorised marine users are prohibited from form used to
entering the PSZ and therefore it is a key safety record breaches
measure to reduce potential interactions with the of PSZ
FLNG facility and associated subsea infrastructure. requirements.
Administrative Reduce size of the PSZ No A smaller PSZ would result in a smaller area from N/A N/A N/A
and Procedural which other marine users are displaced. However,
Controls the size of the PSZ is determined by legislation
(OPGGS Act) and therefore it is not able to be
reduced. In relation to available space in WA-44-L,
the PSZ represents a small portion of total navigable
space.

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9.3.5 Acceptability of Impacts

Table 9-9: Acceptability of Impacts – Physical Presence

Receptor Receptor Acceptable Level of Are the Acceptability

Category Sub-category Impact Impacts of an Assessment
Acceptable
Level?
Socio- Fishing No interference with Yes Shell considers the
economic and Industry fishing to a greater enforcement of permanent
Cultural extent than is exclusion of activities other
Environment necessary for the than Shell-authorised
exercise of right petroleum activities in the
conferred by the titles PSZ as legally binding and
granted to carry out safer for both the other
petroleum activities. marine users and Shell.
Furthermore, additional
Tourism and No negative impacts to Yes temporary exclusions of
Recreation nature-based tourism such users from the
resources resulting in Operational Area and
demonstrated loss of potentially its immediately
income. adjacent waters (e.g. due
Defence No interference with Yes to the physical presence of
defence activities as specific campaigns and the
directed by the FLNG facility and support,
Department of supply and product
Defence. offloading vessels) is
considered to be
Shipping No interference with Yes acceptable and necessary
navigation to a greater from a safety, security and
extent than is oil spill prevention
necessary for the (collision) perspective.
exercise of right Permanent displacement
conferred by the titles with the gazetted PSZ will
granted to carry out be managed through
petroleum activities. consultation with Relevant
Oil and Gas No interference with Yes Persons and designation
Industry other titleholders to a on Australian Hydrographic
greater extent than is Office nautical charts.
necessary for the
exercise of right
conferred by the titles
granted to carry out the
petroleum activities.

The assessment of impacts from physical presence determined the residual impact
rating of slight (Table 9-4). As outlined above, the acceptability of the impacts from
physical presence associated with the petroleum activities has been considered in the
following context.
Principles of ESD
The impacts from physical presence are consistent with the principles of ESD based on
the following points:
• The physical presence aspect does not degrade the biological diversity or ecological
integrity of the Commonwealth marine area in the Browse Basin.
• Significant impacts to MNES will not occur.

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• The health, diversity and productivity of the marine environment will be maintained for
future generations.
• The project does not significantly impinge upon the rights of other parties to access
environmental resources (e.g. commercial and traditional fishers).
• The precautionary principle has been applied, and studies undertaken where knowledge
gaps were identified. This knowledge has been applied during the evaluation of
environmental impacts and risks.
Relevant Requirements
Management of the impacts from physical presence are consistent with relevant
legislative requirements, including:
• Section 616 of the OPGGS Act
• Compliance with international maritime conventions, including:
o STCW Convention
o SOLAS Convention
o COLREGS.
• Compliance with Australian legislation and requirements, including:
o Navigation Act 2012:
 Marine Order 21 (Safety of Navigation and Emergency Procedures)
 Marine Order 30 (Prevention of Collisions)
 Marine Order 71 (Masters and Deck Officers).

Matters of National Environmental Significance

Threatened and Migratory Species
The evaluation of impacts from the physical presence of the Prelude FLNG facility,
associated subsea infrastructure and marine vessels indicates no potential for
significant impacts to threatened and migratory species.
Commonwealth Marine Environment
The evaluation of impacts from the physical presence of the Prelude FLNG facility,
associated subsea infrastructure and marine vessels indicates significant impacts to
the Commonwealth Marine Environment are not credible.
External Context
There have been no objections or claims raised by Relevant Persons to date around
the physical presence aspect. Shell’s ongoing consultation program will consider
statements and claims made by stakeholders when undertaking the assessment of
impacts.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and Environmental, Social and Health Impact Assessment (ESHIA) requirements. The
EPO and the controls which will be implemented, are consistent with the outcomes
from stakeholder consultation for the Prelude FLNG facility and Shell’s internal
requirements.
Acceptability Summary
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The assessment of impacts and risks from physical presence determined the residual
impact rankings were slight or lower (Table 9-4 Impact Consequence Ranking Matrix).
As outlined above, the acceptability of the impacts have been considered in the context
of:
• The established acceptability criteria for the physical presence aspect
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
Shell considers residual impacts of slight or lower to be acceptable if they meet
legislative and Shell requirements. The discussion above demonstrates that these
requirements have been met in relation to the physical presence aspect.
Based on the points discussed above, Shell considers the impacts from physical
presence associated with the Prelude petroleum activities to be ALARP and
acceptable.

9.3.6 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

No adverse interactions between Prelude No supported claims reported which

activities and other marine users. demonstrate direct loss of income or other
Displacement of other marine users is impacts to marine users as a result of
limited to the PSZ and any temporary undertaking the petroleum activities.
displacement due to vessel-based
campaigns.

9.4 Lighting

9.4.1 Aspect Context

The Prelude FLNG facility and supporting activities require 24-hour external
illumination to meet maritime and operational safety standards. Artificial light emissions
are generated from two primary sources:
• Navigational and operational lighting required for safe function of the FLNG facility and
supporting vessels
• Flaring activities from the FLNG facility either from the constantly lit pilot light or during
intermittent flaring events as described in Appendix A: Detailed Facility Description.

9.4.2 Description and Evaluation of Impacts

Lighting can create light spill, which has the potential to impact on marine fauna
populations for animals that show avoidance or attraction to lights by potentially
changing navigational cues that ultimately affect energy expenditure or alter predation
and/or feeding rates. Impacts may include the following:

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• Disorientation, misorientation, attraction or repulsion

• Disruption to natural behavioural patterns and cycles
• Secondary impacts such as increased predation
• Reduced fitness.

Biological Environment
Reptiles
Of the turtle species identified as protected under the EPBC act, only green turtles
(Scott-Browse Stock) are known to nest on Browse Island (~ 40km to the southeast of
the Prelude FLNG Project area), with important internesting habitat located within
~20km of Browse Island (Commonwealth of Australia 2017).
Light pollution on nesting beaches can alter critical nocturnal behaviours in adult and
hatchling turtles (Commonwealth of Australia 2019). Research suggests that artificial
lighting can disrupt or affect the choice of nesting location by female turtles, particularly
light visible on the landward side of nesting beaches (Salmon 1992). Turtle hatchlings
leaving nesting beaches are particularly sensitive to artificial lighting as they use
celestial cues to orientate (Limpus 2008, Salmon et al. 1992; cited in Lorne et al. 1997).
Marine turtle hatchlings may use celestial lights as navigational markers during oceanic
migrations and are attracted towards bright lights. Hatchlings can become disorientated
and trapped within light spill around platforms and vessels, resulting in increased
energy expenditure, increased predation and decreased survival rates (Witherington &
Martin 1996; cited in Lorne et al. 1997; Commonwealth of Australia 2019). However, as
hatchlings swim offshore from their natal beach, they become less influenced by light
cue and rely predominantly by wave motion, currents and the earth’s magnetic field
(Lohmann and Lohmann 1992).
The table below indicates the extent of visibility of the lighting from the Prelude FLNG
facility with respect to turtles (ERM 2009b).

Table 9-10: Line of Sight Limits for Turtles

Light Source Marine Turtles

(limit of light visibility)
Flare (when operating) 51km
Topsides (Process Facilities) 27km
Sky glow from combined Effects expected to be minimal
luminaries given the low levels of particulate
matter in the air offshore

Vessels have lower deck height than the FLNG facility therefore, the line-of-sight
assessment undertaken for the FLNG facility suffices for the impact assessment. Even
if the FLNG facility is visible, it would only be visible on the seaward horizon and
unlikely to alter hatchlings journey from the dunes towards the ocean.
Extensive light attraction studies have been conducted on turtle hatchlings, including at
Barrow Island (Pendoley 2005), approximately 1,000 km southwest of the Operational
Area. These studies demonstrated that hatchlings crawl away from tall, dark horizons

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(sand dunes and vegetation) towards lower and lighter horizons (the sea and stars),
and that artificial lighting can alter this response.
Turtles in the nearshore or on the beaches of Browse Island may be able to see the
lighting of the Prelude FLNG facility especially during flaring events but this is not
expected to have an adverse impact to nesting turtles or hatchlings given the ~40 km
separation distance. The flare is potentially visible from the northern beaches of
Browse Island low on the seaward horizon with an expected intensity less than that
presented by a quarter moon (Imbricata 2018). As the flare is low on the horizon, the
Island’s landmass blocks light from the flare to the southern beaches so that no
beaches on Browse Island are subjected to light from the flare on their landward
horizon and the landward horizons remain unaltered to nesting and hatchling turtles.
Furthermore, at the date of writing this EP there have been no recorded instances of
turtle hatchling sightings or aggregations around the FLNG.
Once in the water, hatchling navigation is influenced predominantly by wave motion,
currents and the earth’s magnetic field. There is no expected impact of lighting from
Prelude activities on hatchlings once in the water.
Studies also suggest that light generated by flares may not affect hatchlings as much
as other light sources. Witherington and Bjorndal (1991) examined the roles of light
wavelength and intensity in the sea-finding mechanisms of loggerhead and green turtle
hatchlings and found the most disruptive wavelengths to be in the range of 300 to 500
nanometres (nm) (blue – green wavelengths). Spectral analysis of flares at Thevenard
Island (Pendoley 2000) suggests that flare light typically does not contain a high
proportion of light wavelengths within this range.
There are no important habitat for listed turtle species that are known to be affected by
artificial light within 20km of the Operational Area. Important habitats are those areas
necessary for an ecologically significant proportion of a listed species to undertake
important activities such as foraging, breeding, roosting or dispersal. The applied
20 km threshold is in alignment and provides a precautionary limit based on observed
effects of sky glow on marine turtle hatchlings demonstrated to occur at 15-18 km
(Commonwealth of Australia 2019). Therefore, any light generated from within the
Operational Area will not result in any environmental damage or effects given the
separation distance to the nearest sensitive habitats as follows:
• 23 km to the Green Turtle critical internesting habitat
• 40 km to Browse Island – Turtle nesting and hatchlings.
Given the limited amount of flaring that is expected to occur during normal operations,
the large separation distance of the Prelude FLNG facility from Browse Island and the
closest turtle critical habitat and the unaltered landward horizon at Browse Island, there
is no expected residual impact consequence from Prelude activities’ light spill on turtle
hatchlings and adult turtles (Magnitude 0, Sensitivity – M).
There is no literature available on the effects of light on sea snakes. However,
anecdotal evidence based on absence of observed sea snakes in waters in the
Operational Area suggest that sea snakes are not attracted to artificial light sources.
Birds
Studies conducted between 1992 and 2002 in the North Sea confirmed that artificial
light was the reason that birds were attracted to and accumulated around lit offshore
infrastructure (Marquenie et al. 2008) and that lights can attract birds from large
catchment areas (Wiese et al. 2001). Either birds may be attracted by the light source

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itself or indirectly as structures in deep water environments tend to attract marine life at
all trophic levels, creating food sources and shelter for birds (Surnam 2002). The light
from operating production facilities may also provide enhanced capability for birds to
forage at night. Negative potential impacts to birds attracted by artificial lighting are
limited but include collisions with infrastructure and alteration of normal behaviours
(Commonwealth of Australia 2019).
When considering line of sight with respect to light assessment for birds, the factors
that need to be considered include:
• the location and height of the light source (FLNG facility and flare)
• the distance between the light source and the receptor
• the potential elevation of the receptor (birds).
Migratory birds are known to fly at altitudes of between 150 and 600m. To be
conservative, the light assessment has used an elevation of 600m as the potential
maximum elevation of the migratory birds. Based on a potential flying height of 600m,
the light from the FLNG facility will be visible to birds out to a distance of approximately
151km when the flare is operational or 127km when the flare is not being used (ERM
2009b). Table 9-11 indicates the extent of visibility of the lighting from the FLNG with
respect to birds.

Table 9-11: Line of Sight Limits for Migratory Birds and Seabirds

Light Source Birds

(Limit of Light Visibility)
Flare (when operating) 151km
Topsides (Process Facilities) 127km
Sky glow from combined Effects expected to be minimal
luminaries given the low levels of particulate
matter in the air offshore

If migratory birds are reliant on visual cues in addition to their magnetic compass, such
as ambient light, moonlight and starlight to navigate, then artificial light could alter their
natural migratory patterns, particularly in the absence of terrestrial landmarks. Light
emissions from offshore platforms in the North Sea have been shown to attract
migrating birds and birds that migrate during the night are especially affected
(Verheijen 1985). During other studies conducted in the North Sea (Marquenie et al.
2008), it was noted that birds travelling within a 5km radius of illuminated offshore
platforms may deviate from their intended route and either circle or land on the nearby
platform. Beyond this distance, it is assumed that light source strengths were not
sufficient to attract birds away from their preferred migration route.
Injuries and mortalities to birds occur through direct collisions with infrastructure and
the rate of collision is (as inferred from literature) relates to weather conditions, the
cross-sectional area of the obstacle, amount of light and number of birds travelling
through an area. Where bird collision incidents have been reported, low visibility
weather conditions (cloudy, overcast and foggy nights) have usually been implicated as
the major contributing factor, in contrast there are seldom collision incidents on clear
nights (Avery 1976; Elkins 1988; Weise et al. 2001). It should be noted that conditions
in the Operational Area are not conducive to significant fog formation, however most
rainfall is seasonal associated with summer monsoon and cyclones in November to

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April which does overlap with the peak migratory period for birds as indicated in
Section 7.2.8.3 Seasonal Sensitivities of Threatened Species.
According to Bamford et al. (2008), 33 species of migratory birds that use the East
Asian-Australian Flyway (EAAF) are regularly present within Australia. The EPBC listed
streaked shearwater was not identified as using the EAAF in Bamford’s study.
Migratory shorebird species are mostly present in Australia during the non-breeding
period, from as early as August to as late as April/May each year (DoEE 2017b) As
defined previously, the documented zone of impact for migratory birds that resulted in a
recorded change in natural behaviour (Marquenie et al. 2008) is two orders of
magnitude smaller than the limit of visibility, at a radius of 5 km from an artificial light
source.
There are no important habitats for listed bird species that are known to be affected by
artificial light within 20 km of the Operational Area. Important habitats are those areas
necessary for an ecologically significant proportion of a listed species to undertake
important activities such as foraging, breeding, roosting or dispersal. The applied
20 km threshold provides a precautionary limit based on observed effects of sky glow
on fledgling seabirds grounded in response to artificial light 15 km away
(Commonwealth of Australia 2019). Therefore, any light generated from within the
Operational Area will not result in any environmental damage or effects given the
separation distance to the nearest sensitive habitats as follows:
• 59km to the nearest bird breeding BIA.
It is considered possible that small numbers of mature birds may be attracted to the
lighting of the FLNG facility. Within the first two years of the FLNG being on location in
the Operational Area, there had been recorded observations of one live bird resting on
the FLNG and 8 deceased birds of unknown cause, none of which were listed as
Threatened. Even if all the recorded birds could be attributed to a single species with
lighting as the key cause, this number would represent a very low proportion of the total
number of birds that would have flown through the area within the same timeframe and
would be well below what would be considered an ecologically significant proportion.
Therefore, it is concluded that under the worst-case conditions, there are no expected
residual impact consequence (Magnitude – 0, Sensitivity – M).
Pelagic Communities
Fish and zooplankton may be directly or indirectly attracted to lights. Experiments using
light traps have found that some fish and zooplankton species are attracted to light
sources (Meekan et al. 2001), with traps drawing catches from up to 90 m (Milicich et
al. 1992). Lindquist et al. (2005) concluded from a study of larval fish populations
around an oil and gas platform in the Gulf of Mexico that an enhanced abundance of
clupeids (herring and sardines) and engraulids (anchovies), both of which are highly
photopositive, was caused by platform light fields.
The concentration of organisms attracted to light results in an increase in food source
for predatory species and marine predators are known to aggregate at the edges of
artificial light halos. Shaw et al. (2002), in a similar light trap study, noted that juvenile
tunas (Scombridae) and jacks (Carangidae), which are highly predatory, may have
been preying upon concentrations of zooplankton attracted to the light field of the
platforms. This could potentially lead to increased predation rates compared to unlit
areas. The intensity of lights may potentially result in a concentration of some marine
fauna, although for a period of approximately two years there have been no recordings
of significant aggregations of marine fauna from when the FLNG first arrived on
location.
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The potential for increased predator activity is unlikely to result in a significant impact
on the plankton or fish populations. Given the relatively small impact area surrounding
the petroleum activities in respect to zooplankton and fish habitat, the potential impacts
are expected to be highly localised and unlikely to have discernible consequences at
the population level. The distances from Prelude to the closest island (Browse Island)
and shoal (Echuca Shoal) are approximately 40 km and 61 km from the Operational
Area respectively. Therefore, it is unlikely that artificial lighting will impede or disturb
natural lighting cycles that may affect coral spawning.
The range of attraction for fish and invertebrates to lighting from the FLNG facility and
support vessels is expected to be localised with no discernible residual impact
consequence (Magnitude – 0, Sensitivity - L) and is not expected to attract individuals
away from any named shoals/banks, offshore reefs/islands or KEFs. Considering a low
receptor sensitivity to such impacts, there are no credible residual impacts at a
population level.

9.4.3 Impact Assessment Summary

Table 9-12 lists the highest impact consequence rating in the relevant environmental
receptor groups.

Table 9-12: Light Emissions Evaluation of Impacts

Residual Impact
Consequence
Sensitivity
Magnitude

Environmental Receptor

Evaluation – Planned Impacts

Physical Environment N/A N/A N/A
Biological Environment 0 M No Impact
Socio-Economic Environment N/A N/A N/A

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9.4.4 ALARP Assessment and Environmental Performance Standards

Table 9-13: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmenta Measurement

Controls l Performance Criteria
Standard
(EPS)

Elimination No lighting N/A No additional or alternative control measures have N/A N/A N/A
been identified for this impact for the Prelude
activities, given the requirement for a well-lit work
area.
Elimination No flaring No Occasional flaring is necessary for safe operations. N/A N/A N/A
Collection of all flared gas (including pilot and purge)
would entail significant cost with the corresponding
environmental benefit grossly disproportionate to the
additional cost. Flare minimisation is one of the key
controls for minimising GHG emissions (see Section
9.11).
Substitution Use different wavelength lights No During the Design Phase of the FLNG facility a N/A N/A N/A
lighting assessment was undertaken and the cost
comparison indicated as much as 163% extra cost
for the changing the lighting to different wavelength
lights. Given the low densities of migratory birds and
seabirds that may pass through the project area,
and that the lighting risk assessment indicates that
the impacts to birds and turtles will be nil, it was
concluded that installing different spectrum lighting
was not demonstrably ALARP for Prelude.
Engineering Lighting of the FLNG designed to No The use of low-spill/directional and shielded lighting N/A N/A N/A
minimise light spill via: is not warranted due to the distance of the FLNG
Shielding; from the nearest turtle nesting beach (approximately
Use low spill/ directional lighting; 40km from Browse island) and bird rookery
Use of low-reflective paints; (approximately 162km from Ashmore Reef National
Directing luminaires inwards on

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Hierarchy of Control Measure Adopted? Justification EPS # Environmenta Measurement

Controls l Performance Criteria
Standard
(EPS)
the FLNG facility and away from Nature Reserve) and the absence of other light-
the ocean. sensitive fauna around the FLNG location.
Administrative No additional or alternative control measures have N/A N/A N/A
and Procedural been identified for this impact for the Prelude
controls activities, given the requirement for a well-lit work
area.

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9.4.5 Acceptability of Impacts

Table 9-14: Acceptability of Impacts - Lighting

Receptor Receptor Acceptable Level of Are the Acceptability Assessment

Category Sub- Impact Impacts of
category an
Acceptable
Level?
Physical N/A N/A N/A N/A
Environment
Biological Threatened No significant impacts Yes Light from the FLNG and
Environment and to listed Threatened support vessels may attract
Migratory (Endangered and threatened and migratory
Species Vulnerable) or birds, which may roost on the
Migratory MNES fauna structures. Given there are no
populations. important habitats within 20 km
Management of of the facilities (20 km being a
aspects of the project conservative threshold
must be aligned to distance for impacts), light
conservation advice, emissions are not expected to
recovery plans and result in significant impacts at
threat abatement a population level. Light
plans, including for emissions are not anticipated
bird and marine turtle to have a significant impact on
species. marine turtle species given the
separation distance of the
facilities from any sensitive
habitat and are therefore not
inconsistent with the
requirements of the relevant
recovery plan.
Pelagic No significant adverse Yes The range of attraction for fish
communities effect on pelagic and invertebrates to lighting
(Non- communities, from the FLNG facility is
Threatened populations, habitats expected to be localised and
or or spatial distribution no discernible impacts are
Migratory) of a species. expected. The facility is also
not expected to attract
individuals away from any
named shoals/banks, offshore
reefs/islands or KEFs.
Considering a Low receptor
sensitivity to such impacts,
there is no credible potential
for residual impacts at a
population level.

Socio- N/A N/A N/A N/A

economic
and Cultural
Environment

The assessment of impacts from light emissions determined no residual worst-case

impact (Table 9-12). As outlined above, the acceptability of the impacts from light
emissions associated with Prelude operations has been considered in the following
context.
Principles of ESD

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The impacts from light emissions are consistent with the principles of ESD based on
the following points:
• The light emissions aspect does not degrade the biological diversity or ecological
integrity of the Commonwealth Marine Area and significant impacts to MNES are not
anticipated to occur.
• The precautionary principle has been applied, and studies/reviews undertaken (ERM
2009b; Imbricata 2018) where knowledge gaps were identified. This knowledge has
been applied during the evaluation of environmental impacts.
Relevant Requirements
Management of impacts from light emissions are consistent with relevant legislative
requirements, including:
• Draft National Light Pollution Guidelines for Wildlife Including marine turtles, seabirds
and migratory shorebirds (Commonwealth of Australia 2019).
• Management of impacts are consistent with policies, strategies, guidelines, conservation
advice, and recovery plans for threatened species (Table 9-15).
• Implementation of recognised industry standard practice, such as minimisation of flaring.

Matters of National Environmental Significance

Threatened and Migratory Species
The evaluation of lighting impacts indicates significant impacts to threatened and
migratory species will not credibly result from the light emissions aspect of Prelude
FLNG operations.
Alignment of Prelude operations with management plans, recovery plans and
conservation advice for threatened and migratory fauna is provided in Table 9-15.
Commonwealth Marine Environment
The impacts from the light emissions aspect of Prelude operations on the
Commonwealth marine environment will not exceed any of the significant impact
criteria provided in Table 8-1.

Table 9-15: Summary of Alignment of the Impacts from Light Emissions Aspect of the
Prelude field with Relevant Requirements for EPBC Threatened Fauna

Matters of MNES Acceptability Demonstration of Alignment as Relevant to the Project

National Considerations
Environmental (Significant Impact
Significance Criteria, EPBC
Management
Plans/Recovery
Plans/Conservation
Advices)
Threatened Significant impact criteria The evaluation of environmental impacts indicates that impacts
and Migratory for Critically Endangered, from artificial light emissions on threatened or migratory species
species - Birds Endangered, Vulnerable are likely to be minor and would not constitute a significant impact
and Migratory species to populations. As such, residual impacts from artificial light
(Table 8-1) associated with Prelude operations does not exceed any of the
significant impact criteria for Threatened and Migratory marine
species provided in Table 8-1.

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Wildlife Conservation Managing the light aspect of Prelude operations has been aligned
Plan for Migratory to ‘Objective 4’ of the Plan by ensuring that anthropogenic
Shorebirds (DoE 2015a) disturbance was considered in development assessment
processes. Migratory birds have been considered as an
environmental receptor in the evaluation of lighting impacts.
Draft National Light Seabirds and migratory birds have been identified in the draft
Pollution Guidelines for National Light Pollution Guidelines to be affected by artificial light
Wildlife (Commonwealth sources. The management of light emissions for Prelude
of Australia 2019). operations has considered the light management actions
described in the guidelines and the impact assessment/thresholds
have been based on the precautionary limits referenced in the
guidelines (Section 9.4.2).
Threatened Significant impact The evaluation of environmental impacts indicates that impacts
and Migratory guidelines for Critically from artificial light emissions on threatened or migratory marine
species - Endangered, reptiles are slight and would not constitute a significant impact. As
Marine Reptiles Endangered, Vulnerable such, residual impacts from artificial light associated with Prelude
and Migratory species operations do not exceed any of the significant impact criteria for
(Table 8-1) Threatened and Migratory marine reptile species provided in Table
8-1.
Recovery Plan for Marine Light pollution has been identified as a threat in the Recovery Plan
Turtles (Commonwealth for Marine Turtles (Commonwealth of Australia 2017). Nesting
of Australia 2017) females and hatchling turtles are at greatest risk of light impacts;
however, the nearest potential nesting habitat is Browse Island
(approximately 40 km from the FLNG). Potential light-related
impacts to turtles on nesting beaches is slight.
Actions in the Recovery Plan for Marine Turtles (Commonwealth of
Australia 2017) relating to the threat of artificial light include:
• Artificial light within or adjacent to habitat critical to the survival
of marine turtles will be managed such that marine turtles are
not displaced from these habitats
• Develop and implement best practice light management
guidelines for existing and future developments adjacent to
marine turtle nesting beaches
• Identify the cumulative impacts on turtles from multiple sources
of onshore and offshore light pollution
Given the Operational Area is beyond any BIAs or habitat critical
for the survival of marine turtles (e.g. nesting, inter-nesting or
foraging areas) and the light modelling and other studies indicate
that impacts to marine turtles will be nil, the actions listed above
are not applicable to Prelude operations.
Draft National Light Marine turtles have been identified in the draft National Light
Pollution Guidelines for Pollution Guidelines to be affected by artificial light sources. The
Wildlife (Commonwealth management of light emissions for Prelude operations has
of Australia 2019). considered the light management actions described in the
guidelines and the impact assessment/thresholds have been
based on the precautionary limits referenced in the guidelines
(Section 9.4.2).
Commonwealth Significant Impact The evaluation of environmental impacts indicates that the light
marine area Guidelines for the emissions aspect of Prelude operations will not exceed the
Commonwealth marine Commonwealth marine environment significant impact criteria
environment (Table 8-1) provided in Table 8-1.

External Context
There have been no objections or claims raised by Relevant Persons to date around
the lighting aspect. Shell’s ongoing consultation program will consider statements and
claims made by stakeholders when undertaking the assessment of impacts and risks.

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Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements.
Acceptability Summary
The assessment of impacts and risks from light emissions determined the residual
impact ratings were Nil (Table 9-12) given that any visible light (including sky glow) will
not displace or disrupt any MNES listed species from important habitat, nor will it
prevent these species from being able to undertake critical behaviours such as
foraging, reproduction and dispersal. Shell considers residual impacts of nil to be
acceptable if they meet legislative and Shell requirements. To this effect, the
acceptability of these impacts have been considered in the context of:
• The established acceptability criteria for the light emissions aspect
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).

Based on the discussion of these considerations presented above, Shell considers

impacts from light emissions associated with Prelude operations to be acceptable.

9.4.6 Environment Performance Outcomes

Environment Performance Outcome Measurement Criteria

No injury or mortality of listed Fauna observations and incident reports

Threatened or Migratory MNES species demonstrate no mortality of listed
as a result of artificial light emissions. Threatened species as a result of artificial
light emissions.
Management of artificial light emissions
associated with the project must be
aligned to conservation advice,
recovery plans and threat abatement
plans, including for bird and marine
turtle species.

9.5 Noise

9.5.1 Aspect Context

Airborne and marine noise emissions from Prelude operations are generated from the
following operational sources and activities:
• Subsea infrastructure including wells, pipelines and risers
• Supply and other marine vessel (e.g. ASV during maintenance) operations

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• Power Generation and Production Process at the FLNG vessel, including Flaring
• Product Offtake Operations including Tanker Arrival, Loading and Departure
• Helicopter Operations
• Subsea Inspection, Maintenance and Repair (IMR) works.

Subsea Infrastructure
The broadband noise produced by an operational wellhead is very low, 113 dB re 1
µPa, which is only marginally above rough sea condition ambient noise (McCauley,
2002). For this noise level to be exceeded, there would need to be multiple wellheads
within a very close proximity of each other (approximately less than 50 m apart) before
their signals combine to increase the total noise field (with two adjacent sources only
increasing the total noise field by 3 dB). Hence for Prelude field wellheads, the
broadband noise level in the vicinity of the wellheads would be expected to be of the
order of 113 dB re 1 µPa and this would fall to background levels within less than 200
m from the wellhead (McCauley, 2002). Similar to wellhead noise, which includes flow
noise in pipelines, the noise field produced along a pipeline/flowline may be expected
to be very close in levels to that described for wellheads, with the radiated noise field
falling to ambient levels within approximately a hundred meters. Hence noise impacts
from subsea infrastructure including wellheads and flowlines are not considered
credible and will not be discussed further.
Subsea IMR activities are typically undertaken from vessels that use a Dynamic
Positioning (DP) system. This allows manoeuvrability, station keeping and avoids
anchoring when undertaking works near subsea infrastructure. As the vessel will
maintain its position with the continual use of DP thrusters, the thrusters will dominate
as the source of underwater noise. Noise generated from these activities will be
intermittent and of short duration and like the noise produced by other marine vessels
in the field (e.g. supply boats).
Subsea inspections generally involve the IMR vessel travelling along the route of the
subsea system with an ROV to identify or undertake maintenance or repair activities
that may be required to ensure the assets are being maintained. Inspection techniques
with the potential to generate underwater noise include side-scan sonar. Sonars are
used in relatively shallow water depths (70 to 240 m) to detect objects on the sea floor
including existing infrastructure and potential seabed hazards, however their use will be
occasional only, e.g. once every 1-3 years, and only for several weeks at a time. The
sonar operates at high frequencies (typically around 100–500 kHz) with the frequency
being dependent on the substrate type, resolution of data required, and water depth.
Supply and Other Marine Vessel Operations
During normal operations, support vessels may be required to complete routine round-
trip voyages between the Operational Area and Darwin or another Australian Port. The
underwater noise that is produced by vessels arises from two continuous sources –
propeller cavitation and the propulsion machinery (engines) inside the vessel.
Support vessels typically produce sound levels around 160-180dB re 1µPa at 1m
generally dominated by low frequencies during transit and drop with reduced speed. As
the ship’s speed increases, broad band noise such as propeller cavitation and hull
vibration noise become dominant over machinery related tones (NRC 2003). When
vessels are holding station, frequencies increase considerably with the use of thrusters

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to maintain position. A vessel using DP produces noise of low frequency, less than
1kHz, with broadband values up to 177dB re 1μPa at 1m (Simmonds et al. 2004)
Power Generation, Production and Product Offtakes
When the FLNG thrusters are not operating, the facility’s underwater noise signature is
dominated by the noise produced by the utilities (e.g. power generation) and production
facilities. These include the steam turbine generators, boilers, air compressors, and
pumps located within the hull and topsides process equipment including compressors
and motors. Other production related noise contributors include occasional
hydrocarbon flaring and continuous acid gas venting.
The resulting noise amplitudes from Prelude normal operations are predicted to peak at
50Hz, and the overall source level in the frequency range 10Hz to 2kHz is predicted to
be 189.1dB re1μPa at 1m. Figure 9-4 shows predicted maximum received noise levels
from FLNG facility plant as described.

Figure 9-4: Predicted Maximum Received Levels at Any Depth Due to Non-Offtake FLNG
Facility Noise as a Function of Range and Azimuth

The highest underwater noise levels will be experienced when the vessel’s thrusters
are used to maintain position. The requirement to use thrusters is determined by
weather conditions and may occur during the berthing and de-berthing of the product
offtake vessels and on occasions throughout the off-loading period. Thrusters may also
be required during helicopter operations.
The alongside offloading configurations for the LNG and LPG carriers may involve the
simultaneous operation of thrusters on the FLNG facility, thrusters on the two in-field
support vessels (acting as tugs), and the main engines of the berthing tanker.
Thrusters on the FLNG facility and tugs generate high levels of thrust in poor flow
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conditions, resulting in significant propeller cavitation and consequent high underwater

noise levels.
Predicted noise levels peak in the frequency range 200Hz to 400Hz. The
corresponding broadband source levels over 10Hz to 2kHz are predicted to be 189.1dB
re 1μPa at 1m for the FLNG facility, and 189.7dB re 1 μPa at 1m for the combined
effect of two tugs. If all sources are co-located, their combined source level is
estimated at 192.4dB re 1μPa at 1m. Figure 9-5 shows the maximum predicted
received level of noise at any depth as a function of range and azimuth for the different
sources during offtake operations, as well as their combined effect.

Figure 9-5: Predicted Maximum Received Levels at Any Depth due to Cavitation Noise.
Top Left FLNG Facility Only; Top Right: 2 x Tugs only; Bottom: Combined Effect of Tugs
and FLNG Facility. Note Change in Scale Compared to Previous Figure

Table 9-16 illustrates the maximum distances from Prelude at which noise levels from
normal operations and offtake operations are likely to be exceeded.

Table 9-16: Maximum Distance from FLNG at Which the Specified Received Levels are
Likely to be Exceeded

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Received Noise Level in Cavitation noise Plant noise during

10Hz to 2kHz band (dB re during offtake operations
1μPa) operations
160 60m 17m

150 200m 50m

140 850m 190m

130 3.7km 600m

120 9km 1.3km

110 17km 4.5km

100 30km 10km

90 44km 20km

Helicopter Operations
Helicopter flights are required from the operating base at Broome or from Djarindjin
(Lombadina) Airport to site for the purposes of crew change out. The main acoustic
source associated with helicopters is the impulsive noise from the main rotor. Dominant
tones in noise spectra from helicopters are generally below 500Hz (Richardson et al.
1995). The level of underwater sound from helicopters is affected by helicopter altitude,
aspect and strength of noise emitted, and the receiver depth, water depth and other
variables (Richardson et al. 1995).
The angle at which the line from the aircraft and receiver intersects the water surface is
important. In calm conditions, at angles greater than 13° from the vertical, much of the
sound is reflected and does not penetrate the water (Richardson et al, 1995).
Therefore, strong underwater sounds are detectable for a period roughly corresponding
to the time the helicopter is within a 26° cone above the receiver. Richardson
(Richardson et al, 1995) reports figures for a Bell 214 helicopter (stated to be one of
the noisiest) being audible in air for 4 minutes before it passed over underwater
hydrophones, but detectable underwater for only 38 seconds at 3 m depth and 11
seconds at 18 m depth. The maximum received level was 109 dB re 1µPa2. s. Due to
their short duration and near surface impacts only, helicopter noise emissions are not
considered to be a credible source of noise impact/ risk and will not be discussed
further.
Summary
Table 9-17 provides a summary of sound frequencies and sound levels expected from
noise sources produced by FLNG activities and support operations.

Table 9-17: Expected Sound Frequencies and Broadband Source Levels of FLNG and
Support Operations

Source Dominant Frequency Expected source levels

Range (Hz) (dB re 1μPa at 1m)

Support vessels 100 -2,000 164-182

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Source Dominant Frequency Expected source levels

Range (Hz) (dB re 1μPa at 1m)

Vessel using dynamic 50 - 1,000 177

positioning (DP)

Side Scan Sonar 100,000 – 500,000 no data

34m twin diesel work boat 630 159

Tug (pulling empty barge) 37 - 5,000 145 - 166

Tug (pulling loaded barge) 1,000 - 5,000 161 - 170

Prelude FLNG (normal < 2,000 (peak 50) 189.1 (10 - 2,000 Hz)
operations)

Prelude FLNG and offtake < 2,000 (peak 200-400) 192.4 (10 - 2,000 Hz)
tankers simultaneously using
thrusters

Helicopters < 500 Received levels at 3m water depth of

101-109dB for a Bell 212 helicopter at
an altitude of 610-152m respectively.

Source: Woodside Energy Limited 2011 and Shell 2009

Underwater Noise Impact Levels

Marine species with the greatest sensitivity to underwater noise are marine mammals
(whales and dolphins), turtles and fish (including larvae). Other species that could be
affected by underwater noise include sea snakes, sharks and rays and invertebrates.
Impacts to marine fauna can be grouped in the following decreasing order of effect:
• mortality or potential mortal injury – physical injury that may result in the death of an
animal
• impairment:
o permanent threshold shift (PTS) – a permanent reduction in the ability of an animal
to perceive sound. Recovery is not expected to occur.
o temporary threshold shift (TTS) – a temporary reduction in the ability of an animal to
perceive sound. Recovery to pre-exposure levels is expected to occur.
o masking – no change in the ability for an animal to perceive sound, but biologically
meaningful sounds may be “drowned out” by anthropogenic noise.
• behavioural impacts – typically short-term behavioural responses such as avoidance,
surfacing etc. Behaviour will return to normal following cessation of the anthropogenic
noise.

Impact thresholds for the fauna groups were derived from scientific literature and
published guidelines, including:
• Sound exposure guidelines for fishes and sea turtles: a technical report prepared by
American National Standards Institute (ANSI)-Accredited Standards Committee S3/SC1
and registered with ANSI (Popper et al. 2014).

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• Technical guidance for assessing the effects of anthropogenic sound on marine

mammal hearing (NOAA 2018).

Marine Mammals (Cetaceans)

The vulnerability of marine mammals to underwater noise is linked to their ability to
perceive sound. Cetaceans can be grouped based on similarities in their hearing.
Underwater noise exposure thresholds can then be weighted for each cetacean group
to emphasise noise frequencies that a group may be particularly vulnerable to. This
approach is described in Southall et al. (2007) and has been applied to a range of
underwater noise guidelines and impact assessments on cetaceans. The impact
thresholds for continuous (non-impulsive) 8 underwater noise are summarised in Table
9-18. These are derived primarily from technical guidelines published by NOAA (2018).

Table 9-18: Marine Mammal Sound Exposure Criteria (Continuous Noise)

Type of Animal Generalised PTS – Permanent TTS – Behaviour

Hearing Range1 Injury Impairment
[Hz] (received levels)2

Low-frequency cetaceans 7 – 35,000 199 dB LE/p, 24h 179 dB LE/p 120 dB Lp

(baleen whales including
humpback, blue, sei, fin,
brydes, etc)

Mid-frequency cetaceans 150 – 160,000 198 dB LE/p, 24h 178 dB LE/p 120 dB Lp
(dolphins, toothed whales,
beaked whales, bottlenose
whales)

High-frequency cetaceans 275 – 160,000 173 dB LE/p, 24h 153 dB LE/p 120 dB Lp
(true porpoises, river
dolphins, cephalorhynchid,
etc.)

Notes:
1. Represents the generalised hearing range for the entire group as a composite (i.e. all species within the
group), where individual species hearing ranges are typically not as broad.
2. LE/p, 24h is the weighted cumulative sound exposure level ( L E/p) and has a reference value of
1µPa2s. The recommended accumulated period is 24 hrs. The weighted cumulative sound exposure
level thresholds could be exceeded in a multitude of ways (i.e., varying exposure levels and durations,
duty cycle).
3. Lp – Continuous (non-impulsive) noises are quantified as Sound Pressure Level (SPL, or Lp) using
units of dB re 1 µPa.

Sea Turtles, Fish and Other Fauna

Table 9-19 provides a summary of sound frequencies understood to be utilised by
marine fauna and response thresholds, where known. All data, except where noted, is

8 Underwater noise can generally be considered as two types:

• impulsive noise – typically discrete, short duration noises punctuated by periods of low/no noise,
characterised by high peak sound pressure levels with relatively rapid rise and decay times, and
• non-impulsive – noises that do not have rapid rise and decay times, typically of longer duration.

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referenced from the most recent and comprehensive scientific literature survey on
marine noise from oil and gas activities and impacts on marine fauna, compiled by the
Centre for Marine Science and Technology (CMST), Curtin University, Perth (Kent, C.
et al., 2016).

Table 9-19: Sound Frequencies Utilised by Marine Fauna and Known Response Levels
Species Frequency Range Response levels

Fish Hearing range: 100 Hz – 1,000 Hz (with Recoverable injury: 170 dB Lp for 48 hour
peak hearing from 100 Hz – 400 Hz) exposure (Popper et al. (2014).
< 1,000 Hz (whale sharks) TSS: 158 dB Lp for 12 hour exposure
Popper et al. (2014)
Avoidance: > 155-165 dB re 1μPa2.s
Physical damage: 210-211 dB re 1μPa2.s

Turtles Vocalisation (in air) 300 Hz – 4000 Hz Avoidance: > 155 dB re 1μPa2.s at 1m
Best hearing sensitivity: 100 Hz – 700 Hz Erratic swimming: > 164 dB re 1μPa2.s at 1m

Sharks and rays were grouped with fish (Table 9-19) for this assessment of impacts.
No suitable published guidelines were identified for sea snakes. Sea snakes were
grouped with fish (Table 9-19) for the purposes of this assessment.
While there are reputable published studies indicating the potential for underwater
noise to impact upon invertebrates, no suitable published guidelines were identified for
the specific receiving environment. Invertebrates have been considered in the
assessment of risks and impacts from underwater noise, although no threshold values
have been applied.
Modelling Results vs Threshold Levels
Prelude FLNG activities have the potential for localised and temporary noise impacts
on marine fauna, including fish, marine turtles and cetaceans. Based on the thresholds
outlined above and the hearing bands for different fauna, underwater noise levels
would:
• fall below the relevant cumulative permanent hearing damage criteria for all marine
fauna except high frequency cetaceans, at all locations.
• fall below the permanent hearing damage criteria for high frequency cetaceans (24-hour
cumulative exposure period) within tens of metres of the facility.
• fall below the relevant temporary hearing threshold shift criteria for fish (12-hour
exposure period) beyond 60 metres from the facility.
• fall below the relevant temporary hearing threshold shift criteria for cetaceans beyond
150 metres from the facility during offloading operations.
• fall below the relevant behavioural disturbance criteria for cetaceans at ranges beyond 9
km during offtake operations (cavitation noise) and 1.3 km during normal production
operations (plant noise).

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9.5.2 Description and Evaluation of Impacts

Physical Environment
There are no impacts on the physical environment protected under the EPBC Act such
as air or water quality. Noise impacts are limited to the biological environment as
discussed below.
Biological Environment
Ecosystems, Communities and Habitats
Benthic Communities
Underwater noise generated by operational platforms does not appear to have any
detrimental effect on benthic communities. Inspection of fixed platforms worldwide
shows these structures serve as artificial reefs and develop relatively diverse benthic
communities (Lindquist et al. 2005). Benthic habitat surveys in the Operational Area
indicate the presence of diverse but not abundant or sensitive benthic communities.
Given the frequency spectrum and intensity of noise generated during production
operations, no impacts to benthic communities because of underwater noise are
expected to occur.
Islands, shoals, banks and near the Operational Area may potentially be exposed to
increased underwater noise levels as a result of vessels using DP. These host
relatively diverse fauna communities, such as demersal fish and marine turtles (see
Threatened Species and Ecological Communities below for further discussion).
However, given the distance of these islands shoals and banks from the noise sources
in the Operational Area and the consequent reduction in noise intensity, the received
noise levels will be significantly lower than the source levels. The nearest island to the
Prelude FLNG vessel location is Browse Island, which lies approximately 39 km to the
south. The nearest shoal, Echuca Shoal, is 61 km south. At these distances noise
emissions from the Prelude operations would have fallen to within background noise
levels (see Table 9-16), hence there are no credible potential impacts to island
communities (Refer to Threatened Species and Ecological Communities below for
further discussion of noise impacts on marine turtles).
Pelagic Communities
Pelagic communities in the Operational Area include planktonic communities and
pelagic fish and invertebrates. The effects of noise on free swimming pelagic fish are
assessed below with Threatened Species and Ecological Communities and are not
addressed further in this section.
Planktonic communities comprise a diverse range of taxa, which will differ in their
potential to be impacted by underwater noise. Many species of pelagic and demersal
fish have a planktonic larval stage.
Modelling studies by the CSIRO indicate that planktonic communities are highly
dynamic and have the potential to recover rapidly following disturbance (Richardson et
al. 2017). Experiments have shown mixed results of larval stages to underwater noise.
For example, experiments on several species of fish larvae and lobster larvae did not
detect significant effects as a result of high intensity impulsive noise (Bolle et al. 2012;
Day et al. 2016; Payne et al. 2009).
Impacts to planktonic larvae have not been reliably demonstrated under conditions
analogous to those that will be encountered during Prelude operations, being orders of
magnitude less than that of experimental designs referenced above. The more

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intensive noise sources are of limited duration (e.g. vessels using DP), which limits the
exposure of planktonic organisms. As such, the residual impact consequence to
planktonic communities are considered to be Slight (Magnitude -1, Sensitivity – L).
The Operational Area is not expected to host highly abundant or diverse assemblages
of fish, sharks or rays. The noise modelling indicates that no exceedance of the
permanent injury threshold for any category of fish would occur in the Operational area
and underwater noise levels would fall below the relevant temporary hearing threshold
shift criteria for fish (12 hr exposure period) within 60 m from the facility. The
approximate received level threshold for behavioural disturbance in fish is variable but
indicated to be greater than 90dB re 1μPa above hearing thresholds (Popper et al.
2003, Scholik and Yan 2002a, 2002b, Xodus 2009, Hastings et al. 1996; cited in
Woodside Energy Limited 2011). Therefore, the highest impact on masking
vocalisation and changes to behaviour will occur within tens and hundreds of metres
from the facility for pelagic fish and sharks and rays.
Given the highly mobile nature of fish, sharks and rays and their continual sightings in
the Operational Area around the hull, it is concluded that continuous noise sources
from the FLNG in its production only and simultaneous production and offloading
modes of operation will have at most a slight residual impact consequence (Magnitude
-1, Sensitivity – L) on these resident and transient populations.
Key Ecological Features
The nearest KEF to the Operational Area are the Continental Slope Demersal Fish
Communities, covering a vast area of approximately 33,182 km2, located approximately
14 km in its closest point to Prelude. These are a high diversity of demersal fish
assemblages on the Australian continental slope featuring more than 500 fish species,
76 of which being endemic, which makes it the most diverse slope bioregion in the
whole of Australia.
The noise levels at the closest point of this KEF will be between 120 and 110 dB re:
1uPa in the 10 Hz to 2 KHz band. At these distances there is no potential for
permanent, temporary or behavioural impact to fish with moderate potential for
masking fish choruses only. Potential impacts to the demersal fish communities are
therefore considered not to credible. Other KEFs are too distant from the Operational
Area to be credibly impacted by underwater noise.
Threatened and Migratory Species
Marine Mammals
Most cetacean species use sound to communicate (e.g. humpback whale calls) or
perceive their environment (e.g. echolocation of prey). This reliance on underwater
noise, and their high conservation value, makes cetaceans of concern when assessing
potential impacts from underwater noise. Low frequency cetaceans are expected to be
most vulnerable to underwater noise from Prelude Operations (cavitation and plant
noise) due to the frequency spectra of these noise sources overlapping the functional
hearing range of these species (approximately 7 Hz to 30 kHz). Several low frequency
cetaceans (blue, humpback, sei, fin and Bryde’s whales) were identified as potentially
occurring within the Operational Area (Section 7.2.3). Noise monitoring in the Timor
Sea for the Barossa development indicated pygmy blue and Bryde’s whales are the
most likely to occur (McPherson et al. 2016). Detection of low-frequency cetaceans
calls were not constant, but occurred sporadically, often in groups or sets of calls.
Mid frequency cetaceans are also vulnerable to underwater noise, although their
hearing range means they are more vulnerable to noise frequencies overlapping their

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functional hearing range (approximately 150 Hz to 160 kHz). Mid frequency cetaceans
include most toothed whales, dolphins and porpoises and a number of species of mid
frequency cetaceans were identified as potentially occurring within the Operational
Area and adjacent ZPI (Section 7.2.3). Noise monitoring in the Timor Sea indicates
mid-frequency cetaceans are present year-round (McPherson et al. 2016).
Given that modelling indicates underwater noise levels fall below the relevant
cumulative permanent hearing damage criteria for low and mid frequency cetaceans at
all locations within the Operational Area and fall below the relevant TTS criteria for
cetaceans beyond 150 m from the facility during offloading operations it is considered
that the potential for significant impacts to cetaceans within the Operational area is not
credible. Given also that noise levels from Prelude operations fall below the relevant
behavioural disturbance criteria for cetaceans at ranges beyond 9 km during offtake
operations (cavitation noise) and 1.3 km during normal production operations (plant
noise), the overall impact to marine mammals is considered to be Slight (Magnitude -1,
Sensitivity -M).
Other sources of noise, associated with short term operations, such as operational
flaring or helicopter operations, will be short in duration and largely reflected off the
seawater air barrier to be causing any greater impact on cetaceans than a temporary
behavioural response. A similar level of impact is expected from use of side scan
sonars during subsea infrastructure IMR activities, which due to being high-frequency
sounds are known to be outside the hearing thresholds of cetaceans (see data
summary in Table 9-17). Impacts from side scan sonars are therefore expected to
cause no greater than slight impacts to marine mammals.
Marine vessel underwater noise emissions are of frequencies detectable by marine
mammals however the sound levels at the source itself will be of magnitude that could
cause at worst a TSS for an animal happening to be in a very close proximity (within
tens of meters of the vessel). The most likely impact consequence at these levels is a
behavioural response such as avoidance. For a PTS impact to occur, the mammal
should be swimming within metres of the vessel for more than 24 hours, which is a
non-credible scenario. It is therefore concluded that noise emissions from marine
vessels could potentially cause only a slight residual impact on marine mammals
(Magnitude -1, Sensitivity - M).
Marine Reptiles
Marine reptiles such as turtles and sea snakes are not known to be particularly
sensitive to underwater noise. Research on marine turtles suggests that functional
hearing is concentrated at frequencies between 100 and 600 Hz (which is a subset of
the low frequency cetacean range). Several turtle species were identified as likely to
occur within the Operational Area (Section 7.2.3), although no critical habitat or BIAs
overlap the Operational Area. The closest critical marine turtle habitats include green
turtle nesting habitat some 17 km from Prelude FLNG and foraging habitat some 43 km
from Prelude. Noise levels at the 17 km distance from Prelude are approximately 110
dB re 1uPa during offloading operations only (24 to 48 hrs per week on average) and
90dB re 1uPa for the rest of the time (background plant operations noise) and impacts
to marine turtles at this distance are expected to be slight (refer to Table 9-19). All
other marine turtle habitats are more than 100 km away from the Operational Area,
hence there are no potential for impacts to those. Impacts from marine vessel noise
emissions are also expected to be Slight (Magnitude -1, Sensitivity - M) due to the
large separation distance between the Operational Area and the closest marine turtle
habitats and the continuous nature and sound levels of marine vessel noise at source.

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Impacts on sea snakes from all sources discussed above are similarly expected to be
slight with reference to response levels for fish in Table 9-19.

Whale Sharks
Whale sharks may traverse the Operational Area and broadly the ZPI with a BIA for
foraging whale sharks located 33 km from the Operational Area. However, it is
expected that whale shark presence within the Operational Area would not be in
significant numbers and would be transitory and of short duration. This is consistent
with tagging studies of whale shark movements which show continual movement of
whale sharks in deeper, open offshore waters (Meekan & Radford 2010). Whale sharks
are also not considered to be particularly vulnerable to noise related impacts (refer to
response levels for fish in Table 9-19).
Overall, the worst-case residual impact consequence to biological communities is
assessed as Slight (Magnitude -1, Sensitivity - M).
Socio-Economic Environment
No reasonably foreseeable adverse impacts from Prelude noise emissions, including
consideration of supply vessel and helicopter operations and impacts on commercial
fishing stocks (discussed in Biological Environment), have been identified on the socio-
economic environment.

9.5.3 Impact Assessment Summary

Table 9-20 lists the highest residual impact consequence ranking of the relevant
environmental receptor groups.

Table 9-20: Noise Evaluation of Residual Impacts

Consequence
Sensitivity
Magnitude

Residual

Environmental Receptor
Impact

Evaluation – Planned Impacts

Physical Environment N/A N/A N/A
Biological Environment -1 M Slight
Socio-Economic Environment N/A N/A N/A

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9.5.4 ALARP Assessment and Environmental Performance Standards

Table 9-21: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Performance Measurement

Controls Standard (EPS) Criteria
Elimination N/A N/A No additional or alternative control measures N/A N/A N/A
have been identified for this risk for the
Prelude activities.
Substitution N/A N/A No additional or alternative control measures N/A N/A N/A
have been identified for this risk for the
Prelude activities.
Engineering N/A N/A No additional or alternative control measures N/A N/A N/A
have been identified for this risk for the
Prelude activities.
Administrative Marine support vessel Yes The EPBC Regulations 2000 – Part 8 3.1 Vessels will comply with EPBC Incident report form
and Procedural interactions with threatened and Division 8.1 (Regulations 8.05 and 8.06) and Regulations 2000 Part 8, Division used to record
Controls migratory species to follow the of the Australian National Guidelines for Whale 8.1 Interacting with cetaceans breaches of
EPBC Regulations 2000 – Part 8 and Dolphin Watching 2017 (DoEE 2017) are and the Australian National requirements outlined
Division 8.1 (Regulations 8.05 recognised as the industry standard for Guidelines for Whale and Dolphin in the EBPC
and 8.06) and the Australian minimising disturbance due to physical Watching. Regulations 2000 and
National Guidelines for Whale presence and noise to whales and dolphins Australian National
and Dolphin Watching 2017 and will be applied to other species as Guidelines for Whale
(DoEE 2017). relevant, .i.e. turtles and whale sharks. and Dolphin
Watching.

Administrative Infield environmental noise No Marine noise monitoring alone will not N/A N/A N/A
and Procedural monitoring prevent impact to marine fauna, but will
Controls provide the noise signature of Prelude
operations in time.

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9.5.5 Acceptability of Impacts

Table 9-22: Acceptability of Impacts - Noise

Receptor Receptor Acceptable Level of Are the Acceptability

Category Sub- Impact Impacts of an Assessment
category Acceptable
Level?
Physical N/A N/A N/A N/A
Environment
Biological Benthic Benthic habitat surveys
No significant direct Yes in the Operational Area
Environment Communities impacts to bare did not indicate the
sediment benthic presence of particularly
habitats outside of the diverse or sensitive
Operational Area as a benthic communities.
result of the petroleum Benthic habitats
activities which associated with high
adversely effects value sensitive benthic
biological diversity or communities e.g.
ecological integrity. named reefs, banks
and shoals are too
No direct impacts to distant to be affected
high-value sensitive by noise (i.e. Browse
benthic communities Island is approximately
(corals, macroalgae, 39 km from the
seagrasses and Operational Area and
mangroves) associated Echuca Shoal is
with named reefs, banks approximately 61 km
and shoals. from the Operational
Area). Given the
frequency spectrum
and intensity of noise
generated during
production operations
and the large
separation distances to
the nearest high value
sensitive benthic
communities, no
impacts to benthic
communities as a result
of underwater noise are
expected to occur.

Pelagic No significant adverse Yes No exceedance of the

Communities effect on pelagic permanent injury
including communities, threshold for any
planktonic populations, habitats or category of fish is
communities spatial distribution of a predicted to occur in
and pelagic species. the Operational area
fauna and beyond and
ambient underwater
noise levels would fall
below the relevant
temporary hearing
threshold shift criteria
for fish (12 hr exposure
period) beyond 60
metres from the facility.
Masking vocalisation
and changes to

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Receptor Receptor Acceptable Level of Are the Acceptability

Category Sub- Impact Impacts of an Assessment
category Acceptable
Level?
behaviour could occur
only within tens and
hundreds of metres
from the facility.
Impacts to widely
distributed planktonic
communities in the
Operational Area have
been assessed as 1-
Slight.
KEFs No impacts to Yes The nearest KEF is the
environmental values of Continental Slope
KEFs Demersal Fish
Communities, located
approximately 14 km in
their closest point to
Prelude. The noise
levels at this point
indicate no potential for
permanent, temporary
or behavioural impact
to fish with moderate
potential for masking
fish choruses only.
Other KEFs are too
distant from the
Operational Area to be
credibly impacted by
underwater noise.

Threatened No significant impacts to Yes Noise levels emitted

and Migratory listed Threatened from the FLNG and
Species (Endangered and support vessels during
Vulnerable) or Migratory normal production and
MNES fauna populations offtake operations have
as a result of noise been assessed as
emissions. potentially able to
Management of aspects cause a slight impact
of the project must be on threatened or
aligned to conservation migratory marine
advice, recovery plans fauna. Side scan sonar
and threat abatement sources are of
plans. frequencies outside of
hearing range of
cetaceans. Turtle
nesting and inter-
nesting habitats are at
least 20 km from the
FLNG vessel and
known whale migration
routes and
congregation areas are
hundreds of kilometres
distant from Prelude.
Noise emissions would
therefore have no
significant impact on

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Receptor Receptor Acceptable Level of Are the Acceptability

Category Sub- Impact Impacts of an Assessment
category Acceptable
Level?
threatened and
migratory species.
Socio- N/A N/A N/A
economic
and Cultural
Environment

The assessment of impacts from noise determined the worst-case residual ranking of
Slight or lower (Table 9-22). As outlined above, the acceptability of the impacts from
noise associated with the Prelude operations have been considered in the context of:
Principles of ESD
Impacts from noise emissions are consistent with the principles of ESD based on the
following points:
• The noise emissions aspect does not degrade the biological diversity or ecological
integrity of the Commonwealth Marine Area and significant impacts to MNES are not
anticipated to occur.
• The precautionary principle has been applied, and since the last revision of this EP the
most recent and comprehensive scientific literature compilation (Kent et al, 2016) and
the most recent international guidelines on noise impacts (Popper et al. 2014) have
been reviewed and referenced to ensure latest research and knowledge are taken into
account in the evaluation of environmental impacts.
Relevant Requirements
Management of impacts from noise emissions is consistent with relevant legislative
requirements, including:
• Assessment of noise impacts is guided by the latest scientific research in defining
impact thresholds (Popper et al. 2014) and includes a purpose conducted noise
emissions modelling for the main modes of FLNG operation.
• Management of noise impacts is consistent with policies, strategies, guidelines and
conservation advice (refer to Table 9-23).
• Marine support vessel interactions with threatened and migratory species to follow the
EPBC Regulations 2000 – Part 8 Division 8.1 (Regulations 8.05 and 8.06) and the
Australian National Guidelines for Whale and Dolphin Watching 2017 (DoEE 2017), i.e.
o Marine support vessels will not deliberately approach closer than 50 m to a
dolphin, turtle or whale shark; 100 m for an adult whale; 300m for a whale calf;
and 150m for a dolphin calf.
o If the whale, dolphin, turtle or whale shark shows signs of being distressed,
marine support vessels will immediately withdraw from the caution zone at a
constant speed of less than 6 knots.
Matters of National Environmental Significance
Threatened and Migratory Species
The evaluation of noise impacts indicates significant impacts to threatened and
migratory species will not credibly result from noise emissions from production,

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offloading, materials and personnel transfer and subsea infrastructure operations and
maintenance aspects of the Prelude petroleum activities.
Alignment of Prelude petroleum activities with management plans, recovery plans and
conservation advice for threatened and migratory fauna is provided in Table 9-23.
Commonwealth Marine Environment
Impacts from the noise aspect of the Prelude field on the Commonwealth Marine
Environment will not exceed any of the significant impact criteria provided in Table
9-22.

Table 9-23: Summary of Alignment of the Impacts from the Noise Aspect of the Prelude
petroleum activities with Relevant Requirements for EPBC Threatened Fauna

Matters of MNES Acceptability Demonstration of Alignment as Relevant to the

National Considerations (EPBC Project
Environmental Management Plans/Recovery
Significance Plans/Conservation Advices)
Threatened and Conservation advice on sei whale Vessel interactions with threatened and migratory
Migratory (Balaenoptera borealis) (DoE species to follow the of EPBC Regulations 2000 – Part 8
Species - 2015c) Division 8.1 (Regulations 8.05 and 8.06) and the
Marine Australian National Guidelines for Whale and Dolphin
Conservation advice on fin whale
Mammals (Balaenoptera physalus) (DoE Watching 2017 (DoEE 2017).
2015d) A noise assessment consistent with the
recommendations of the Technical guidance for
Conservation management plan assessing the effects of anthropogenic sound on marine
for the blue whale: A recovery mammal hearing (NOAA 2018) was undertaken.
plan under the Environment
Protection and Biodiversity
Conservation Act 1999 2015–
2025 (Commonwealth of Australia
2015a)
Conservation advice on
humpback whale (Megaptera
novaeangliae) (DoE 2015b)
Threatened and Significant impact guidelines for The evaluation of environmental impacts indicates that
Migratory Critically Endangered, impacts from noise emissions on threatened or
Species - Endangered, Vulnerable and migratory marine reptiles are slight and would not
Marine Reptiles Migratory species (Table 8-1). constitute a significant impact. As such, the Prelude field
does not exceed any of the significant impact criteria for
Threatened and Migratory marine reptile species
provided in Table 8-1.
Recovery Plan for Marine Turtles Acute and chronic noise pollution has been identified as
in Australia 2017–2027 a threat in the Recovery Plan for Marine Turtles (DoEE
(Commonwealth of Australia 2017), however there are no specific actions in the Plan
2017) in relation to noise pollution, except a recognised need
to conduct additional research on impacts of noise on
turtles.
A noise assessment consistent with the
recommendations of the Sound exposure guidelines for
fishes and sea turtle (Popper et al. 2014) was
undertaken.
Other Species Conservation advice on whale A noise assessment consistent with the
– Sharks and shark (Rhincodon typus) (DoE recommendations of the Sound exposure guidelines for
Rays 2015e) fishes and sea turtle (Popper et al. 2014) was
undertaken. This considered the potential impacts of
underwater noise on whale sharks.

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Matters of MNES Acceptability Demonstration of Alignment as Relevant to the

National Considerations (EPBC Project
Environmental Management Plans/Recovery
Significance Plans/Conservation Advices)
Commonwealth Significant Impact Guidelines for The evaluation of environmental impacts indicates that
Marine the Commonwealth marine the noise emissions aspect of Prelude operations will
Environment environment (Table 8-1) not exceed the Commonwealth marine environment
significant impact criteria provided in Table 8-1.

External Context
There have been no objections or claims raised by Relevant Persons to date on the
noise aspect. Shell’s ongoing consultation program will consider statements and claims
made by stakeholders when undertaking further assessment of impacts and risks.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements.
Acceptability Summary
The assessment of impacts and risks from noise determined the residual impact
rankings were Slight (Table 9-21). As outlined above, the acceptability of impacts from
noise have been considered in the context of:
• The established acceptability criteria for the noise aspect
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
Shell considers residual impacts of noise of Slight or lower to be acceptable if they
meet legislative and Shell requirements. The discussion above demonstrates that
these requirements have been met in relation to noise.
Based on the points discussed above, Shell considers the impacts from noise
associated with the Prelude project to be acceptable.

9.5.6 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

No injury or mortality to listed Threatened Fauna observations and incident reports

or Migratory MNES species as a result of demonstrate no injury or mortality of
noise emissions. listed Threatened or Migratory species
as a result of noise emissions within the
Operational Area.

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9.6 Disturbance to Seabed

9.6.1 Aspect Context

During certain IMR related activities, localised seabed disturbance may occur. Such
disturbance may result from activities including, but not limited to:
• Replacement of subsea equipment/infrastructure
• Placement of ROV tool baskets and DP transponders
• IMR activities such as free-span rectification, scour protection, groutbag/mattress
installation, pipeline secondary stabilisation and/or water jetting/sand displacement to
allow access to infrastructure.
The physical presence of permanent infrastructure already installed is addressed in
Section 9.4 is not considered further in this section.

9.6.2 Description and Evaluation of Impacts

Physical Environment
Subsea facilities have a physical impact on the seafloor and the associated benthic
communities. The significance of the impact depends on the sensitivity of the seafloor
habitat being affected. The disturbance footprint associated with subsea infrastructure
will be highly localised.
The disturbance from IMR related activities such as rectification and/or stabilisation is
expected to be highly localised to discrete areas. The footprint on the seabed of grout
bags on the seabed is typically confined to a small area directly below the flowline. The
footprint of a grout bag is a consequence of the size of the bag. Bag size selection
typically depends on the size of the span that requires rectification; larger spans
typically require larger bags; most have a footprint < 100 m2. The footprint of a mattress
depends on the size of the mattress being used; typical mattresses cover
approximately 100 m2. Mattress size selection is dependent on the scale of the span or
stabilisation required. While the need for grout bags or mattresses (if any) is currently
unknown, operational experience indicates they will not be required in large numbers
given typically the short flowline length/ span requiring support.
Water Quality
The potential for activities to increase turbidity is based on the possibility of sediment
resuspension as a result of water jetting, ROV thruster wash, flushing grout lines or via
placement of equipment, infrastructure, rock, mattresses or grout bags for example.
ROV thrusters can resuspend unconsolidated material, including sediments, and
restrict visibility and operation of the ROV in the immediately vicinity which is counter-
productive for the pilot. For this reason, ROV operators aim to minimise thruster wash
by reducing use of thrusters adjacent to unconsolidated material and operating at a
height above the sea floor that reduces resuspension.
Any impacts to water quality (turbidity) from seabed disturbance are expected to be
restricted to highly localised and short-term sediment plumes. Sediment plumes may
result in a slight and temporary decrease in water quality due to increase in suspended
sediments. These temporary impacts to water quality are expected to have no credible
environmental damage or effects.
Sediment Quality

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Impacts to sediment quality from seabed disturbance are considered to have no

environmental damage or effects. Significant changes to physical properties, such as
particle size distribution and geological origin, are not expected to occur due to the
small-scale, localised and infrequent nature of the associated activities.
Biological Environment
The seabed within the Operational Area has low density of epibenthic communities due
to the low variance of sea floor topography and absence of hard substrates limiting
habitat for epibenthic organisms (Baker et al. 2008; Heyward & Smith 1997). This has
been determined for the Prelude location from benthic surveys, side scan sonar, 3D
seismic survey and geotechnical data collected across the permit area (Shell 2009).
The soft seabed comprises of very soft siliceous carbonate silts, which has been
shown to support a high diversity but low abundance community of infaunal
assemblages. The likely impacts to the benthic communities from seabed disturbance
include smothering and temporary disturbance but soft sedimentary communities have
been shown to respond rapidly to disturbance and impacts are thus expected to be
slight and short-lived (Shell 2009).
The habitats associated with these communities are broadly distributed in the wider
region and are not considered to be unique or highly sensitive. The installation of
additional infrastructure associated with the petroleum activities (including stabilisation
or span rectification using grout bags/mattresses) may result in the disruption of a
relatively small area of soft sediment habitats, which will then become hard substrate
habitats due to the presence of subsea infrastructure.
Given the widespread extent of similar habitat, the low sensitivity of the benthic habitat
within the Operational Area, and the high likelihood that temporarily affected areas will
recover in a short timeframe, the environmental effects are considered to be of minimal
ecological significance. Thus, the overall residual impact consequence level is ranked
as Slight (Magnitude -1, Sensitivity – L).

9.6.3 Impact Assessment Summary

Table 9-24: Benthic Disturbance Evaluation of Residual Impacts
Consequence
Sensitivity
Magnitude

Residual

Environmental Receptor
Impact

Evaluation – Planned Impacts

Physical Environment 0 L No Impact
Biological Environment -1 L Slight
Socio-Economic Environment N/A N/A N/A

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9.6.4 ALARP Assessment and Environmental Performance Standards

Table 9-25: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)
Elimination Eliminate IMR activities No Subsea IMR activities (that result in seabed N/A N/A N/A
disturbance) are essential for maintaining the
integrity of the subsea hydrocarbon system and
cannot be avoided. The alternative of doing nothing
would potentially compromise the integrity of the
system, with increased technical risks and
production failures, resulting in significant financial
costs and potentially leading to increased risks of
loss of containment, resulting in environmental
costs.
Substitution N/A N/A N/A N/A N/A

Engineering During IMR activities, Yes The costs are not disproportionate to the negligible 4.1 During IMR activities, As-laid surveys are
infrastructure is laid on the environmental benefit potentially gained through infrastructure is laid on the performed following
seabed according to plan avoiding the small and infrequent seabed seabed within the installation activities to
disturbances associated with IMR activities. Operational Area confirm the facilities have
been laid within the
Operational Area
Administrative Anchoring in the Yes No alternative control measures have been 4.2 No support vessel Records verify no breaches
and Procedural Operational Area for identified. anchoring in the Operational of anchoring procedures in
Controls support vessels is Area except in emergency the Operational Area.
prohibited except in situations or under issuance
emergency situations or of a specific permit by Shell
under issuance of a
specific permit by Shell

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9.6.5 Acceptability of Impact

Table 9-26: Acceptability of Impact – Disturbance to Seabed

Receptor Receptor Sub- Acceptable Level Are the Acceptability Assessment

Category category of Impact Impacts of
an
Acceptable
Level?
Physical N/A N/A N/A N/A
Environment
Biological Benthic No significant direct Yes No significant impacts are
Environment Communities – impacts to bare expected, given the Operational
Bare Sediment sediment benthic Area represents a small portion
habitats outside of the of a large regional bare sediment
Operational Area as a benthic environment. Habitats
result of the petroleum associated with these
activities communities are broadly
distributed in the wider region
Commonwealth No significant impacts Yes and are not considered to be
Marine to the Commonwealth unique or highly sensitive. Any
Environment Marine Environment seabed disturbance within the
Operational Area will be small in
scale, infrequent and represent a
small fraction of the overall
Operational Area and therefore
any impacts are not expected to
affect ecosystem function or
connectivity of communities.
Socio- N/A N/A N/A N/A
economic and
Cultural
Environment

The assessment of impacts from seabed disturbance determined the residual ranking
of Slight or lower. As outlined above, the acceptability of the impacts associated with
the petroleum activity have been considered in the following context.
Principles of ESD
The impacts from seabed disturbance are consistent with the principles of ESD based
on the following points:
• Seabed disturbance on such a small scale will not degrade the biological diversity or
ecological integrity of the Commonwealth Marine Environment and therefore significant
impacts to MNES will not occur.
• The health, diversity and productivity of the marine environment will be maintained for
future generations.
• The precautionary principle has been applied, and studies undertaken where knowledge
gaps were identified (Refer to Section 7.2.1). This knowledge has been applied during
the evaluation of environmental impacts.
Relevant Requirements
Management of the impacts from seabed disturbance are consistent with relevant
legislative requirements, including:

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• Management of impacts are consistent with guidelines for the protection of MNES
(Table 8-1).
Matters of National Environmental Significance
Commonwealth Marine Environment
The impacts from the seabed disturbance aspect of the Prelude field on the
Commonwealth Marine Environment will not exceed any of the significant impact
criteria provided in Table 9-27.

Table 9-27: Summary of Alignment of the Impacts from the Seabed Disturbance Aspect of
the Prelude Petroleum Activities with Relevant Requirements for MNES

Matters of MNES Acceptability Demonstration of Alignment as

National Considerations (EPBC Relevant to the Project
Environmental Management Plans/Recovery
Significance Plans/Conservation Advices)
Commonwealth Significant Impact Guidelines The impact assessment indicates that
Marine for the Commonwealth Marine the seabed disturbance aspect will not
Environment Environment (Table 8-1) exceed the Commonwealth Marine
Environment significant impact criteria
provided in Table 8-1.

External Context
There have been no objections or claims raised by Relevant Persons to date around
the seabed disturbance aspect. Shell’s ongoing consultation program will consider
statements and claims made by stakeholders when undertaking further assessment of
impacts.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements.
Acceptability Summary
The assessment of impacts and risks from seabed disturbance determined the residual
impact rankings were Slight or lower Table 9-24). As outlined above, the acceptability
of the impacts have been considered in the context of:
• The established acceptability criteria for the seabed disturbance aspect
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).

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Shell considers residual impacts of Slight or lower to be acceptable if they meet

legislative and Shell requirements. The discussion above demonstrates that these
requirements have been met in relation to the seabed disturbance aspect.
Based on the points discussed above, Shell considers the impacts from seabed
disturbance associated with the Prelude petroleum activities to be ALARP and
acceptable.

9.6.6 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

No direct disturbance to benthic habitats Records demonstrate there has been no

outside of the Operational Area as a significant direct disturbance to bare
result of inspection, maintenance and sediment benthic habitats outside of the
repair activities associated with Prelude Operational Area as a result of the
operations. petroleum activities, that is activities
associated with inspection, maintenance
and repair.

9.7 Vessel Movements

9.7.1 Aspect Context

Marine vessels moving in the Operational Area may present a hazard to threatened
and migratory fauna, such as whales, turtles and whale sharks (though the abundance
of such fauna in and around the Operational Area has been observed to be low).
Vessel movements can result in collisions between the vessel and marine fauna,
potentially resulting in injury or death. Factors affecting the likelihood and severity of
impacts from collisions include vessel type, vessel speed, water depth and the
behaviours of animals present (Commonwealth of Australia 2017).

9.7.2 Description and Evaluation of Risks

The risks of vessel collisions with marine fauna, particularly threatened and migratory
species (i.e. MNES), described below are consistent with the acceptable levels of
impacts defined in Section 8.0. Shell’s environmental management of the vessel
movements aspect of the petroleum activities is aligned with conservation advice,
recovery plans and threat abatement plans published by the DAWE; refer to discussion
of MNES in the discussion of acceptability below.
Potential risks associated with vessel movements within the operational area are
discussed below. As outlined in Section 9.2.3, the assessment considers only the
residual risks following the application of controls.
Biological Environment
Threatened and Migratory Species
The Operational Area is not adjacent to or near any known important habitats for
threatened or migratory species or the humpback whale migration routes. There are no
BIAs or critical habitats within the Operational Area with the closest such areas located
23 km away for turtles, 33 km away for whale sharks and 78 km for marine mammals.

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Therefore, the abundance of threatened or migratory species in the Operational Area is

expected to be low and their presence transient.
Turtles: The Operational Area does not represent important habitat for marine turtles
given the absence of potential nesting. Much of the project area is in water depths
exceeding 90 m, which is deeper than typical foraging dives by marine turtles (e.g.
Hays et al. 2001; Polovina et al. 2003). As such, the presence of marine turtles within
the Operational Area is likely to be restricted to individual turtles transiting the area. As
with cetaceans, the risk of collisions between turtles and vessels increases with vessel
speed (Hazel et al. 2007). The typical response from turtles on the surface to the
presence of vessels is to dive (a potential “startle” response), which decreases the risk
of collisions (Hazel et al. 2007). Given the low speeds of vessels in the operational
area, along with the expected low numbers of turtles in the area, the likelihood of
collisions between vessels and turtles is assessed as remote.
Whale sharks: These are at risk from vessel strikes when feeding at the surface.
Whale sharks have been observed traversing the Operational Area however, it is
expected that whale shark presence would not comprise of significant numbers given
there is no main aggregation area within the vicinity, and their presence would be
transitory. This is consistent with tagging studies of whale shark movements which
show continual movement of whale sharks in deeper, open offshore waters (Meekan &
Radford 2010). There are no constraints preventing whale sharks from moving away
from vessels (e.g. shallow water or shorelines).
Whales and Dolphins: Whales are particularly vulnerable to collisions with vessels
due to their large size and the relatively high proportion of time spent at or near the sea
surface. The likelihood and consequence of vessel collisions with whales are
influenced by vessel speed; the greater the speed at impact, the greater the risk of
mortality (Jensen and Silber 2004; Laist et al. 2001). Vanderlaan and Taggart (2007)
found that the chance of lethal injury to a large whale as a result of a vessel strike
increases from about 20% at 8.6 knots to 80% at 15 knots. According to the data of
Vanderlaan and Taggart (2007), it is estimated that the risk is less than 10% at a speed
of 4 knots. Although dolphins are at much lower risk from collision due their small size,
manoeuvrability and echolocation abilities compared to whales, they are still included in
this assessment given they surface to breathe and are known to feed near the surface
at times.
Marine vessels within the Operational Area, carrying out petroleum activities, are likely
to be travelling at speed less than 8 knots; much of the time vessels are holding station
or moving very slowly under Dynamic Positioning (DP) due to operational safety
requirements. Therefore, the likelihood of a vessel collision with threatened or
migratory species is remote (B).
Marine mammals, turtles and sharks are expected to alter course away from the FLNG
as well as stationary or slow-moving product offtake, IMR, supply and support vessels
in the Operational Area. The cruising speed of supply and support vessels is relatively
low and a watch is maintained at all times and any interactions will be managed in line
with the requirements of the Australian National Guidelines for Whale and Dolphin
Watching 2017 (DoEE 2017).
This activity is identical to vessel movements for other offshore activities along the
Western Australian coastline where the incidence of vessel strike is remote. Any
collisions are only likely to affect fauna at an individual scale rather than at a
population or species scale. Therefore, an injury or death of an individual from a
threatened or migratory species from a collision is considered to be of minor impact
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consequence (Magnitude -2, Sensitivity – M) and remote (B) likelihood with a residual
risk assessed as Dark Blue.

9.7.3 Risk Assessment Summary

Table 9-28: Vessel Collision with Marine Life Evaluation of Residual Risks

Consequence

Residual Risk
Likelihood
Environmental Receptor

Evaluation – Unplanned Risks

Biological Environment Minor B - Remote Dark Blue

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9.7.4 ALARP Assessment and Environmental Performance Standards

Table 9-29: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Performance Measurement

Controls Standard (EPS) Criteria
Elimination Elimination N/A No appropriate control measures N/A N/A N/A
have been identified to eliminate this
risk from Prelude activities.
Substitution Substitution No The number of vessels used is N/A N/A N/A
already considered minimal. Any
fewer vessels will not meet
operational needs.
Engineering Engineering No No appropriate control measures N/A N/A N/A
have been identified to reduce noise
through engineering means.
Administrative Vessel interactions with Yes The EPBC Regulations 2000 – Part 3.1 Vessels will comply with EPBC Incident report form
and Procedural threatened and migratory 8 Division 8.1 (Regulations 8.05 and Regulations 2000 Part 8, Division 8.1 used to record breaches
Controls species to follow the of 8.06) and the Australian National Interacting with cetaceans and the of requirements outlined
EPBC Regulations 2000 – Guidelines for Whale and Dolphin Australian National Guidelines for Whale in the EBPC
Part 8 Division 8.1 Watching 2017 (DoEE 2017) are and Dolphin Watching. Regulations 2000 and
(Regulations 8.05 and 8.06) recognised as the industry standard Australian National
and the Australian National for minimising disturbance due to Guidelines for Whale
Guidelines for Whale and physical presence and noise to and Dolphin Watching.
Dolphin Watching 2017 whales and dolphins and will be
(DoEE 2017). applied to other species as relevant,
.i.e. turtles and whale sharks.
Administrative Environmental awareness Yes All employees and contractors 5.1 Relevant vessel-based personnel are EP training records
and Procedural training for personnel working on or in connection with aware of requirements to avoid harm to
Controls Prelude with defined responsibilities marine fauna from vessel movements.
to fulfil as part of the EP are required
to attend EP training that is formally
tracked. The EP training covers

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Performance Measurement

Controls Standard (EPS) Criteria
marine fauna interaction (Section
10.3.2).
Administrative Dedicated Marine Fauna No The cost to have dedicated trained N/A N/A N/A
and Procedural Observers (MFOs) on MFOs on vessels represents a
Controls vessels disproportionate cost given the low
likelihood of the event occurring due
to the absence of critical habitats
within the Operational Area.

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9.7.5 Acceptability of Risks

Table 9-30: Acceptability of Risks – Vessel Movements

Receptor Receptor Acceptable Level of Are the Impacts Acceptability

Category Sub- Impact of an Acceptable Assessment
category Level?
Physical N/A N/A N/A N/A
Environment
Biological Threatened No significant impacts Yes Vessel movement risks
Environment and to listed Threatened are of an acceptable
Migratory (Endangered and level, given the
Species Vulnerable) or Migratory Operational Area is not
MNES fauna located in any BIAs or
populations (Refer to habitat critical to the
Table 8-1) survival of a species.
Given the low speeds of
vessels, along with the
expected low
abundance of
threatened and
migratory species within
the Operational Area,
significant impacts to
Threatened and
Migratory Species are
not anticipated.
Socio- N/A N/A N/A N/A
economic
and Cultural
Environment

The assessment of risks from vessel movements determined the residual ranking of
Dark Blue (Table 9-6), deemed as Inherently Acceptable. As outlined above, the
acceptability of risks from vessel movements associated with the petroleum activities
has been considered in the following context.
Principles of ESD
Risks from vessel movement are consistent with the principles of ESD based on the
following points:
• The vessel movements aspect does not degrade the biological diversity or ecological
integrity of the Commonwealth marine area in the Browse Basin. Significant impacts to
MNES will not occur.
• The health, diversity and productivity of the marine environment will be maintained for
future generations.
• The precautionary principle has been applied, and studies undertaken where knowledge
gaps were identified. This knowledge has been applied during the evaluation of
environmental risks.
Relevant Requirements
Management of risks from vessel movements are consistent with relevant legislative
requirements, including:

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• Marine support vessel interactions with threatened and migratory species to follow the
EPBC Regulations 2000 – Part 8 Division 8.1 (Regulations 8.05 and 8.06) and the
Australian National Guidelines for Whale and Dolphin Watching 2017 (DoEE 2017), i.e.
o Marine support vessels will not deliberately approach closer than 50 m to a
dolphin, turtle or whale shark; 100 m for an adult whale; 300m for a whale calf;
and 150m for a dolphin calf.
o If the whale, dolphin, turtle or whale shark shows signs of being distressed, marine
support vessels will immediately withdraw from the caution zone at a constant
speed of less than 6 knots.
• Management of risks are consistent with policies, strategies, guidelines, conservation
advice, and recovery plans for threatened species (refer to Table 9-31 below).
Matters of National Environmental Significance
Threatened and Migratory Species
The evaluation of risks indicates significant impacts to threatened and migratory
species will not credibly result from the vessel movements aspects of the petroleum
activities.
An unplanned collision between project vessels and threatened or migratory fauna is
unlikely to occur and may result in injury to or death of individual animals. This
unplanned event is not considered to have the potential for significant impacts to
threatened or migratory species at the population level.
Alignment with management plans, recovery plans and conservation advice for
threatened and migratory fauna is provided in Table 9-31.
Commonwealth Marine Environment
The impacts and risks from the vessel movements aspect of Prelude operations on the
Commonwealth marine environment will not credibly exceed any of the significant
impact criteria provided in Table 8-1.

Table 9-31: Summary of Alignment of the Risks from the Vessel Movements Aspect of the
Prelude Petroleum Activities with Relevant Requirements for EPBC Threatened Fauna

Matters of MNES Acceptability Demonstration of Alignment as Relevant to the Project

National Considerations (EPBC
Environmental Management
Significance Plans/Recovery
Plans/Conservation
Advices)
Threatened Significant impact The risk assessment indicates that the likelihood of vessel
and Migratory guidelines for Critically collisions with threatened or migratory marine mammals is remote,
Species – Endangered, and the consequence of any such collision would be restricted to
Marine Endangered, Vulnerable an individual animal. As such, the petroleum activities do not
Mammals and Migratory species exceed any of the significant impact criteria for Threatened and
(Table 8-1) Migratory marine species provided in Table 8-1.
National Strategy for Vessel movements will be aligned to ‘Objective 3: Mitigation’ of the
Reducing Vessel Strikes Strategy by:
on Cetaceans and other • Maintaining separation of vessels and whales;
Marine Megafauna
• Maintaining slow vessel speeds; and
(Commonwealth of
Australia 2017a) • Avoidance manoeuvres.
This will be met by marine support vessels adhering to Part 8
(Interacting with cetaceans and whale watching) of the EPBC
Regulations.

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Matters of MNES Acceptability Demonstration of Alignment as Relevant to the Project

National Considerations (EPBC
Environmental Management
Significance Plans/Recovery
Plans/Conservation
Advices)
Note the other objectives of the Strategy relate to actions for
Government agencies.
Conservation advice on The risk of vessel strikes will be managed by marine support
sei whale (Balaenoptera vessels adhering to the EPBC Regulations 2000 – Part 8 Division
borealis) (DoE 2015c) 8.1 (Regulations 8.05 and 8.06) and the Australian National
Guidelines for Whale and Dolphin Watching 2017.
Conservation advice on
fin whale (Balaenoptera
physalus) (DoE 2015d)
Conservation
management plan for the
blue whale: A recovery
plan under the
Environment Protection
and Biodiversity
Conservation Act 1999
2015-2025
(Commonwealth of
Australia 2015)
Conservation advice on
humpback whale
(Megaptera
novaeangliae) (DoE
2015b)
Threatened Significant impact The risk assessment indicates that the likelihood of vessel
and Migratory guidelines for Critically collisions with threatened or migratory marine reptiles is remote,
species - Endangered, and the consequence of any such collision would be restricted to
marine reptiles Endangered, Vulnerable an individual animal. As such, the petroleum activities do not
and Migratory species exceed any of the significant impact criteria for Threatened and
(Table 8-1) Migratory marine species provided in Table 8-1.
Recovery Plan for Marine Marine support vessel collisions with turtles are inherently unlikely
Turtles in Australia 2017- due to the offshore location (and resultant low densities of turtles),
2027 (Commonwealth of slow speeds of vessels and diving startle response of turtles.
Australia 2017b) Furthermore, the risk of a vessel collision with a turtle will be
further reduced via the implementation of the EPBC Regulations
Conservation advice on
leatherback turtle 2000 – Part 8 Division 8.1 (Regulations 8.05 and 8.06) and the
(Dermochelys coriacea) Australian National Guidelines for Whale and Dolphin Watching
(DEWHA 2009a) 2017.

Threatened Significant impact The risk assessment indicates that the likelihood of vessel
and Migratory guidelines for Critically collisions with threatened or migratory sharks and rays is remote,
species - Endangered, and the consequence of any such collision would be restricted to
sharks and Endangered, Vulnerable an individual animal. As such, the petroleum activities do not
rays and Migratory species exceed any of the significant impact criteria for Threatened and
(Table 8-1) Migratory marine species provided in Table 8-1.
Conservation advice on The Operational Area is not recognised as a BIA or habitat critical
whale shark (Rhincodon to the survival of whale sharks. The conservation advice
typus) (DoE 2015e) recommends minimising offshore developments close to marine
features that may aggregate whale sharks and cites Ningaloo Reef
and Christmas Island as examples. Studies of whale sharks
tagged while aggregating at Ningaloo Reef have shown individuals
transiting through the Timor Sea (Meekan & Radford 2010) but
showed no evidence of aggregation around particular marine
features in the open offshore waters within or in the vicinity of the
Operational Area.

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Matters of MNES Acceptability Demonstration of Alignment as Relevant to the Project

National Considerations (EPBC
Environmental Management
Significance Plans/Recovery
Plans/Conservation
Advices)
Wetlands of N/A N/A
International
Importance
Commonwealth Significant Impact The impact assessment indicates that vessel movements will not
Marine Guidelines for the exceed the Commonwealth Marine Environment significant impact
Environment Commonwealth marine criteria provided in Table 8-1 as the aspect does not pose a
environment (Table 7-3) credible risk.

External Context
There have been no objections or claims raised by Relevant Persons to date around
the vessel movement aspect. Shell’s ongoing consultation program will consider
statements and claims made by stakeholders when undertaking further assessment of
the risks.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements.
Acceptability Summary
As outlined above, the acceptability of the associated risks have been considered in
the context of:
• The established acceptability criteria for the vessel movements aspect
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
The residual risks have been assessed as Dark Blue (minor). Shell considers residual
risks of minor or lower to be acceptable if they meet legislative and Shell requirements.
The discussion above demonstrates that these requirements have been met in relation
to the vessel movements.
Based on the points discussed above, Shell considers the risks from vessel
movements associated with the Prelude petroleum activities to be ALARP and
acceptable.

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9.7.6 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

No injury or mortality of listed Threatened or Fauna observations and incident reports
Migratory MNES species associated with vessel demonstrate no injury or mortality of listed
collisions within the Operational Area. Threatened or Migratory MNES marine species as
a result of vessel movements within the
Operational Area.

9.8 Introduction of Invasive Marine Species from Vessels

9.8.1 Aspect Context

Invasive Marine Species (IMS) are non-indigenous marine fauna or flora that have
been introduced into an area beyond their natural geographical range, and may have
the ability to survive, reproduce and establish a population such that they threaten
native species through increased competition for resources and/or increased predation.
The vessels and equipment sourced from outside Australian waters have the potential
to introduce or transfer IMS to the Operational Area, which may potentially spread to
new areas or increase the impact of IMS already established in the wider region
through oceanic currents and transport via activities such as support vessel
movements. There are two primary mechanisms which may cause the inadvertent
introduction and spread of IMS; hull fouling (biofouling) and ballast water discharges.
Establishment of IMS in the Operational Area requires a sequence of events to occur:
• the potential IMS must be present on (e.g. biofouling) or in (e.g. ballast water) the
vector; and
• the potential IMS must be released into the environment (e.g. ballast water discharge,
release of propagules from biofouling); and
• the potential IMS must survive, reproduce (either sexual or vegetative reproduction) and
subsequently persist in the environment.
The introduction of IMS is recognised globally as a threat to marine biodiversity, and
the International Maritime Organisation (IMO) has developed guidelines for the
management of biofouling and ballast water. Commonwealth, State and Territory
authorities also regulate the risk of IMS from biofouling and ballast water. Vessels
operating in Australia are required to meet these requirements, and vessels meeting
these requirements pose an inherently lower risk of harbouring IMS or releasing IMS
into the environment.
If potential IMS become established in the Operational Area (i.e. on the Prelude FLNG,
from tankers or other vessels), support vessels that operate in the field may
subsequently provide vectors for translocation of potential IMS to new areas
(NOPSEMA, 2020) or increase the impact of IMS already established in the wider
region (Department of Fisheries, 2017). The likelihood of this sequence of events is
considered extremely remote given the controls that are routinely applied to vessels
(e.g. anti-fouling coating, inspections, hull cleaning etc.), the remote offshore location
and nature of typical vessel activities (e.g. short periods alongside the Prelude FLNG
during operations).

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The Prelude FLNG facility will take up and discharge ballast water regularly as it
produces cargoes and exports the products to off take tankers, but this ballast water
does not pose a credible threat as the FLNG facility is permanently moored and does
not travel to or from other ports. Support vessels will generally come from Australian
ports and typically stay alongside the Prelude FLNG for short durations (generally in
the order of hours) to offload and load materials.
Most native fouling species likely to be encountered within or transiting through the
Operational Area will be widely distributed as similar habitats are broadly represented
in the Timor Sea and Browse Basin. An IMS may compete with these native species if
it were to become established in the Operational Area or wider region. This may
decrease the species diversity of benthic communities.
IMS are typically extremely difficult to eradicate once established and reproducing in an
area. In the highly unlikely event, an IMS becomes established and reproductively
viable, it would be almost impossible to eradicate.
Ballast water exchange needs for the support vessels are expected to be limited. All
vessels operating in the Operational Area are obliged to conduct ballast tank
operations in line with IMO guidelines and, where applicable, comply with the
Biosecurity Act 2015.
All known and potential introduced marine pests listed by Australian agencies are
nuisance foulers, predators, invasive seaweeds or noxious dinoflagellates that inhabit
harbours, embayment’s, estuaries, shorelines and/ or shallow coastal waters less than
200m deep (Hayes et al. 2004, Barry et al. 2006). The water depth in the Operational
Area is in excess of 240 m.
The offshore environment of the Operational Area is relatively deep, oligotrophic
(nutrient-poor) and hard substrate habitats do not naturally occur. Many potential IMS
are sessile invertebrates that require hard substrate for attachment. In the unlikely
event potential IMS are released into the Operational Area, the IMS are highly unlikely
to encounter suitable substrate for settlement and establishment. Most potential IMS
are adapted to coastal waters, such as ports and harbours. If a potential IMS were to
become established in the field, it is unlikely to survive in the relatively deep-water
offshore environment. The deep water, low nutrient and open ocean environment in
Operational Area provides minimal larval retention times or suitable habitat for coastally
adapted IMS.

9.8.2 Current Knowledge about IMS on Prelude FLNG and Associated

Vessels
Various studies were conducted both prior to and after the Prelude FLNG arrived in the
Operational Area in July 2017, which provides more certainty on the presence/absence
or persistence of potential IMS. A detailed summary of the outcomes and timing of
various monitoring measures is outlined in Figure 9-6 below.

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Sea chest inconclusive presence of: IMS Expert review concluded no

• Crassostrea virginica suspected IMS of Concern
• Mnemiopsis leidyi detected. Biofouling on the hull
• Psuedo-nitzschia seriata consisted mainly of filamentous
Jun 17 - Jul 17 • Gymnodinium catenatum green algae, gooseneck and acorn
Prelude FLNG Sailed from *18S assay does not bind to Didemnum spp, barnacles, oysters and possibly
Apr 16 - Apr 16 Geoje to Browse Basin such as D. perlucidum or D. vexillum tubeworms. Occasional patches of
Attempt #1 **samples had been treated with sodium white colonial ascidian resembling
Sampling of submerged hypochlorite - possible that any DNA based Didemnum perlucidum had been
hull for IMS of Concern Aug 17 - Sep 17 detections may be from ‘dead organisms’ observed.
ROV Inspection of
Prelude
Jul 16 - Jul 16 Apr 17 - Jun 17in Browse Basin
Dec 17 - Dec 17 Dec 18 - Dec 18 Dec 19
Attempt #2 In water cleaning 2nd ROV Inspection of IMS Expert Review IMS Expert Review of
Sampling of submerged Inc. verification with Prelude in Browse Basin of Nov 2018 Survey Sep 2019 Survey
hull for IMS of Concern VideoRay ROV Feb 18 - Mar 18
eDNA sampling

Apr 19
Jul 16 Oct 16 Jan 17 Apr 17 Jul 17 Oct 17 Jan 18 Apr 18 Jul 18 Oct 18 Jan 19

Apr 16 Sep 19 Dec 19

IMS Inspector noted the Nov 18 - Nov 18 ROV inspection
potential presence of ROV inspection on Hull
• S. clava, C. intestinalis, On Hull
• C. gigas
• Didemnum sp.
Potential IMS identified:
• Asterias amurensis IMS Expert review concluded
Sea chest gratings:
• Styela clava remaining risks for only the
• tubeworms, sponges, and gooseneck
• Ciona intestinalis and C. savignyi following IMS species:
barnacles.
• Amphibalanus eburneus • single S. clava was detected • Didemnum perlucidum
• The Didemnum sp. present also
• Codium fragile fragile (appeared to be dying) (medium)
resembles D. perlucidum, the introduced
• Magallana gigas • detected what could be • Amphibalanus eburneus
colonial ascidian to WA.
• Arcuatula senhousia Didemnum sp. Colonies (very low risk)
• potential Amphibalanus eburneus and/or
• Didemnum vexillum • persistence of Magallana sp. • Magallana sp. (very low
A. improvisus Or Balanus rostratus
and Mytilus sp. (dying/ dead) risk)

Figure 9-6: Timeline of Prelude FLNG IMS monitoring program since April 2016 until December 2019.

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Pre-arrival of Prelude FLNG in the Operational Area, ‘ALARP Cleaning’ (April - June
2017) was conducted in the Geoje shipyard to reduce IMS numbers and potential
inoculum pressure (and was considered the best practicable risk management
outcome available). Specific to biofouling management, Shell contracted biofouling
specialists to provide advice on the clean-up required as well as inspection services.
Biofouling experts have produced the following reports for Prelude pre-mobilisation:
• International Anti-Fouling System Certificate from Lloyds Register.
• IMS Risk Assessment (BFS1445) – Assessed the risk of Prelude FLNG introducing
IMS of concern to Australian waters. The risk assessment is based on “Infection Modes
and Effects Analysis” (IMEA) for two IMS management scenarios: 1) Do nothing, and 2)
ALARP. The study indicated that ALARP cleaning could vastly reduce IMS numbers and
potential inoculum pressure and was considered the best practicable risk management
outcome available.
• Biofouling Management Plan (BFS1456) – Outlined the proposed biofouling removal
from the FLNG.
• Biofouling/IMS Mitigation and Final Inspection (BFS1476) – Final inspection report
after biofouling removal in Geoje, and the assessment of the residual IMS Risk. The
cleaning effort of the hull achieved a significant reduction in the number of IMS of
concern and their cumulative reproductive potential. Despite residual risk, significant
level of effort was applied in the in-water cleaning campaign. (Biofouling Solutions,
2017a)
Post-arrival of Prelude FLNG in the Operational Area (July 2017) until December
2019, there have been four ROV surveys and one set of eDNA sampling conducted,
with data reviews from the biofouling experts. The updated residual risk assessment
was developed in consultation with IMS agencies (i.e. DPIRD, NT Fisheries,
Department of Agriculture, Water and the Environment (DAWE) after the first post-
arrival ROV survey to agree on an aligned approach to managing IMS risk and the
ongoing adaptive IMS risk management process. The Prelude FLNG Biosecurity
Management Plan (2000-010-G000-GE00-G00000-HX-5798-00003) has been updated
upon new information and understanding of the IMS residual risk.
• Prelude ROV Inspection Report (BFS1499) - the IMS Inspector noted the presence of
S. clava, C. intestinalis, suspected C. gigas and D. vexillum persisting amongst
inaccessible and/or uncleaned areas. IMS of concern which had been detected during
previous inspections or any additional IMS of concern which maybe present within
Korean waters, remained undetected. The Didemnum sp. present resembled D.
perlucidum, the introduced colonial ascidian to Western Australia. This is not surprising
considering the species were confirmed on two other installations in the area (i.e. the
ROV survey and physical sample results post arrival of the neighbouring Ichthys
facilities). (Biofouling Solutions, 2017b)
• eDNA water sampling report from Trace and Environmental DNA (TrEnD)
Laboratory at Curtin University - No IMS of Concern detections in the categories
‘highly probable’, ‘probable’ or ‘possible’. However, the presence of Crassostrea
virginica, Mnemiopsis leidyi, Psuedo-nitzschia seriata and Gymnodinium catenatum
were considered inconclusive. (Curtin University, 2018)
To provide additional context to the studies listed above, Biofouling Solutions
undertook a residual risk assessment (Biofouling Solutions 2018). The report presented
a residual risk assessment including new information from two ROV inspections (2017
and 2018) and eDNA water sampling undertaken by Shell at the recommendation of
WA DPIRD. Water samples were collected from the moonpool and internal seawater
systems via sea strainers on the FLNG. While DNA was successfully extracted from all

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samples collected, the yields of DNA were reported as being low (relative to seawater).
Unfortunately, this could be a consequence of the water samples being collected from
internal seawater systems where sodium hypochlorite is continuously dosed into each
sea chest. DNA degradation could also have occurred during the transit of samples to
the laboratory.
Nevertheless, the eukaryotic nuclear 18S gene (V1-V3) was amplified according to the
TrEnD Lab’s standard operating procedures and the DNA sequences recovered were
queried against a custom database of marine invasive species reference sequences
and compared to the National Centre for Biotechnology Information (NCBI) database
for taxonomic identification to family level.
The results of the eDNA study detected a diverse range of taxa. Potential IMS
detections were screened as either of the following categories; Highly Probable,
Probable, Possible or Inconclusive. From the eDNA samples collected, no IMS of
concern were detected in the Highly Probable, Probable or Possible categories.
The presence of four species were screened as Inconclusive. These included Pseudo-
nitzschia seriata and Gymnodinium catenatum that are species of toxic dinoflagellates
which only cause concern when they form toxic blooms. These blooms are often linked
to increased stress such as excessive pollution or nutrient runoff. The distribution of G.
catenatum in Australian waters is uncertain and species in the genus Pseudo-nitschia
are frequently present throughout Australian waters. The presence of these species is
unable to be fully determined using only 18S sequences, as they cannot be
distinguished from other closely related taxa.
The Biofouling Solutions (2018) report concluded that the results of the eDNA study
were not reliable. This was because the water samples were collected from internal
seawater systems which contained sodium hypochlorite which is known to influence
eDNA analysis. Other factors included that not all native and IMS species of concern
have been sequenced and are available on the NCBI database and that eDNA cannot
distinguish between live and dead cells. Finally, it was concluded that the detection of a
species does not necessarily mean that they originated from the FLNG and could
originate from other sources (such as ballast water discharges from other international
vessels).
Another important point is that while the eDNA results detected the Phylum Chordata,
unfortunately the 18S assay does not bind to Didemnum spp., such as D. perlucidum
or D. vexillum, hence this technique cannot be used for reliable detections.
Furthermore, Curtin University were advised by Dr. Justin McDonald of WA DPIRD,
that D. perlucidum is now so widespread throughout Western Australia that it does not
need to be reported to the WA DPIRD, hence Curtin University did not pursue further
testing of this genus.
The outcome of the residual risk assessment undertaken by Biofouling Solutions
(2018) reported that as of July 2018 there were five IMS of concern that have either
been confirmed and/or have the potential to be present on the FLNG (Amphibalanus
eburneus, Codium fragile, Didemnum perlucidum (unconfirmed), Magallana gigas and
Pseudo-nitzschia seriata). The report further considered the potential for natural spread
and artificial spread via domestic conveyances, where such transportation incorporates
a series of stages along an invasion pathway. In the case of the FLNG such a pathway
constitutes a two-stage stepping-stone process whereby visiting domestic conveyances
become contaminated during an interaction with the FLNG, followed by the subsequent
transfer of viable individuals from the domestic conveyance to high value areas and/or
inshore coastal waters of Australia. The likelihood of these stepping-stone events

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occurring depends on a multitude of variables including the size of the population of

IMS of concern on the FLNG, the reproductive biology and maturity of the IMS of
concern, their larval phenology, the ability of the species to transfer asexually or even
via entanglement, the environmental conditions experienced during the interactions,
the duration and frequency of the interactions, and the availability of appropriate habitat
for larvae or fragments to colonise or be entrained. The interaction of these (and other)
variables is extremely complex and results in a highly stochastic probability of transfer
which makes it extremely difficult to make any meaningful likelihood assessment
beyond a broad consideration of plausibility.
In the event that domestic conveyances were to become contaminated with IMS of
concern via settlement on the external hull or entrainment within internal seawater
systems (including ballast water) from the FLNG, the likelihood of these species being
successfully translocated to high value areas and/or inshore coastal waters of Australia
depends on a whole suite of new selective filters such as the vessel’s frequency,
duration and distance, environmental conditions, proximity and suitability of habitats,
(especially artificial substrates), etc. Biofouling Solutions (2018) concluded that the
likelihood of IMS of concern being successfully introduced from the FLNG to either high
value areas or inshore coastal waters via domestic conveyances is considered to be
very low for all five IMS of concern. Although one species (Didemnum perlucidum
which maybe present on the FLNG but remains unconfirmed, has the greatest
likelihood of being both naturally spread or artificially transmitted from the FLNG to high
value areas such as Browse Island (approximately 40 km form the Operational Area). If
this species were to be introduced to a high value area, it has a theoretical potential to
cause moderate impacts/ consequences. Similarly, Pseudo-nitzschia seriata also has
the potential to cause moderate impacts if introduced into the inshore coastal waters of
Australia.
Based on the uncertainty following the eDNA study (2018), further additional ROV
inspections were undertaken in 2018 and 2019 as listed below.
• Prelude ROV Inspection interpretation – An ROV survey was conducted on the
Prelude hull 12-13 November 2018. IMS expert reviewed the results and updated the
specific residual risk of IMS species. Outcomes of the review indicated that there was no
evidence to suggest the presence of the IMS of concern, Didemnum vexillum. The
survey also confirmed the consistent mortality of Magallana spp. since the arrival of the
FLNG in the Operational Area this is because the genus is beyond its temperature and
reproductive tolerance and will slowly die out given there is unlikely to be fresh
recruitment. The IMS expert review identified a morphologically similar growth
resembling Didemnum to be present on the general hull and on sea chest gratings.
However, whether this growth is in fact D. perlucidum can only be confirmed via sample
collection and genetic testing. Pseudo-nitzschia seriata, Gymnodinium catenatum and
Codium fragile fragile were all not observed during the latest and previous post arrival
ROV surveys. Amphibalanus eburneus (acorn barnacle) may persist in turret area.
Although in order for species to persist, individuals need to be in high abundance and
within close proximity in order to cross-fertilise. Even if they do reproduce, the
competency period of larvae is too long to enable an F2 generation to re-establish on
the hull, hence all individuals are likely to die of old age over time.
Based on the Dec 2018 IMS expert review of the survey data available, individual IMS of
concern’s residual risk of being transmitted to high value areas or inshore waters of
Australia were deemed to be Moderate or lower which corresponds to a risk ranking of
Dark Blue in Table 9-32. This assessment was subsequently reviewed by NT DPIRD
and WA Department of Fisheries in February 2019 and the outcome of the residual risk
assessment was aligned.

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• Prelude ROV Inspection Report (BFS1629) - An ROV survey was conducted on the
Prelude hull 19 September 2019. Overall, the assemblages of biofouling observed by
the IMS expert on the FLNG were moderately diverse and abundant, varying from 40-
100% coverage and were typical of biofouling communities associated with offshore
structures located in the Northwest Shelf region of Western Australia. Observations of
paint conditions show that the anti-foul coating is generally in good condition though
significant delamination/damage was observed in one location. The report concluded
“no IMS of concern when reviewing the footage but did observe that white colonial
ascidians with a colony structure and basic morphology resembling colonial ascidians of
in the genus Didemnum were widely distributed on the vessel. This group includes
Didemnum perlucidum which is considered an IMS but is now confirmed to be widely
distributed throughout Western Australian coastal waters.” Although the species is no
longer considered a noxious fish in Western Australian waters with the exception of the
Montebello Islands. (Biofouling Solutions, 2019).
The ROV inspections and the eDNA studies to date confirm that the likelihood of the
FLNG as a source of introducing IMS of concern is very low based on either natural or
artificial transfer to new areas, with no IMS of concern on the Prelude hull since arrival
in field in 2017.

9.8.3 Description and Evaluation of Impacts and Risks

A range of environmental sensitivities within the following groups may be at risk from
the introduction of potential IMS, including:
• Biological Environment
• Socio-economic environment.
Potential risks associated with IMS establishment as a result of the petroleum activities
are discussed below.
Biological Environment
The introduction and subsequent establishment of IMS could result in changes to the
structure of benthic communities leading to a change in ecological function due to
predation of native marine organisms and/or competition for resources. Once IMS
establish, spread and become abundant in coastal waters some species could have
Major ecological, economic, human health and social/cultural consequences (Hewitt et
al. 2011; Pimental et al. 2000).
Shallow water, coastal marine environments are susceptible to the establishment of
invasive populations, with most IMS associated with artificial substrates in disturbed
shallow water environments such as ports and harbours (e.g. Glasby et al. 2007;
Dafforn et al. 2009a, 2009b).
Benthic communities within the operational area are characterised by low density
epibenthic communities of deposit and filter feeders on bare sediments. The seabed
within the entire Operational Area does not receive sufficient sunlight to support benthic
primary producer habitat, such as macroalgae and zooxanthellate corals. Very few
potential IMS identified can credibly survive in the water depths of the Operational
Area. For example, the non-oceanic species identified in the Australian Marine Pest
Monitoring Manual (Department of Agriculture, Fisheries and Forestry 2010) indicated
very few IMS (aside from planktonic oceanic species such as dinoflagellates) could
credibly survive in the Operational Area; only three (European clam, soft-shell clam and
Northern Pacific sea star) were identified as potentially surviving in > 90 m water depth;
none were identified as credibly surviving at > 200 m water depth. These three species
are typically found in shallower, coastal waters. The Operational Area is all > 230 m

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water depth. In the highly unlikely event these species were introduced into the
Operational Area, they are unlikely to survive or become established on natural
substrate due to the water depth alone.
With the stated controls in place, the likelihood of introduction of IMS associated with
specific vessel-based campaigns is considered extremely remote as the potential
vectors (e.g. support vessels) will typically be near the FLNG for relatively short periods
(up to a week). Further, general support vessels will typically be sourced from
Australian waters and will undertake the required assessments described in the
Prelude FLNG Biosecurity Management Plan.
The waters associated with benthic communities (shoals, banks reefs and island
surrounds), some KEFs (e.g. ancient coastline), WA mainland coastline and some of
the Commonwealth Marine Environment in the wider region are typically shallower than
those of the Operational Area. As outlined above, most potential IMS require shallower
habitats than those found in the Operational Area. Hence, these shallower habitat
waters in the region may be more vulnerable to introduction of IMS, however it is
completely dependent on the extremely rare event of subsequent transport by support
vessels.
With consideration of the habitat preferences of IMS (shallow water environments), the
closest shallow water habitat to the Prelude FLNG is Browse Island, located some 40
km south-southeast of the Operational Area, and it is neither disturbed nor contains
artificial structures that IMS are reported to prefer. Although not part of the petroleum
activity, support vessels may spend some time during cyclone season or inclement
weather to seek shelter near Browse Island (or other banks, shoal or islands in the
area) for safety reasons. With the stated controls in place to minimise potential IMS
risk, direct introduction of IMS to a shoal, bank or island during these short-duration
and infrequent sheltering events is considered extremely remote.
Socio-economic Environment
The socio-economic receptors from IMS introduction / establishment risk are industries
outside of the Operational Area such as fishing, tourism/recreation, marine protected
areas or other oil and gas operators (e.g. Inpex Ichthys). The likelihood for IMS
introduction, establishment and survival at or within these receptors is extremely
remote with the stated controls in place.

9.8.4 Risk Assessment Summary

Table 9-32: IMS Evaluation of Residual Risks
Consequence

Residual Risk
Likelihood

Environmental Receptor

Evaluation – Unplanned Risks

Major A - Extremely
Biological Environment Dark Blue
effect remote
Socio-Economic Environment Major A - Extremely
Dark Blue
effect remote

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9.8.5 ALARP Assessment and Environmental Performance Standards

Table 9-33: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
Elimination No vessels No Vessels are essential for supply, standby N/A N/A N/A
safety support, and operations.
Substitution Only use local support vessels No Although the use of local vessels is N/A N/A N/A
preferred, there are cases when this is
impracticable due to availability of
specialised vessels for the activities.
Engineering Anti-foul coating/anti-foul Yes Anti-foul coating/system on the FLNG/ 6.1 Vessels (of appropriate Valid International anti-
system vessels will help prevent biofouling class) will have an anti- fouling systems
accumulation on the hull. foul coating applied in certificate or a
accordance with the Declaration on anti-
It is noted that anti-foul systems must be prescriptions of the
maintained in good condition in order to fouling systems.
International Convention
be an effective control for the on the Control of Harmful Records of
management of marine pests. Therefore, Antifouling Systems on implementation of the
the implementation of the Prelude FLNG Ships (2001) and the Prelude FLNG
Biosecurity Management Plan will Protection of the Sea Biosecurity Management
confirm that vessels maintain Low Risk (Harmful Antifouling Plan.
with respect to IMS, in conjunction with systems) Act 2006 9.
the presence of valid anti-foul
coating/system documentation.
Administrative Ballast Water Management Yes Vessels that are intending to discharge 6.2 Vessels coming from Records of the Maritime
and Procedural Plan and Certificate internationally sourced ballast water overseas will have Arrivals Reporting
controls within Australian waters must submit a required DAWE System (MARS) or

9 Advice from the Registered Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
Ballast Water Report through Maritime clearance including the equivalent demonstrate
Arrivals Reporting System (MARS) at Ballast Water Certificate the vessel has sufficient
least 12 hours prior to arrival to gain and Ballast Water DAWE clearance to
DAWE clearance. Management Plan if the operate within the
The acceptable area for a ballast water vessel is required to Operational Area and
exchange between an offshore oil and discharge ballast in Australian Territorial
gas installation and an Australian port is Australian waters. Waters.
in areas that are no closer than 500 m
from the offshore installation and no All vessels (incl. Vessel Ballast Water
closer than 12 NM from the nearest land domestic) shall have a Management Plan
and in water at least 50 m deep. Ballast Water
Ballast tank sediment must be disposed Management Plan in
of in an area outside 200 nautical miles place consistent with the Vessel Ballast Water
from the nearest land, and in at least a IMO Ballast Water Certificate
depth of 200 metres, or at an approved Convention’s Guideline.
land-based reception facility.
The Biosecurity Act 2015 requires that
vessels have a Ballast Water
Management Certificate and Ballast
Water Management Plan (BWMP), and
undertake reporting and management of
ballast in accordance with the Act.
The BWMP must:
• be vessel specific (vessel name and
International Maritime Organization
(IMO) number)
• be approved by a survey authority,
recognised organisation, or the vessel’s
flag administration
• nominate the rank(s) of the responsible
officer and crew

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
• contain the ballast water management
method and pumping rates.
BWMPs should be consistent with the
IMO Ballast Water Convention’s
Guidelines for Ballast Water
Management and Development of
Ballast Water Management Plans (G4
Guidelines).
A valid Ballast Water Certificate must be
issued by either a survey authority,
classification society, or the
administration of the vessel, and be in
accordance with Regulation E-1 of the
Ballast Water Convention.
Ballast water management Yes Only low risk ballast water will be 6.3 Only low risk ballast Sample ballast exchange
within the Operational Area discharged within the Operational Area. water will be discharged logs for internationally
Although the Prelude FLNG facility within the Operational sourced vessels and
location is classified as a suitable Area. offtake tankers
location for ballast exchange per the demonstrate only low risk
Australian Ballast Water Management ballast water has been
Requirements i.e. will occur > 12 Nm discharged within the
from land and in water depths > 50m Operational Area.
deep, no ballast water (originating from
outside Australian waters) exchange will
occur within the Operational Area of the
FLNG. The product carriers and other
international vessels will exchange their
ballast before arriving at the Operational
Area, therefore, they will discharge only
low risk ballast water at the facility.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
Administrative Vessel Specific Biofouling Yes IMO biofouling guidelines - Guidelines 6.4 Vessels will have a Vessel-specific Biofouling
and Procedural Management Plans for the control and management of ships’ Biofouling Management Record Book (BRB)
controls biofouling to minimise the transfer of Plan as per IMO recording implementation
invasive aquatic species is considered guidance. of BMP.
‘best practice’ for mitigation of transfer of
invasive aquatic species to ALARP.
Vessel specific (as per IMO guidance)
Biofouling Management Plan (BMP) and
Biofouling Record Book (BRB) recording
implementation of BMP.
Administrative Prelude FLNG Biosecurity Yes The Prelude FLNG Biosecurity 6.5 Adhere to class Records of hull
and Procedural Management Plan Management Plan applies to the FLNG requirements for marine inspections
controls and associated support/installation vessel hull integrity
vessels. The plan details preventative inspection frequency (In-
control measures to cover aspects of water every 2.5 years,
biofouling management, ballast water Dry-dock every 5 years).
management and non-marine biosecurity
risk. These controls include;
• biofouling management record book
Carry out the required
• biofouling risk assessments for Marine Vessel Biofouling Prelude Biosecurity LOW
vessels operating within the Prelude Risk Assessments risk status from DAWE
PSZ aligned with National
Vessel Low Risk
• valid anti-foul coating certifications Biofouling Guidelines for
Biosecurity Status
the Petroleum Production
• ballast exchange logs Biofouling Risk
and Exploration Industry
• treatment of internal seawater – for vessels originating Assessments for vessels
systems from overseas or vessels operate within Prelude
PSZ
• vessel sharing biofouling risk being shared between
assessment for domestic operators.
movements (refer Figure 10-13).
The following FLNG-to-vessel

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
interactions are exempted from this
exposure:
• Transfer of products (ex. LNG, LPG, condensate,
diesel) via the offloading arms or hoses.
• Offloading of equipment from another vessel onto
the FLNG, but the equipment will be deployed
directly to the seabed.
• Transfer of pilots to support vessels during pilotage
of product offtake tankers.

Consistent with the published Biosecurity

Reference Case by Maritime Industry
Australia (Oct 2020), biofouling risk
assessments shall include
considerations of:
• periods of layup/inactivity since last
dry dock
• details of antifouling system applied
• presence or absence of MGPS
• information about previous vessel
locations.
Risk results:
• Low risk: vessel can be hired for
normal operations
• Uncertain/high risk: not to be used
for normal operations
Under unplanned or emergency
circumstances where there is potential
for escalated safety or environmental
risk, uncertain/high risk vessels may be
used as part of the response. In which
case IMS risk assessments shall be

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
conducted retrospectively and risk
managed accordingly.
Administrative Conduct opportunistic 3rd Yes UWILD as required by Class ensures the 6.6 Conduct a 3rd Party IMS 3rd Party IMS review
and Procedural Party IMS Review during functionality of antifouling coating and review associated with report associated with
controls supply vessel class systems of vessels. A 3rd party IMS support vessel UWILD support vessel UWILD
Underwater Inspection In Lieu review of the footage and photos taken and dry docking. and Dry Docking.
of Drydocking (UWILD). during the UWILD will provide even more
certainty on the vessel’s biofouling
status.
Administrative Limit time for support vessels No The latest Biosecurity Reference Case N/A N/A N/A
and Procedural to be alongside the FLNG and (Oct 2020) states that vessels with low
controls in ports, if vessels deemed low risk biofouling status (such as the supply
risk. vessels and ISVs) do not require a time
limit for operating alongside a facility with
low risk biofouling status (such as the
FLNG); unless the biofouling status is
uncertain or high. Therefore, limiting the
time spent by supply vessels and ISVs
alongside the FLNG is not considered an
effective control.
Administrative Conduct routine IMS surveys No Leading up to Prelude’s arrival in N/A N/A N/A
and Procedural on the Prelude Hull and Australia in June 2017 there was
controls associated sampling of significant biosecurity monitoring and
potential IMS species. management activities implemented to
minimise the risk of introducing any IMS
into Australian territory via Prelude.
Although significant monitoring and
management took place prior to sail-
away, there was still a residual level of
risk that remained at the time of sail-
away.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
In order to follow-up, ROV hull surveys
were carried out in the months following
Prelude’s arrival in September 2017 and
again in January 2018 to inspect whether
the species which could not be removed
from the hull were surviving in WA-44-L.
The results of these surveys found all of
those IMS present before sail-away were
gone with some remaining uncertainty
regarding the presence of Didemnum
vexillum (often confused with Didemnum
perlucidum which has already been
introduced in WA waters). Further
monitoring in the form of eDNA water
monitoring was undertaken in March
2018 and the results were inconclusive
although feedback from WA DPIRD was
that it was not on the list of IMS of
concern due to it being widespread
throughout WA.
Further IMS specific ROV surveys were
conducted on the Prelude FLNG hull in
2018 and 2019. The surveys were
reviewed by independent IMS expert and
concluded no IMS of concern have been
identified. The results and assessments
of the subsequent ROV surveys were
reviewed by NT DPIRD and WA
Department of Fisheries which confirmed
their alignment on the residual risk.
The financial and potential H&S costs of
conducting dedicated IMS Hull surveys
or physical sampling of potential IMS is
considered grossly disproportionate to

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
the benefit where the gain in terms of
overall risk reduction is negligible in the
context of the monitoring results since
2017 and the additional controls placed
around periodic IMS reviews for supply
vessels which are the main vectors for
potentially spreading IMS.
It is noted that IMS reviews of Prelude
Hull surveys has to be dedicated
campaigns at an additional cost due to
the technical requirements of the
necessary footage.
Administrative Conduct IMS Reviews on the Yes Although it is disproportionate to conduct 6.7 Conduct a 3rd Party IMS 3rd Party IMS Review
and Procedural Prelude Hull and associated regular IMS reviews of the Prelude Hull review of Prelude Hull report from a Prelude
controls sampling of potential IMS and eDNA sampling, it is feasible to Survey triggered by a Hull Survey
species, when triggered by a conduct this review if triggered by the support vessel IMS
support vessel IMS review or support vessels’ IMS reviews identifying review (i.e. identified IMS
conducted at least once within IMS of concern or conducted once within of concern), or at least
the 5 year period of the EP. period of 5 years. once within the 5 year
period of the EP.
Administrative eDNA water sampling within No eDNA analysis of water samples from N/A N/A N/A
and Procedural Ports visited by vessels going the port will be inconclusive as to
controls to and from the Operational whether the risk has originated from the
Area petroleum activities due to the number of
users of the port. As agreed by the State
marine biosecurity agencies, this is the
responsibility of the State agencies.
Administrative Further investigation of No The biology of each species needs to be N/A N/A N/A
and Procedural biology, method of considered to determine the likelihood of
controls reproduction, propagule the species reproducing, spreading and
pressure/competency periods contaminating both nearby and distant
and behaviour, ability for sensitive receptors and/or anthropogenic

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
adults to depart the FLNG, structures. This might involve
oceanic currents, interaction investigating each species’ methods of
with vessels and domestic reproduction (e.g. sexual and asexual),
ports potential larval/propagule pressure
based on assessed abundance and
density witnessed on the Prelude FLNG,
larval/propagule competency periods
and behaviour, ability for adults and/or
fragments to depart the vessel, strength,
direction and prevailing oceanic currents,
interaction with domestic conveyances,
and their interaction with domestic ports
of Australia. Such an assessment is
complex, time-consuming and will suffer
from significant knowledge
gaps/uncertainty.
Administrative In-water cleaning of the No Limited availability of suitable cleaning N/A N/A N/A
and Procedural FLNG’s hull methodology – Only two cleaning
controls methodologies have been approved by
the paint/coating provider for the Prelude
FLNG: caviblaster and robotic/ROV
cleaner provided by Samsung Heavy
Industry. Other technologies have been
considered and tested in Geoje (South
Korea), but were determined not to be
suitable as they will damage the coating,
therefore, voiding the intended
functionality of the coating and the
warranty.
The robotic/ROV cleaner can only
access flat areas, but will not be able to
clean the niches. The caviblaster will
require divers. Not all areas can be
cleaned by the ROV cleaner, and divers

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
will be required which present a
significant safety exposure (diving in an
offshore environment, and under a
weathervaning facility).
The indicative total cost would likely be
more than $10 million per cleaning
activity. This cost is disproportionate to
the benefit gained as any in-water
cleaning approach does not give
certainty to the removal of all potential
IMS. Cleaning will also result in
disruption to operations in order for the
sea-chest gratings to be cleaned as
water intakes have to be shutdown which
will cause disruption to normal seawater
supply into the facility. Therefore, in-
water cleaning may result in
considerable operational disruption
which will result in significant costs.
As there will always be residual risk of
IMS even after in-water cleaning
(regardless of any cleaning technology
used or even if the removed biofouling
are contained) and this has been
deemed as acceptable under the Shell
risk assessment methodology, there is
therefore limited benefit of in-water
cleaning at such a disproportionate cost
and safety risks. Therefore, in-water
cleaning is not considered ALARP.
Administrative Develop specific IMS No The resources and time that would be N/A N/A N/A
and Procedural response plans and carry out needed for a mitigative control such as
controls training and drills to prepare this is significant and considered grossly

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance
Standard (EPS)
for the need to respond to an disproportionate to the benefit gained
IMS incident since the time it would take to prepare a
response plan in the event of an incident
is not considered to be significant in the
context of breeding and reproductive
cycles of most potential IMS species.
Furthermore, IMS response plans are
planned to be developed by government
as outlined in the National Strategic Plan
for Marine Pest Biosecurity 2018-2023.

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9.8.6 Acceptability of Impacts and Risks

Table 9-34: Acceptable Levels of Risks - IMS

Receptor Receptor Sub- Acceptable Level Are the Acceptability Assessment

Category category of Impact Impacts of
an
Acceptable
Level?
Biological Benthic communities Limited Yes The introduction of an IMS as a
Environment environmental result of the Prelude operations
impact which is unlikely to survive given the
directly impacts water depth in the Operational
bare sediment Area. However, surrounding
benthic habitats shallower habitats in the wider
outside of the region such as Browse Island
Operational Area (the closest receptor to Prelude,
as a result of the approx. 40 km away) are likely
petroleum activities to be more susceptible to an
which adversely IMS becoming established due
effects biological to their relatively shallow depth.
diversity or Based on ongoing controls such
ecological integrity. as using a risk-based approach
Limited to manage the pathways and
environmental vectors that are responsible for
impacts to high- the establishment of an IMS, the
value sensitive likelihood of an IMS becoming
benthic established is extremely remote.
communities Shell will take industry-standard
(corals, measures to reduce the
macroalgae, likelihood of an IMS being
seagrasses and introduced at the Operational
mangroves) Area or to new areas as a result
associated with of petroleum activity.
named reefs,
banks and shoals. If an IMS were to be become
established, it would be very
difficult to eliminate, however
there is an extremely remote
likelihood of significant impacts
to the identified potential
receptors.
KEFs No impacts to Yes
environmental
values of KEFs

Commonwealth Marine No significant Yes

Area impacts to the
Commonwealth
Marine
Environment (Refer
to Table 8-1).
WA Mainland Coastline No impacts to Yes
mainland coastline.
Socio- Marine Protected Areas No impacts to Yes Based on ongoing controls such
economic and ecological values of as using a risk-based approach
Cultural Marine Protected to manage the pathways and
Environment Areas vectors that are responsible for
the establishment of an IMS, the
Fishing Industry No negative Yes
impacts to

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Receptor Receptor Sub- Acceptable Level Are the Acceptability Assessment

Category category of Impact Impacts of
an
Acceptable
Level?
exploited fisheries likelihood of an IMS becoming
resource or established is extremely remote.
aquaculture stocks Shell will take industry-standard
which result in a measures to reduce the
demonstrated likelihood of an IMS being
direct loss of introduced at the Operational
income or other Area or to new areas as a result
benefits. of petroleum activity.
Tourism and No negative Yes
Recreation impacts to nature-
based tourism
resources resulting
in demonstrated
loss of income.

The assessment of risks from IMS determined a residual risk ranking of Dark Blue
(Table 9-32).As outlined above, the acceptability of the risks from the introduction of
IMS associated with the petroleum activities has been considered in the context of:
Principles of ESD
The inherent risks from the introduction of IMS resulting from the petroleum activities
are inconsistent with some of the principles of ESD based on the following:
• The introduction of an IMS poses a risk to the diversity and ecological integrity of the
biological and socio-economic environments in the vicinity of the Operational Area and
the wider region.
However, Shell will apply a range of controls to ensure that the risk of IMS introduction
is reduced to a level that is acceptable and ALARP. Following successful application of
these controls, Shell considers the residual risk to be consistent with the principles of
ESD.
Relevant Requirements
Management of the risks from an introduction of IMS resulting from the Prelude project
are consistent with relevant legislative requirements, including:
• compliance with international maritime conventions, including
o The International Convention for the Control and Management of Ships’ Ballast
Water and Sediments
o The International Convention on the Control of Harmful Anti-Fouling Substances
o IMO 2011 Guidelines for the control and management of ships’ biofouling to
minimise the transfer of invasive aquatic species.
• compliance with Australian legislation and requirements, including:
o Protection of the Sea (Harmful Anti-fouling Systems) Act 2006:
 Marine Order 98 – Marine Pollution prevention – anti-fouling systems.
o Biosecurity Act 2015:
 National Biofouling Management Guidelines
 Australian Ballast Water Management Requirements.

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o NT Fisheries Act
o WA Fish Resources Management Act 1994, subsequent Fish Resources
Management Regulations 1995 and the Aquatic Resources Management Act 2016
o the WA DPIRD Biofouling Biosecurity Policy*.
*The WA DPIRD Biofouling Biosecurity Policy (WA Department of Fisheries Jan 2017)
specifies the objective to minimise the adverse impacts of aquatic pests and diseases
in WA through “1. Preventing the establishment of aquatic pests and diseases in new
locations” and “2. Minimising the impact of established aquatic pests and diseases”. As
such, the acceptable level of risk for IMS (stated in the EPO) is consistent with this
policy.

Matters of National Environmental Significance

Threatened and Migratory Species
The policies, strategies, guidelines, conservation advice and recovery plans for MNES
that may occur within the potential area affected by an IMS do not identify IMS as a
threat.
Commonwealth Marine Environment
The impacts and risks from the introduction of IMS will not result in significant impacts
to the Commonwealth Marine Environment.

Table 9-35: Summary of Alignment of the Risks from the IMS Aspect of the Prelude
Petroleum Activities with Relevant Requirements for EPBC Threatened Fauna

Matters of MNES Acceptability Considerations Threats Demonstration of Alignment

National (Significant Impact Criteria, EPBC Relevant to as Relevant to the Project
Environmental Management Plans/Recovery the Project
Significance Plans/Conservation Advices)
Threatened and N/A N/A N/A
Migratory Species
Commonwealth Significant Impact Guidelines for the Introduction The residual risk assessment
Marine Area Commonwealth marine environment of IMS indicates that the petroleum
(Table 8-1) activities will not exceed the
Commonwealth marine
environment significant impact
criteria provided in Table 8-1.
Wetlands of N/A N/A N/A
International
Importance

External Context
Shell’s ongoing consultation program will consider statements and claims made by
stakeholders when undertaking the assessment of impacts and risks.
Ongoing monitoring and engagement with Relevant Persons for IMS will be carried out
in accordance with the process below established in agreement with the Relevant
Persons as further described in Section 10.4.3 and Figure 10-12 with respect to the
adaptive management of IMS.
The following claims were made by DPIRD regarding controls to consider:

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• Suggest support vessels which aligns with proposed “NOPSEMA Offshore Support
Vessel Reference Case” process. – Shell has reviewed the published Biosecurity
Reference Case (Maritime Industry of Australia Ltd, 2020) and has ensured alignment.
The associated NOPSEMA regulatory advice states that reference case delivers a
suitable evaluation of impacts and risks and appropriate control measures for: the
management of ballast water risks; and the biofouling risks associated with vessels
coming from within the same region (locally-sourced) operating in less sensitive areas
(e.g. deep water) and alongside low risk facilities (e.g. facilities with no known
established NIMS).
• IMO biofouling guidelines considered ‘best practice’ for mitigation of transfer of invasive
aquatic species to ALARP – Shell has adopted this.
• Suggest supporting vessels encouraged to have vessel specific (as per IMO guidance)
Biofouling Management Plan (BMP) and Biofouling Record Book (BRB) recording
implementation of BMP. – Shell has adopted this.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements.
Acceptability Summary
The assessment of risks from IMS determined the residual risk rankings were Dark
Blue (Table 9-32). As outlined above, the acceptability of the impacts and risks from
IMS associated with Prelude Field has been considered in the context of:
• The established acceptability criteria for the IMS aspect of the Prelude field
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
Given the considerable water depth (>230 m), potential IMS species which may be
present on Prelude FLNG would not able to settle and establish on the available
natural substrate within the Operational Area and the nearest shallow water sensitive
receptor, Browse Island, is located approximately 40km away. Considering all of the
controls which are in place, the residual risk of potential species of IMS persisting on
Prelude FLNG, spreading, attaching to support vessel hulls and establishing in new
areas such as high value areas and/or inshore coastal waters of Australia such as at
ports following a long distance vessel transit is Moderate given the potential
consequences following the very remote likelihood of establishment.
Shell considers residual risks of moderate to be acceptable with controls if they meet
legislative and Shell requirements. The discussion above demonstrates that these
requirements have been met in relation to the IMS aspect of the petroleum activities.
Based on the points discussed above, Shell considers the risks from IMS associated
with the petroleum activities to be acceptable.

9.8.7 Environment Performance Outcomes

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Environment Performance Outcomes Measurement Criteria

No IMS of concern 10 established in the No confirmed and externally reported

natural environment as a result of Prelude instances of IMS establishment in the
operations. natural environment as a result of the
petroleum activities.
No introduction of IMS to the marine
environment from ballast water exchange
operations undertaken or biofouling by
project vessels.

9.9 Discharge of Liquid Effluent

A range of aspects of the Prelude petroleum activities will result in the discharge of
liquid waste streams to the marine environment. These aspects include:
• Drainage and bilge effluent
• Food waste, greywater and sewage
• Cooling Water (CW)
• Desalination brine, boiler blowdown and Mixed Bed Polisher (MBP) Effluent
• Produced Water (PW)
• Use and release of chemicals in ad-hoc discharges.
Descriptions of the characteristics of each of the routine liquid discharge streams are
summarised in Table 9-36 and further detailed specifically in Section 9.9.1 below. Note
that unplanned spills, e.g. of chemicals or hydrocarbons, are considered separately in
Section 9.14.
Table 9-36: Types, location, source depth, discharge depth, flow rates and orientations of
the planned and routine liquid discharges from Prelude FLNG

Discharge Discharge Type Port or Starboard Source Typical Orientation Maximum Estimated
Port Depth Below Discharge Flowrate (m3/hr)
Name Sea Level Depth BSL
(BSL) (m) (m)

P47 Sewage Port N/A 11.5 Vertical 0.17-0.43 (Continuous)

20 (Batch)

P50 Grey Water Port N/A 11.5 Vertical 2.4-2.7

P50 Foodwaste Port N/A 11.5 Vertical 0.01-0.03

P6 Produced Water Starboard N/A 5 Horizontal outboard 50-165

10IMS of concern are species that are listed on the Western Australian Prevention List for Introduced Marine
Pests or Commonwealth National Introduced Marine Pest Information System, and could survive in the
natural environment beyond the Prelude FLNG and installed infrastructure.

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Discharge Discharge Type Port or Starboard Source Typical Orientation Maximum Estimated
Port Depth Below Discharge Flowrate (m3/hr)
Name Sea Level Depth BSL
(BSL) (m) (m)

P51 SW1 CW Discharge Port Near Surface 12.1 Vertical 142

P60 SW1 CW Discharge Starboard Near Surface 13 Vertical 142

P61 SW1 CW Discharge Starboard Near Surface 12.6 Vertical 142

P53 SW2 CW Discharge Starboard 150 5.4 Horizontal to stern 14000

P54 SW2 CW Discharge Starboard 150 5.4 Horizontal to stern 14000

P63 SW2 CW Discharge Starboard 150 5.4 Horizontal to stern 14000

P64 SW2 CW Discharge Starboard 150 5.4 Horizontal to stern 14000

P48 SW3 CW Discharge Starboard Near Surface 17.2 Vertical 4028

P49 SW3 CW Discharge Port Near Surface 17.2 Vertical 4028

P35 SW4 CW Discharge Port Near Surface 6.2 Horizontal Outboard 1750

P36 SW4 CW Discharge Port Near Surface 6.2 Horizontal Outboard 1750

P37 SW4 CW Discharge Port Near Surface 6.4 Horizontal Outboard 1750

P59 Desalination Brine Starboard N/A 12 Vertical 1100

P30 Boiler Blowdown Starboard N/A 18.5 Vertical 14-30

P38 MBP Effluent Port N/A 12 Vertical 200

P62 Drainage effluent Port N/A 11.5 Vertical 15.8

P39 Bilge Starboard N/A 19 Vertical 18

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9.9.1 Aspect Context

Figure 9-7: Locations of all routine planned liquid discharges on the Prelude FLNG.
Numbers correspond with those in Table 9-36.

9.9.1.1 Drainage (Slops) and Bilge Wastes

Marine Support Vessels
Deck drainage and bilge from Marine support vessels consists mainly of wash down
water, seawater spray and rainwater and may contain small quantities of oil, grease,

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metals, detergents (surfactants) and other residual chemicals present on the deck,
which has the potential to create surface sheens and short term, localised reduction in
water quality if it enters the marine environment.
FLNG
The FLNG Open Hazardous Drainage System collects and disposes both deck
drainage (e.g. rain water), potentially oil contaminated streams (e.g. deluge water,
accidental spills, and cleaning water during maintenance activities) as well as
continuous process drainage streams (e.g. automatic filter backwash, analyser
conditioning systems). When there is deck drainage, the majority of inputs into the
Open Hazardous Drainage system originates from continuous process drainage
sources (~200 m3 per week). All open hazardous drainage sources are directed to the
Open Drain Tanks and then Slops Tanks where it is treated by gravity separation prior
to discharge. The Slops Tanks can also act as a further separation mechanism for
managing Produced Water.
Unlike other LNG facilities, the Prelude FLNG facility has a machinery space and
thrusters. Similar to regular trading vessels, run-off from this area is collected in the
Bilge System and treated prior to being discharged using a unit designed to meet
MARPOL limits.
Runoff from deck areas containing LNG, Mixed Refrigerant (MR) or LPG is not
contained to ensure that cryogenic spills are not left in-situ to develop into flammable
gas clouds on the facility. This is a design safety measure. In the unlikely event of a
spill, the liquefied hydrocarbons would change into a gaseous phase rapidly with
minimal effect on the marine environment. Therefore, in areas where potential
cryogenic spills can occur, Entirely Oil Free streams of storm-water, sea spray and
water generated from routine operations such as deck and equipment cleaning and fire
drills are not collected and contained. To protect the environment from potential spills
during maintenance of hydrocarbon containing equipment in cryogenic areas, spill
equipment is stored onboard the facility to enable the establishment of temporary
containment facilities.
The closed drain system will not have any liquids discharged to the ocean, therefore,
there are no risks or impacts associated with the closed drains systems.
The FLNG’s drainage system is further described in Appendix A: Detailed Facility
Description.
9.9.1.2 Food Waste, Sewage and Greywater
Vessels
Vessel activities within the Operational Area will require planned discharges that will
likely include sewage, greywater and food waste. Typical discharge volumes per vessel
type are provided in Table 9-37. These volumes are indicative only and are provided
for the purposes of the corresponding impact assessment and may vary.
FLNG Facility
The sewage system on the FLNG facility collects black water, some greywater and
sweat drains from the following prior to discharge:
• Accommodation
• Hospital
• Toilets in the aft machinery space.

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The pumps and screens within the vacuum toilet and sewage collection system
effectively comminutes sewage particles. There is a sewage holding tank which was
designed to hold sewage if not appropriate to discharge overboard.
The grey-water system processes the effluent stream from sinks, washbasins,
showers, laundry and sweat drains. Drains from the galley sinks are routed to the grey-
water system. Grey water quantity is greater than black water and can be managed
separately if required. Grey water can be discharged directly overboard or overboard
via the grey water tank.
The food waste system includes a macerator, which discharges to the ocean.
The expected production and release rates of sewage, greywater and food waste for
the FLNG and typical vessels are shown in Table 9-37. These estimates are based on
the anticipated upper bound, assuming peak manning and all listed vessels in the
Operational Area at the same time which is highly unlikely.

Table 9-37: Upper bound estimates of sewage, grey water and food waste volumes and
associated calculated nutrient input estimations into the marine environment

Vessel/Facility Typical Estimated Estimated Estimated Estimated Total Estimated Total

Max Sewage Greywater Food Volume Nitrogen (TN) Load Phosphorus (TP)
POB volume Volume (kg/day)3 (kg/day)4 Load (kg/day)5
(m3/day)1 (m3/day)2

FLNG 340 10.2 57.8 3 Sewage: 1.02 Sewage: 0.09

40 Greywater: 1.52 Greywater: 0.58
Food waste: 8.16 Food waste: 1.36
Total: 10.70 Total: 2.03

Supply Vessel 68 2.0 11.6 68 Sewage: 0.20 Sewage: 0.02

Greywater: 0.30 Greywater: 0.12
Food waste: 1.63 Food waste: 0.27
Total: 2.14 Total: 0.41

Infield Support 10 0.3 1.7 10 Sewage: 0.03 Sewage: 0.003

Vessel
Greywater: 0.04 Greywater: 0.02
Food waste: 0.24 Food waste: 0.04
Total: 0.31 Total: 0.06

Installation 120 3.6 20.4 120 Sewage: 0.36 Sewage: 0.03

Vessel
Greywater: 0.54 Greywater: 0.21
Food waste: 2.88 Food waste: 0.48
Total: 3.78 Total: 0.72

Accommodation 650 19.5 110.5 650 Sewage: 1.95 Sewage: 0.17

Vessel (e.g.
Major Greywater: 2.91 Greywater: 1.12
Maintenance Food waste: 15.6 Food waste: 2.6
Campaign)
Total: 20.46 Total: 3.88

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Vessel/Facility Typical Estimated Estimated Estimated Estimated Total Estimated Total

Max Sewage Greywater Food Volume Nitrogen (TN) Load Phosphorus (TP)
POB volume Volume (kg/day)3 (kg/day)4 Load (kg/day)5
(m3/day)1 (m3/day)2

Total Upper Bound (Rounded) 37 7

1. Calculated based on 0.03m3 per person/per day

2. Calculated based on 0.17m3 per person/per day (USEPA 2011)
3. Calculated based on 1kg per person/per day
4. Conservatively assumes no consumption via vessel treatment systems. Calculated based on sewage
discharge of 100 mg/L TN for sewage (Washington State Department of Health 2005), 26.3 mg/L for
greywater (USEPA 2011) and 2.4% TN for food waste (Polglaze 2003).
5. Conservatively assumes no consumption via vessel treatment systems. Calculated based on sewage
discharge of 8.6 mg/L TP for sewage (State of Idaho Department of Environmental Quality 2012), 10.1
mg/L for greywater (USEPA 2011) and 0.4% TP for food waste (Polglaze 2003).

9.9.1.3 Cooling Water

Vessels
Based on relatively low predicted volumes of cooling water discharged from vessels
coupled with expected rapid dilution and dispersion, these discharges are not
considered to present credible impacts to receptors and are not described further.
FLNG
Seawater is used as a heat exchange medium for the cooling of machinery engines
and in the production process. Seawater is drawn from the ocean and flows counter
current through closed circuit heat exchangers, transferring heat from the machinery or
production process to the seawater via an intermediate circulating freshwater system.
Seawater is then discharged to the ocean at an average of approximately 5°C to 9°C
above the ambient seawater temperature (depending on season and the depth it is
drawn from).
The Prelude FLNG facility has 12 cooling water discharge outlets which are situated
below the water line towards the stern of the facility. They differ by flow rate and
orientation as shown in Table 9-36 and Figure 9-7. The total throughput of cooling
water during normal operations is approximately 80,000 m3/h.
Chlorine in the form of sodium hypochlorite, produced through the Electrochlorination
Unit (ECU), is added to the cooling water to reduce the potential for marine growth
within the pipework of the cooling water system. The entire system is designed for fixed
amount of seawater flowing into the ECU unit. Hypochlorite injection is controlled by
varying the current sent to the ECU cells and the rate at which hypochlorite is dosed
into the various systems. An investigation into a power trip on Prelude in February
2020, which resulted in a shutdown of production on the facility, found a key cause of
the trip to be fouling in the sea water heat exchangers resulting in the trip of the back-
up power system. Details on the investigation into the ECU performance and the
discharge limits based on the current development is further discussed in the section
below. After considering the identified ECU operating constraints, a decision has been
made to operate in a target range of 0.12 – 0.43mg/l and a maximum of 0.6mg/l to
allow for shock dosing.

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Cooling is required for the FLNG facility from a safety and technical integrity critical
perspective as part of the hydrocarbon production process. Therefore, maintaining a
system that is free of internal marine fouling is absolutely integral to the safe and
efficient operation of the facility.
9.9.1.4 Desalination Brine and Mixed Bed Polisher Effluent
The production of freshwater from seawater in the seawater distillers on the FLNG
facility results in a discharge of seawater with a slightly elevated salinity (approximately
10% higher than seawater). The volume of the discharge is dependent on the
operational demand for fresh (or potable) water. Standard demand for freshwater for
the FLNG facility will be approximately 70 m3/hr, however this may be up to 120 m3/hr
during major maintenance activities or other campaigns, which require a greater
number of people to be located at the facility for short periods of time. Chlorine
scavenging, scale inhibiting and/or small volumes of other treatment chemicals may be
present in the waste stream at low concentrations.
Mixed Bed Polisher (MBP) effluent discharge is a batch discharge, characterised in
Table 9-36 and location shown within Figure 9-7. The discharge typically managed to
pH 6-12 and is generated from the requirement to regenerate the mixed bed polishers
to ensure their reliable operation.
The boiler blowdown discharges are associated with water within the boiler system that
is discharged with flashed steam as is the case for many commercial vessels that
utilise marine boiler systems. The boiler blowdown discharge is a continuous discharge
of approximately 2 m3 per hour per boiler. On irregular occasions, when deposits in the
boiler drums have to be removed, approximately 30 m3 per hour may be discharged for
short durations. The discharge is characterised in Table 9-36 and location shown within
Figure 9-7. The discharge typically is managed to a pH between pH 9-12 and also
contains residual chemical additives which are used to prevent corrosion and scale
build-up within the boilers to maintain safe, energy efficient and functional integrity.
9.9.1.5 Produced Water (PW)
PW is water which has permeated into the gas reservoir over time and includes
condensed water. When the liquid and gaseous hydrocarbons are extracted from the
reservoir the PW is separated from the hydrocarbon products in the inlet facilities. PW,
including condensed water, is an undesirable by-product of the gas and condensate
extraction process and is discharged into the marine environment directly from the
FLNG following treatment. The PW discharge is located near the bow, approximately
40 m from the turret, and on the starboard side of the FLNG facility at approximately 5
m below the water line.
The PW treatment system of the FLNG facility is designed for a maximum 165 m3/hr
discharge capacity. However, for the duration of this EP and prior to the breakthrough
of the produced formation water (saline aquifer in the liquid phase), it is anticipated that
discharge of condensed PW (freshwater condensed out of the gas phase through the
process) will occur in batches and at a considerably lower rate of approximately 50
m3/hr.
Hydrocarbons from the PW are treated by the Macro Porous Polymer Extraction
(MPPE) Package. This system is further described in Section 6.0 and Appendix A:
Detailed Facility Description. Treated water from MPPE package is then routed
overboard to sea. The package is designed to discharge PW at less than 42 mg/L Total
Petroleum Hydrocarbon (TPH) content instantaneous and less than 30 mg/L TPH over
a 24hr average. The definition of TPH is documented in Prelude FLNG Oil in Water

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Measurement Philosophy (HSE_GEN_16227). A buffer tank is available to recycle and

retreat PW prior to discharge if it is off-specification.
During initial ramp-up to the maximum flowrate for each well, including the initial
production test runs at up to 200 MMSCFD production, there may also be short time
periods (approximately 72-96 hours per well) where the PW discharge may contain
concentrations of up to 100 mg/L TPH required to complete the well clean-up process
which involves flowing the wells at 100% capacity. During these completions of the
initial ‘clean up’ activities, it is expected each well will produce higher rates of drilling
mud.
As described further in Appendix A: Detailed Facility Description, MEG is used in the
subsea system for hydrate prevention and preservation under certain scenarios. This
may result in PW discharges containing up to approximately 20% MEG for short
durations following these events.
9.9.1.6 Use and Discharge of Chemicals
Chemical usage is required for various routine and non-routine process and non-
process applications and as such, chemicals may be present in waste water streams
which are discharged to the ocean.
Chemicals are utilised on the Prelude FLNG facility, marine support vessels and
associated subsea facilities for a variety of purposes and can be divided into four broad
categories, as described below.
Operational Process Chemicals
An operational process chemical is the active chemical added to a process or static
system, which provides functionality when injected in produced fluid, utility system
streams or for treatment. These chemicals types may be present in continuous or batch
discharge streams into the ocean:
• Hydrate inhibitor
• Oxygen scavenger
• Scale inhibitor
• Biocide
• Antifoam
• Demulsifier
• Reverse Demulsifier
• Hypochlorite
• Boiler Water Treatment
• Water Clarifier
• Acids e.g. Hydrochloric, citric, sulphamic
• Paraffin Inhibitor/Pour Point Depressant
• Hydraulic control fluid (subsea) - Subsea control fluids are used to open or close
wellhead/subsea valves resulting in small volumes of subsea control fluids being
discharged each time a valve is activated.

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Environmental impact assessment of the routine planned waste streams and their
respective chemical constituents is detailed further in Sections 9.9.2 and 9.9.3 and are
not addressed further in this subsection.
Facility Maintenance/Non-Process Chemicals
Facility maintenance chemicals include chemicals which are required for general
maintenance activities on the FLNG facility, marine support vessels and respective
equipment. These may include paints, degreasers, greases, fire-fighting foam,
lubricants and domestic cleaning products. They may also include chemicals required
for speciality tasks, such as laboratory testing and analysis. These non-process
chemicals generally present negligible risk to the environment as they are either not
usually discharged as a result of their use (e.g. paint) or are used intermittently and/or
are typically only ever discharged in small volumes and/or low concentrations (e.g.
domestic cleaning products, washdown cleaners, closed cooling water change out or
fire-fighting foam during testing).
Subsea Operation, IMR and Intervention Activity Chemical Discharges
The majority of the maintenance and intervention activities are non-intrusive visual
inspections undertaken via ROV as the facilities are designed for a minimum of 25
years field life with minimal intervention. However, in the event that the certain subsea
equipment needs maintenance, repair, replacement or well intervention due to failure
or damage for example, the estimated associated discharge types and volumes are
provided in Table 9-38.
Table 9-38: Estimated Chemical Discharge Types and Typical Volumes during Subsea
Operation, IMR and Intervention Activities

Discharge Type Estimated Discharge Per Event

Control module replacement Approximately 4L of HT2 TransAqua Hydraulic Fluid

(or similar)

Choke valve replacement Approximately <1m3 of MEG with residual produced

hydrocarbon per valve replacement

Flow module replacement Approximately <1m3 of MEG with residual produced

hydrocarbon per flow module

Flowline connector replacement Approximately <1m3 of MEG with residual produced

hydrocarbon per connector

Flexible riser connector Approximately 20m3 of MEG with residual produced

replacement hydrocarbon per connector

Riser replacement Approximately 40m3 of MEG with residual produced

hydrocarbon per riser

Light well intervention (Refer to Approximately 3.2 m3 MEG, residual produced

Section 6.4.5-6.4.6) hydrocarbon, freshwater and associated dosing
chemicals discharged from the production trees and
well intervention tooling.

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Discharge Type Estimated Discharge Per Event

Dye used for leak detection and Approximately 5-50L per leak test or monitoring event
environmental monitoring purposes

Cycling of subsea valves1 Approximately 0.01-11L per actuation per valve of HT2
TransAqua Hydraulic Fluid (or similar)

Hotstab activities Approximately 0.5-10L of associated chemical in use

per hotstab

Sulphamic acid (or similar For SCM replacement – Approximately 5m3

alternative) used for marine growth
For general inspection/ROV manipulation –
removal or pipe treatment
Approximately <0.1m3 per inspection point/activity

Grouting, grout bag installation and Approximately 0.2m3 per discharge

grout line flushing

1 – Note cycling of valves and associated discharges is also a routine ongoing activity

A number of other planned liquid discharges may occur during the project life, including
hydraulic fluids from ROVs or other underwater equipment, downline flushing (e.g.
grout and/or hotstab lines during IMR campaigns), lubrication fluids from planned
maintenance of the subsea system, fluids from IMR activities such as coatings repair,
closed cooling water replacements, hydrotest fluids and others from time to time.
These discharges are expected to be for short durations, infrequent and/or relatively
minor in nature and scale and any potential impacts of such discharges are expected to
occur within the area influenced by the larger planned discharges described in this
section and are unlikely to result in impacts to the environment that are not already
assessed within this EP.
It is impractical to forecast exact types and volumes of all required liquid discharges for
potential future activities throughout the facility lifetime and therefore Table 9-38 is
indicative only for the purposes of this impact assessment.

9.9.2 Description and Evaluation of Impacts

Planned liquid discharges to marine waters creates a potential for the localised decline
in water and sediment quality and for biota in those environments to be exposed to
physical characteristics and contaminants at concentrations that may cause acute or
chronic effects.
The identified effect pathway associated with the planned liquid discharges can be
summarised by the following:
• Changes to physical and/or chemical water quality resulting in:
o Impacts to sensitive biological receptors.
Any effects on water quality are expected to be within the surface layers only and have
no effect on or damage to seabed/benthic receptors (refer to Section 9.9.2.2 Biological
Environment for further details).
The magnitude and sensitivity of any impacts on the identified sensitive receptors
varies according to multiple factors, including discharge composition, plume

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dilution/dispersion, bioavailability, duration of exposure and marine species physiology

and behaviour. A detailed description and evaluation of these impacts is provided in the
subsections below. A summary presenting credible interactions associated with the
various liquid discharges is provided in Table 9-39 assessed per environmental
receptor category. Where credible interactions have been identified these have been
discussed in further detail in the subsequent impact assessment sections and are
broken down further into receptor sub-category where relevant. The subsequent impact
assessment also provides justification on why certain receptors, e.g. sediments and
benthic habitats, have been assessed as having no credible interaction and/or where
no environmental damage or effects have been identified for the duration of this EP.
Table 9-39: A matrix summarising credibility of interactions with the identified
environmental receptors from the various planned liquid discharge streams

Drainage (Slops) and

Blowdown and MBP

Ad-Hoc Discharges
Sewage, Greywater
and Food Waste,

Produced Water
Cooling Water

Brine, Boiler

Effluent
Bilge

Water Quality      

Sediment Quality      

Benthic Communities      

Pelagic Communities      

KEFs      

Threatened Ecological Communities      

Ramsar Wetlands      

Commonwealth Marine Area      

WA Mainland Coastline      

Threatened and Migratory Species      

Heritage      

Marine Protected Areas      

Fishing Industry      

Tourism and Recreation      

Defence      

Shipping      

Indonesian Coastline      

Oil and Gas Industry      

 Interaction Assessed as Non-Credible and/or No Environmental Damage or Effects

 Interaction Considered Credible - Discussed Through Relevant Impact Assessment Sections Below

9.9.2.1 Physical Environment

Drainage (Slops) and Bilge Effluent

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Open Drainage (slops) and bilge waste discharges are intermittent discharges which
can result in water quality changes immediately surrounding the discharge point, with
the spatial extent of changes to water quality remaining very localised. It is recognised
that there may be various minor quantities of metal and chemical constituents that may
not be captured as a part of the oil treatment systems associated with the open drains
and bilge systems outlined in Appendix A: Detailed Facility Description and onboard
support vessels. This may result in the discharge of minor quantities of diluted toxicants
into the ocean which may cause localised and temporary reductions in water quality.
Overall, the residual impact of the discharge of open drainage and bilge effluent to
water and sediment quality is considered of slight impact consequence (Magnitude – 1,
Sensitivity – L).
Food Waste, Sewage and Greywater
Discharge of sewage, greywater and food waste into the marine environment may
impact on water quality, including eutrophication, increased turbidity, increased
pathogens (bacteria, viral agents and/or parasites), and increased biological oxygen
demand (BOD), with the associated impacts on marine biota as discussed further in
Section 9.9.2.2 Biological Environment below. These discharges can contain a variety
of substances typically at very low concentrations, including oil/grease, some organic
compounds, detergents, metals, suspended solids, chemicals, personal hygiene
products and pathogens.
Discharges of food waste, sewage and grey water can cause some temporary localised
nutrient enrichment of the surface waters around the discharge point and have the
potential to attract marine fauna that feed on the particulate material. Such low volume
outputs of nutrients relative to the receiving environment presents no environmental
damage or effects to water quality associated with eutrophication, increased BOD
and/or decreased dissolved oxygen concentrations. The BOD of the sewage,
greywater and food waste effluent is unlikely to lead to oxygen depletion of the
receiving waters as highly oxygenated receiving waters will rapidly assist with
oxygenation of the discharge in such a dynamic offshore environment.
At a discharge release depth of >11 m, the positively buoyant sewage and greywater
effluent plumes are typically heavily diluted by the time they reach the surface of the
water column. Therefore, no detectable impacts to marine sediment quality are forecast
for sewage or grey water due to the significant water depth, buoyant nature of the
plumes and highly dispersive and dilutive environment. For food discharges, based on
biodegradability and water depth in the open-ocean currents, the discharges are
expected to be rapidly diluted and dispersed by the open-ocean ambient currents, with
no detectable impacts to marine sediment quality predicted.
In 2008, Woodside conducted monitoring of 10 m3 of sewage discharged at distances
of 50 m, 100 m and 200 m downstream of a platform and at five different water depths
over a period of 24 hrs (Woodside 2008). This monitoring confirmed that discharges of
macerated sewage were rapidly diluted or nutrients rapidly metabolised. No elevations
in water quality monitoring parameters (e.g. total nitrogen, total phosphorous and
selected metals) were recorded above background levels at any station. This
Woodside monitoring scenario is conservative when compared to the Prelude case
because Prelude’s movement around the turret and the sewage discharge point being
near the back of the hull (more turbulent) will lead to more mixing of the sewage
discharged.
The Woodside (2008) study demonstrated that a 10 m3 sewage discharge over 24 hrs
from a stationary source in shallow water, reduced to approximately 1% of its original

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concentration within 50 m of the discharge location. In addition to this, monitoring at

distances 50, 100 and 200 m downstream of the platform and at five different water
depths confirmed that discharges were rapidly diluted or nutrients rapidly metabolised
and no elevations in water quality monitoring parameters (e.g. total nitrogen, total
phosphorous and selected metals) were recorded above background levels at any
station. As sewage discharge from the FLNG facility is ~10 m3/day as well, this study
provides confidence to the residual impact ranking given the deep water and highly
dispersive offshore environment where the Operational Area is located.

Given the volume and properties of the discharged effluent which are highly
biodegradable, low toxicity and low persistence, the rapid dilution in the open ocean
environment, localised impact area, and distance from the nearest value (Continental
Slope Demersal Fish Communities ~ 14 km and Browse Island ~40 km away), the
residual impact consequence to water quality is assessed as slight (Magnitude -1,
Sensitivity – L).
Cooling Water
The effect of chlorine and chlorine breakdown products in cooling water discharges
have been the subject of many studies, generally through toxicity testing. Chlorine is a
strong oxidant and following discharge and dilution, the residual (free) chlorine quickly
reacts with inorganic constituents such as sodium, iron (II), nitrite and sulphide to
produce chlorides (such as NaCl). The potential impacts of chlorine on the biological
environment are discussed further in Section 9.9.2.2 Biological Environment.
Chlorine Modelling Outcomes
Initially, 0.2 mg/L free chlorine was set as a target concentration for the CW discharge
from FLNG based on the standard practice in the industry and the APASA 2012
dispersion modelling report prior to the commissioning of the facility. A new study was
commissioned in 2019 by Shell to model the field of effect for CW discharges to align
with observed operational conditions around Prelude FLNG. The RPS (2019b)
modelling approach accounted for the swing weathervaning of the facility relative to
both the compass and water flow past the facility. The study additionally recognised
that movement of the facility, relative to the receiving water would affect dispersion
rates and the dilution efficiencies as the facility most of the time closely aligns with the
current flow. This approach was more realistic than modelling discharge from a fixed
point; however, a stated assumption in the model was that interaction of the hull of the
FLNG with the current did not modify the dispersion of the discharges. The study
modelled a worst case discharge concentration of continuous 0.6 mg/L of free chlorine
from the point of discharge and a no-effect threshold concentration of 0.003 mg/L
under the 95th percentile current speed. The 95th percentile current speed in
combination with relatively conservative dispersion allowances was considered suitably
conservative as the most extreme currents recorded for the area (based on 1 year of
measurements at the site) were observed to be short-lived. This gives the dispersion
plume little time to decay, and is closely related to stormy conditions resulting in higher
dispersion allowances. Under the 99th percentile current (0.82 m/s), the field of effect
extended a further 30% (250 m extension) which is more extreme and considered a
rare occurrence for current speeds in the area.
For the purposes of the impact assessment, discharge concentrations of 0.6 mg/L free
chlorine and temperatures up to the maximum design level were assessed based on
the modelling as the worst-case scenario. The investigation of the cooling water
discharges considered processes occurring at near-field and far-field scales and

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focused on the fate of free chlorine within the streams which included application of a
conservative decay rate due to its highly volatile nature (RPS 2019b).
The 12 discharge points of the cooling water system vary by flow rate, location,
orientation and port size (Table 9-36) and were assessed in a cumulative fashion in the
detailed mixing and dispersion study undertaken. The cooling water discharges are
located sufficiently close so that interaction is likely between a number of the cooling
water plumes much of the time (Figure 9-8 and Figure 9-9).

Figure 9-8: View of cooling water discharge ports P53, P54 (inboard pair), P63 and P64
(outboard pair) that discharge rearwards on the starboard side
The dispersion study (RPS 2019b) indicated a dilution level of 200-fold was required for
the CW discharge plume to reach the field of no effect concentration of 0.003 mg/L.
The collective field of effect (impact area) attributable from all cooling water discharges
occurring simultaneously, was predicted to achieve a 200-fold dilution level at
approximately 180 m from the FLNG hull for the worst-case under the 95th percentile
current speed, assuming relatively calm sea conditions. Furthermore, the results
indicated that the field of effect for any lower current speeds and more energetic sea
conditions should be even shorter due to faster dispersion rates and smaller
displacement of the plume. Proportionally shorter fields of effect should result from
discharge of free chlorine at any concentrations lower than 0.6 mg/L thus, a free
chlorine discharge concentration of 0.6 mg/L or less is deemed safe for operation.

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Figure 9-9: Calculation for the combined distribution of free chlorine in the far-field
accounting for all water discharges under the 95th percentile current. Range rings mark
50 m increments from the stern. The field of effect is illustrated for concentrations >3 ppb
free chlorine. The key shows ppb. The gap between the stern and chlorine distributions
represents the near-field zone.

Temperature Modelling Outcomes

The discharge of cooling water near the ocean surface results in a change of surface
temperature of the waters surrounding the FLNG facility, which may cause alteration of
the physiological processes (especially enzyme-mediated processes) of exposed biota.
These alterations may cause a variety of effects, ranging from behavioural response

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(including attraction and avoidance behaviour), to minor physiological stress, to

potential mortality for prolonged exposure if temperatures are sufficiently high.
To examine the behaviour of the outfall plumes, two separate modelling studies have
been undertaken to assess the behaviour of cooling water plumes from a temperature
dissipation perspective. These studies are summarised below:
1. Deltares Figure 9-10

Figure 9-10: Excess temperature larger than 3°C (summer scenario, large flow velocity
directed from the outlets)
2. Shell (2019) undertook sensitivity testing using the USEPA supported CORMIX model to assess the
worst case scenario of the cooling water plume behaviour from the largest single port discharge rate
(SW2 – 14,000m3) releasing water at the maximum piping temperature design integrity envelope
upper-bound of 50°C. Although this scenario is highly unlikely, it has been included in this impact
assessment to test the maximum design envelope to gain confidence around the extent of the
theoretically feasible temperature impacts as an absolute worse-case. The model was applied to
determine the dilution profiles, with focus on the near-field effects, and location of excess temperature
under different scenarios considering low and high tidal flow velocities, winter and summer water
temperatures, and low and high wind velocities representative of the expected environmental ranges.
The worst-case scenarios Figure 9-1111). This scenario is highly unlikely though given the cooling
water pipes typically discharge water a

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Figure 9-11: CORMIX visualisation plot for worst-case winter scenario (low wind, low
flow, downstream). The Near-Field Region (NFR) is indicated in purple.

Given the high volatility state and associated high decay rate of free chlorine, rapid
dilution and dispersion and temperature transference in the open offshore deepwater
environment, highly localised impact area (<250 m from the FLNG), and distance from
the nearest values (Continental Slope Demersal Fish Communities ~ 14 km and
Browse Island ~40 km away ), the residual impact consequence to water quality
associated with cooling water is assessed as slight (Magnitude -1, Sensitivity – L).
Sediment Quality
Shell undertook a preliminary solid precipitation study (2020) to analyse the extent of
sediment in the topsides process and precipitates forming following produced water
entrainment in seawater following discharge. The data points for the experimental
study were gathered from Prelude’s LIMS laboratory database, online analyser
production data and past project data. Inorganic scale formation was assessed using
OLI Studio 9.1 modelling software. Hypochlorite injection was modelled for sodium
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hypochlorite at a 4 ppm dose. The sediment and water quality of cooling water intake is
of sea borne origin as the water is directly drawn up from the sea via the seawater
lifting system. For details on sea water quality refer to Physical Environment Section
7.1.4.
It is known that hypochlorite injection in the cooling water can induce seawater scaling
of calcium carbonate and magnesium hydroxide due to a change in pH levels. The
FLNG seawater system has a scaling tendency of >1 indicating that calcium carbonate
(calcite) can be formed. In the case of seawater treated with hypochlorite the scale is
formed within the ECU and hypochlorite distribution system before mixing with the
ocean as a result of discharging. The model in Figure 9-12 shows the mixing of
hypochlorite dosed seawater back into the marine environment. However, it should be
noted that the FLNG is still in early operational stages and yet to reach steady state.

Figure 9-12: Hypochlorite dosed seawater discharge

CW Residual Chlorine Discharge Limit

Sodium Hypochlorite is used in the cooling system to control biofouling, and is
expected to readily dissociate and breakdown once discharged. The CW on the FLNG
is dosed with hypochlorite; once through the system and discharged, the concentration
of free chlorine will not be more than 0.6 mg/l. In all scenarios, the modelled
concentrations were below the no-effect threshold concentration of 0.003 ppm at 180 m
distance from the discharge point.
An investigation into a power trip on Prelude in February 2020 which resulted in a
shutdown of production on the facility, found a key cause of the trip being fouling in the
sea water heat exchanger system. A subsequent investigation into the marine fouling
of the seawater systems on Prelude revealed that the environment limit that was in
place at the time, to not exceed a 0.2mg/l residual chlorine limit on an instantaneous
basis was found to be one of the primary causes for underdosing of the system which
led to the power trip. The analysis of the field data indicated the following:
1. The ECU is designed to operate with a fixed throughput and has a very small buffer
capacity (degassing tank) which require injections into the seawater streams to match the
total throughput of the ECU. Therefore, in the cases when the flowrate of one of the
seawater streams is reduced or increased, total injection volume into the other seawater
systems also has to be adjusted to match the overall ECU throughput.

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2. The ECU was being operated on targeted point of 0.1 mg/L in order to maintain a residual
(free) chlorine concentration of or less than 0.2 mg/l at the outfall. However, the
investigation showed that the online analysers at outfalls could not accurately measure the
free chlorine concentrations below 0.12 mg/L. At the time, the analysers were being
operated at lower end of their range, 0.03 – 5 mg/L.
3. This subsequently led the operators to operate the ECU system within an extremely small
operating window and the residual free chlorine concentration of the 12 different discharge
streams, which are supplied by 1 ECU providing hypochlorite, had to be controlled within
this small operating window.
This meant that underdosing was not always detected and allowed marine growth to
develop in the seawater systems. Furthermore, there are many factors that affect the
operating performance of the ECU unit. The amount of hypochlorite generated by the
ECU is dependent on the electrical load on the electrolyser. Calcium carbonate and
magnesium hydroxide scales are by-products of the electrolysis process. These scales
typically precipitate on the electrolyser cells, affecting their efficiency and at times
causing blockages in the distribution system. To maintain a high efficiency, acid
washes are performed to dissolve the scale. Due to this mode of operation, the
electrolysing-efficiency will fluctuate based on the time since last acid wash and will
lead to variations in the injection volumes to some of the injection points. The chlorine
demand also varies over time and is dependent on the chemical composition of the
seawater as well as the amount of biological life.
Given the variables associated with operating this system (analysers detection limits,
scaling of ECU and resulting hypochlorite dosing rates, natural variability in seawater
biological levels) it has not been achievable to consistently operate between the 0.12 –
0.2 ppm limit. Early operation found that target free chlorine levels should be
approximately 0.2 ppm (not limited to 0.2 ppm) in order to ensure appropriate marine
biofouling control within the system. Therefore, given the multiple variables associated
with operating the system, an appropriate instantaneous performance limit for free
chlorine levels has been set at 0.6 ppm, with the aim to operate within 0.12 to 0.43
mg/L limit range. This has been deemed to be an achievable target under all operating
conditions, even considering the multiple variables associated with operating the
system. It also operates the system in line with the original design intent which is
important for the overall integrity of the Prelude FLNG.
Moreover, shock dosing or temporarily elevated target residual free chlorine levels will
be required for periodic maintenance of the system or after shut-down/ ECU reliability
issues, which will see elevated residual chlorine levels after periods of no hypochlorite
injection. These elevated residual chlorine levels from shock dosing will also not be
more than 0.6 mg/l. A minimum flow must be maintained through the ECU to ensure
safe and reliable operation of the system. In the rare occasions when one or more
larger seawater users, such as SW2 and SW4, are not in operation there will be an
excess production of hypochlorite available in the system which will need to be
managed. The throughput of the ECU system cannot be decreased sufficiently to
match the maximum flow capacity of the online seawater system (e.g. SW3). To
manage excess hypochlorite, hypochlorite will be discharged to seachests which are
not operating. Flow to the online seawater system will always be maximised first to
minimise the amount of excess hypochlorite.
In addition, the forward seachest which is used as seawater intake when the firewater
system is required during tests or emergencies is continually dosed with hypochlorite at
low rates to ensure the seachest does not fowl up with biofouling affecting the integrity
of this important safety control. Based on historical operations, this system is dosed

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with between 50-2000ppm of hypochlorite depending on the state of the ECU cells
operating at the time of dosing. This system makes up only a very small percentage of
the overall chlorine demand from all seawater systems on Prelude therefore the
impacts from this discharge are not assessed any further.
Desalination Brine, Boiler Blowdown and MBP Effluent
Desalination brine discharge is estimated to be up to approximately 1100 m3/h. Being
of greater density than seawater, this will sink and disperse rapidly in the deep water
and open oceanic currents. The largest increase of salinity experienced would be
approximately 10% in the immediate vicinity of the discharge point.
There are minor amounts of anions, cations (mostly Na+ and Cl-) and residual
chemicals associated with MBP effluent resulting from the MBP regeneration process.
There will also be residual chemicals additives within the boiler blowdown operational
discharges. The potential differences in pH of MBP effluent neutralisation tank and
boiler blowdown water (pH range estimated at 6-12) compared to background seawater
(pH approximately 8.2) are predicted to resolve very rapidly within a very localised area
due to the highly dilutive open offshore deepwater environment and very good natural
buffering capacity of the ocean which will quickly bring the discharge back to ambient
pH (ANZECC 2000).
The residual impact consequence for water quality as a result of brine, MBP effluent
and boiler blowdown discharges is assessed as slight (Magnitude -1, Sensitivity – L).
No detectable impacts to marine sediment quality are predicted as a result of brine,
boiler blowdown and/or MBP discharges based on the water depth, open ocean
currents and low concentration/toxicity of chemical additives.
Produced Water (PW)
Water Quality
PW will be discharged from the FLNG facility and will contain a range of potential
inherent and added contaminants, which is expected to include salts, hydrocarbons,
metals, phenols, nutrients (e.g. ammonium) and residual production chemicals. Whole
of Effluent Toxicity (WET) testing undertaken in 2019 from the MPPE outfall showed
the PW had a pH range of 5.5 - 6.1. Concentrations of OIW ranged from 7 -12 mg/L
along with trace concentrations of dissolved metals.
It is anticipated that the composition of the PW discharge will vary over time as the
reservoir and production characteristics change with variations in reservoir gas
permeability. PW generation commonly increases over time as gas is depleted from the
reservoir. This may cause the PW flow rates to change, which in turn may cause
intermittent fluctuations in PW volumes to the treatment facility and thereby, affects the
effluent discharged water concentrations (USEPA, 2010). The FLNG facility is still in
early stages of production and produced water consists of condensed water only
without formation water, as such any water quality analysis of the PW will not depict the
characteristics of PW influent and treated water effluent streams in later operation. Any
PW water quality parameter stated in this section should not be used as a benchmark
for future performance testing and impact assessment, as true representation of the
PW effluent quality can only be determined after reaching steady state operations.
Interim testing of the discharged water is undertaken using onboard centrifuges and
online analysers to meet and verify the discharge limit of 30mg/L TPH on average of 24
hours and 42 mg/L TPH instantaneous in the discharge. Furthermore, any off-
specification PW effluent is stopped and diverted back to PW buffer tank for re-

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treatment. This would be measured using the online analyser as a basis and monthly
lab results as a back-up.
Based on operational experience to-date, potential contaminants such as Naturally
Occurring Radioactive Materials (NORMs) and organic acids (e.g. acetic acid) are not
expected to occur in quantities that may result in significant environmental impacts and
are therefore not discussed further.
Hydrocarbons in the PW will consist of both relatively low and high molecular weight
compounds. Dispersion modelling studies carried out in the industry in past have
generally predicted a rapid initial dilution of discharged water by 30- to 100- fold within
the first few tens of metres of the outfall point (Neff et al. 2011). Hydrocarbon solubility
generally decreases with increasing molecular weight, and aromatic hydrocarbons tend
to have increased water solubility compared to non-aromatic hydrocarbons of
equivalent molecular weight (Neff et al. 2011). As such, low molecular weight aromatic
hydrocarbons are typically the most available in PW. The PW sampling performed in
2019 indicates BTEX concentrations to be in the range of 0.01-0.025 mg/l, low-
molecular weight PAHs to be less than 3 mg/l, which include naphthalene,
phenanthrene and dibenzothiophene (NPD) compounds and pyrene. Low molecular
weight hydrocarbons are of particular interest, as these tend to have the greatest
potential for toxicity (Neff et al. 2011). Higher molecular weight compounds are largely
recovered during the production and PW treatment processes onboard the FLNG
facility. However, residual high molecular weight hydrocarbons, such as C10-C40, may
still occur in the PW stream as very fine entrained oil droplets.
The PW testing performed indicated a residual concentration of 10 mg/L for total C10-
C40 components. PAHs are less volatile and soluble than BTEX and have greater
potential to accumulate in the marine environment (Neff et al. 2011). PAHs dissolved in
PW are predominantly low molecular weight and, while toxic, they are not typically
mutagenic nor carcinogenic (although their metabolic by-products may be) (IOGP
2005). Higher molecular weight PAHs are rarely detected in treated PW due to their
low aqueous solubility. These compounds are primarily associated with dispersed oil
droplets which are typically removed by the production process and PW treatment
systems (Neff et al. 2011; Schmeichel 2017). PAHs are generally removed from the
water column through volatilisation to the atmosphere upon reaching the sea surface,
particularly the lower molecular weight fractions (Schmeichel 2017). PAHs can also
degrade in the water column with half-lives ranging from less than a day to several
months, with the more abundant and lower molecular weight compounds being more
degradable (IOGP 2002).
BTEX compounds are the most common hydrocarbon component of PW, however, are
highly volatile and do not persist in the environment. Evaporation and dilution will
rapidly reduce the concentration of BTEX in the receiving environment (Ekins et al.
2005; IOGP 2005; Neff et al. 2011). Other processes such as biodegradation and
photodegradation are expected to further reduce BTEX concentrations in the
environment (Neff et al. 2000). BTEX is known to be toxic to marine organisms and has
been shown to result in developmental defects (Fucik et al. 1995) but does not
significantly bioaccumulate (Neff 2002). As such, potential impacts from the decrease
in water quality due to BTEX are expected be very localised spatially around the FLNG
and more so toward the end of field life operations.
A variety of metals may be present in PW in varying concentrations, some of which
have the potential to cause adverse impacts in the marine environment, while others
are a necessary component to maintain life with some being essential at low quantities,
but potentially toxic at high levels (Khayatzadeh and Abbasi 2010). It should be noted
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that until breakthrough of formation water which is anticipated to be sometime during

year 7-9 following startup (i.e. 2025-2027), inherent reservoir originated levels of
metals within PW are expected to be low, which is evident in the MPPE outfall sample
testing done in 2019 showing heavy metal concentrations to be less than 0.3 mg/l.
Prior to water breakthrough, PW originates primarily from condensation of water vapour
entrained within the produced gas stream which is typically free of metal contaminants
given it originates from a gaseous phase. While concentrations of trace metals in PW
can be greater than those in the ambient marine environment, they are rapidly reduced
through dilution and mixing processes, and other physicochemical reactions to levels
that pose a nil to slight impact consequence to the receiving environment (IOGP 2005).
Azetsu-Scott et al (2007) also found that despite metal concentrations being much
higher in PW than those in the natural seawater, no significant correlation between
toxicity and metal concentrations was observed in the study, indicating that metal
concentrations alone may not be responsible for any observed toxicity.
Mercury levels in the PW to date have been measured at around 2 ppb (wt).
Additionally, mercury from the nearby analogous Brewster and Plover reservoirs is
elemental mercury (Hg), which is relatively unreactive, and has little tendency to
dissolve in water, and readily volatises into the atmosphere (Neff 2002). Conversion of
elemental mercury to methylmercury (MeHg+), with a potential to bioaccumulate and to
be toxic, does not occur in well-oxygenated environments (Neff 2002), such as those in
waters surrounding the FLNG.
A range of process chemicals will be introduced into the hydrocarbon process and may
be subsequently discharged to the sea in residual amounts if they partition into the PW
and are not removed via the available treatment processes. Some of the process
chemicals may be at concentrations that have potential to cause impact or contribute to
the toxicity of the PW, such as biocides (Neff 2002). The ecotoxicological impacts of
process chemicals in PW discharges was comprehensively investigated in a study by
Henderson et al. (1999). The study tested 11 commonly used process chemicals
(including biocides, corrosion inhibitors and demulsifiers) for their acute toxicity to
marine bacterium, both directly in aqueous preparations and following their partitioning
between oil and water phases. The study results indicated that toxicity of the PW was
not significantly altered by the presence of most process chemicals used in typical
concentrations. A review of the study by Schmeichel (2017) notes that process
chemicals make a small contribution to the overall acute toxicity profile of PW
discharges and even chemicals which are classified as highly toxic may not actually
present an acute toxicity risk at dosages representing normal operating conditions. As
such, production chemicals in the PW discharge will not result in more than slight
impact consequence to water quality.
MEG is readily biodegradable in the marine environment in aerobic and anaerobic
conditions through microbial action, with studies showing degradation to < 10% of the
initial concentration occurring with 1 to 21 days (Staples et al. 2001). MEG
concentrations in the PW discharged was tested to be in the range of 6400-6900 mg/L
based on the samples taken from the MPPE outfall in 2019. MEG does not persist in
the environment once discharged and degradation of MEG by microbial action tends to
increase with temperature. Therefore, degradation in the warm tropical seawater at the
discharge location is expected to occur rapidly. Microbial degradation will account for
the fate of almost all MEG discharged. It has been shown to be practically non-toxic
(based on US EPA definitions) in relation to aquatic organisms (Staples et al. 2001)
and is entirely miscible in water and has low potential to combine with lipids and
therefore has very low potential for bioaccumulation (Dobson 2000, Staples et al.

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2001). The Oslo Paris Convention (OSPAR) Commission lists MEG as a substance
considered to Pose Little Or No Risk to the environment (PLONOR).
PW Modelling Studies
The APASA (2012) modelling study was conducted for PW discharge, which aimed to
quantify the field of effect and define threshold concentrations of various constituents in
the PW discharge. Note that the standalone PW assessments presented here do not
factor in any dilutive or compounding influences presented by other liquid discharge
streams that may comingle with the PW following discharge, e.g. cooling water. A liquid
discharges cumulative impact assessment was undertaken as a separate study with
the results presented primarily in Section 9.9.3. The study also did not consider the
presence and influence of the ship’s hull in the current regime and resultant
dilution/dispersion so therefore may be considered as conservative in its approach.
To investigate the effect of the liquid discharges the total mixing zone was determined
and was defined based on the dilution targets set out in the model study. The modelling
results indicate boiler blowdown and desalination brine should dilute sufficiently within
the near-field zone for concentrations to decrease below the no-effect trigger
concentration. Chlorine from the cooling water discharges, TPH, and Trisodium
phosphate from the boiler blowdown would require further dilution due to passive
dispersion in the far-field. The spatial extent of the defined mixing zone is considered to
be 1 km, which is supported by the modelling results predicting 5000 dilutions at a
maximum distance of 1030m from the source required to dilute TPH to the required
levels. This defined total mixing zone comprises of two major phases, the near-field
and far-field mixing zones, in sequence, which are measured from the edge of the
FLNG. Details of the two phases are outlined in sections below.
Along with the 1 km mixing zone boundary, a secondary inner boundary is also
considered at 350 m distance from the edge of the FLNG. This boundary condition will
be applicable for any PW constituent other than the one requiring complete 1 km
distance to meet the PNEC limit, i.e. TPH. There is no pre-existing limit / regulatory
requirement underlining the offshore produced water discharge mix boundary
conditions in Australia. Environmental Quality Management Framework established
under ANZG (2018) requires ALARP demonstration for PEC to not exceed the
concentration that is protective of 95% (typically) or 99% (for sensitive receiving waters
with high conservation value) of species. Other established industrial frameworks, such
as International Association of Oil and Gas Producer (IOGP) recognises the taking of a
risk based approach depending on the ecosystem, exposure levels outside the mixing
zone.

The PW is discharged via a single vertical pipe mounted on the side of the FLNG and
near to the bow (49 m from the turret along the centreline) therefore, the allowable
effect area for PW discharge was judged to be 99 m wide. provides a graphical
summarisation of the maximum effect distance rule for the PW discharge.

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Figure 9-13: Designation of the allowed effect distances for the PFW. The left panel shows the calculation of
the effect zone, along the central axis of the vessel. The right panel shows a plan view of the circles (around
the turret) described for the PFW discharge (dashed black lines). The blue lines designate effect distances
of 50, 100 and 200 m from these discharge, as marked.

The study considered processes occurring at two different scales: “near-field”

processes generated by the discharges and “far-field” processes generated by the
ambient current field and ocean turbulence. The near-field mixing zone refers to the
region where the plume’s momentum or buoyancy (or both) are the strongest influence
on the dilution process. Therefore, in this near-field mixing zone, the rate of dilution is
controlled by the engineering design of the discharge, including aspects such as the
discharge velocity, discharge buoyancy and orientation. Further away, where the plume
has lost momentum and achieved neutral buoyancy with the ambient water, dispersion
will occur due to turbulent dispersion and entrainment of the ambient water at its
edges. Thus, the local dynamics of the ocean become a dominant influence on the
dilution process in the far-field mixing zone.
The near field plume for PW discharge from the FLNG is dominated by the downward
momentum of the jet and the difference in temperature and salinity between the PW
discharge and the receiving water. The temperature and salinity at the site varies
therefore, to be conservative, the month with the lowest surface temperature (August)
and the largest difference between PW temperature and ambient temperature was
used in the modelling study (temperature 26.8°C and salinity 34.4 ppt at surface). The
discharge for the near-field case was run for the 5%, 50% and 95% current
exceedance scenarios.
The near field modelling study indicated that relatively high levels of dilution would be
achieved through the jet phase and buoyant entrainment phase of the discharge (87 -
187-fold depending upon the prevailing current speed applied).
The far-field modelling assessed the dispersal of the PW plumes beyond the near-field
accounting for the time-varying nature of local currents and assessed the potential for
recirculation of the plume back to the discharge location, in which case the near-field

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concentrations might be increased beyond those indicated in the near-field modelling.

This may be a potential source of episodic increases in concentration in the receiving
waters. A horizontal dispersion rate of 1 m2/s was applied, and a typical value of 0.0001
m2/s was set for the vertical dispersion coefficient with no decay or volatilisation
included.
3-D stochastic far-field modelling of the PW discharge was then completed using the
CHEMMAP model treating the discharge as a moving source incorporating the results
from a long term heading analysis. Five hundred replicate short-term simulations were
completed with metocean conditions randomly sampled from the 39-year hind cast
data set. The far-field study also assessed the potential for recirculation of the plume
back to the discharge location, in which case the near-field concentrations might be
increased beyond those indicated in the near-field modelling. The results are
summarised below:
• About 99% of the time the PW discharge plume would be diluted approximately 100-
fold by the time it travelled 50 m from the discharge location and over 400- fold by the
time it reached 100 m, as shown in Figure 9-14;
• At 200 m from the source, exceedance of the defined thresholds was not predicted for
any of the specified constituents except for TPH; and
• TPH discharged at 30mg/L requires a minimum of 4,286 dilutions to meet the highly
conservative threshold of 0.007mg/L, this was predicted to occur at a maximum of
1,030m from the discharge point during all modelled scenarios as shown in Table 9-40.

Table 9-40: Maximum distances forecast for far field PW dilution levels

Dilution level Maximum distance to reach dilution

level (m)

×5000 1030

×3000 746

×1000 355

In order to assess the risk on ecotoxicological effects from the produced water
discharge WET testing was conducted. WET testing assesses the toxicity risk by direct
testing of PW samples. It provides direct information on potential toxic effect
concentrations while the effluent is evaluated as a whole, incorporating risks from
known and any unknown toxic components. It also accounts for potential additive,
synergistic and/ antagonistic effects. Furthermore, an analysis of the PW Q2 2019
WET sample was performed and evaluated based on the ANZECC (2018)
methodology and a statistical assessment using the Burrlioz software package to
determine the required number of dilutions to meet both the 95% and 99% species
protection levels. The assessment suggested that:
• To achieve 95% species protection, a dilution range of 100-102 fold was required based
on the samples collected; and
• To achieve 99% species protection, a dilution of 204 fold was required based on the
samples collected.

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Thereby, indicating that both 99TH and 95TH species protection criteria is met for PW
discharged constituent concentration dilution within the defined mixing zone. However,
the defined threshold for TPH is a highly conservative and chronic value taken from
ANZECC 2000 (As derived from Tsvetnenko [1998]). Given the conservative
thresholds established for TPH and the conservatism built into the model, it is
reasonable to assume that suitable dilutions would occur >99% of the time within total
1 km mixing zone from the FLNG to meet the 99% species protection level. This is
supported by the modelling results which predicts 5000 dilutions at a maximum
distance of 1030m from the source (refer Table 9-40).

Figure 9-14: Predicted 95th percentile PW dilution (Left) & Predicted 99th percentile PW
dilution (Right) from APASA (2012)
The proposed mixing zone extent is supported by an additional modelling study
undertaken by RPS (2019a) which assessed the PW plume behaviour if PW is dosed
with 20% MEG to assess density effects on the number of dilutions required to meet
the defined threshold of 7 ppb TPH. In this study, the worst-case linear distance
calculated for the end of the effect zone (4300 dilutions required) from any location on
the hull was calculated at 667 m (Figure 9-15) indicating that applying a 1 km mixing
zone for the impact assessment of PW is sufficiently conservative.

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Figure 9-15: Dilution fields calculated for discharge into the wake zone of the FLNG
(strong current, 20% MEG)

For short duration and infrequent periods when discharged TPH levels may be up to
100mg/L (well clean-up) as described in Section 9.9.1.5 Produced Water (PW),
extrapolating the information from Table 9-40, it is reasonable to expect at least 15,000
dilutions will occur within 2000 m of the source. In support of this prediction, literature
reviews undertaken showed that at 500-1000 m of the discharge points, dilution rates
of 1,000 – 100,000 are typical (IOGP 2005; Neff et al., 2011). Therefore, beyond 2000
m, there are predicted to be no exceedances of the adopted 7ppb TPH threshold for
these short term and once-off events per well.
Given the short-term and infrequent elevations associated with well clean-up activities,
within the dispersive offshore marine environment, any impacts are not considered
significant in a local or regional context and are not predicted to alter the residual risk
ranking.
Sediment Quality
The PW discharge will contain a range of potential residual constituents as discussed
in the water quality section above. Since start up Prelude has observed condensed
water production from the subsea wells. Low chlorides are indicative of water as a
result of depressurising natural gas. Early lab samples indicated a low base sediment
and water (BS&W) at the receival high pressure separator, downstream in natural gas
condensate storage tanks and within PW tanks. Inorganic scaling risk has been
determined as low risk with barite as the dominant species on the Prelude FLNG.
When the stream is discharged to the ocean this risk is minimised. The model below

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shows the mix of produced water into seawater.

Figure 9-16: Mix of produced water discharge modelling

Once steady state is reached solids influx in the PW stream is expected to increase.
The preliminary solid precipitation study (2020) concluded that upon reaching steady
state production another study will be undertaken to understand the full extent of PW
discharge impact on the marine environment.
There are several processes by which potential PW residual constituents could
become incorporated into the sediment if conditions were suitably conducive, including:
• Sedimentation of inherent solids in the PW.
o The production process onboard the FLNG will remove most inherent solids from
the PW prior to discharge. Therefore, the mass of solids discharged in the PW is
expected to be very low. The remaining solids will be very fine in size, and hence
will have low settling velocities. Given the water depth at the discharge location (>
230 m), the predicted behaviour of the plume, the discharge depth, and the low
settling velocities, inherent solids will disperse widely and will not result in impacts
to sediment quality surrounding the discharge location within the currency period of
this EP.
• Dissolved contaminants forming precipitates, which settle to the seabed.
o Dissolved constituents (particularly metals) in the PW may form precipitates once
released into the environment due to changes in pH and availability of reactants
(e.g. oxygen, sulphide etc.). Metals commonly encountered at elevated levels in PW
that may form precipitates include barium, iron and manganese (Neff et al. 2011).
Solids formed by precipitation are initially very fine and will have low settling
velocities. As with inherent solids released within the PW, formed precipitates are
unlikely to be deposited near the discharge location and will disperse widely.
Therefore, precipitates will not result in impacts to sediment quality at or
surrounding the discharge location during the currency period of this EP.
• Adsorption of contaminants onto natural suspended solids, which then settle to the
seabed.
o Some of the potential constituents in the PW, such as metals and hydrocarbons,
may also become adsorbed onto the surface of suspended solids present in the
receiving environment. Water quality studies in the project area have shown that
natural suspended sediment levels are low (Shell 2009). This is consistent with the

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low observed rates of natural deposition in the region as per Glenn (2004) which
states that sediments locally derived from the water column are generally very fine
(i.e. silt and clay sized particles). The low natural suspended sediment load
indicates the potential for adsorption of potential contaminants is limited. Due to the
small particle size, the potential for adsorbed contaminants to be deposited at and
concentrated around the discharge location is low; particles with adsorbed
contaminants are expected to be widely dispersed, resulting in no impact to
sediment quality in the surrounding area.

As particles pass through the water column they will be subject to natural dispersion
through oceanographic processes. In the deep waters around the FLNG (>230 m),
Stokes’ Law indicates a settlement time of approximately >600 days for a 70 μm
particle. Therefore, all anticipated particles which will range up to a maximum size of
<70 μm, will not settle locally around the FLNG facility and are likely to be dispersed
throughout the broader Browse Basin. Even once settled, if at all, finer fraction particles
are likely to be transported further afield via resuspension, resulting in secondary
further dispersion until they assimilate into the resident sediments, if at all.
Each of the mechanisms discussed above by which contaminants in the PW may settle
and be incorporated into sediments is considered to result in no environmental damage
or effects on sediment quality around the FLNG facility. This is consistent with
monitoring results for other offshore facilities, which generally show that natural
dispersion processes appear to control the concentrations of potential contaminants
from PW in sediments to slightly above background concentrations and below levels
known to cause deleterious effects (Neff et al. 2011; Barnes et al. 2019). The discharge
volumes of PW are expected to be relatively low for the majority of the production
period, before increasing as the reservoir becomes depleted. Therefore, the period with
the credible potential for sediment quality impact is concentrated at the end of field life
for the Prelude reservoir which is beyond the spatial scale of this EP’s currency period.
Summary
Given the rapid dilution and dispersion in the open offshore deepwater environment,
highly localised impact area, and distance from the nearest high value sensitive
receptor (Continental Slope Demersal Fish Communities ~ 14 km and Browse Island
~40 km away), the residual impact consequence to water quality associated with PW is
assessed as slight (Magnitude -1, Sensitivity – L).
Given the water depth (>230 m), low inherent and ambient solids, low predicted rates
of precipitation, small particle size and highly dispersive environment, the residual
impact consequence to sediments as a result of PW discharge is expected to be no
impact (Magnitude 0, Sensitivity – L). This impact ranking will be reassessed with each
mandatory re-submission of this EP to ensure currency.
Use and Discharge of Ad-Hoc Chemicals
The infrequent release of minor quantities of chemicals and production fluids due to
planned ad hoc discharge activities may result in a localised and temporary reduction
in water quality around the discharge which has the potential to impact on marine fauna
(discussed further in Section 9.9.2.2 Biological Environment). Discharge of small
volumes of these fluids are predicted to disperse and dilute rapidly with the spatial
extent of any impacts likely to be limited to the water column, and very localised around
the discharge point. Therefore, the residual impact consequence is assessed as slight
(Magnitude -1, Sensitivity – L).

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9.9.2.2 Biological Environment

Drainage (Slops) and Bilge Effluent
Discharges of oily water will be treated to <15 ppm (v) in accordance with MARPOL
requirements. The discharge of these effluents have the potential to adversely affect
water quality which may impact some biological receptors in the immediate area
through acute or chronic toxicity. The potential biological impacts of these discharges
are addressed further in the broader PW assessment within this Section and the liquid
discharges cumulative impact assessment in Section 9.9.3. This is given the similarities
in the cause and effect pathways and that impacts are not anticipated to be greater
than those presented in the PW assessment from these smaller volume and infrequent
discharge streams.
Most threatened fauna species potentially exposed to drainage (slops) and bilge
effluent discharges are air breathing vertebrates, which are unlikely to be directly
affected as their skin is relatively impermeable. Given the low concentrations of oil (<15
ppm) no surface expressions is expected and therefore damage to eyes and lungs
from exposure to oil on the sea surface is not anticipated. Overall, the residual impact
of the discharge of treated drainage (slops) and bilge effluent to the biological
environment with the stated controls in place is considered to be of slight impact
consequence (Magnitude – 1, Sensitivity – L).
Food Waste, Sewage and Greywater
Nutrients in sewage greywater and food waste, such as phosphorus and nitrogen can
contribute to eutrophication of receiving waters. However, this is only likely in still, calm,
inland waters, where it can cause algal blooms, which in turn degrades aquatic habitats
by reducing light levels and producing certain toxins, some of which are harmful to
marine life and humans. The low level of nutrient outputs as shown in Table 9-37 are
not expected to result in levels or conditions that could result in excessive algal,
phytoplankton or cyanobacterial growth or associated depletion reduction in oxygen
levels. Sewage and greywater can also contain hazardous pathogens (including faecal
coliform bacteria), intestinal parasites and viral agents that, if released, may cause
contamination to the food chain and/or other marine users. This is further addressed in
Section 9.9.2.3 Socio-Economic Environment, under the socio-economic environment
impact assessment and will not result in environmental damage or effects.
The overboard discharge of sewage and food wastes creates a localised and
temporary increase in particulates on or near the surface waters. This may in turn act
as a food source for scavenging marine fauna and seabirds, whose numbers may
temporarily increase as a result. The ingestion of small (macerated or reduced to
<25mm) particle sizes within the effluent is not anticipated to have an adverse physical
or toxic impact on resident and transient marine fauna, including listed threatened and
migratory species, e.g. cetaceans or whale sharks.
Open marine waters are typically influenced by regional wind and large scale current
patterns resulting in the rapid mixing of surface and near surface waters where
sewage, greywater and food waste discharges will occur. Therefore, nutrients from
these discharges will not accumulate or lead to eutrophication due to the highly
dispersive environment. As such, the receptors with the greatest potential to be
impacted are those in the immediate vicinity of the discharge. Effects on environmental
receptors along the food chain, namely, fish, reptiles, birds and cetaceans are therefore
not expected beyond the immediate vicinity of the discharges.

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Although the Timor Sea is characterised as a low nutrient environment (Brewer et al,
2007), natural seasonal upwelling can result in localised and sporadic high
phytoplankton productivity along the Sahul Shelf including immediately offshore of the
shelf. The estimated daily loading from sewage, grey water and food waste
(Approximately 37 kg/day of TN and 7 kg/day of TP) is considered inconsequential in
comparison to the daily turnover of nutrients in the area.
The rapid consumption of macerated food and sewage waste by scavenging fauna,
combined with physical and microbial breakdown, ensures that any impacts of sewage,
greywater and food waste discharges are short-lived, localised and negligible. There
are no nearby sensitive or high environmental value habitats or biological communities
that are at risk from temporary increases in nutrient levels, particulates and/or
increased numbers of scavenging fauna. The volume of these discharges is small
relative to daily nutrient turnover in the given area of ocean and the associated
assimilative capacity of the receiving offshore environment. Therefore, the
environmental impact associated with the discharge of sewage, greywater and food
waste is considered to be slight (Magnitude -1, Sensitivity – L).
Cooling Water
The effect of chlorine on marine organisms is well known, given its widespread use as
a biocide (Abarnou and Miossec 1992). Sublethal effects of chlorine on marine biota
include growth reduction in some invertebrate larvae (Best et al. 1981), alteration of
membrane permeability, modification of blood composition, and reduction in primary
producer productivity (Best et al. 1981; Abarnou and Miossec 1992). Concentrations of
free chlorine in seawater that can trigger lethal and sub-lethal response have been
shown to vary among different species and are also dependant on water quality, being
affected by:
• pH
• concentrations of ammonia
• negatively charged inorganic compounds
• Various organic compounds.
Guidelines for the maximum discharge concentrations in marine waters have been set
by a number of authorities around the world, which differ widely in both the levels that
are set and the reactants that are considered. ANZECC (2018) does not specify any
set threshold for chlorine or chlorine products in marine water for Australia, citing a lack
of evidence required to set a meaningful limit, but suggests using 3ppb as a Low
Reliability Value (LRV) in association with other appropriate lines of evidence. Although
this 99% species protection level is relatively close to the acute toxicity value for the
most sensitive of the tested species, this was considered sufficiently protective, due to
its short residence time, the narrow difference between acute and chronic toxicity and
the lesser sensitivity of data for other tested species (ANZECC 2018).
The intent of LRVs are to provide guidance in the absence of any higher reliability
guidelines being available and are derived by applying larger application (safety)
factors to the toxicological data to account for the greater uncertainty associated with
the limited database (DWER 2017). The ANZECC LRV for chlorine is therefore
considered as conservative and may not necessarily reflect concentrations above
which toxic effects would occur. ANZECC & ARMCANZ (2000) cautions that LRVs
should not be used as default guideline trigger values, but further states that ‘it is
reasonable to use them in the risk-based decision scheme to determine if conditions at

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the site increase or decrease potential risk’. In other words, it is reasonable to assume
that if ambient concentrations fall below the LRV then there is a low potential of
ecological impact. However, if concentrations are above the LRV, it does not
necessarily mean an impact is a given, rather that further investigation and adaptive
management may be required.
Assessment of water quality guidelines for chlorine from a number of other jurisdictions
have also been provided in Table 9-41 to demonstrate that the proposed trigger level of
3 ppb at the edge of the defined mixing zone is consistent and comparable.

Table 9-41: Guidelines for chlorine concentration in water

Authority Guideline, Limit, or Comments

Trigger (ppb equivalent)

DWER (2017) for Cockburn Sound, 3 Taken directly from the

Western Australia ANZECC (2000) LRV.

British Colombia (Water Protection & 3 Based on average continuous

Sustainability Branch [2018]) (Chronic) exposure.

Canadian Council of Ministers of the 2 This is the freshwater guideline

Environment (CCME) (2008) for this jurisdiction.

USEPA (Chronic) (2019) 7.5 Derived from 24 marine species

in 21 genera. The sensitivity
USEPA (Acute) (2019) 13 results were very similar to that
observed in freshwater species
and fish and invertebrate
species had similar sensitivities.

Toxicity assessments undertaken for specific marine species indicate that a 3 ppb
trigger level affords sufficient protection by a factor of 6-62 times that of the available
chronic NOECs (ANZECC 2018):
• Marine fish: Two species, 48 to 96-hour LC50 128 to 250 µg/L (2 to 8 hours/day
intermittent to continuous dosing). Chronic NOEC (7-day growth), Menidia beryllina, 87
to 186 µg/L.
• Marine crustacean: one species, Mysidiopsis bahia, 96-hour LC50, 73 to 268 µg/L (2 to 8
hours/day intermittent to continuous dosing). Chronic NOEC (7-day reproduction), M.
bahia, 20-87 µg/L.
• The 24-hour LC50 for the marine prawn, Penaeus plebejus, was 180 µg/L.
An additional assessment for chlorine was also undertaken during the development of
this EP to develop a Species Sensitivity Distribution (SSD) curve and associated levels
of species protection utilising the CSIRO hosted Burrlioz statistical analysis software in
accordance with Warne et al. (2018) and CSIRO (2019). The data utilised for the
assessment were the LC50 values listed above for marine species in ANZECC (2018)
as well as appropriate data for marine species obtained from the USEPA Ecotox
database (https://cfpub.epa.gov/ecotox//search.cfm) accessed on 29 July 2019 where
this data passed the screening tests as described in Warne et al. (2018). Data filters
were applied to select the appropriate values to assess through the Burrlioz software
package which included:

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• Retention of data for marine species only

• Removal of all data derived earlier than 1980
• Retention of available data for EC/IC/LC50 tests only
• Utilisation of the geometric mean where data were provided for the same species and
ecotox test methodology/duration
• Selection of the lowest value per species
• Application of an Acute to Chronic Ratio (ACR) of 10 as per the default value
recommended in Warne et al. (2018).
The assessment described above yielded the following results:
• 95% Species Protection Level = 13 ppb
• 99% Species Protection Level = 11 ppb.
Given these values were derived from relatively limited data sets in terms of sample
size, they are not being suggested to replace the ANZECC LRV of 3 ppb as the trigger
level (LRV) but rather are provided as an additional line of evidence to demonstrate
that managing to this concentration is a conservative approach that should afford
sufficient ecological and species protection.
Effects of elevation in seawater temperature may include a range of behavioural
responses in threatened and migratory species such as localised attraction and
avoidance behaviour. There are no BIAs or aggregation areas in proximity to the
cooling water discharges from the Prelude FLNG with the closest BIAs relating to green
turtle foraging/interesting buffer at Browse Island (23 km), whale shark foraging (33 km)
and blue whale migration (78 km) as described in Table 7-7. As a benchmark for this
impact assessment, cooling water discharge predictions were compared to the IFC
(2015) guidelines for water temperature. The guidelines suggests discharges should
not result in a temperature differential of greater than 3°C relative to the ambient
temperature at the edge of a defined mixing zone which suggests a default distance of
100m.
The modelling studies undertaken have indicated that the IFC guidelines will be met
under all seasonal conditions within this defined mixing zone which is appropriate due
to the lack of sensitive receptors within such a small localised area. In addition, given
that cooling water is discharged on a continual basis, free swimming organisms within
the water column are expected to perform avoidance behaviours towards plumes
outside of their tolerable ranges. Therefore, from a temperature only perspective,
cooling water is assessed as having no residual impact consequence (Magnitude 0,
Sensitivity – L).
In terms of vertical distribution of the cooling water plumes in the far-field, given the
significant water depth and positive buoyancy of the plumes, dilution is predicted to be
such that there will no effects on sediments and/or marine biota associated with the
seafloor such as demersal fish or invertebrate assemblages.
Overall, given the highly dispersive nature of the receiving environment, positive
buoyancy of the plumes, the rapid dilution following discharge, that free chlorine does
not persist long in the marine environment and the lack of resident sensitive and/or
high value receptors, cooling water is not expected to result in credible impacts to
higher order organisms such threatened or migratory species that may intersect the
plumes and at worst is assessed as presenting a residual impact consequence of slight
to pelagic communities (Magnitude -1, Sensitivity – L). Anecdotal observational
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evidence from the FLNG indicates there have been no obvious impacts or behavioural
changes to pelagic communities to-date, with marine fauna such as fish, present in the
immediate vicinity of the cooling water discharges with no apparent stress or
behavioural related responses.
Desalination Brine, Boiler Blowdown and MBP Effluent
The potential impacts of desalination brine have been subject to a considerable amount
of study due to the large number of high-volume desalination plants in operation within
Australia. As a result, the potential impacts are well known. Marine organisms exist in
osmotic balance with their ocean and exposure to a rapid change in salinity has the
potential to result in the dehydration of cells, decreasing turgidity with potentially lethal
consequences. Most marine species are able to tolerate short-term fluctuations in the
order of 20% to 30% (Walker and McComb 1990), and it is expected that all resident
and transient species would tolerate any exposure to the slightly increased
(approximately 10% above background) salinity plume caused by the discharged FLNG
brine prior to dilution to ambient levels. Therefore, the impact of incremental salinity
increases within the discharge stream is not considered further as there will be no
related environmental effects or damage.
The chemicals used in all three systems typically have low inherent toxicity, low
residual discharge concentrations and/or the active ingredients are consumed through
the process for which they are utilised. Based on the available chemical ecotox reports
and associated conservative estimated end-of-pipe discharge concentrations, it was
estimated that the required number of dilutions for each discharge stream to reach its
Predicted No Effect Concentration (PNEC), as calculated using the CHARM
methodology (CIN 2017), were approximately:
• Desalination Brine: 1.25 – 240 dilutions required
• Boiler Blowdown: 400 – 839 dilutions required
• MBP Effluent – N/A PNEC could not be calculated due to inability to undertake
meaningful ecotox tests on the associated products given the need to neutralise
samples to undertake such tests. However, both HCl and NaOH are ranked E under the
OCNS grouping system which represents the least hazard potential and therefore any
impacts are considered negligible due to the rapid buffering capacity of the open ocean.
The number of dilutions provided above is considered highly conservative as these
additives are typically ‘consumed’ in the process, with much lower or no residual levels
remaining upon consumption or discharge (HydroBiology 2006). As discussed further
in Section 9.9.3.4 Desalination Brine, MBP Effluent and Boiler Blowdown Discharges,
the required level of dilution for all three streams is predicted to be achieved within 80m
of the FLNG facility under the 95th percentile current regime.
Based on the discussion above, the residual impact as a result of the discharge of
desalination brine, MBP effluent and boiler blowdown are considered to be of slight
impact consequence (Magnitude -1, Sensitivity – L).
Produced Formation Water (PW)
Benthic Communities
Given the water depth that Prelude is moored in, and the analysis conducted on the
discharge streams, there will be no direct interaction of the plume with the benthic
environment. The only potential impact pathway is likely to be via inherent solids,
precipitates or adsorbed particles settling onto the seabed over time. This may include
metallic mercury, chlorides or other unknown contaminants if they have the potential to

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form due to plume interactions or other processes. Due to the considerable water depth
highly dispersive currents, small particulates, low particle concentrations and likely
resuspension and further dispersion of the finer fractions, the time for particulates to
settle will be such that any settlement will likely be spread over a widespread area of
the seabed (10s-100s of km). This will take a considerable amount of time (10s of
years) to accumulate into detectable limits above background, if at all, and levels
attributable to planned discharges will not reach levels that are known to cause
deleterious effects on the benthos.
Therefore, the residual impact consequence of PW discharge on benthic communities
for this revision of the EP is assessed as no impact (Magnitude 0, Sensitivity – L). This
impact assessment and resultant ranking will be revisited upon future mandatory
revisions of the EP.
Pelagic Communities
The decrease in water quality from potential contaminants in the treated PW discharge
stream may result in localised acute impacts to plankton. Research indicates that
zooplankton exposed to low molecular weight hydrocarbons can exhibit acute toxic
effects (Almeda et al. 2013; Jiang et al. 2010) and developmental defects in fish (Fucik
et al. 1995). In particular, PAHs are of concern due to their solubility, toxicity and
relative persistence compared to BTEX. The concentrations and durations of exposure
required to induce such effects on plankton populations will be short-lived and highly
localised due to the rapid dilution and decay of PW constituents, well mixed open
offshore ocean environment and transient nature of planktonic communities.
Pelagic fish attracted to and organisms attached to the FLNG hull structure may be
exposed to low but potentially toxic concentrations of contaminants within the PW
mixing zone. However, some free swimming species are expected to move away from
the area if they are able to detect nuisance concentrations of PW constituents, which
will be localised to the vicinity of the release location.
Fish can also bioaccumulate heavy metals through food and via water, but uptake by
individuals and by different species of fish is dependent on many factors including the
metal’s form (inorganic versus organic), water chemistry and behavioural traits
(feeding, range) of the fish species in the receiving environment. Atchison et al. (1987)
reviewed acute and chronic toxicity of metals relating to a variety of fish species and
found mercury (inorganic and methyl) and copper to be the most toxic. Some heavy
metals, such as mercury are persistent and can bioaccumulate (Nigro and Leonzio
1996), however some fish species may be able to metabolise metals potentially further
reducing the already slight impact profile (Hodson 1988).
Some fish are able to metabolise and excrete hydrocarbons, potentially reducing
physiological effects to fish exposed to PW hydrocarbons (Bakke et al. 2013). For
example, King et al (King et al. 2005) reported hydrocarbon-degrading bacteria in the
liver and bile of fish collected from their study on the North West Shelf (NWS). Bakke et
al. (2013), who reviewed individual, population and ecosystem level biological
responses to PW further concluded that the spatial scale of impact from PW discharge
was insufficient to impact populations of marine organisms.
Initial WET testing was undertaken on treated PW samples collected on 29 April and
6 May 2019, for details refer PW water quality section above. Although it should be
acknowledged that not all listed process chemicals were being dosed at this time,
regardless the results still provide an indication of the effluent toxicity presented by the
PW originating from the reservoir. This provides a high level of confidence around the

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predicted impacts associated with PW discharges. The following toxicity tests were
undertaken for each of the sampling and analysis events:
• 72-hr marine algal growth
• 48-hr oyster larval development
• 1-hr sea urchin fertilisation success
• 72-hr sea urchin larval development
• 48-hr acute copepod survival
• 96-hr acute amphipod survival.
The methods described in Warne et al. (2018) and CSIRO (2019) were applied to the
relevant data to generate SSD curves (Figure 9-17) and associated levels of species
protection utilising the CSIRO hosted Burrlioz statistical analysis software.

Figure 9-17: SSD curves developed from the PW WET testing results from samples
collected from the Prelude FLNG on 29 April (left) and 6 May 2019 (right)

This calculated that 99% species protection was provided by 0.49% PW for the
respective sampling events, i.e. 204 dilutions were required for each of the samples to
protect 99% of species. This required level of dilution is expected to be achieved in the
near-field or very rapidly within the far-field but within 100 m of the discharge point if
utilising the predicted 95th percentile dilution predictions.
A literature review undertaken showed that at 500-1000 m of the discharge points,
dilution rates of 1000 – 100 000 are typical (Neff et al., 2011). This further provides a
high level of confidence that the defined impact threshold (99% species protection) for
PW will be maintained within 1 km of the FLNG greater than 99% of the time. This
recognises that there will be a potential gradient of impact with receptors within this
mixing zone subject to higher concentrations of contaminants closer to the discharge
release point. However, impacts to the identified receptors with be managed to ALARP
and acceptable levels through implementation of the identified controls and associated
EPSs.
In summary, exposure of pelagic communities to PW, could result in localised
environmental effects on individual organisms, but with no ecosystem function changes
or chronic level impacts to populations. The impact on pelagic communities is therefore
assessed to be Slight (Magnitude -1, Sensitivity – L).
Threatened and Migratory Species

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As the plume is dynamic and moving constantly depending on the tides, currents,
winds and internal waves, transient biota such as migrating whales or whale sharks,
are unlikely to be exposed to elevated contaminant concentrations for extended
durations. Noting that there are no BIAs or aggregation areas in close proximity to the
Prelude FLNG that may result resulting in sedentary marine fauna behaviour. The
closest BIAs relate to green turtle foraging/interesting buffer at Browse Island (23 km),
whale shark foraging (33 km) and blue whale migration (78 km) as described in Table
7-7.
Most threatened and migratory fauna species with the potential to interact with the PW
plume are air breathing vertebrates, whom are typically not affected as their skin is
relatively impermeable and they breathe air. Indirect impacts, such as altered prey
abundance or ingestion of bioaccumulated toxic compounds is considered to be of no
effect given the localised area predicted to be impacted by PW, the typically temporary
or transitory presence of threatened and migratory fauna species, and the nature and
scale of impacts to the marine ecosystem within the PW discharge plume (i.e. slight
impacts to food sources such as plankton and pelagic fish species).
Given the absence of impacts to higher order marine fauna, limited spatial extent of
water quality impacts (within 1 km from the FLNG), the infrequent and short interaction
duration (i.e. minutes at a time) with the PW plume, and that only a very small
proportion of the migrating/foraging population would intersect the discharge plume if at
all, there are no predicted residual impacts to these receptors (Magnitude 0, Sensitivity
– M).
Use and Discharge of Chemicals in Ad-Hoc Discharges
Chemicals used on the facility could cause impacts for specific biota when released to
the environment depending on the nature and degree of exposure received by a
particular receptor. Given the short-term durations and low frequencies of the
discharges described in this section, any potential effects are likely limited in duration
to a matter of minutes after the release, and confined to a small area in the water
column, and therefore only to a low number of individuals that may intersect the
discharge plumes prior to sufficient dilution. No adverse environmental effects are
expected at a community or habitat level for any species. Many chemicals selected for
use subsea (e.g. control valve fluid) or on the facility are water-soluble. As such,
emphasis is placed on minimising/optimising volumes stored, used and discharged
wherever practicable given the inability to recover these substances once released.
Chemicals present within these discharge streams are predicted to have slight residual
impact consequence at worst (Magnitude – 1, Sensitivity – L) given the typically low
toxicity of chemicals selected through the Shell Chemical Management Process
(Section 10.1.10), distance to sensitive habitats, lack of sensitive receptors and high
inherent rates of dilution and dispersion.
9.9.2.3 Socio-Economic Environment
Impacts on social receptors such as recreational users and commercial operators of
fishing, aquaculture, diving and boating operations, are not predicted nor are credible
due to exclusions in place via the gazetted PSZ, the localised nature of the discharges
and the rapid dispersion and dilution in open offshore waters.
There are no known sensitive receptors to human pathogens in the vicinity of the liquid
discharges location. It is expected that any discharged pathogens will be susceptible to
rapid mortality following exposure to natural levels of UV radiation, oxygen, increased
salinity and natural predation resulting in their reduction and ultimate destruction

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(ANZECC & ARMCANZ 1997). Regardless, transference of human pathogens into

marine fauna resulting in adverse impacts to the organism itself, fishermen or
consumers is not anticipated to occur and/or is not considered a feasible cause and
effect pathway due to the inherent biological and physiological differences in the host
species’ and is therefore considered to present a non-credible impact. There are no
identified recreational uses within the vicinity and therefore any impacts associated with
human primary/secondary contact and the presence of ‘nuisance’ organisms is
considered as non-credible.

9.9.3 Cumulative Impact Assessment

The Prelude FLNG routine planned liquid discharge types and rates are typical of most
manned offshore facilities and the specific characteristics of each are summarised in
Table 9-36. Many design considerations were made in the location of individual
discharge ports and intakes, including potential for interaction and recirculation.
However, as the FLNG facility sits in an open offshore environment where current
conditions may be highly variable and omni-directional, there is a potential for
interaction between some different discharge plume types.
Interactions of the various liquid discharge plumes may be possible under the following
circumstances:
• The discharges are located in sufficient proximity so that the dynamic plumes may
overlap (Refer to Figure 9-7);
• Certain or changing ambient current directions bring the plumes of the same or other
discharges into the discharge path of a plume; and/or
• Severe conditions create substantial turbulence that allows interaction of plumes that
are normally at different depths.
As discussed earlier in Section 9.9.2, detailed impact assessments of the individual
discharge stream types have been undertaken as standalone reviews. However, as the
FLNG includes multiple, proximal located discharges that may comingle following
release (Figure 9-7), a study of the potential for these plumes to interact, and the likely
level of common constituent intersection and associated constituent compounding was
undertaken (RPS 2019b) to inform a cumulative impact assessment. This study
calculated the defined fields of effect (impact area) of wastewater discharges from the
Prelude FLNG, taking account of any co-mingling or cross-contamination potential.
Such fields of effect were calculated as the maximum distance from the FLNG where
concentrations might exceed Predicted No-Effect Concentrations (PNECs) for each
constituent of concern calculated using available ecotoxicity data and applying the CIN
(2017) methodology.
Liquid discharges undergo dilution through multiple processes:
• Turbulence generated by the momentum of the water passing through a restricted port
• Turbulence generated by the discharge jet penetrating the receiving water due to
viscous resistance
• Dispersion occurring as the plume rises or sinks due to relative buoyancy
• Dispersion due to advection and turbulence present in the water column.

The first three processes are dominated by the characteristics of the discharge,
including the flow rate, port size, orientation and water density, relative to the receiving
water, and is complete within relatively short time and space scales. Hence, are

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commonly referred to as “near-field” processes. The fourth process will occur later and
will be dependent upon the levels of mixing energy that are set up by ambient current
and wave action around the discharge location. This fourth process occurs over longer
time and space scales and is commonly referred to as the “far-field” process. PW,
Treated Drainage and Bilge (Slops) Discharges Treated drainage (slops) and bilge
waste flows are expected to be relatively low volume and frequency, and at a much
lower order than PW and cooling water in particular. The PW, drainage (slops) and
bilge waste flows are grouped in this cumulative assessment given that all three
discharge streams are expected to contain oil in water (TPH).
Allowing for the dilutive influence of other discharge plumes (e.g. CW) and cases
where the PW stream angles away from the hull when the discharge location is in the
lee of the hull (when the current is towards the port bow), the adopted threshold is
predicted to be achieved before it departs the lee of the FLNG under the 95th percentile
current regime.
Given the PW discharge is located some distance (>400 m) from the other two
hydrocarbon influenced discharge ports (slops and bilge), any influence of PW stream
on the physical or chemical behaviour of these other discharge plumes is predicted to
have no effect. By this point the PW stream is predicted to have diluted in the order of
thousands of times already which will result in all defined constituent PNECs being
achieved prior to any plume intersection (Refer to Figure 9-18 and Figure 9-19).
Any interaction with or flow past the main cooling water discharges will result in
entrainment within the cooling water plume and accelerated dilution due to increased
energy and turbulence. In the case of interaction with SW2 in particular, where the flow
rate is significant, the PW plume would be completely disrupted and entrained into the
cooling water plume, dramatically increasing the effective dilution of the PW plume as it
undergoes a secondary nearfield phase. Contaminants already at very low
concentration are then further diluted. As indicated in Figure 9-18 and Figure 9-19,
there are no significant TPH compounding effects predicted between the PW and
bilge/drains(slops).
As shown in Figure 9-19, the treated bilge and drainage (slops) discharge plumes are
anticipated to comingle but the resultant plume TPH concentration is predicted to be
diluted to within the defined 7 ppb PNEC within 150 m of the FLNG under the 95th
percentile current regime. Allowing for the 99th percentile current, the field of effect
could extend to 200m from the FLNG facility.

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Figure 9-18: Calculation for the field of effect of TPH in the far-field resulting from the PW
discharge. The field of effect is illustrated for concentrations > 7 ppb TPH. The key
shows ppb. Range rings mark 25 m distances from the source. The red circle indicates
the end of the near-field zone. The green circle indicates the location of the PW
discharge.

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Figure 9-19: Calculation for the field of effect of TPH in the far-field resulting from slops
and bilge discharge occurring with all other discharges. The field of effect is illustrated
for concentrations >7 ppb. The key shows ppb. Range rings mark 50 m distances from
the stern. The gap from the stern represents the length of the near-field zone.

9.9.3.2 Food wastes, sewage and grey water

Discharges will be relatively fresh (less saline) compared with the receiving waters, and
therefore positively buoyant and may reach the surface under weaker current
conditions. As the plumes will be situated in the upper layer of the ocean, there is
potential for the resultant plumes to interact with each other and some of the other
defined liquid discharges. Given the high dilution, low volume and low toxicant
concentrations, it is not anticipated that food, sewage or greywater discharges would
result in any cumulative impacts amongst each other or any other liquid discharge
streams.

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9.9.3.3 Cooling Water

Generally, the weathervane movement of the FLNG with wind and currents is expected
to result in the cooling water flows moving predominantly away from the stern of the
FLNG, and therefore with limited potential for interaction with the PW discharge port.
The cumulative field of effects and achievement of the defined thresholds for all CW
ports is previously discussed in Section 9.9.2.1 Physical Environment and is not
repeated here.
In rare cases where the plume may be flowing towards the PW discharge port, the
dilution over the >390 m distance prior to interaction will be significant. The plume is
likely to be mixing vertically during this flow, and the PW discharge will jet through the
cooling water plume, entraining some of the remnant cooling water plume. This may
provide an opportunity for constituents in each stream to mix. In particular there may be
potential for the formation of chlorides that may precipitate. Chlorine reacts with most
metals to form metal chlorides, and so free chlorine has the potential to interact with
some constituent metals in the PW discharge should the plumes cross paths under
particular current conditions. There is also a possibility of free chlorine reacting with the
dissolved aromatic hydrocarbons in the PW discharge. The complexing of metals such
as cadmium, lead and nickel with chloride compounds can act to increase or decrease
their toxicity to aquatic organisms and the rates of uptake by those organisms, effects
which also depend on temperature and salinity. The formation of metal chloride
complexes is also affected by salinity, with increasing salinity generally leading to both
increased formation and reduced toxicity. Chlorinated aromatic hydrocarbons (such as
chlorobenzene) will tend to adsorb to suspended sediments and other matter, and may
also bioaccumulate in aquatic organisms.
While these chemical complexes are a potentially toxic hazard to marine organisms,
the likelihood of metal chlorides or chlorinated aromatic hydrocarbons being present in
significant concentrations beyond the immediate vicinity of the discharge source is
considered to be non-credible when the initial pollutant concentrations in the respective
discharges and subsequent dilutions prior to interaction are taken into account.
9.9.3.4 Desalination Brine, MBP Effluent and Boiler Blowdown Discharges
As per Section 9.9.2.2 Biological Environment, these discharges are likely to dilute and
disperse rapidly. As the plumes are expected to resolve in the upper layer of the water
column, interaction with other near-surface discharges and plumes may be possible.
However, there will not be any considerable cumulative impacts associated with co-
mingling due to the different additives and physical properties not presenting a feasible
multiplication effect. RPS (2019b) shows that due to dilutive influences from other
larger discharge streams (e.g. cooling water) and low inherent toxicity of any additives,
the defined PNEC thresholds are predicted to be met:
• For boiler blowdown and desalination brine, 108 m and 96 m from the discharge location
respectively and <80 m from the FLNG).
• For MBP effluent <65 m from the FLNG).

9.9.3.5 Subsea Valve Discharges

Given the subsea system is located in deep water and a considerable distance from
the FLNG, valve actuation discharges are not expected to interact with any other
planned discharges and are therefore not considered further from a cumulative impact
perspective.

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Cumulative Liquid Discharges Impact Summary

The RPS (2019b) modelling assessment shows that the potential cumulative impacts of
all liquid discharges released simultaneously are not expected to exceed the predicted
impact footprint of the worst-case discharges when assessed in isolation as described
earlier in Section 9.9.2, i.e. slight impacts will be contained within the 1 km mixing zone
from the FLNG described and assessed for PW as a standalone discharge stream.
Given the open offshore location and absence of particularly sensitive or high-value
marine ecosystems or habitats at the FLNG location and within the Operational Area,
predicted cumulative impacts to water quality are considered slight (Magnitude -1,
Sensitivity - L). Bakke et al. (2013) states that typically no impacts are detected beyond
2 km from offshore facilities around the world noting that the nearest potentially high
environmental value habitats that could potentially be affected in proximity to the FLNG
are:
• Browse Island (approximately 39 km from the Operational Area)
• Echuca Shoal (approximately 61 km from the Operational Area)
• Continental Slope Demersal Fish Communities (approximately 14 km from the
Operational Area).

Conservation values are defined as those elements of the region that are:
• key ecological features (KEF) of the Commonwealth marine area
• species listed under Part 13 of the EPBC Act that live in the Commonwealth marine
area or for which the Commonwealth marine area is necessary for a part of their life
cycle
• protected places including marine reserves, heritage places and historic shipwrecks in
the Commonwealth marine area

The nearest island to Prelude FLNG location is Browse Island, which lies
approximately 39 km to the southeast, and nearest MPA is Kimberley. The AMP
provides protection for two KEFs; an ancient coastline (a unique seafloor feature that
provides areas of enhanced productivity) and continental slope demersal fish
communities, the distance of the said Demersal Fish Community group is estimated to
be 14 km away from Prelude (refer table 7-1). While, the closest site recognised under
the Convention on Wetlands (referred to as Ramsar wetlands) having International
Importance, protected under Part 3 of EPBC Act and are MNES, was approximately
162 km away from Prelude, Ashmore reef national nature reserve.

Within the operational area and ZPI observed fauna groups such as whale sharks,
several cetacean species and marine turtles, are listed as threatened and / or migratory
under the EPBC Act. Threatened species are protected under Part 3 of the EPBC Act
and are MNES, with most relevant being the whale sharks and sea turtles which have
been seen near the facility. The nearest sea turtle BIA of green turtles is the
internesting habitat around Browse Island; this habitat lies approximately 23 km south-
east of the Prelude FLNG facility at the closest point, for detailed summary refer
section 7.2.8. While the whale shark BIA does not overlap the Operational Area, it does
extend through the ZPI, and whale sharks are known to occur within the Operational
Area. However, the exposure time for these species within the effected liquid discharge
mixed area is considered short term and periodic with no long-term impact being
associated. Regardless, due to the complex nature, acute impact can be considered
leading to short lived distress or in the worst case, lead to fatality. These instances are
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taken to be extreme cases since both the species are very wide ranging with no
overlapping BIA and the liquid discharge mixing zone area is not recognised as their
important habitat. Negligible impact is considered due to the widespread range relative
to the mixing zone radius of up to 1 km. Given the localised area of impact, 99%
species protection safe dilutions will be achieved by the boundary. Considering the
distance of the nearest ecological and commonwealth significance site, the PW
discharged constituent will be further diluted providing additional protection layer.
In Australia, chronic ecotoxicity data on local species based on WET testing is used as
a basis for Species Sensitivity Distribution (SSD). For SSD, the hazard concentration
depends on the ecosystem. Exposure levels outside the mixing zone should not
exceed the concentration that is protective of 95% (typically) or 99% (for sensitive
receiving waters with high conservation value) of species (Environmental Quality
Management Framework established under ANZG (2018)). The Browse Basin is
subject to considerable exploration activity and the closest operating facility, Ichthys
LNG, is located approximately 17 km from Prelude FLNG. The dilutions required to
protect 99% of species is considered to maintain a high level of ecological protection at
the boundary of the mixing zone. All constituents achieved 99% species protection
guideline values within the mixing zone of 1km. Routine WET testing as per the Table
10-6 will be completed to validate compliance with the species protection safe dilution
requirements. There have been no further opportunities to analyse PW from the
reservoir to date. Dilutions to reach ANZECC 99% species protection guideline values
are provided where applicable.

9.9.4 Impact Assessment Summary

Table 9-42 lists the highest residual impact consequence rankings of the relevant
environmental receptor groups.

Table 9-42: Liquid Discharges Evaluation of Residual Impacts

Environmental Receptor
Consequence
Sensitivity
Magnitude

Residual
Impact

Evaluation – Planned Impacts

Physical Environment -1 L Slight
Biological Environment -1 L Slight
Socio-economic and Cultural
NA NA NA
Environment

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9.9.5 ALARP Assessment and Environmental Performance Standards

Table 9-43: Drainage (Slops) and Bilge Waste Discharges ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
Elimination Eliminate discharges from FLNG No There are significant costs and HSE risks associated N/A N/A N/A
by storing all open drainage and with storing and transporting onshore all open
bilge effluent to be transported drainage and bilge effluent on the marine support
and treated /disposed onshore. vessels and the FLNG. It is grossly disproportionate
to the environmental impacts of onboard treatment
prior to discharging overboard.
Substitution Alternative technology to oil- No The oil-water separator systems on the FLNG and N/A N/A N/A
water separator system. vessels are standard MARPOL-compliant systems
for management of accidentally-oil contaminated
drainage and bilge in offshore installations and
vessels. On the FLNG there is also an option
available to direct off-specification drainage effluent
through the MPPE system if required.
Engineering FLNG: Monitoring of drainage Yes If the online monitor is not functional, manual 7.1 Drainage effluent will not be Records
and bilge discharges. samples will be taken to facilitate determination of oil discharged via the slops demonstrate no
in water concentration to allow batch discharges to system if 30 mg/L (24 hour exceedances of
occur where the batch concentration is confirmed average) oil in water limit is the 30 mg/L (24
below the limit. Discharges at this level are not exceeded 11. hour average) oil
expected to cause any significant impact to the in water
marine environment given low flow rates and high discharge limit.
dilutions close to the source.
7.2 Bilge effluent will not be Records
discharged if the 15 mg/L oil in demonstrate no
water limit is exceeded. exceedances of

11 Advice from the Recognised Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
If the slops open drainage system cannot meet the the 15 mg/L oil in
discharge limit, the effluent can also be routed to the water discharge
Produced Water Treatment System (MPPE) for limit.
further treatment prior to discharge. The Slops
Tanks can also act as a further separation
mechanism for treating Produced Water which has a
limit to 30 mg/L oil in water over a 24hr average.

Oil in water analysis requirements is defined in

Prelude FLNG Oil in Water Analysis Terminology
and Methodology (HSE_PRE_16227).
Engineering Marine support vessels and Yes The marine assurance system is administered by 7.3 Assurance will be undertaken Assurance
Prelude FLNG Compliance with Shell's Marine team and, amongst other for Prelude FLNG and marine records
Marine Order 91 (International Oil requirements, ensures compliance of contract support vessels, including a
Pollution Prevention [IOPP] vessels with MARPOL and Marine Order 91. This check for valid and in date
certificates). control measure is in accordance with Protection of International Oil Pollution
the Sea (Prevention of Pollution from Ships) Act Prevention (IOPP) certificates
1983 and the relevant AMSA Marine Orders. as required by vessel class
requirements 12.
Administrative Spill kits onboard the FLNG and Yes Storage and use of spill adsorbent and clean-up kits 7.4 Spill kits are available on the Records
and Procedural marine support vessels. are inexpensive and low-maintenance. FLNG and marine support indicating spill
Controls Accumulations of oil, grease and other contaminants vessels to clean up small kits are in place.
will be collected and removed from the decks. accumulations of
contaminants.
Administrative Shell Chemical Management Yes Shell has adopted a chemical selection and approval 7.5 Chemicals selected for use in Records
and Procedural Process. process in accordance with Shell’s chemical accordance with the Shell demonstrating
Controls selection and approval guidelines as indicated in Chemical Management the chemical

12 Advice from the Recognised Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
Shell Chemical Management Process Process to minimise potential selection process
(HSE_GEN_007879) and Shell Global Product environmental risks. outlined in the
Stewardship guidelines to assess chemicals than Chemical
may pose environmental impact via planned Management
discharges. Process have
been followed.
Administrative Shell Chemical Management Yes Following the chemical management process as 7.6 Chemicals that are planned for Records
and Procedural Process. detailed within Section 10.1.10 will minimise the discharge to sea are demonstrating
Controls impact of those chemicals which are used and substitution warning free and the chemical
discharged to ALARP levels. Gold, Silver, D, or E rated selection process
through the OCNS, or are outlined in the
PLONOR (listed by the Chemical
OSPAR Commission), or have Management
a complete ALARP Process have
assessment. been followed.

Table 9-44: Sewage, Grey Water and Food Waste Discharges ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Related ALARP Discussion and EPS # Environmental Measurement
Controls Alternate, Additional or Improved Performance Standard Criteria
Control Measures Considered (EPS)
Elimination On board storage of sewage, No Offers limited environmental benefit, as any N/A N/A N/A
greywater and food wastes for changes to water quality beyond a localised
transport to and disposal at an mixing zone are likely to have no
onshore facility. environmental effect.

Is likely to increase operational costs

associated with additional transits to and

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from port and introduce additional safety and

environmental risks related to increased
transit time and operation of additional
vessels, plant and equipment.
Substitution Use of sewage treatment system to No Offers limited environmental benefit, as the N/A N/A N/A
treat all sewage prior to disposal addition of chemicals (such as flocculants
and defoaming agents) would be required to
treat the effluent. Though some reduction in
area impacted may occur this benefit is
offset against the detrimental addition and
increased cost of refined chemicals.
Therefore, the available environmental
impact reduction is negligible to non-
existent.
Substitution Use of alternative treatment No N/A N/A N/A
• Requires additional cost due to the
technologies
space requirement onboard vessels and
FLNG to enable installation.
• Increases operational costs for
maintenance and staffing due to
performance challenges associated with
these technologies (e.g. clogging of
membranes/screens). Also increases
potential exposure of the workforce to
pathogens associated with these waste
streams.

Engineering FLNG: Food waste will be reduced Yes Food wastes are macerated to less than 7.7 Food macerator is Maintenance Records
to <25mm particle size prior to 25mm diameter prior to discharge within 500 maintained in accordance
discharge to sea m of the FLNG. with the MMS to reduce food
waste to < 25 mm particle
size prior to discharge to sea.
Engineering FLNG: Vacuum Toilet System Yes The vacuum toilet system reduces the 7.8 Vacuum toilet system is Maintenance Records
particle size to aid in the rapid dispersion maintained in accordance
and biodegradation of this waste stream. with the MMS to reduce

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sewage particle prior to

discharge to sea 13.
Engineering Further treatment e.g. disinfection of No There are no known sensitive receptors to N/A N/A N/A
the waste-stream prior to discharge human pathogens in the vicinity of the
discharge location that may be impacted
therefore disinfection of the waste stream is
not considered to provide a reduction in the
impact. Additionally, not dosing the waste
stream with a disinfectant such as chlorine
will avoid potential cumulative impacts with
other chlorine dosed streams such as
cooling water.

Furthermore, the consumption of disinfection

chemicals, the resources consumed to
transport the chemicals, and the risk of
excess chlorine being released into the sea
outweighs the negligible environmental
benefits of disinfecting treated sewage
effluent prior to discharge.
Engineering Marine support vessels and Prelude Yes This control measure is in accordance with 7.9 Assurance will be undertaken Assurance records
FLNG Compliance with Marine Protection of the Sea (Prevention of for Prelude FLNG and
Order 96 (International Sewage Pollution from Ships) Act 1983 and the marine support vessels to
Pollution Prevention [ISPP] relevant AMSA Marine Orders. check for valid and in date
certificates) as relevant to vessel International Sewage
class, size and type. Pollution Prevention (ISPP)
Certificates (or equivalent
voluntary statement of
compliance audits where
relevant) , as required by
vessel class requirements 14.

13 Advice from the Recognised Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.
14 Advice from the Recognised Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.

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Administrative Required marine support vessels Yes Each required vessel has its own Garbage 7.10 Marine support vessels (to Garbage Management
and Procedural and Prelude FLNG will maintain a Management Plan/Procedure (or equivalent) which MARPOL Annex V / Plan (or equivalent) is
Controls Garbage Management Plan (or to manage wastes generated and stored Marine Order 95 applies) sighted onboard marine
equivalent) as required by vessel onboard. All wastes that are not permitted have a current Garbage support vessels and are
class, size and type. for discharge are sent ashore for reuse, Management Plan (or maintained up to date.
treatment, recycling and/or disposal as equivalent) 15.
appropriate. This control measure is in
accordance with Protection of the Sea
(Prevention of Pollution from Ships) Act
1983 and AMSA Marine Order 95.
The Recognised Organisation will be
engaged to check on application of this
requirement to Prelude FLNG. Advice from
the Recognised Organisation will be
followed.

15 Advice from the Recognised Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.

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Table 9-45: Cooling Water Discharges ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
Elimination N/A N/A Cooling is required for the FLNG facility from a N/A N/A N/A
safety and technical integrity perspective as part of
the hydrocarbon production process and associated
utilities for personnel. As such, cooling water
discharge cannot be avoided. Collecting, storing,
and transporting all CW discharges to shore is not a
reasonably practicable alternative, due to technical,
financial, and health and safety costs.
Substitution Use of air-cooling instead of No Although air cooling is a technology tested for most N/A N/A N/A
cooling water onshore LNG facilities, water cooling is assessed as
more efficient for the offshore FLNG facility. Air-
cooling would require additional energy (fuel gas
burnt) and equipment which will not fit on the FLNG
from a structural perspective. The discharge of
recycled seawater poses minimal environmental
impact vs. burning more fossil fuels. The use of air
for cooling also doesn’t completely eliminate the
requirement for seawater discharges.
Substitution Use alternatives to hypochlorite No Hypochlorite is produced on the platform from N/A N/A N/A
seawater via the seawater intakes and is used to
prevent biofouling to ensure the continued
operability and integrity of the seawater system.
Other chemicals were considered during the design
phase of the Project but ruled out for technical,
commercial, logistical and safety risk associated
with transporting, handling and storing the quantity
of chemicals required. This transporting, storing and
handling risk is grossly disproportionate to the
negligible environmental gain of substituting the
hypochlorite discharge for a different chemical.

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
Hypochlorite is be readily generated from seawater
which eliminates this risk.
Substitution Use of alternative systems for No Copper-chlorine system: This process utilises N/A N/A N/A
biofouling control sodium hypochlorite (generated as for
electrochlorination) with the toxicity to fouling
organisms boosted by copper ions generated in a
dosing chamber from sacrificial copper electrodes.
The copper and chlorine act on the cell membranes
of the fouling organisms. Due to the synergy of their
action, dosage requirements are significantly
reduced (approximately 5 ppb copper and 50 ppb
hypochlorite). Levels of copper from anti-biofouling
systems have been measured by the US Uniform
National Discharge Standards (UNDS) Program
(US EPA [1999]). Their research has shown that the
concentration of copper discharged from anti-
biofouling systems is between 0.52 and 0.69 ppb
which is above the ANZECC (2018) DGV for copper
which may introduce additional environmental risk in
isolation or cumulatively with chlorine as an additive
effect.

Copper-aluminium-chlorine system: This process is

similar to the copper-chlorine process. The major
difference is that the seawater is passed through an
ion vessel that uses an impressed current method
to selectively dissolve copper and aluminium. This
is again mixed with sodium hypochlorite prior to
dosing the system. So, although the concentration
of residual chlorine could be reduced by the use of
copper-chlorine or copper-aluminium-chlorine
systems, there is potentially no environmental

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
benefit gained as it introduces additional
contaminants that are toxic.
Engineering Chlorine neutralisation No Dechlorination is the process of removing residual N/A N/A N/A
(Dechlorination) (free) chlorine from disinfected wastewater prior to
discharge into the environment. This process
reduces the effect of potentially toxic disinfection by-
products by removing the free/residual chlorine
remaining after chlorination. Further engineering
changes to provide additional treatment prior to the
final discharge, would require additional equipment,
imposing significant additional space and weight
requirements, which are not available on the FLNG
from a structural perspective. Furthermore, with
major financial costs, for negligible environmental
benefit at this location given the slight residual
environmental impact presented by the resultant
plume. Treatment of the CW prior to discharge
introduces additional safety risk associated with
transporting, handling and storing the quantity of de-
chlorination chemicals required which is grossly
disproportionate to the negligible environment
benefit that may be gained.
Engineering Chlorine Adsorption No Carbon adsorption is usually implemented when N/A N/A N/A
total dechlorination is desired. Carbon adsorption
can be an effective dechlorination method, but is
impractical on an FLNG scale whereby numerous
carbon filters would be required to treat a
throughput of ~80,000m3/hr. Not only will this be
impractical from a space / structural perspective on
the FLNG, filtering seawater (which contain salts
and impurities) would constantly block the filters,
requiring frequent change outs and generation of
additional waste.

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Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)

Furthermore, this option introduces capital, ongoing

costs and waste grossly disproportionate to the
negligible environmental gain of further reducing
chlorine concentrations in the CW streams.
Engineering Additional residence time and/or No Further engineering changes to provide additional N/A N/A N/A
treatment prior to discharge treatment and/or storage prior to the final discharge,
would require additional equipment, imposing
significant additional space and weight
requirements. Based on the residence time required
in a vessel, with the throughput of ~80,000m3/hr, a
vessel of 320,000m3 (greater than the volume of all
of Prelude’s 6 LNG Tanks) is required on which is
not feasible to retrofit onto the FLNG for negligible
environmental benefit at this location given the
predicted impact footprint is already small and very
localised.
Engineering Supply of colder seawater Yes At a depth of 150 m, the sea water supply for SW2 N/A N/A - The design features of N/A
sourced from 150m water and is nearly constant at a temperature of 21-22°C the CW system were
use as a cooling medium for the resulting in a lower temperature delta for discharges selected, installed and
main process cooling from this system relative to ambient seawater commissioned at the time
requirements. temperature compared to the scenario of warmer this EP commenced, and are
CW being drawn from nearer the surface. Taking therefore not described in
this quantity of seawater 150m below surface rather further detail here as an EPS.
than at surface is novel for FLNG from a design,
construction and installation perspective and
enhances the energy efficiency of the facility (i.e.
reduction in the GHG emissions footprint, refer to
Section 8.12).
Engineering Electro-Chlorination System Yes The ECU is maintained to ensure the chemical 7.11 The ECU is maintained in Maintenance
(ECU) dosing of the cooling water system is undertaken in accordance with the MMS to Records
minimise the risk of system

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
a controlled manner to optimise dosage to the failures such as line
amount required to achieve treatment efficiency. blockages.

This will include flushing lines as part of ECU

shutdown operations. A trial of line flushing as part
of an ECU shutdown operation was completed on
25 Aug 2019 to prevent the build-up of hypochlorite
in the system and prevent blockages. The
associated re-start on 4 Sep 2019 showed no
exceedances as part of the restart sequence. This
practice will be carried forward to future ECU
shutdown operations and documented in the
Seawater Fouling Inhibition Shutdown for
Maintenance Procedure.
Engineering Online chlorine analysers Yes Online chlorine analysers are maintained to ensure 7.12 Seawater outfall online Maintenance
planned maintenance availability and measurement accuracy is within chlorine analysers are Records including
acceptable tolerance limits.. maintained in accordance validation, lab
If the zero on zero solution is greater than +/- 0.05 with the MMS and where readings and
mg/L the online analyser is re-zeroed. If the required adjusted in calibration
difference between the lab portable and online accordance with required records.
analyser is greater than 0.05 mg/L then the online tolerances and corrective
analyser is recalibrated. actions

Engineering Online Chlorine analyser alarm Yes As per the Alarm Management Manual, Critical 7.13 Online analysers for the Control logic
system Alarms are red flashing with an audible tone and the seawater outfall free chlorine documentation
response principle is "Immediate emergency concentration will have and monitoring
corrective actions for the operators to perform to get critical alarms set at 0.43mg/l records
the variable back within its Critical Limit as stored in on them, which require
the Variable Table (VT)." response within 15 minutes
For residual chlorine alarms, examples of the VT to address the trending
operator actions may include: exceedance.

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS # Environmental Measurement
Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
1. Confirm shock dosing is not in progress
2. Adjust injection rate if required
3. Verify hypochlorite injection control valve on
SW1/2/3/4 inlet is functioning correctly.
With a desired target bandwidth of 0.12 and 0.43
mg/l under normal operating conditions (which
includes the variations in the systems). High level
alarms will be set at 0.43 mg/l. Setting the critical
alarm at this point will ensure the 0.6 mg/l limit is not
exceeded (EPS 7.14).
Given the complexity of the system and manual
operation of the system by panel operators, a
significant amount of time and effort would be
required to actively manage residual chlorine levels
at the 0.2 mg/l desired target operating point. A
significant project would be required to automate
this system, if it was even deemed to be feasible.
The difference in environmental impact between
residual chlorine discharge being around 0.2 mg/l or
0.43 mg/l is minimal given NOEC concentrations
are reached at 100m - 180m for 0.2 and 0.6 mg/l
modelling results respectively.
Operating within a broader range from 0.12 and
0.43 mg/l allows operators to limit time spent
adjusting the system to meet a single target level.
This issue has been highlighted through operation
of the system under the previous requirement to not
exceed 0.2 mg/l, which has come at a great cost.
Therefore, it is grossly disproportionate to the
environmental benefit gained.
Operator response to critical alarms on the
seawater outfall hypochlorite concentration will

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Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
involve taking measures to reduce the outfall
concentration on the outfall line.
Given the multiple ways in which changes to system
performance can occur within the seawater system,
it is not practicable to create a performance
Given the multiple ways in which changes to system
performance can occur within the seawater system,
it is not practicable to create a performance
standard which will ensure the chlorine levels return
to levels below the alarm limit in a defined period of
time such as 15 minutes. However, it is Shell’s
intent to strive for this to occur within this period of
time.
The likely response to an exceedance of the critical
alarm will be a reduction in rates through the ECU,
which should result in a reduction in chlorine
discharge concentrations in a matter of minutes
from executing the action.
Engineering Inlet hypochlorite injection No A change in control philosophy based on a fixed N/A N/A N/A
concentration control target hypochlorite injection concentration was
considered. However, due to fluctuating efficiency of
the ECU, mostly attributed to acid washing, would
result in providing a fluctuating ECU outlet stream.
Furthermore, the chlorine demand is dependent on
the chemical composition of the seawater and the
amount of biological life, both of which are affected
by multiple factors requiring varying chlorine
demand over time. It is highly unlikely to achieve a
constant residual chlorine concentration at the
outfall discharge point. To ensure a positive range
of free residual chlorine concentration at any given
time, a relatively high injection concentration would

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Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
have to be applied, which will result in higher
concentration of chlorine in discharged effluent.
Thus, to ensure a constant injection concentration,
analyser equipment would have to be retrofitted on
the facility, downstream of the ECU.
Engineering Decrease ECU throughput to No A minimum flow must be maintained through the N/A N/A N/A
manage excess hypochlorite ECU to ensure safe and reliable operation of the
system. In the rare occasions when one or more
larger seawater users, such as SW2 and SW4, are
not in operation there will be an excess production
of hypochlorite available in the system which will
need to be managed. The throughput of the ECU
system cannot be decreased sufficiently to match
the maximum flow capacity of the online seawater
system (e.g. SW3). To manage excess
hypochlorite, hypochlorite will be discharged to
seachests which are not operating. Flow to the
online seawater system will always be maximised
first to minimise the amount of excess hypochlorite.
Engineering Control and minimise use of Yes Shock dosing is not anticipated to be used regularly 7.14 Shock dosing in the seawater Pi records of
shock dosing and associated for the Prelude seawater system. However, during system will not exceed 1 hour chlorine
residual free chlorine outfall from certain circumstances such as following extended per 24 hours and shock discharge
the seawater system shutdowns or known biofouling building during dosing will not exceed an concentration
normal operations, there may be a need for shock instantaneous limit of 0.6
dosing to help manage the ongoing control of mg/L.
biofouling within the seawater system. During
normal operations of the seawater system, shock 7.15 Shock dosing will only be Pi records of
dosing would only be considered when normal initiated when biofouling is differential
targeted dosing rates are found to be still resulting likely or known to be pressure
in an increase in the differential pressure in the heat increasing within the
exchangers which is symptomatic of fouling in the seawater system under
heat exchangers. Planned and unplanned shutdown or normal seawater
shutdowns of the seawater systems is a very

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Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
infrequent event and would normally not be system operating
expected to occur more than once or twice per year. circumstances.
Administrative Prelude FLNG Liquid Discharge Yes Monitoring of cooling water and adaptive 7.16 Conduct online monitoring or Monitoring
and Procedural Monitoring and Management management will be undertaken to ensure that the manual sampling (once per records
Controls Procedure chlorine concentration targets and limits are met or 24 hours providing access is
exceedances are appropriately managed. safe for sampling and
Surveillance monitoring of environmental discharge analysis) to confirm chlorine
limits with pre-determined troubleshooting actions discharge does not exceed
will help reduce the frequency and duration of any an instantaneous limit of
exceedances. 0.6 mg/L (calculated per
Based on operational experience and investigation discharge port).
studies on biofouling issues in the sea water heat
exchanger, the free residual chlorine discharge limit
was revised to 0.6 mg/L instantaneous.
The limit is revised to avoid recurrence of biofouling
issue therefore, requiring increased hypochlorite
dosing of the seawater system.
Administrative Decreasing the chlorine dosing No The hypochlorite dosing range and subsequent N/A N/A N/A
and Procedural level of the CW residual chlorine discharge typical concentration
Controls target of 0.2 mg/L with routine shock dosing of up to
0.6ppm is selected to ensure the chlorine
concentration is sufficient to prevent biofouling
throughout the seawater system. Decreasing the
dosing concentration can potentially allow biofouling
to proliferate in the seawater system. This can
compromise the integrity and functionality of the
water systems, leading to significant technical
issues, and increased risk of loss of hydrocarbon
containment scenarios, with intolerable safety risks,
as well as increased potential environmental
release scenarios to the marine environment.
Fouling of the system would also decrease the

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Controls Additional or Improved Control Measures Performance Standard Criteria
Considered (EPS)
energy efficiency of the facility resulting in higher
volumes of GHG production.

Table 9-46: Desalination Brine, MBP and Boiler Blowdown Effluent Discharge ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS Environmental Measurement
Controls Additional or Improved Control Measures # Performance Standard Criteria
Considered (EPS)
Elimination N/A N/A The use of the seawater distillation system and N/A N/A N/A
discharge of boiler blowdown water are common
and accepted practice for vessels and offshore oil
and gas facilities. Offshore activities cannot operate
without fresh water.
Substitution Source all freshwater from No The elimination of the desalination plants to prevent N/A N/A N/A
onshore. the generation of brine water and MBP effluent
would shift the sourcing of water to an onshore
resource to 100%. This would increase demand on
onshore water supply sources (e.g., Darwin or
Broome). It would also result in a high number
vessel movements between the FLNG and port,
resulting in increased personnel hours (and
therefore cost) and increased diesel use (increased
air emissions, waste water discharges [including
brine water] and cost). The increased financial and
environmental cost of this substitute measure is not
commensurate with the low environmental impact of
brine and MBP effluent discharges.

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS Environmental Measurement
Controls Additional or Improved Control Measures # Performance Standard Criteria
Considered (EPS)
Engineering Storing waste effluent onboard No Storing on-board and then transferring it to shore N/A N/A N/A
and transporting for onshore results in increase personnel and environmental
treatment and/or disposal. costs associated with more vessel movements (as
outlined in ‘substitute’), and is not possible given that
the required storage space would not be available
on the FLNG and marine support vessels.
Administrative Shell Chemical Management Yes Shell has adopted a chemical selection and approval 7.5 Chemicals selected for use in Records
and Procedural Process. process in accordance with Shell’s chemical accordance with the Shell demonstrating
Controls selection and approval guidelines as indicated in Chemical Management Process the chemical
Shell Chemical Management Process to minimise potential selection process
(HSE_GEN_007879) and Shell Global Product environmental risks. outlined in the
Stewardship guidelines to assess chemicals than Chemical
may pose environmental impact via planned Management
discharges. Process have
been followed.
Administrative Shell Chemical Management Yes Following the chemical management process as 7.6 Chemicals that are planned for Records
and Procedural Process. detailed within Section 10.1.10 will minimise the discharge to sea are substitution demonstrating
Controls impact of those chemicals which are used and warning free and Gold, Silver, D, the chemical
discharged to ALARP levels. or E rated through the OCNS, or selection process
are PLONOR (listed by the outlined in the
OSPAR Commission), or have a Chemical
complete ALARP assessment. Management
Process have
been followed.
Administrative The boiler blow-down and Yes pH is monitored to measure the efficiency of each 7.17 The boiler blow-down and Pi system records
and Procedural neutralisation tank discharges system and to understand neutralisation neutralisation tank discharges online monitoring
Controls are monitored either by online requirements prior to discharge. are discharged within a pH 6-12 of pH when
analyser or manually for pH. range. These pH analysers are analyser is
maintained in accordance with available or
the MMS laboratory
records

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Table 9-47: PW Discharge ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Adopted? Related ALARP Discussion and Alternate, Additional or EPS # Environmental Performance Measurement
Controls Measure Improved Control Measures Considered Standard (EPS) Criteria
Elimination Re-injection of No Assessment of onboard treatment and overboard disposal versus N/A N/A N/A
produced produced water re-injection was undertaken during the design phase
water. of the project. The assessment supported the use of the onboard
treatment based on the following:
• Produced water reinjection systems require significant additional
capital and operational expenditure with an associated increase
in manning levels.
• Produced water re-injection pumps are a source of high noise
levels in their immediate vicinity and contribute to the overall
noise footprint.
• Lower power demand for the onboard treatment versus
reinjection, therefore lower CO2 emissions.
• For the reinjection option, the produced water treatment facilities
remain the same, in line with overboard disposal, due to
capability of overboard disposal in case the water re-injection
system is down, therefore, there are no equipment reduction
benefits for the re-injection option. According to other facilities
worldwide, re-injection facilities have on average 80%
availability.
• There is potential risk of reservoir souring/scaling due to water
re-injection. The availability of reservoir for re-injection near the
Prelude field without fracking or souring is very limited.
• Only slight residual environmental impact exists from the
onboard treatment and overboard disposal due to high quality
water treatment technology chosen.

Elimination Storage, No All feasible alternatives/options would result in significant additional N/A N/A N/A
treatment and safety, environmental, logistical, operational and financial costs.
disposal These costs would primarily relate to the storage requirements of the
(without well clean-up fluids on the FLNG (as opposed to discharging), prior to
discharging) transport to shore. To enable storage, extra tanks would be required

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Hierarchy of Control Adopted? Related ALARP Discussion and Alternate, Additional or EPS # Environmental Performance Measurement
Controls Measure Improved Control Measures Considered Standard (EPS) Criteria
during well on the FLNG, imposing additional space and weight requirements for
clean up. the well clean-up fluids. Modifying the FLNG to allow temporary
storage of well clean-up fluids, would require significant financial
expenditure.

Transferring the tanks to support vessels would require increased

handling and lifting operations, therefore exposing personnel to
health and safety risks. Additionally, limited onshore facilities are
available to treat, recycle, and/or dispose of such fluids. The potential
environmental benefit is the elimination of the temporary and short-
term changes to water quality around the FLNG and therefore
reducing the potential exposure to pelagic communities (note the
clean-ups are typically one to four days per well). However, this
environmental benefit is considered disproportionate to the
(technical, financial and safety) costs associated with engineering
extra storage or additional treatment facilities requirements on the
FLNG, the additional transfers and the burden of onshore treatment,
at limited facilities.

Therefore, the significant costs of storing, additional treatment and/or

disposing of the fluids are grossly disproportionate to the negligible
environmental gain (of avoiding the short-duration well clean-up
discharges) and are not considered a reasonably practicable
alternative.
Substitution Alternative No The MPPE technology was chosen based on a Best Available N/A N/A N/A
technology to Technology (BAT) assessment during the design phase of the
MPPE system. project. Alternatives to MPPE are steam stripping, adsorption to
activated carbon, advanced filtration, bio-treatment, the use of
hydrocyclones, Induced Gas Floatation (IGF), advanced oxidation or
sent to shore. The MPPE was listed as BAT by the OSPAR
convention for the protection of the marine environment of the North-
East Atlantic (1999) for produced water management on offshore oil
and gas platforms based on the following:

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• Unlike other methods, MPPE technology removes dispersed and

dissolved components effectively
• The effective reclamation procedure of the MPPE material
makes it suitable for removal of high quantities of dispersed and
dissolved hydrocarbon from wastewater but without the
generation of significant waste streams (e.g. spent adsorbents).
• The MPPE technology has an effective regeneration process
such that one column can operate automatically while another
column is regenerating at the same time.
• The MPPE unit operates automatically and operator attention is
limited.

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Engineering MPPE Yes The produced water treatment system is designed and warranted by 7.18 The discharge of the produced Records of TPH
Treatment the vendor to meet a limit of 30 mg/L TPH over 24hr average and 42 water shall have a TPH not in PW
System mg/L TPH instantaneous. Given the slight predicted residual impacts exceeding 30 mg/L (24-hour maintained to
of these concentrations and alignment with international standards, it average) and 42 mg/L verify that the
is an appropriate maximum limit for TPH for Prelude. High availability (instantaneous), except during well concentration of
of the system ensures that incidents of non-compliant discharge are clean-ups. TPH in PW
minimised if not prevented. The change-out of the MPPE columns is meets
included in the maintenance program. Two by 100%-capacity MPPE requirements.
systems are installed on the FLNG (one in extraction, one in
regeneration and two in stand-by) to ensure high availability of the
system. MPPE columns are anticipated to be sent onshore for media
replacement every 2 to 4 years during normal operations.
Furthermore, a buffer tank with ~5400 m3 capacity is also provided in
case of system downtime or if re-treatment of off-specification water
is required. Further redundancy is provided by the option to route the
PW to the Slop system in the event that the MPPE system is not
available.
The system is implemented on two conditions during normal
operations (i.e. not during well clean-up activities); 30 mg/L (24hr
average) and 42 mg/L (instantaneous). The automatic switch-off
within the system allows for the daily average limit to be met. Off-
specification water is redirected inboard when predefined alarm limits
are reached.
Shell will review PW baseline data in 2021 once the PW system has
sufficient operational history. The purpose of this review will be to set
a ‘target 16’ PW OIW discharge concentration, potentially less than
30mg/l, at least during the early years of operation before formation
water breakthrough. The purpose of the target is to internally drive
further improved OIW performance for PW discharge.

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Controls Measure Improved Control Measures Considered Standard (EPS) Criteria

Engineering MPPE Yes Well clean-up: The TPH content of the PW is not to exceed 100mg/L 7.19 During well clean-up activities the Records of TPH
Treatment instantaneous during well clean-ups. The 100 mg/L is the expected produced water shall have a TPH in PW
System worst-case discharge during these clean-up periods given the PW not exceeding 100 mg/L maintained to
water is settled in the buffer tank to remove most dispersed oil from (instantaneous) only where by- verify that the
the PW before treatment discharge overboard. passing the MPPE.is demonstrated concentration of
By-passing the MPPE will only occur in well clean-up events where to be ALARP in reducing the risk of TPH in PW
the risk of damage to the MPPE is deemed unacceptable and not PW discharge. meets
ALARP. Otherwise, the MPPE will be used as in normal operations requirements.
during well clean-up events which will result in treatment levels ALARP note for
consistent with normal operations (i.e. not exceeding 30 mg/l TPH file.
(24 hour average) or 42 mg/l TPH (instantaneous) also.
Engineering Online OIW Yes The online OIW monitor provides information on the performance of 7.20 Validation of the PW online OIW analyser
Analyser: the PW treatment system needed to help ensure discharge limits are analyser will be done in verification
Verification being achieved. Verification, validation and maintenance of the OIW accordance with the MMS. records
and validation analyser ensures that the monitor is operating within an acceptable
of the OIW tolerance of accuracy. Oil in water analysis requirements is defined in
analyser. Prelude FLNG Oil in Water Analysis Terminology and Methodology
(HSE_PRE_16227).
To ensure a discharge limit of 30mg/L TPH (PW) is maintained,
validation of the analyser (PFW) will be done in accordance with the
MMS which is set at monthly. The frequency of the validation was
revised and decreased after 12 months of operation based on
performance and trends generated. When OIW analysers (primary
measurement) are not available due to maintenance reasons, back
up sampling and analysis will be used. Internationally recognised
method such as ASTM, ISO or equivalent for TPH determination will
be used for routine oil in water determination in the lab.
Engineering Manual PW Yes There may be cases when OIW analysers may not be available due 7.21 When discharging PW, if online Sample records
Sampling to maintenance or downtime. Back up manual sampling and analysis analyser is not available; conduct
Procedure will be required in these situations. This will be covered by the manual lab analysis approximately
laboratory sampling and analysis regime defined in Prelude FLNG Oil 6 hourly. Results will be used to
in Water Analysis Terminology and Methodology (HSE_PRE_16227). verify that the PW TPH
An internationally recognised method such as ASTM, ISO or

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Controls Measure Improved Control Measures Considered Standard (EPS) Criteria
equivalent for TPH determination will be used for routine oil in water concentration does not exceed the
determination in the lab. 6 hourly sampling during discharge is defined limits.
deemed representative as well as considered a practicable level to
ensure sampling and analyses personnel are able to fulfil all of their
other roles and responsibilities.

Depending on the result from manual testing, operations will decide

whether to continue operation or to stop discharge and operate the
system in a batch process. The PW will be collected in the buffer
tank, and appropriate number of samples (based on the total volume)
will be collected and analysed to ensure compliance with the limits
before discharging. Note that if batch process is undertaken, no
further sampling will be done during discharge, provided
aforementioned testing is completed and concentrations are deemed
acceptable for discharge.
Administrative Prelude FLNG Yes The procedure provides for implementation of a risk-based adaptive Liquid discharges will be monitored Completed
and Procedural Liquid monitoring and management program for liquid discharges. It relates
7.22 and managed in accordance with records
Controls Discharge to the adaptive monitoring and management framework described in Section 10.4.2 to minimise potential demonstrate
Monitoring and Section 10.4.2. The program comprises several components for PW, environmental risks. implementation
Management including: of the FLNG
Procedure • Topsides monitoring, analysis, and review Liquid
Discharge
• Whole Effluent Toxicity (WET) testing Monitoring and
• Field monitoring Management
Procedure

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Controls Measure Improved Control Measures Considered Standard (EPS) Criteria
• Model prediction verification 7.23 No impact from PW discharges Monitoring,
• Contingency/management actions, as required beyond defined mixing zone 17 modelling,
The program ensures the extent and effect of the PW discharge and boundaries: adaptive
associated contaminants are assessed, and where practicable, management
1. 350 m from the edge of the and/or other
allows adaptive management changes to occur. Prelude FLNG for PW assessments
constituents requiring less than demonstrate
or equal to 1000x dilution level to that 99%
meet 99% species protection species
limit protection is
2. 1000m from the edge of the maintained
Prelude FLNG for PW 99% of the time
constituent requiring between outside of the
1000 - 5000x dilution level to defined overall
meet 99% species protection PW mixing
limit zone.

Administrative Conduct No Shell monitors many aspects of liquid discharge water quality on the N/A N/A N/A
and Procedural annual water Prelude topsides through ongoing online analysers, lab analysis and
Controls quality periodic produced water WET testing and chemical characterisation.
monitoring Using this information, Shell is able to understand very well with
significant conservatism, the likely levels of environmental impacts on
the receiving environment from these discharges. Considering
Prelude is in its early production years between now and 2025, it is
unlikely formation water breakthrough will occur in this time. Until
such time as the formation water breakthrough occurs to the Prelude
FLNG, there is a high degree of certainty that the impacts to water
quality from PFW will be negligible as condensed water which will

17 The mixing zone distance will be measured from the edge of the FLNG. For example, if discharges are moving along the hull from fore to aft, then it would be measured from the aft (rear) of

the FLNG.

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Controls Measure Improved Control Measures Considered Standard (EPS) Criteria
make up almost 100% of the PFW during this time is pure water with
very minor potential hydrocarbon contamination and no other
potential contaminants which are not already known (such as use of
production chemicals in certain circumstances). In addition, given
water quality monitoring is a very time consuming and expensive
activity, it is not appropriate to carry out water quality monitoring in
field more than once during the 5 year life of this EP given the low
risk nature of PFW over this period.
Administrative ‘Mixed Yes The RPS (2019b) modelling assessment shows that the potential 7.22 Liquid discharges will be monitored Completed
and Procedural discharges’ cumulative impacts of all liquid discharges released simultaneously and managed in accordance with records
Controls WET testing are not expected to exceed the predicted impact footprint of the Section 10.4.2 to minimise potential demonstrate
worst-case discharges when assessed in isolation. Given the open environmental risks. implementation
offshore location and absence of particularly sensitive or high-value of the FLNG
marine ecosystems or habitats at the FLNG location and within the Liquid
Operational Area, predicted cumulative impacts to water quality are Discharge
considered slight (Magnitude -1, Sensitivity - L). Monitoring and
The results confirmed that in comparison to the PFW WET testing, Management
that there were no additive or synergistic impacts resulting in Procedure
increased toxicity. Therefore, future WET testing will be undertaken
only on the PFW stream and not on the commingled stream.
However, given the uncertainty associated with modelling, a mixed
discharge WET test will occur to confirm if the modelling is
conservative in line with Table 10-8.

Administrative Shell Chemical Yes Shell has adopted a chemical selection and approval process in 7.5 Chemicals selected for use in Records
and Procedural Management accordance with Shell’s chemical selection and approval guidelines accordance with the Shell Chemical demonstrating
Controls Process. as indicated in Shell Chemical Management Process Management Process to minimise the chemical
(HSE_GEN_007879) and Shell Global Product Stewardship potential environmental risks. selection
guidelines to assess chemicals than may pose environmental impact process
via planned discharges. outlined in the
Chemical
Management

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Controls Measure Improved Control Measures Considered Standard (EPS) Criteria
Process have
been followed.
Administrative Shell Chemical Yes Following the chemical management process as detailed within 7.6 Chemicals that are planned for Records
and Procedural Management Section 10.1.10 will minimise the impact of those chemicals which discharge to sea are substitution demonstrating
Controls Process. are used and discharged to ALARP levels. warning free and Gold, Silver, D, or the chemical
E rated through the OCNS, or are selection
PLONOR (listed by the OSPAR process
Commission), or have a complete outlined in the
ALARP assessment. Chemical
Management
Process have
been followed.
Administrative Maintenance of Yes Documented maintenance program is in place for key PW equipment 7.24 The following PW related Maintenance of
and Procedural PW System on facilities that provides a status on the maintenance of equipment. equipment is maintained as per the PW System
Controls Through ongoing maintenance, the operability of the relevant MMS:
systems and equipment is optimised, reducing the risk of inadequate
PW treatment, monitoring and management. • MPPE columns
• OIW online monitor
Equipment which is critical to maintaining environmental barriers are
• PW Flowmeter.
logged as ECE and are prioritised above all other activities other than
safety critical within the Maintenance prioritisation process.

Table 9-48: Use and Discharge of Ad-Hoc Chemicals ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS Environmental Measurement
Controls Additional or Improved Control Measures # Performance Standard Criteria
Considered (EPS)

Elimination N/A N/A The use of chemicals cannot be eliminated from the N/A N/A N/A
operation, preservation and maintenance of the
FLNG, subsea facilities and support vessels.

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS Environmental Measurement
Controls Additional or Improved Control Measures # Performance Standard Criteria
Considered (EPS)
Substitution Selection of alternate chemical Yes Chemicals planned for discharge have been 7.25 Annual review of chemicals Record of annual
products selected for inclusion based on safety, technical, potentially discharged. production
environmental and commercial performance. The chemical review
purpose of the review is to formally consider the use
of alternative chemicals on an annual basis as part
of the Chemical Management Process (Section
10.1.10). If technically sound, lower cost and lower
environmental risk chemicals can be identified as
possible options for future use, then they will go
through the assessment process and be selected for
use where practicable.
In addition to the annual review, an assessment to
consider alternative chemicals may be triggered
through the adaptive management framework
(Section 10.4.2) as a result of potential changes in
chemical additive profiles (Table 10-) such as a
requirement to increase chemical concentrations or
dosing frequency.
Engineering The subsea facilities are Yes Because of the design, only incidental releases 7.26 Subsea actuation valves are Records from
designed to minimise release of during valve actuations, tie-ins and connections and maintained per MMS MMS
fluids to the environment during subsea interventions are expected.
Engineering Equipment to capture or collect No No practicable engineering controls are available N/A N/A N/A
subsea discharges that are proven to be able to capture or contain
subsea discharges. Designing and installing a
temporary capture system would result in significant
financial costs, with technical uncertainty, grossly
disproportionate to any slight increase in
environmental benefit of preventing small and
infrequent discharges.
Administrative Shell MOC Manual Yes Re-processing or onshore disposal of chemically 7.27 Ad Hoc/Non-routine discharges Records of
and Procedural dosed liquids may be a practicable control measure with chemical additives are completed and
Controls for certain activities or circumstances. This will be assessed and approved through approved MOCs

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS Environmental Measurement
Controls Additional or Improved Control Measures # Performance Standard Criteria
Considered (EPS)
assessed on a case-by-case basis and documented the Shell MOC Manual prior to
accordingly via the MOC process (Section 10.1.9). release.
Any fluid discharges as a result of the activities
would be controlled and minimised through the
system isolations prior to conducting the activity,
thereby limiting the potential discharge volumes to
that which is contained within the targeted and
isolatable section of the containment vessel. The
MOC will detail any isolation steps for the specific
components of the system before activities
commence to reduce resultant discharge volumes to
ALARP.
Administrative Infield water quality monitoring of No Infield water quality monitoring could be used to N/A N/A N/A
and Procedural Ad-Hoc, IMR, installation and/or verify the predicted low risk associated with minor
Controls commissioning based discharges amounts and low frequency of IMR, installation
and/or commissioning fluids planned to be
discharged to the ocean. Monitoring could not be
used to inform adaptive management of these
discharges due to their intermittent/infrequent
occurrence over short periods (typically minutes to
hours). Given the typically low volumes,
concentration and frequencies of the discharges and
the slight associated residual impacts, it is not
considered to be practicable to undertake infield
monitoring as the cost (financial and safety) of
implementation is grossly disproportionate to any
potential further reduction in environmental impact.
Administrative Shell Chemical Management Yes Shell has adopted a chemical selection and approval 7.5 Chemicals selected for use in Records
and Procedural Process. process in accordance with Shell’s chemical accordance with the Shell demonstrating
Controls selection and approval guidelines as indicated in Chemical Management Process the chemical
Shell Chemical Management Process to minimise potential selection process
(HSE_GEN_007879) and Shell Global Product environmental risks. outlined in the
Stewardship guidelines to assess chemicals than Chemical

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Hierarchy of Control Measure Adopted? Related ALARP Discussion and Alternate, EPS Environmental Measurement
Controls Additional or Improved Control Measures # Performance Standard Criteria
Considered (EPS)
may pose environmental impact via planned Management
discharges. Process have
been followed.
Administrative Shell Chemical Management Yes Following the chemical management process as 7.6 Chemicals that are planned for Records
and Procedural Process detailed within Section 10.1.10 will minimise the discharge to sea are substitution demonstrating
Controls impact of those chemicals which are used and warning free and Gold, Silver, D, the chemical
discharged to ALARP levels. or E rated through the OCNS, or selection process
All chemicals planned for discharge will be selected, are PLONOR (listed by the outlined in the
assessed, approved and managed on a case-by- OSPAR Commission), or have a Chemical
case basis in accordance with the Shell Chemical complete ALARP assessment. Management
Management Process to ensure they present the Process have
lowest environmental risk practicable. This process been followed.
is used to demonstrate that the potential impacts of
the chemicals selected are acceptable, ALARP and
not contrary to this EP, as detailed further in Section
10.1.10. Additionally, non-routine, temporary, ad-hoc
and/or contingency chemical discharges associated
with the FLNG, subsea facilities or support vessels
will also be subject to application of the Shell MOC
Manual detailed in Section 10.1.9 as a further
control. This will ensure that additional focus is
provided on such discharges to ensure they are
ALARP, acceptable, optimised and the available
alternatives are adequately considered.

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9.9.6 Acceptability of Impacts

Table 9-49: Acceptability of Impacts – Discharge of Liquid Effluent

Receptor Receptor Sub- Acceptable Level of Are the Acceptability Assessment

Category category Impact Impacts of an
Acceptable
Level?
Physical Water Quality No significant impacts Yes Liquid discharges have the potential to result
Environment to water quality and in reduced water quality in the immediate
quality is maintained so vicinity of the discharge location, however
that biodiversity, discharges will rapidly dilute and disperse in
ecological integrity, the open ocean environment. Modelling
social amenity and studies indicate impacts to water quality are
human health values likely to be highly localised around the
are protected. discharge locations, which is consistent with
industry monitoring studies and demonstrates
high confidence in the assessment that
ecological integrity, social amenity and human
health values will not be significantly
impacted.
Liquid discharges from the FLNG cannot be
avoided. However, the area influenced from
routine operational discharges is expected to
be limited to within 1 km of the liquid
discharge locations. The potential magnitude
of impacts to marine ecosystems is slight.
Given the offshore location and absence of
particularly sensitive marine ecosystems at
the FLNG location and immediate surrounds,
potential impacts within 1 km of the FLNG are
considered acceptable.
Sediment Quality No significant impacts Yes Liquid discharges may result in a slight
to sediment quality and decrease in sediment quality at locations
quality is maintained so around the FLNG over a long timeframe (in
that biodiversity, the order of 10’s of years). For the duration of
ecological integrity, this EP though, elevations of contaminants in
social amenity and sediments surrounding the FLNG will not be
human health values detectable with statistical certainty beyond
are protected. background levels. Therefore, there is high
No significant direct confidence in the assessment that
Biological Benthic Yes biodiversity, ecological integrity, social
Environment communities impacts to bare
sediment benthic amenity and human health values will be
habitats as a result of protected at all times.
the petroleum activities Liquid discharges from the FLNG cannot be
which adversely effects avoided. However, the area influenced from
biological diversity or routine operational discharges is expected to
ecological integrity. be limited to within 1 km of the liquid
discharge locations. The potential magnitude
No direct impacts to of impacts to marine ecosystems is slight.
high-value sensitive Given the offshore location and absence of
benthic communities particularly sensitive marine ecosystems at
(corals, macroalgae, the FLNG location and immediate surrounds,
seagrasses and potential impacts within 1 km of the FLNG are
mangroves) associated considered acceptable.
with named reefs,
banks and shoals.

Pelagic No significant adverse Yes Modelling studies indicate that impacts to

communities effect on pelagic water quality will be localised around the

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Receptor Receptor Sub- Acceptable Level of Are the Acceptability Assessment

Category category Impact Impacts of an
Acceptable
Level?
(Non-Threatened communities, FLNG which is characterised as open offshore
or Migratory) populations, habitats or waters, typical of the offshore Browse Basin.
spatial distribution of a Given the transient nature and absence of
species. important habitat and ecological assemblages
of pelagic species, there is high confidence
that potential impacts to pelagic communities
within a 1 km mixing zone are considered
acceptable given there will not be any
significant adverse effect on pelagic
communities, populations, habitats or spatial
distribution of a species.
Threatened and No significant impacts Yes Most threatened and/or migratory fauna
Migratory to listed Threatened species within the area predicted to be
Species (Endangered and influenced by the planned liquid discharges
Vulnerable) or are air breathing vertebrates, which are
Migratory MNES fauna unlikely to be directly affected as their skin is
populations (Refer to relatively impermeable and they breathe air.
Table 8-1). Hence, direct impacts are not considered
credible. Non-air breathing species are not
anticipated to be present in significant
numbers nor be exposed to levels that may
adversely impact on individuals and therefore
there will be no significant impacts.
Commonwealth No significant impacts Yes Liquid discharges may result in a slight
Marine Area to the Commonwealth decrease in water quality in the immediate
Marine Area (Refer to surrounds of the discharge points and
Table 8-1). sediment quality at locations around the FLNG
over a long timeframe (in the order of 10’s of
years). For the duration of this EP though,
elevations of contaminants in sediments
surrounding the FLNG are not predicted to be
detectable with statistical confidence beyond
background levels and hence remain well
below levels known to cause deleterious
effects. Therefore, there is high confidence in
the assessment that the following relevant
significant impact criteria will not be breached:
• Substantial change in water quality which
may adversely impact on biodiversity,
ecological integrity, social amenity or
human health; or
• Persistent organic chemicals, heavy
metals, or other potentially harmful
chemicals accumulating in the marine
environment such that biodiversity,
ecological integrity, social amenity or
human health may be adversely affected.
Hence, the highly localised impacts predicted
from liquid discharges will not credibly exceed
the MNES significant impact criteria for the
Commonwealth Marine Area as listed in Table
8-1.
Socio- N/A N/A N/A N/A
economic

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Receptor Receptor Sub- Acceptable Level of Are the Acceptability Assessment

Category category Impact Impacts of an
Acceptable
Level?
and Cultural
Environment

The assessment of impacts from liquid discharges determined the residual impact
consequence of slight for physical environment and biological environment (per Table
9-42). As outlined above, the acceptability of the impacts from liquid discharges
associated with the petroleum activity have been considered in the context of:

Principles of ESD
The impacts from liquid discharges are consistent with the principles of ESD based on
the following points:
• The environmental receptors within the Operational Area and defined mixing zones are
not expected to be significantly impacted; and
• The precautionary principle has been applied, and studies (e.g. modelling assessments,
WET testing, literature reviews and statistical data analyses) undertaken where
knowledge gaps were identified.

Relevant Requirements
Management of the impacts from liquid discharges are consistent with relevant
legislative requirements, including:
• Compliance with international maritime conventions, including:
o MARPOL:
 Annex I: regulations for the prevention of pollution by oil
 Annex II: regulations for the control of pollution by noxious liquid substances in
bulk
 Annex III: regulations for the prevention of pollution by harmful substances
carried by sea in packaged form, and
 Annex IV: regulations for the prevention of pollution by sewage from ships
 Annex V: (regulation for the prevention of pollution by garbage from ships).
• Compliance with Australian legislation and requirements, including:
o Navigation Act 2012 and Protection of the Sea (Prevention of Pollution from Ships)
Act 1983:
 Marine Order 91 (Marine pollution prevention – oil)
 Marine Order 93 (Marine pollution prevention – noxious liquid substances)
 Marine Order 94 (Marine pollution prevention – packages harmful substances)
 Marine Order 95 (Marine pollution prevention – garbage)
 Marine Order 96 (Marine pollution prevention – sewage).
• Management of impacts and risks are consistent with policies, strategies, guidelines,
conservation advice, and recovery plans for threatened species (Table 9-50)

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• Implementation of recognised industry standard practice, such as:

o Treatment of PW to the defined limit of 30 mg/L daily average exceeds the
performance recommended by the IFC EHS guidelines for Offshore Oil and Gas
Development (2015) where discharge to sea is allowed if oil and grease content
does not exceed 42 mg/L daily maximum, i.e. mean level for any given day in the
month assessed does not exceed 42 mg/L.
o Treatment of collected drainage bilge water to < 15 mg/L residual oil.
o IFC (2015) standard for water temperature which requires that the effluent should
not result in a temperature increase of greater than 3°C compared to the ambient
temperature at the edge of a defined mixing zone (100 m in this EP).
Matters of National Environmental Significance
Threatened and Migratory Species
The evaluation of liquid discharges impacts indicates significant impacts to threatened
and migratory species will not credibly result from the liquid discharges aspect of the
Prelude petroleum activities.
Alignment of the Prelude petroleum activities with management plans, recovery plans
and conservation advice for threatened and migratory fauna is provided in Table 9-50.
Commonwealth Marine Area
The impacts and risks from the liquid discharges aspect of the Prelude field on the
Commonwealth marine environment will not exceed any of the significant impact
criteria provided in Table 9-50.
Table 9-50: Summary of Alignment of the impacts from the Liquid Discharges Aspect of
the Prelude Petroleum Activities with Relevant Requirements for MNES

Matters of MNES Acceptability Demonstration of Alignment as Relevant to the Project

National Considerations (EPBC
Environmental Management
Significance Plans/Recovery
Plans/Conservation
Advices)
Threatened Significant impact The application of the Shell Chemical Management Process and
and Migratory guidelines for Critically proposed management controls for liquid discharges reduces the
Species Endangered, impact of toxic pollutants being introduced into and/or persisting in
Endangered, Vulnerable the marine environment.
and Migratory species
Table 8-1) An environmental monitoring adaptive management program has
Conservation advice on been developed for liquid discharges as described in Section
Balaenoptera borealis 10.4.1. This program will seek to demonstrate that the actual
(sei whale) (DoE 2015c) levels of recorded impacts for key discharges do not exceed those
which were predicted within the impact assessment presented in
Conservation advice fin
this EP. If recorded impact levels do exceed those described, this
whale (Balaenoptera
would trigger the adaptive management process and assessment
physalus) (DoE 2015d)
under the Shell MOC Manual (Refer to Section 10.1.9)
Recovery plan for marine
turtles in Australia
(Commonwealth of
Australia 2017a)
Conservation advice on
Rhincodon typus (whale
shark) (DoE 2015e)

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Matters of MNES Acceptability Demonstration of Alignment as Relevant to the Project

National Considerations (EPBC
Environmental Management
Significance Plans/Recovery
Plans/Conservation
Advices)
Wetlands of N/A N/A
International
Importance
Commonwealth Significant impact Water quality impacts by planned liquid discharges are expected
Marine Area guidelines for to be limited to within 1 km of the FLNG for all collective discharge
Commonwealth marine streams. Impacts confined within this area are not considered to
environment (Table 7-3) be significant in the context of the significant impact criteria for the
Commonwealth Marine Area given the nature and scale of the
impacts and the characteristics of the local receiving environment
(open offshore waters with regionally well represented soft and
bare sandy sediments). The impact assessment indicates the
impacts associated with the discharge of liquid discharges will not
result in a significant adverse impact on marine ecosystem
functioning/integrity, social amenity or human health.
Shell has sought to reduce potential impacts through the selection
and implementation of the controls and EPSs listed in Section
9.9.5.

External Context
There have been no objections or claims raised by Relevant Persons in preparation of
this EP around the liquid discharges aspect. Shell’s ongoing consultation program will
consider objections and claims made by stakeholders when undertaking further
assessment of impacts.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements.
Acceptability Summary
The assessment of impacts and risks from liquid discharges determined the residual
impacts rankings were slight or lower (Table 9-42). As outlined above, the acceptability
of the impacts have been considered in the context of:
• The established acceptability criteria for the liquid discharges aspect
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
Shell considers residual impacts of slight or lower to be acceptable if they meet
legislative and Shell requirements. The discussion above demonstrates that these
requirements have been met in relation to the liquid discharges aspect.

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The evaluation above in section 9.9.2 and 9.9.3 provide high confidence that any
cumulative liquid discharge impacts within 1 km of the FLNG facility will afford sufficient
and acceptable ecological protection.
Based on the points discussed above, Shell considers the impacts from liquid
discharges associated with the Prelude project to be acceptable.

9.9.7 Environment Performance Outcomes

Environment Performance Outcomes Measurement Criteria

No significant impacts to water quality from liquid Demonstrated implementation of EPSs for
discharges from the Prelude asset. discharge of liquid effluents
No impacts to sediment quality from liquid
discharges from the Prelude asset.
No impact to water quality beyond 1 km from
liquid discharges from the Prelude asset.
No impacts to any KEFs surrounding the Prelude
FLNG.
No injury or mortality of listed Threatened or
Migratory MNES species as a result of discharge
of liquid effluent.
No impacts to coral reefs occurring at Browse
Island or nearby Shoals (Echuca/Heywood).

9.10 Atmospheric Emissions

9.10.1 Aspect Context

Emissions of atmospheric pollutants (e.g. nitrogen oxides, sulphur oxides, carbon
monoxide and particulate matter (PM, PM10 and PM2.5), air toxics which includes mainly
volatile organic compounds (VOCs) (e.g. benzene, toluene, ethylbenzene, xylenes
(BTEX), formaldehyde, etc) and other harmful to human health gases (e.g. hydrogen
sulphide) have the potential to impact local and regional air quality. The list of sources
of such emissions for Prelude FLNG include:
• Combustion of fuel for power generation
• Flaring of hydrocarbon for process safety purposes
• Venting of reservoir carbon dioxide
• General leaks
• Combustion of fuel for transportation purposes – e.g. vessels supporting FLNG
operations.
Sources of internal combustion emissions in the Operational Area include:
• Propulsion and electricity generation engines on marine vessels and helicopter
operations supporting Prelude. Operations support marine vessels include dedicated
supply vessels, infield support vessels/ pilot tugs and campaign specific vessels (e.g.
Inspection, Maintenance and Repair vessels).
• Propulsion and electricity generation engines of LNG, LPG and condensate carriers.

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• The seven (7) 200 MW Marine Boilers on Prelude can operate on fuel gas or diesel. In
normal operations, the boilers run on fuel gas in a 6 + 1 configuration. The boilers
produce high pressure steam which is routed to the process for heating or to the steam
turbine generators (STGs) for power generation and low pressure steam production.
• The three (3) Essential 7.68 MW Essential Marine Diesel Generators (EDGs) providing
power for black start operations and to bring the process to a safe condition during any
major power upsets and supply essential power consumers in the event of a complete
plant shutdown. These are offline during normal operations and has a sparing
philosophy of 2+1.
• The two (2) SOLAS (safety of life at sea) designated Emergency Diesel Generators
(EMGs) (1 x 1250 KW and 1 x 750 KW) which supply electricity to SOLAS critical
equipment (e.g. control and safety systems, navigational aids, fire-fighting pumps, etc.).
These are offline during normal operations.
• Additional sources of internal combustion emissions over the life of the facility and field
include accommodation support vessel(s) during maintenance shutdowns and additional
vessel visits supporting these campaign events. These will occur periodically and result
in additional emissions for the duration of the campaign.
Flaring emissions include the following point sources:
• Warm Wet High-Pressure Flare (FWH Flare) (A-63001)
• Cold Dry High-Pressure Flare (FDH Flare) (A-63002)
• Cold Dry Low-Pressure Flare (FDL Flare) (A-63003)
• Warm Wet Low-Pressure Flare (FWL Flare) (A-63004).
The expected emissions from combustion emission sources are shown in Table 9-51.
Table 9-51: Expected Gaseous Emissions from Combustion Sources of the FLNG
System Flowrate of Discharge Composition of
Discharge
HP steam (marine) boilers A- 1 360 000kg/h N2 – 71.40 %wt
40010~70 (6+1) H2O – 10.86 %wt
(running with fuel gas) O2 – 2.17 %wt
CO2 – 14.46 %wt
NOx – 240mg/Nm3
SOx – NA
PM – 50mg/Nm3
HP steam (marine) boilers A- 266 000kg/h N2 – 73.20 %wt
40010~70 H2O – 5.5 %wt
(for one boiler running with marine CO2 – 19.14 %wt
diesel at 100% load) O2 – 1.95 %wt
NOx – 400mg/Nm3
SO2 – 1500mg/Nm3
PM – 50mg/Nm3
3 Essential generators 7.68 MW 168 000kg/h CO2 – 8.24 %wt
Marine Diesel Generators CH4 – 5.67E-04 %wt
N2O – 7.68E-05 %wt
CO – 4.71E-02 %wt
NOx – 2.14E-01 %wt
SOx – 1.05E-01 %wt
PM – 6.14E-03 %wt
TVOC – 5.43E-03 %wt
1250kW SOLAS designated 9010kg/h NOx – 0.21 % wt
Emergency diesel generator CO2 – 8.00 %wt

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CO – 0.05 %wt
SO2 – 0.10 %wt
PM10 – 0.01 %wt
750kW SOLAS designated 5406kg/h NOx – 0.21 % wt
Emergency diesel generator CO2 – 8.00 %wt
CO – 0.05 %wt
SO2 – 0.10 %wt
PM10 – 0.01 %wt
Note:1. PM = Particulate Matter
2. PM10 / PM2.5 = Particulate Matter with aerodynamic diameter less than 10 microns or 2.5 microns respectively

The additional air emissions from the accommodation vessel and broader turnaround
activities are intermittent, temporary in duration and will comprise a minor and
immaterial addition to the overall air emission profile for the Prelude FLNG and are
therefore not assessed any further in this section.
The environmental basis of design (2000-110-G000-GE00-G00000-HX-7704-
62001_05A_1) for Prelude outlined that vents were designed to meet the
recommendations for Good International Industry Practice (GIIP) for Natural Gas
Processing Plants and the requirements from the Integrated Pollution and Control
(IPPC) Reference Documentation on Best Available Techniques for Mineral Oil and
Gas Refineries. These guidelines require that in all vents the VOC content is
<150mg/Nm3 for a continuous vent and <10g/Nm3 for a non-continuous vent. During
design, the acid gas vent (A63008) had been identified as exceeding the 150mg/Nm3
limit. The design document stated exceeding is acceptable if ALARP.
As a participating organisation to The World Bank Global Gas Flaring Reduction
(GGFR) Partnership, Shell Group has committed to the Zero Routine Flaring by 2030
initiative. Although this initiative is focused on oil producing assets with associated gas,
Shell adopted this philosophy in the environment basis of design applying a ‘no flaring
or venting’ of hydrocarbon streams principle. This principle states that for any source
resulting in more than 1000 tpa of GHG production, no continuous feed to flare or vent
should be included in the design unless flaring or venting is specifically required for
safety reasons. If flaring or venting is required for safety reasons an ALARP justification
was developed.
Flaring on Prelude is designed to be smokeless in accordance with the requirements
outlined in Shell Design Engineering Practice (DEP) 80.45.10.10 (2012). This
document outlined that:
o FWH Flare: Smokeless for operational case, Start-up and Shutdown;
o FDH Flare: Smokeless for operational and EDP case (not simultaneous with
operational case);
o FDL Flare: Not smokeless as relief gas content is mostly methane; and
o FWL Flare: Not smokeless (emergency events).
Under routine operating conditions and without any process upsets or passing valves,
the flares burn a small stream of fuel gas intended to maintain flares lit at all times (i.e.
fuel gas to flare pilots). This stream is estimated at ~2000 kg/h in total for all Prelude
flares. The fuel gas to maintain flare pilots and any flaring considered necessary to
address safety concerns does not constitute routine flaring as defined by the GGFR
Partnership. The key pollutant emissions from flaring include NOx, SOx, CO, PM2.5 and
PM10, as well as air pollutants such as benzene, toluene and formaldehyde (VOCs).
Removed reservoir carbon dioxide (acid gas) is disposed continuously through the
dedicated Prelude acid gas vent whilst the facility is producing. Per the base case

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design, the acid gas composition consists of more than 98% CO2, with the remainder,
being minor quantities of CH4, H2S and BTEX (benzene, toluene, ethylbenzene and
xylenes). However, feed gas sample testing performed in August 2020 showed no
traces of BTEX in Prelude’s feed gas with almost negligible quantities of H2S. As
pollutants in the feed gas are lower than the base case design, the emissions profile is
expected to have less impact than originally modelled.
Sources of volatile organic compounds (VOC) emissions include condensate loading
operations and fugitive emissions / general leaks.
Condensate loading operations, scheduled to occur once every two weeks, will initially
result in emissions of inert gases (CO2 and N2) displaced from the condensate offtake
tanker’s cargo storage tanks by the loaded condensate liquid and in the later stages of
loading, emissions of volatile organic compounds (VOCs) evolving from the
condensate itself and emitted via the tanker deck vent(s). Fugitive emissions from the
FLNG are expected to be occasional only, minor in volumes and dispersed in location.
The design standard pollutant concentrations for the steam boilers as compared to
actual emissions from stack testing results are summarised in Table 9-52 below.
Notably, the measured concentrations of NOx and PM for boilers running on fuel gas
were well below the original design standards.

Table 9-52: Measured Emission Rates for the HP Steam Boilers at FLNG

Combustion Source Average Dry Average Measured Design Standards or

Standard Stack during Sep 2019 Predicted Design Levels 18
Flow Rate per Stack Test
boiler (Nm3/min)
Steam boilers A-40010 to A- 3,508 NOx – 147mg/Nm3 NOx -240mg/Nm3
40070 (running on fuel gas) SO2 – 1.2mg/Nm3 SOx -
PM – 3.3mg/Nm3 Not applicable 19
PM -50mg/Nm3

Steam boilers A-40010 to A- 3,629 NOx – 269mg/Nm3 NOx- Not applicable.

40070 SO2 – 1.2mg/Nm3 SOx - Fuel used shall be
(running on diesel) PM – 2.3mg/Nm3 maximum 1000ppm
PM – Not applicable

There are no emissions monitoring ports available on the essential and emergency
power generation systems, therefore no air monitoring results for these systems
available. However, these other power systems are designed to meet MARPOL annex
VI specifications as a minimum. Project specifications for these systems included:
• For NOx, a marine diesel greater than 130KW constructed between 2011 and 2016:
• g/kWh = 45*n-0.2
• (n<130rpm) g/kW = 17

18Values sources from Prelude Environment Basis for Design 2000-110-G000-GE00-G00000-HX-7704-

62001

19 Meaning no project design specification was put in place for this parameter.

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• (n>2000rpm) g/kW = 9.8

• Note – N = rated engine speed (crankshaft RPM)
• For SOx, 1000ppm Sulphur content of fuel
• For PM, Not applicable.

Whilst the boilers will be operational at all times when the facility is producing, the
essential and emergency diesel generators will be used only in the event of
planned/unplanned and emergency non-routine operations and when tested as
integrity-critical equipment. The volumes of flared gas will also fluctuate above the
baseline flaring rates (i.e. pilot gas only) as a result of potential process upsets and
plant shutdowns and restarts. Acid gas venting will occur continuously whilst producing;
however, the rates and composition of the gas may change depending on the feed gas
composition.
A representative atmospheric pollutant and air pollutants inventory has been compiled
using production and mass balance data for the highest expected production year and
is presented in Table 9-53. Since emissions data has been estimated using a
combination of vendor emission guarantees where available and NPI and US EPA AP-
42 emission factors, as well as assumptions about production rates and facility uptime
for that year, the quoted numbers should be viewed as an order of magnitude estimate
only. Furthermore, emission rates provided in 2021-2025 planning range tend to have
negligible maximum Ground Level Concentration (GLC) when screening assessments
such as USEPA SCREEN are used. Table 9-55 has been developed to indicate
conservative values (based on emission inventory during design) for the purpose of the
screening assessment. The screening assessment indicates that even when the
emission rates are set to conservative values, the predicted maximum Ground Level
Concentration (GLC) are within prescribed Ambient Air Quality Limits (AAQ) at
identified receptors (FPSO@17km and Browse Island@40km). Hence, Table 9.55
values form an appropriate basis for the screening assessment using USEPA SCREEN
approach.
During normal operation, the boilers are designed to be running on fuel gas with six or
seven boilers being online. During abnormal (emergency or upset) conditions, Prelude
is designed to have a maximum of two boilers online as the boilers are not used to
continue production but rather provide sufficient electricity to power emergency
systems and basic utilities. In these situations, the boilers may run on fuel gas or diesel
depending on whether the warm end of the facility has been shut down. If boilers are
unable to run, the facility may run entirely on EDGs for small periods of time until the
boilers can be operationalised.
Air emissions predicted in the Prelude Environmental Impact Assessment included a
total NOx – 2,278 tpa and VOC – 1,799 tpa. The estimates provided below provide a
more detailed prediction of air emissions ranges which could be expected over the next
5 years of operations which will likely include the peak production year in the latter half
of the forecast range (2023/2024).
There was no feed gas throughput during 2018 NPI reporting year, and therefore no
emissions associated with boiler fuel gas combustion, acid gas venting, or fugitive
general leaks. The majority of emissions in 2020 were associated with diesel
combustion for electricity production used for lighting or motive purposes (producing
physical or mechanical motion). Electrical motive equipment includes pumps, fans

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compressors, conveyor belts etc. Electrical non-motive equipment includes arcing

furnaces, heaters, ovens etc.).

Table 9-53: Prelude FLNG Atmospheric Emissions Inventory

2020 NPI Air Emissions Actuals Emissions Rates (tonnes/a)

# Emission Source Approx. Fuel NO2 SO2 CO PM VOC

Consumption
Rate (tonnes/a)

1 Steam Boiler (Fuel 160,000 565 0.5 80 24 18

Gas)
2 Steam Boiler (Diesel) 19,000 50 0 12 0.5 0.5
3 Essential Diesel 3,500 174 0 46 5 4
Generators
4 Flaring 300,000 412 0 2,391 16 4,122
5 Acid Gas Vent 200,000 0 0 0 0 0
6 Fugitive Emissions 200 0 0 0 0 37

Total 1,201 0.5 2,529 45.5 4,181.5

2019 NPI Air Emissions Actuals Emissions Rates (tonnes/a)

Approx. Fuel
# Emission Source Consumption NO2 SO2 CO PM VOC
Rate (tonnes/ a)

Steam Boiler (Fuel

1
Gas)
200,000 594 4 182 14 8
2 Steam Boiler (Diesel) 50,000 281 1.2 78.9 2.4 1.8
Essential Diesel
3
Generators
500 10 4.8 2.1 0.3 0.2
4 Flaring 600,000 900 0 5220 33.6 9000
5 Acid Gas Vent 1,000 0 0 0 0 20
6 Fugitive Emissions 100 0 0 0 0 100
TOTAL 1785 10 5483 50.3 9130
2018 NPI Air Emissions Actuals Emissions Rates (tonnes/a)

Approx. Fuel
# Emission Source Consumption NO2 SO2 CO PM VOC
Rate (tonnes/ a)

Steam Boiler (Fuel

1
Gas)
0 0 0 0 0 0
2 Steam Boiler (Diesel) 66,313 180 1.2 45.1 11.2 1.8
Essential Diesel
3
Generators
2,621 164 0 43.8 10.2 4.1
4 Flaring 4,705 7 0 40.9 0.6 70.5
5 Acid Gas Vent 0 0 0 0 0 0
6 Fugitive Emissions 0 0 0 0 0 0
TOTAL 351 1.2 129.8 22 76.4

Emissions 2021 – 2025

Rates business planning
(tonnes/a) forecast range

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# Emission Approximate Fuel NO2 SO2 CO PM VOC

Source Consumption/Venting t/pa t/pa
Rate 2020 – 2025 t/pa t/pa t/pa
(tonnes/annum)

1 Steam 130,000 - 760,000 20 478 – 3- 68 - 395 21 - 16- 90

Boilers 2,797 18 122
(Fuel Gas)

2 Steam 5,000 - 15,000 21 14 - 41 0.1 – 3 - 10 0.7 – 0.1 – 0.4

Boilers 0.3 2
(Diesel)

3 Essential 200 – 1,000 22 13 - 63 0.004 3 - 17 0.4 - 0.3 - 2

Diesel – 2
Generators 0.02

4 Flaring 180,000 - 370,000 23 270 - - 1,566 – 21- 2,700-

555 3,219 42 5,550

5 Acid Gas 175,000 – 725,000 24 - - - - -

Vent

6 Fugitive 10,000 - 60,000 25 1955 –

emissions 11,730
(general
leaks)

Table 9-54: Range of utilisation days per year from planning assumptions of emissions forecasts in 2019

Range of Utilisation Days Per Year in Planning Assumptions in Emission Forecasts (2019)

Year On Stream Days Off Stream Days Turnaround Days

2020 104 - 229 136-261 0

2021 195 - 261 104-170 50 26

2022 294 - 315 50-71 0

2023 278 - 295 70-87 36

2024 310 - 328 37-55 0

2025 224 - 245 66-87 54

Notes: Boiler emissions were estimated based on the October 2019 Stack Testing Results. Other emission
rates were based on NPI default values and design datasheets.

The inventory indicates that emissions from the Prelude FLNG are comparable in
magnitude to emissions from other oil and gas facilities, specifically the INPEX Ichthys

20
During normal operations and highest expected production year, the consumption/venting rate will be on the high side.
21
During normal operations the consumption/venting rate will be on the low side.
22
During normal operations the consumption/venting rate will be on the low side.
23
During normal operations and highest expected production year, the consumption/venting rate will be on the low side.
24
During normal operations and highest expected production year, the consumption/venting rate will be on the high side.
25
During normal operations and highest expected production year, the consumption/venting rate will be on the high side.
26
In the business planning process for 2020, the planned shutdown for 2021 has been rescheduled to 2022.

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FPSO (Inpex Browse Ltd, 2008). Emissions from Prelude FLNG and the Ichthys FPSO
and supporting marine vessels contribute to pollutant levels in the local marine
environment airshed. The impacts of these combined emission sources on the air
quality of the airshed has been examined in a screening air quality modelling study and
is discussed in section 9.10.2 below.

9.10.2 Description and Evaluation of Impacts

Based on a conservative, screening-level assessment, maximum predicted
concentrations of combustion-related pollutants at identified receptors and attendant
ambient air quality impacts associated with the Prelude FLNG facility are concluded to
be of low magnitude. The maximum predicted concentrations of NOx, SO2 PM2.5 ,CO
and VOC at Browse Island are well below the associated ambient air quality standards
for all the scenarios examined.
Ambient air quality impacts were assessed based on a comparison with human health-
based standards. Air emissions from the Prelude FLNG facility will lead to increased
deposition of NOx, SO2 and PM2.5 on the water surface and potential impacts on
seawater and seabed sediments and other habitats for aquatic vegetation. However
due to the low levels of the contaminants, expected water column dilution and buffer
capacity of sea water, it is unlikely that deposition emissions will cause a change in
acidity/basicity (pH) to the extent that marine life is affected.
In addition to the above study, modelling of the emissions from the FLNG was done for
safety and occupational health purposes to assess potential impacts to workers aboard
the FLNG facility. These modelling studies include the following:
• Atmospheric Dispersion Study Report (2000-110-G000-GE00-G00000-HX-7180-
62101) determined if there is any occupational health and environmental impacts
from long term point source emissions: boiler exhaust during normal operations.
o CO2, H2S and SO2 health requirements are met in all cases for both working
and residential areas.
o NO2 occupational limits (in working areas, i.e. process decks and LERs) are
also not exceeded.
• Flare Flame-Out and Venting Atmospheric Dispersion Study (2000-110-G000-
GE00-G00000-HX-7180-19163) which was carried out to assess extent of hazard
associated with gas dispersion with regards to flammable and toxic risks from the
flare and vent sources.
o It is confirmed that the vents and flares height/ location is found to be safe to
avoid any flammable or toxic impact on the facility.
• PEPCI FLNG Atmospheric Dispersion Study (2000-110-G000-GE00-G00000-HX-
7180-62101) modelled the safety and health impacts of the emissions from the
boilers when running using diesel during the hook-up and commissioning phase.
o The issue of NOx is prevalent only when boilers and EDG are running on
diesel fuel. During this time, the 1 hr residential limits are exceeded for a
short percentage of time, but the occupational health limits are not
exceeded.
o Prelude uses low sulphur diesel, therefore any concern associated with SOx
has been eliminated.

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The occupational health modelling results indicate that the emissions will not result in
health and safety issues within the FLNG process area and living quarters. This
provides further evidentiary support that emissions from the facility are not likely to
impact environmental sensitive receptors further afield.
Given the above studies, no adverse environmental effects are anticipated and the
associated impacts are expected to be slight, therefore the residual risk is assessed to
be low.
Given the offshore remote context, environmental sensitivities that may be impacted by
emissions of atmospheric pollutant include only the physical environment (air quality
and visual amenity). No impacts on the socio-economic and cultural environment are
reasonably foreseeable. Impacts on the physical environment can be summarised as:
• Planned emission of atmospheric pollutants to Prelude airshed under routine
and non-routine (planned and emergency) operating conditions
• Routine and non-routine flaring resulting in smoky flare and impact on visual
amenity.
Occupational health effects associated with emissions of air pollutants are excluded
from the scope of the EP and covered in the Prelude Safety Case and supporting
occupational health management program and procedures. These have been
extensively modelled in the design phases of the Project and mitigated through design
and operating procedures.
Physical Environment
Air Quality
A screening level air dispersion modelling assessment for NOX, SO2, PM2.5 , CO and
VOC emissions was undertaken for the Prelude FLNG facility based on a conservative
approach using the US EPA SCREEN3 model. Three different operating scenarios
were examined: Normal Operations, Exceptional Case, and Worst Reasonable
Exceptional Case.
Maximum predicted ground-level concentrations were predicted at distances of 17 km
and 40 km from the Prelude FLNG representing the locations of the nearby Ichthys
FSPO facility and Browse Island respectively, and compared to the Australian Ambient
Air Quality Standards (AAQS) 27 for NO2, SO2, PM2.5 and CO. As the AAQS does not
list criteria for VOC this parameter was compared against criteria referenced in Oman
Air Quality Protection Note (AQP) 28. The modelling results indicated that ground-level
concentrations of NO2, SO2, PM2.5 ,CO and VOC at these distances were predicted to
be well below the AAQS and AQP note. As a result, ambient air quality impacts
associated with the Prelude FLNG facility were concluded to be of low magnitude.
Deposition levels could not be estimated using the screening modelling approach.
Intensity of deposition and local mixing conditions will determine whether temporary,
local pH changes are likely to occur. However due to the expected water column

27 National Environment Protection Measure for Ambient Air Quality (the 'Air NEPM'). Australian Department
of the Environment.

28 Air Quality Protection Technical Note: https://www.duqm.gov.om/upload/files/air-quality-protection.pdf

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dilution and buffer capacity of sea water it is unlikely that deposition emissions will
cause a significant change in pH affecting marine life.
Modelling Scenarios and Inputs
Three (3) different operating scenarios were considered as follows:
• Normal Operations Case:
o 6 Boilers running on natural gas.
• Exceptional Case:
o 3 Boilers running on diesel;
o 2 Essential Diesel Generators;
o Wet HP Flare: 30% of gas feed.
• Worst Reasonable Exceptional Case:
o 5 Boilers running on diesel;
o 2 Essential Diesel Generators;
o Wet HP Flare: 50% of gas feed.
As opposed to the Normal Operations case, the Exceptional and Worst Reasonable
Exceptional Cases are intermittent and associated with commissioning, start-up and
shut down conditions.
Model input data such as stack height, diameter, exit velocity, and emission rates were
compiled from design data and previous modelling assessments, or calculated based
on available information . Modelling input values used from design documents are
more conservative than the values for relevant cases outlined in Table 9-53. Modelled
emissions included combustion-related emissions from the above sources:
• Nitrogen oxides (NOx);
• Sulphur dioxide (SO2), ;
• Particulate Matter less than 2 microns aerodynamic diameter (PM2.5).
• Carbon Monoxide (CO);
• Volatile Organic Compounds (VOC’s)
A summary of modelling inputs for the FLNG emissions is provided in Table 9-55 Input
parameters for Air Modelling have been compared from the previous study (2016) with
the latest study (2020) for easy reference (additional pollutants such as CO and VOC
are included in 2020). Note that in the latest study (2020), site specific monitored
emissions data have been used where possible (e.g. Boilers Stack Monitoring Data).

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Table 9-55: Air Modelling Inputs 29 (on a per stack basis)

2016 Study 2020 Study

Stack Stack Gross Heat

Source Ht (m Diameter Exit Exit Gross Heat
Exhaust Release NOx SO2 PM2.5 Exhaust NOx SO2 PM2.5 CO VOC
ASL) (m) Velocity Velocity Release
Temp (K) Rate (106 (kg/hr) (kg/hr) (kg/hr) Temp (K) (kg/hr) (kg/hr) (kg/hr) (kg/hr) (kg/hr)
(m/s) (m/s) Rate (cal/s)
cal/s)

Boilers NG 94 2.8 11.6 453 - 33 0 6.8 21.12 365.29 NA 41.9 0.004 0.012 0.215 0.007

Boilers Diesel 94 2.8 15.2 468 - 56 293 12 21.25 427.15 NA 77.5 0.004 0.009 0.363 0.007

Diesel
94 1 35.6 638 - 22 12 3.4 21.25 427.15 NA 154.9 0.008 0.017 0.726 0.014
Generators

Wet HP Flare
147 - - - 630 77 9.1 26 - - 1.82E+08 442.4 43.5 - 2565.7 4423.6
30%

Wet HP Flare
147 - - - 1054 129 15 44 - - 3.04E+08 737.3 72.5 - 4276.2 7372.7
50%

29 Sources:

• Prelude EPCI Floating LNG Project, Gaseous Effluent List. TSC, 2011
• Prelude EPCI Floating LNG Project, Atmospheric Dispersion Study Report. TSC, 2012.
• Prelude EPCI Floating LNG Project , Flare Flame-Out and Venting Atmospheric Dispersion Study. TSC, 2013
• Physical dimensions of stack are from relevant engineering documents (in line with 2016 study).

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Model results were extracted for two (2) specific receptors distant from the Prelude
FLNG facility:
• Nearby facility (FPSO of other operator), 17 km.
• Browse Island, 40km.
Maximum predicted concentrations at the two identified receptors scenarios are
provided in Table, Table 9-57 and Table 9-58. The results show that the maximum
predicted concentrations at the identified receptors are well below the associated
ambient air quality standards for all the scenarios examined. As noted, once steady
state operations are reached, normal operations maximum scenario is expected the
vast majority of time, whilst the exceptional case maximum scenario is expected to
occur seldomly each year and the worst reasonable exceptional case scenario is
considered very rare and unlikely to occur during the life of the facility.
Table 9-56: Normal Operations Maximum Predicted Concentrations
Browse Island
FPSO (17km) (40km) AAQS
(ppm) (ug/m3) (ppm) (ug/m3) (ppm) (ug/m3)
1hr 0.002 5.0 0.002 3.60 0.12 246
NO2 Annual - 0.4 - 0.29 0.03 62
24hr - - - - - 25
PM2.5 Annual - - - - - 8
CO 8hr - 0.02 - 0.01 9 -
VOC 3hr - 0.001 - 0.001 0.24 160

Table 9-57: Exceptional Case Maximum Predicted Concentrations

Browse Island
Ave. FPSO (17km) AAQS
Pollutant (40km)
Time
(ppm) (ug/m3) (ppm) (ug/m3) (ppm) (ug/m3)
1hr 0.01 17 0.006 11.29 0.12 246
NO2
Annual 0.001 1.36 0.00 0.96 0.03 62
1hr 0.001 4.27 0.001 2.27 0.2 571
SO2 24hr 0.001 1.71 0.00 0.91 0.08 228
Annual 0.00 0.34 0.00 0.18 0.02 57
1hr 0.00 0.06 0.00 0.03 - 25
PM2.5
Annual 0.00 0.00 0.00 0.00 - 8
CO 8hr 0.013 15.76 0.009 11.19 9 -
VOC 3hr 0.011 34.49 0.008 24.55 0.24 160

Table 9-58: Worst Reasonable Exceptional Case Maximum Predicted Concentrations

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Browse Island
Ave. FPSO (17km) AAQS
Pollutant (40km)
Time
(ppm) (ug/m3) (ppm) (ug/m3) (ppm) (ug/m3)
1hr 0.01 22.11 0.008 16.15 0.12 246
NO2
Annual 0.001 1.77 0.001 1.29 0.03 62
1hr 0.002 4.34 0.001 2.31 0.2 571
SO2 24hr 0.001 1.73 0.00 0.92 0.08 228
Annual 0.00 0.35 0.00 0.18 0.02 57
24hr - 0.02 - 0.01 - 25
PM2.5
Annual 0.00 0.00 0.00 0.00 - 8
CO 8hr 0.01 18.68 0.015 12.94 9 -
VOC 3hr 0.01 40.90 0.008 28.40 0.24 160

In addition, a cumulative screening assessment for the Prelude FLNG facility in

combination with the Ichthys offshore facility with Browse Island as receptor has been
undertaken. In order to combine the concentrations from Prelude and Ichthys, it was
conservatively assumed that Ichthys is located 17 km downwind and in the direct
trajectory between Prelude and Browse Island (see Figure 9-20).

Figure 9-20: Area Map and Modelled Emission Locations

Emissions from the Ichthys project is referenced from the Ichthys EIS which provides
an aggregated total of emissions from the offshore facilities. The air emissions data
identified in the publicly available EIS is as follows:

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Figure 9-21: Excerpt from Ichthys EIS Report indicating emissions volumes

As can be seen above, Ichthys did not report any PM2.5 emissions from offshore
facilities.
Based on a review of the EIS it is expected that gas powered turbines are the major
source of air emissions from the offshore facilities. The EIS does not provide further
information on number of generators, how many are located at each facility, nor other
sources of information required for detailed air modelling such as stack dimensions,
exhaust exit velocity, etc.
Therefore, the source characterization for the emissions from the Ichthys facility has
been based on surrogate offshore FPSO facility, and assumes that all emissions are
coming from gas turbines (GTs). Due to the lack of detailed information a simplified
assumption of all emissions being discharged from one common stack was applied.
This is both a simplified and conservative approach to modelling.
Table 9-59 below provides the values used to represent the source characterisation for
the Ichthys facility. Input parameters for Air Modelling have been compared from the
previous study (2016) with the latest study (2020) for easy reference.

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Table 9-59: Ichthys Air Modelling Inputs

2016 Study 2020 Study
Gross
Stack Stack Gross
Heat
Source Ht (m Diameter Exit Exhaust Exit Exhaust Heat
Release NOx SO2 PM2.5 NOx SO2 PM2.5 CO VOC
ASL) (m) Velocity Temp Velocity Temp Release
Rate (kg/hr) (kg/hr) (kg/hr) (kg/hr) (kg/hr) (kg/hr) (kg/hr) (kg/hr)
(m/s) (K) (m/s) (K) Rate
(106
(cal/s)
cal/s)

FPSO (for
cumulative 58 2.54 30 800 - 570.6 1.8 - 30 800 - 570.6 1.8 - 661.9 125.5
assessment)

Note: FPSO data is from published EIS (in line with 2016 study)

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The screening level assessment was conducted using the SCREEN model (version
13043). SCREEN is the US EPA recommended screening model developed based on
AERMOD 30.
SCREEN is a Gaussian plume, steady state model; it assumes constant meteorology
and predicts instantaneous concentrations over the modelling domain. For this
assessment the model was run with the standard meteorological data set which
represents all possible conditions, with the output of a maximum prediction
concentration associated with the worst-case weather condition scenario. A review of
the maximum predicted concentrations for this assessment indicates that the highest
values are associated with low wind speeds of ≤ 1 m/s. Figure 9-22 provides wind
speed measurements at Prelude for the 2000-2006 time period. As can be seen, the
frequency of occurrence of low wind speeds of ≤1 m/s occur <1% of the time.
Therefore, the chance of the highest predicted concentration occurring is low.

Figure 9-22: Prelude Wind Speed Data (2000-2006)

To illustrate the impact of wind speed on predicted concentrations, the model was run
for NOx emissions from the Prelude boilers during normal operating conditions for the
full meteorological data set and various minimum wind speeds. Figure 9-23 shows the
maximum predicted concentrations with distance from the source for all wind speeds,
and wind speeds greater than 1m/s, 2m/s, 4m/s, and 6m/s. The figure indicates that the
higher wind speeds are associated with much lower predicted ground level
concentrations. As the winds at Prelude are typically higher, in the 3 to 6m/s range, this
figure demonstrates that the model predictions are conservative in comparison to the
typical wind conditions expected at the facility. It should also be noted that although the
example below is specific with respect to NOx emissions from the boilers, the same
impact of wind speed would be applicable to the other sources and contaminants,
including CO and VOC’s.

30 US EPA Technology Transfer Network, Support Center for Regulatory Atmospheric Modeling.
https://www3.epa.gov/ttn/scram/dispersion_screening.htm

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Figure 9-23: Example - Prelude Normal Operations Predicted NOx Concentrations with Varying Minimum
Wind Speeds

Screening level models provide conservative values as they provide outputs on the
centreline of the plume (where concentrations are highest) at various distances
downwind. They do not consider the frequency of these wind conditions nor the
location of a specific receptor with respect to predominant wind direction.
As the model assumes steady state, it assumes that the weather conditions are
persistent and winds are blowing in the same direction. This approach is deemed to be
conservative for receptors distant from the source. For example, the maximum
predicted concentration predicted at Browse Island is associated with a wind speed of
1 m/s. In order for the centreline of the plume to reach Browse Island from Prelude
would require 11 hours of persistent wind blowing directly towards the island.
An examination of the wind speed and direction data gathered at Prelude indicates that
the frequency of winds blowing towards Browse Islands varies between <1% and 15%
of the time, depending on season as shown in Figure 9-24 which presents the full year
wind speed and direction data for Prelude. As such, emissions from Prelude would
predominantly not be blowing towards Browse Island.

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Figure 9-24: Wind Rose for Wind Speed and Direction Data Gathered at Prelude

SCREEN only models one source at a time, therefore, the model was run multiple
times for the Prelude and Ichthys facility sources and the concentrations from each run
were conservatively summed to provide the maximum predicted concentrations. The
maximums are added together, even if they are the result of different meteorological
conditions.
In summary, the modelling approach is considered conservative due to the following:
• Highest predicted concentrations are associated with low wind speeds, which occur
infrequently at the facility. Higher wind speeds result in lower ground level
concentrations
• Wind blowing from Prelude towards Browse Island occur between <1% to 15% of
the time, while the modelling assumes that the winds are blowing towards Browse
Island 100% of the time.

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• For the cumulative scenario, Ichthys was assumed to be in the trajectory from
Prelude to Browse Island.
Model Outputs and Assessment Criteria
Predicted 1-hour concentrations were scaled to other averaging periods using the
recommended SCREEN scaling factors and compared with the Australian AAQS and
international reference for VOC has been sought as it was VOC limits were not listed in
Australian AAQS.
Applicable 1-hour, 24-hour and annual concentrations were compared with the
standards for the Normal Operations scenario.
The following should be noted with respect to the results presented:
• The direct conversion method was used to convert NOX to NO2, this approach
assumes that all NOX emissions will be converted to NO2, this is a conservative
approach as it is expected that not all NOX will convert to NO2.
• Sulphur content of the diesel will be a maximum of 500ppm.
• SO2 concentrations for the Normal operating scenario (Table 9-60) are based on
Ichthys emissions alone, as Prelude will not have SO2 emissions associated with
Normal operations.
• SCREEN conversion method was applied to convert from 1 hour to 24 hour and
annual values. The conversion factors for 24 hours is 0.4, annual is 0.08, 8 hours
is 0.7 (CO only) and 3 hours is 0.9 (VOC only).
The cumulative maximum predicted concentrations predicted at Browse Island are
provided in Table 9-60 - Table 9-62. The results show that the maximum predicted
concentrations at the identified receptor are well below the associated ambient air
quality standards for all the scenarios examined.
Table 9-60: Cumulative Prelude and Ichthys Normal Operations Maximum Predicted
Concentrations
Browse Island (40km) AAQS

Parameter (ppm) (ug/m3) (ppm) (ug/m3)

1hr 0.024 49.20 0.12 246

NO2
Annual 0.002 3.94 0.03 62

1hr - 0.14 0.2 571

SO2 24hr - 0.06 0.08 228

Annual - 0.01 0.02 57

24hr - - - 25
PM2.5
Annual - - - 8

CO 8hr 0.03 35.91 9 -

VOC 3hr 0.003 8.75 0.24 160

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Table 9-61: Cumulative Prelude Exceptional Case and Ichthys Normal Operations
Maximum Predicted Concentrations
Browse Island (40km) AAQS

Pollutant Ave.Time (ppm) (ug/m3) (ppm) (ug/m3)

1hr 0.03 69.13 0.12 246

NO2
Annual 0.003 5.53 0.03 62

1hr 0.002 4.43 0.2 571

SO2 24hr 0.001 1.77 0.08 228

Annual 0.00 0.35 0.02 57

24hr - - - 25
PM2.5
Annual - - - 8

CO 8hr 0.05 58.08 9 -

VOC 3hr 0.01 44.81 0.24 160

Table 9-62: Cumulative Prelude Worst Reasonable Exceptional Case and Ichthys Normal
Operations Maximum Predicted Concentrations
Browse Island (40km) AAQS

Pollutant Ave. Time (ppm) (ug/m3) (ppm) (ug/m3)

1hr 0.036 74.23 0.12 246

NO2
Annual 0.003 5.94 0.03 62

1hr 0.002 4.50 0.2 571

SO2 24hr 0.001 1.79 0.08 228

Annual 0.00 0.36 0.02 57

24hr - - - 25
PM2.5
Annual - - - 8

CO 8hr 0.049 60.99 9 -

VOC 3hr 0.015 51.22 0.24 160

Under normal operating conditions, there will be no SO2 emissions from the Prelude
FLNG. Figure 9-25 shows the predicted SO2 concentrations are below the AAQS
across the domain, including in areas where there are no receptors.

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Figure 9-25: Exceptional Case Predicted SO2 Concentrations based on Diesel Sulphur Content of 500ppm

Visual Amenity (Smoky Flare)

Smoke is visible when there is unburnt cracked carbon (soot) coming out of the flare.
To reduce the amount of soot coming out of the flare, a flare steam injection system
has been installed on Prelude FLNG. Steam is provided to the high pressure dry and
wet flares and the low pressure wet flare to cool the flare tips and prevent thermal
cracking.. The steam flow provides the ideal environment for the flare to suck in more
oxygen (O2) to can react with the remaining cracked carbon. This will reduce the
amount of visible smoke coming out of the flare. The low pressure dry flare is
predominantly methane, which doesn’t crack and cause smoke, hence steam is not
required for this flare.
Operational experience and vendor data indicate that at the highest flare combustion
efficiency (lowest formation of VOC and particulate), the flare is still not completely
smokeless. There is a trade-off to consider, more steam will make the flare smokeless
and less efficient but will reduce the visible impact. However, the increase in steam
production for the flare will also consume more fuel gas, increasing emissions as a
result.
Apart from the aesthetic impact associated with a slightly smoky flare, there would be
no material environmental impacts to local and regional airshed quality. In terms of
health impacts, a Flare Flame-Out and Venting Atmospheric Dispersion Study (Shell
Australia, 2013) was carried out to assess the extent of hazards associated with gas

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dispersion with regards to flammable and toxic risks from the flare sources. The study
confirmed that the height and position for each flare was a suitably safe distance to
work places and the living quarters to avoid any flammable, acute toxic or chronic
exposure impacts at the facility. It is feasible for a flare flame out to occur, however
design measures and controls are in place to prevent this occurring. The flare system
has an automatic re-ignition control that sparks every 7 seconds, if the flame isn’t on
after 60 seconds, operator intervention is required to ignite the flame. The flare also
has remote manual ignition controls that can be used. The consequence of this event is
considered slight due to the infrequency of such an event occurring and the controls in
place to manage a flame out. Although this event is heard of in industry, the risk and
likelihood for Prelude is low.

9.10.3 Impact Assessment Summary

Table 9-63: Atmospheric Pollutant and Air Toxics Emissions Evaluation of Residual
Impacts

Consequence
Sensitivity
Magnitude

Residual
Environmental Receptor

Impact
Evaluation – Planned Impacts
Physical Environment (Impacts on Air
-1 M Slight
Quality)
Physical Environment (Impacts on Visual
-1 M Slight
Amenity)
Biological Environment N/A N/A N/A
Socio-Economic Environment N/A N/A N/A

Table 9-64: Atmospheric Pollutant and Air Toxic Emissions Evaluation of Residual Risks
Residual Risk
Consequence

Likelihood

Environmental Receptor

Evaluation – Unplanned Risks

Physical Environment Slight C Dark Blue
Biological Environment N/A N/A N/A
Socio-Economic Environment N/A N/A N/A

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9.10.4 ALARP Assessment and Environmental Performance Standards

Table 9-65: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
Elimination Use of renewable energy (e.g. No Use of solar, wind or wave energy for a continuously N/A N/A N/A
solar, wind and wave) in lieu of running operation does not have the required
fossil fuels for power generation reliability and will also require additional space and
and marine vessel propulsion capital investment which are not justified. Use of
renewable technology for a complete offshore LNG
processing facility is not yet technologically proven
and therefore not available.
Elimination Flare Flame Outs Prevented Yes The flare system is a safety and loss prevention 8.1 No flare flame-outs Incident reports of
system and is required for the safe disposal of occur on the Prelude a flare flame out
hydrocarbons in the event of process upsets or flare system whilst it is which was not auto
emergency situations. Flaring of hydrocarbon intended to be in ignited on Prelude
reduces the GHG emissions in comparison to these operation. whilst the flare is in
gases being vented. operation.
Flaring during the Prelude start-up process has been
higher than originally anticipated due to unforeseen
lower than expected facility reliability, availability and
utilisation performance. However, Shell is striving to
continually optimize and improve Prelude’s flaring
performance through addressing key causes of the
facility’s reliability, availability and utilisation
performance in the immediate future. Mitigating
flaring to ALARP will also result in the biggest
improvements to Prelude’s GHG emissions profile
and emissions intensity.. Shell is inherently
incentivised to maximise all three of these areas to
improve economic returns from the facility so there
is no EPS appropriate to include to address this
issue.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
There have been no flare flame outs on Prelude to
date. Design measures are in place to prevent this
occurring. If a flare flame out where to occur, this
could result in a short term spike increase in air
pollutants from Prelude, however auto ignition
controls are in place to mitigate this risk A flare
flame out would be recorded if the auto ignition for
the flare did not occur.
Elimination Recover the VOC emissions No VOC emissions during condensate loading cannot N/A N/A N/A
displaced during condensate be eliminated as this would require an additional
loading and reuse in the process. complex installation to separate hydrocarbons from
inert gas, possibly liquefy them and compress them
to reuse in the process. This would lead to additional
space requirements at the facility, congestion and
sources of fugitive emissions for an infrequent
operation (condensate loading occurs once in a
fortnight). This option is considered to be
disproportionate and is ALARP.
Substitution Use of electric motor drivers or No Early design considered use of variable electric N/A N/A N/A
aero-derivative GTs motor drivers of 80MW each, with the power
demand of 200MW provided by a bank of aero
derivative gas turbo-alternators, which are more
efficient than a steam boiler solution. Steam for
process use was to be generated by Waste Heat
Recovery Units (WHRU) in the GT exhaust stacks.
This arrangement was not found to be sufficiently
electrically stable, particularly in upset and start-up
conditions. Lack of stability would result in lost
production and extended flaring leading to more
atmospheric pollutant and GHG emissions, thereby
negating the energy efficiency benefits achieved
through the application of GT.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
Direct drive aero derivative GTs were also
considered to improve fuel efficiency by about 25%
over the use of steam boilers, however the design
was not mature enough to be adopted for the
Prelude FLNG.

Steam turbines were the option selected. Seven

steam boilers generate sufficient steam to drive the
main compressors and supply 120MW. This is less
energy efficient than the other two options, resulting
in an 8% fuel use increase, but is a more robust and
reliable design in terms of equipment reliability. The
boilers efficiency is anticipated to be greater than
90%.
Engineering The boilers are designed to IFC Yes Adoption of good industry practice available at the N/A N/A - The design N/A
Guidelines for Thermal Power; time Prelude FLNG was designed and constructed. features were
the essential generators to IFC selected, installed and
General EHS Guidelines; and the commissioned prior to
emergency generators to the commencement of
MARPOL 73/78 Annex VI. this EP, and are
therefore not described
in further detail here as
an EPS.
Engineering HP Steam boilers designed as Yes Fuel gas, produced at Prelude, is a cleaner burning 8.2 Limit boilers running Daily report
dual fuel and will be operated on fuel in comparison to diesel and will be preferentially on diesel to periods
fuel gas during steady state used during normal operations. The use of low when fuel gas is not
production operations sulphur diesel will be required only during occasional able to reasonably be
shutdown and start-up scenarios. used including periods
such as start-up and
shut down.
Engineering Use of end of stack technology No End of stack technology is not an efficient way to N/A N/A N/A
(e.g. scrubbers or filters) to clean minimise emissions due to additional material and

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
the exhaust gas of nitrogen labour requirements to maintain scrubbers or filters
oxides or particulate matter. in working condition. Additional safety and
operability hazards and generation of solid waste
could outweigh the benefits of this technology.

Furthermore, modelling of a number of scenarios

indicated that air quality from releases of exhaust
gas will not exceed the AAQS criteria at the nearest
receptors.
Engineering Inject steam into the flare system No A flare steam injection system is designed and N/A N/A N/A
in order to reduce smoky installed on Prelude FLNG. Steam is provided to the
appearance. high pressure dry and wet flares and the low
pressure wet flare to primarily cool the flare tips and
prevent thermal cracking.

Operational experience and vendor data indicate

that at the highest flare combustion efficiency
(lowest formation of VOC and particulate), the flare
is still not completely smokeless. Additional steam
injection can result in a smokeless but less efficient
flare, thus emitting more uncombusted fuel gas as
well as additional GHG emissions from the process
of producing more steam. The steam injection to the
flare will prioritise flare integrity and GHG
optimization over air pollutant reduction. An overall
improved environmental outcome is achieved
following this approach due to the limited effect of air
emissions on local and regional receptors and
benefit from reducing GHG emissions using this
approach.
Engineering Flaring or incineration of the acid No As the acid gas stream consists of more than 98% N/A N/A N/A
gas stream to oxidise H2S and CO2, to oxidise and render the hazardous

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
the residual hydrocarbons in the components of the stream (i.e. H2S, BTEX, PAH and
gas including methane and CH4) non-hazardous, it will be required to enrich the
BTEX. acid gas with large volumes of hydrocarbons in
order to raise the calorific value of the gas and burn
it. This will lead to emissions of other pollutants
(NOx, SOx, PM, CO) and more GHG emissions to
atmosphere and the installation of a more complex
system to operate on the facility in comparison to a
vent stack. The atmospheric dispersion study
showed that the level of pollutants near living
quarters or work sites will be sufficiently low if the
acid gas vent is 20m below the flare.
Engineering Fugitive emission design controls Yes Fugitive emissions in this context are those 8.3 Undertake topside Records of leak
unintentional emissions that occur from equipment hydrocarbon process detection and
or component leaks, i.e.: from valves or flanges in modules fugitive repair survey and
any hydrocarbon processing areas of the plant. emissions / general associated
Fugitive emissions make up <1% of the air leaks survey on at maintenance
emissions from the facility. least an annual basis repair records
As outlined in the Prelude Environment Basis of and repair identified in where relevant.
Design, fugitive emissions on Prelude FLNG shall be accordance with the
significantly reduced by: maintenance work
order system.
• Use of valves with bellow or double packing
seals or equally efficient equipment;
• Magnetically driven or canned pumps, or
pumps with double seals and a liquid
barrier;
• Minimisation of the number of flanges;
• Closed sampling systems;
• Drainage of containment effluents in closed
system;

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
• Use of relief valves instead of open vents in
tank roofs; and
• Use of pumps with double mechanical
seals must be used for all substances,
except inert liquid.
This is demonstrated effective during the operation
of Prelude by the results of the most recent leak
detection and repair (LDAR) surveys. The last
survey completed in second half of 2019 found 7
leaks up to a maximum leak rate of 34% Lower
Explosive Limit @ 100mm. All topside hydrocarbon
containing modules on Prelude are surveyed for
fugitive emissions at least once per year whilst the
facility is producing.
Engineering Maintenance of the flare system Yes During normal operations there are no practically 8.4 Flare system and flow Maintenance
feasible ways to conduct maintenance on the meters will be records
operating flare system as the pilot flare is ignited all maintained in
the time. The flare system will be maintained accordance with the
according to the maintenance management system maintenance
which allows for maintenance during certain management system.
shutdown events when the flare system is not
operational. The maintenance vent is used as flare
relief when the flare undergoes maintenance.
Flare flow meters, upstream of the actual flare, are
maintained according to the maintenance standards
to ensure they are within reliability, availability and
accuracy standards for this equipment. This ensures
the optimization of flare performance in minimizing
GHG emissions and associated VOC’s occurring at
the flare.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
Administrative Implement an adaptive stack Yes A stack emissions monitoring program will be 8.5 Representative boiler Stack testing
and Procedural emissions monitoring program implemented to validate pollutant emission rates for stack samples carried reports and
Controls (Section 9.10.5) the boilers. The results of the program will be used out at least once and assessment
to decide on the need of additional monitoring scope an assessment made
and frequency (adaptive management approach) on adaptive
and whether additional modelling studies are management controls.
required.
Administrative Implement a boiler surveillance Yes Operating the boiler system within the design 8.6 A surveillance program Trends/data
and Procedural program to ensure boilers are operating envelope and at the targeted/design is in place for the showing operation
Controls operating within the design efficiency provides a degree of assurance that the boilers and power within operating
operating envelope. emission levels are within the levels guaranteed by generation units to envelope.
the vendor of the equipment. Parameters monitored ensure that they are
includes: operating within the
design operating
• Type of fuel used envelope.
• Quantity of fuel used
• Air flow (or fan speed)
• Process temperature
• Process oxygen content

Administrative Use low sulphur fuel oil/ diesel (< Yes This MARPOL Annex VI requirement, enforced by 8.7 Use only low sulphur Sulphur content of
and Procedural 0.5% m/m S) for boilers and AMSA Marine Order 97, came into force from 1 fuel oil/ diesel (<0.5% diesel, % w/w as
Controls marine support vessels January 2020 and applies to all marine vessels m/m S) for FLNG and verified in bunker
supporting operations operating in the field including offtake tankers. This marine support receipts delivered
requirement will also be adopted for FLNG. vessels. to the FLNG on
loading and bunker
receipts for marine
support vessels
Administrative Prelude FLNG and specified Yes AMSA Marine Order 97 requires Prelude FLNG and 8.8 Prelude FLNG and Assurance records
and Procedural marine vessels supporting specified marine vessels to possess the applicable specified vessels are confirming SEEMP
Controls Prelude operations comply with pollution prevention and energy efficiency required to have the and IAPP, EIAPP,
AMSA Marine Order 97 (Marine certificates. These certificates include Engine following valid IEE certificates are
Pollution Prevention – Air International Air Pollution Prevention Certificate documentation as in place for

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
Pollution) and the requirements (EIAPP), International Air Pollution Prevention required by vessel Prelude FLNG and
of the Shell Marine Assurance Certificate (IAPP) and an International Energy class, size and type 31: specified vessels.
Process and procedures Efficiency (IEE) Certificate. In addition, all vessels • EIAPP certificate;
regarding management of air with a gross tonnage of 400 or more are required to
pollution as required by vessel carry a Ship Energy Efficiency Management Plan • IAPP certificate;
class, size and type. (SEEMP). These requirements are also recognised • IEE certificate; and
and enforced in the Shell Marine Assurance Process • SEEMP.
and procedures.
Administrative The maintenance and marine Yes An removable elbow is used to manually line up the 8.9 No venting of Incident reports of
and Procedural vents will be vented to the flare header to vent to flare whenever there are hydrocarbons will cold venting
Controls system where anything but trace hydrocarbons in the mixture. This is captured in occur on Prelude. events if it occurs
(<2%) hydrocarbons requires OPS_PRE_009565 - Prepare LNG Storage Tank for as an unplanned
disposal. Maintenance. It has steps to make sure that the event.
system is lined up to flare whilst warming up the tank Nothing except trace
hydrocarbons (<2%) PI records confirm
and whilst purging with nitrogen. It is not until the gas composition
aerating stage that the gas is directed to atmosphere will be vented to
atmosphere from the vented to
through the maintenance vent – to avoid oxygen atmosphere is <
ingress into the flare system. At this point there marine or maintenance
vents. 2% hydrocarbons.
should be minimal hydrocarbons in the vessel (the
procedure advises to stop nitrogen purge when the
hydrocarbon content is less than 2%).
The same applies for the purging of inert gases from
LNG carriers, where OPS_PRE_002789 - inert
tanker gas up and col down – ensures that the
system is lined up to flare by swinging the same
moveable elbow.

31 Advice from the Recognised Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement

Controls Performance Criteria
Standard (EPS)
Administrative Prelude FLNG LOPC Yes Planned venting of process hydrocarbons (methane, 8.10 No significant loss of Incident reports of
and Procedural Management Procedure ethane, propane, butane, LPG or LNG) to primary containment LOPC events.
Controls (OPS_PRE_012373) atmosphere does not occur on Prelude. It is an from process
important part of operating the facility to keep hydrocarbons to
hydrocarbons contained within the process systems. atmosphere as defined
This control does not include fugitive emissions in the Prelude FLNG
associated with general leaks, which includes weeps LOPC Management
and seeps from valves, flanges and other process Procedure
areas which are not considered a LOPC. Definitions (OPS_PRE_012373).
of LOPC’s greater than weeps and seeps or minor
LOPC’s is outlined below:
Significant LOPC. Detectable by a gas detector:
• ≥100% LEL at ~ 1m
• ≥20% LEL at ~ 5m

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9.10.5 Adaptive Stack Monitoring Program

The intent of the adaptive stack monitoring program for the Prelude steam boilers is to
verify that ‘end of pipe’ pollutant emission rates comply with the design emission rates
for the boilers, specified in Table 9-52. These design emission rates have been used in
the screening air quality modelling, discussed in Section 9.10.2, which provides the
evidentiary support for determining the acceptability of Prelude operations impact on
ambient air quality.
The two decision points that inform the planned stack monitoring program are the
compliance to the design emission rates for the boilers and the compliance to the
impact acceptance criterion specified in Section 9.10.6 below. Responses to these
questions will inform the adaptive actions as per Figure 9-26 below.

Figure 9-26: Flowchart: Adaptive Response Stack Testing Program

9.10.6 Acceptability of Impacts

Table 9-66: Acceptability of Impacts – Atmospheric Emissions

Receptor Receptor Acceptable Level of Are the Impacts Acceptability

Category Sub- Impact of an Acceptable Assessment
category Level?
Physical Air Quality No significant impacts Yes Screening air quality
Environment to air quality defined as assessment indicates
no substantial change that predicted ground
in air quality which may level concentrations of
adversely impact on pollutants at the closest
biodiversity, ecological sensitive receptors for
the worst-case modelling
conditions are below

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integrity, social amenity 75% of the current

or human health. NEPM ambient air
quality standards.
The worst-case wind
conditions associated
with highest predicted
ground level ambient
pollutant concentrations
at the closest sensitive
receptors (which are well
below 75% of the current
ambient air quality
standards) persist only
1% of the time.
Biological N/A N/A N/A N/A
Environment
Socio- N/A N/A N/A N/A
economic
and Cultural
Environment

The assessment of atmospheric pollutant emissions determined the impact magnitude

to be minor. Given that air quality in the area is generally expected to be very high and
the lack of sensitive human receptor populations in the Prelude airshed as defined in
the Air Quality NEPM (NEPC, 1998), the residual impact consequence ranking is
assessed as Slight (Magnitude -1, Sensitivity – M) and therefore acceptable (Table
9-63). Impacts on air quality have also been considered in the following context.
Principles of ESD
The impacts from atmospheric pollutant and air toxics emissions are acceptable and
consistent with the principles of ESD based on the following points:
• The environmental values/sensitivities within the Operational Area and the
regional airshed are not expected to be significantly impacted.
• The precautionary principle has been applied to the impact modelling study and
in the impact assessment.
Relevant Requirements
Management of impacts from atmospheric emissions is consistent with relevant
legislative requirements, including:
• Air quality in the Prelude regional airshed complies with the current NEPM
Ambient Air Quality Standards (National Environment Protection Council, 1998)
as well as with the proposed draft NEPM Ambient Air Quality Standard (National
Environment Protection Council, 2019).
• Marine fuel oil used by HP Steam Boilers and marine vessels supporting
operations complies with 1 January 2020 MARPOL Annex VI requirement for
0.5% m/m S content in marine fuel oil and diesel.

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Matters of National Environmental Significance

Threatened and Migratory Species
The evaluation of atmospheric pollutant emissions from the Prelude FLNG facility and
supporting marine operations indicates significant impacts and risks to threatened and
migratory species will not credibly result from combustion of fuels, flaring, acid gas and
VOC venting and fugitive emissions aspects of the Prelude petroleum activities.
Alignment of the Prelude petroleum activities with management plans, recovery plans
and conservation advice for threatened and migratory fauna is provided in Table 9-67.
Commonwealth Marine Environment
The impacts and risks from atmospheric pollutant emissions from the Prelude field on
the Commonwealth marine environment will not exceed any of the significant impact
criteria provided in Table 9-67.

Table 9-67: Summary of Alignment of the Impacts from the Atmospheric Pollutant
Emissions Aspect of the Prelude petroleum activities with Relevant Requirements for
EPBC Threatened Fauna

Matters of MNES Acceptability Considerations Demonstration of Alignment as Relevant

National (Significant Impact Criteria, EPBC to the Project
Environmental Management Plans/Recovery
Significance Plans/Conservation Advices)
Threatened and None applicable to atmospheric N/A
Migratory Species pollutant emissions
Wetlands of None applicable to atmospheric N/A
International pollutant emissions
Importance
Commonwealth No significant impacts on Air Quality Criteria for significant impacts and risks to
marine area air quality over the Commonwealth Marine
area where the Prelude project will operate
have not been triggered by atmospheric
pollutant emissions from the Prelude field.

Internal and External Context

There have been no objections or claims raised by Relevant Persons in preparation of
this EP related to atmospheric pollutant and air toxics emissions aspect.
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with Shell’s internal requirements.
Shell has adopted the World Bank Global Gas Flaring Reduction (GGFR) initiative
(Zero Routine Flaring by 2030). This initiative is intended to avoid flaring of associated
gas from oil developments and does not apply to LNG projects however Shell
establishes flaring management plans for all major installations to ensure flaring is
minimised to ALARP . Non-routine flaring, which nevertheless should be minimised,
and flaring for safety reasons is explicitly excluded from this initiative.
Acceptability Summary
The assessment of impacts from atmospheric pollutant and air toxics emissions
determined the residual impact rankings to be Slight (Table 9-4). As outlined above, the

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acceptability of the impacts and risks from this aspect have been considered in the
context of:
• The established acceptability criteria for impacts and risks for this aspect
• ESD
• Relevant legislative requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
The residual impacts are slight which Shell considers to be inherently acceptable if they
meet legislative and Shell requirements. The discussion above demonstrates that
these requirements have been met in relation to the atmospheric pollutant emissions
aspect.
Based on the points discussed above, Shell considers the impacts from atmospheric
pollutant emissions associated with Prelude operations to be acceptable and ALARP.

9.10.7 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

Predicted ground level concentrations of Steam boilers adaptive stack emissions
atmospheric pollutants are below 75% of the monitoring (validation of vendor design emission
applicable ambient air quality criteria 32 rates).
Atmospheric pollutant and air toxics emissions
inventory (as part of NPI report).

9.11 Greenhouse Gas Emissions

9.11.1 Aspect Context

Operating the Prelude FLNG facility and producing LNG, LPG and condensate results
in GHG emissions from various sources such as:
• Combustion of fuel (diesel and fuel gas) for power generation

32 The 75% of AAQS acceptance criterion for level of impact for ambient air quality has been derived from

the National Environment Protection Council (Ambient Air Quality) Measure, Technical Paper No. 4,
Screening Procedures (National Environment Protection Council, 2007). This paper provides screening
criteria against which jurisdictions can assess the monitoring needs of their regions where reduced or no
direct monitoring is justified in accordance with Clause 14 (3) of the Ambient Air Quality NEPM: “Fewer
performance monitoring stations may be needed where it can be demonstrated that pollutant levels are
reasonably expected to be consistently lower than the standards mentioned in this Measure.” The NEPM
Peer Review Committee (PRC) recommended using 75% of the AAQS criteria as the maximum acceptance
limit for any ambient air pollutant screening method (e.g. inventory, modelling or monitoring), below which
no air quality monitoring, or no additional air quality monitoring stations need to be established. It is further
recommending lower and specific to each pollutant threshold levels when taking into account the difference
in screening methods, their reliability and the exposed populations. The threshold level of 75% of the AAQS
is considered appropriate for an acceptable level of impact when assessing air emissions from the Prelude
field as no sensitive receptors as defined in the Ambient Air Quality NEPM are present in the Prelude airshed.

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• Flaring of hydrocarbon for process safety purposes

• Venting of reservoir CO2.
• Fugitive emissions / General Leaks
• Combustion of fuel from transportation purposes – e.g. vessels supporting Prelude
operations
The above sources are further discussed in detail in Section 9.10.1.
GHG Emissions Inventory
GHG emissions forecasting for Shell forms part of the annual Operating Plan (OP)
process described in section 10.1.11.
Accounting of all GHG emissions has been recorded and reported under the NGER Act
since the arrival of Prelude at location in 2017.
Predicted total gross annual GHG emissions from the Prelude FLNG, over its operating
life, are not expected to exceed 2.7Mt CO2-e, on average. Over the next five years of
operation (2021 – 2025 inclusive), annual GHG emissions are not expected to exceed
2.6Mt CO2-e, on average. The maximum gross scope 1 emissions limit from the Prelude
FLNG is not expected to exceed 2.95Mt CO2-e in any given year, on an aggregate
basis.
This is based on Operating Plan forecasts and is considered a confident basis for
maximum facility GHG emissions as some uncertainty is accounted for in the figures
provided. The breakdown of Prelude’s GHG inventory during stable operations is
shown in . The chart is based on OP20 forecasts for the year of peak production.
Prelude emissions inventory would be expected to vary for periods when the facility is
not operating stably during process and plant operational upsets which are
experienced for gas processing and/or LNG production. However, this is not expected
to result in an increase in total emissions outlined above.

Flaring Fugitives
6% 2%

AGRU
36%

Combustion
56%

Figure 9-27: Prelude’s GHG emissions inventory during stable operations.

Table 9-68: Prelude FLNG Actual Annual GHG emissions in early start-up phases

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Type Actual Emissions (CO2-e kt/year) 33

FY2017/2018 FY 2018/2019 FY 2019/2020

Reservoir
CO2 0 69 193
Fuel
combustion 240 567 1,124
Flaring 13 1,680 789
Fugitive 0 1 3
Actual total
GHG
emissions 253 2,317 2,109
OP year
emissions
forecast 398 2,570 2,787

To put Prelude’s gross scope 1 GHG emissions into context, in the financial year 18/19
Prelude contributed approximately 2.3Mtpa of the 537.5Mtpa total domestic emissions
in Australia (Commonwealth of Australia 2019). There are many publications of the
global GHG emissions and projected pathways of impacts under different modelled
climate change scenarios. The latest figures from the Global Carbon Project, which
releases annual data on GHG emissions, backed up by peer-reviewed publications,
identify global fossil fuel GHG emissions in 2020 to be approximately 34,100Mtpa
(Global Carbon Project 2020). The IEA World Energy Outlook (2019) predicts world
energy related GHG emissions to be 35,589Mtpa in the Stated Policies Scenario
(STEPS) and 15,796Mtpa in the Sustainable Development Scenario (SDS) by 2040.
Table 9-69 compares the Prelude GHG emissions against these amounts.
Table 9-69- Comparisons between Prelude FLNG, Australian and Global GHG emissions
Facility GHG Australian Percent of STEPS SDS Global
Emissions 34 Emissions Global Global Emissions %
(Mtpa CO2-e) Emissions in Emissions in in 2040
2020 2040
Prelude FLNG 2.7 0.5% 0.0067% 0.0076% 0.017%

9.11.2 Description and Evaluation of Impacts

This section describes how climate change, in general, may affect the Australian
environment. As will be explained in the evaluation, while there is a relationship
between GHG emissions and climate change, it is not possible to know the exact
contribution of Prelude’s emissions to these possible effects.
CSIRO (2018) is forecasting that Australia is projected to experience the following
climate changes:
• increases in sea and air temperatures, with more hot days and marine
heatwaves, and fewer cool extremes;

33 Based on reported financial year NGER information.

34 Based on expected average emissions over the life of the Prelude FLNG facility.

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• sea level rise and ocean acidification; and

• decreases in rainfall across southern Australia with more time in drought, but an
increase in intense heavy rainfall throughout Australia.
A summary of the predicted effects to key Australian ecosystems as a result of climate
change is presented in Table 9-70. Most marine and terrestrial ecosystems are
susceptible to climate change; however, the predicted impact is highly variable, both
between ecosystems and within individual ecosystems.
Changes in climate, such as altering temperature, rainfall patterns and fire regimes,
due to climate change are likely to result in changes in vegetation structure across all
terrestrial ecosystems within Australia (Dunlop et al. 2012). Increases in fire regimes
will impact Australian ecosystems by altering composition structure, habitat
heterogeneity and ecosystem processes, and may assist in the spread of introduced
species (which may further alter or increase the incidence of fires). Changes in climate
variability, as well as averages, could also be important drivers of altered species
interactions (Dunlop et al. 2012).
Table 9-70: Projected Effects of Climate Change on Key Australian Ecosystems
Selected Component of Projected Effects
Environmental Change
Coral Reefs
CO2 increases leading to Reduction in ability of calcifying organisms, such as corals, to build and maintain
increased ocean acidity skeletons.
Sea surface temperature If the frequency of bleaching events exceeds the recovery time, reefs will be
increases, leading to coral maintained in an early successional state or be replaced by communities
bleaching dominated by macroalgae.
Warming will increase the susceptibility of corals to diseases.
Potential for new reefs to develop at higher latitudes where suitable substrates are
available and until light becomes limiting; potential decrease in beta diversity of
coral communities as tropical-adapted taxa expand their range to the south,
amplified by differential survival of different taxa,
Increases in cyclone and Increased physical damage to reef structure.
storm surge
Oceanic Systems (including planktonic systems, fisheries, sea mounts and offshore islands)
Ocean warming Many marine organisms are highly sensitive to small changes in average
temperature (1–2oC), leading to effects on growth rates, survival, dispersal,
reproduction and susceptibility to disease. Increasing temperatures reduce larval
development time, potentially reducing dispersal distances; warm-water
assemblages may replace cool-water communities.
Changed circulation Distribution and productivity of marine ecosystems is heavily influenced by the
patterns, including increase timing and location of ocean currents; currents transfer the reproductive phase of
in temperature stratification many organisms, therefore playing an important role in dispersal and maintenance
and decrease in mixing of populations. Climate change may suppress upwelling in some areas and
depth, and strengthening of increase it in others, leading to shifts in location and extent of productivity zones.
East Australian Current
Changes in ocean chemistry Increasing CO2 in the atmosphere is leading to increased ocean acidity and a
parallel decrease in the availability of carbonate ions, which are the building blocks
of calcium carbonate skeletons (such as those of many planktonic species and
corals. Increased dissolved CO2 may increase productivity.
Estuaries and Coastal Fringe (including benthic, mangrove, saltmarsh, rocky shore, and seagrass
communities)
Sea level rise Landward movement of some species (particularly mangroves) as inundation
provides suitable habitat, changes to upstream freshwater habitats will have flow-
on effects to species such as wetland birds.

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Selected Component of Projected Effects

Environmental Change
Increase in water Effects on phytoplankton production will affect secondary production in benthic
temperature communities.
Savannas and Grasslands
Elevated CO2 Shifts in competitive relationships between woody and grass species due to
differential responses.
Increased rainfall in north Increased plant growth will lead to higher fuel loads, in turn leading to fires that are
and north-west regions more intense, frequent, occur over large areas and occur later in the dry season.
Change to ecotonal boundaries between savanna woodlands, grasslands and
monsoonal rainforest patches. Changes in rainfall seasonality are likely to be more
important than changes in amount.
Tropical Rainforests
Warming and changes in Increased probability of fires penetrating rainforest vegetation resulting in shift
rainfall patterns from fire-sensitive vegetation to communities dominated by fire-tolerant species.
Cool-adapted species forced to higher elevations, altering competitive interactions.
Change in length of dry Altered patterns of flowering, fruiting and leaf flush will affect resources for
season animals.
Increased intensity of Increased physical disturbance to forests, which alters gap dynamics and
storms/tropical cyclones succession rates; shallow-rooted tall rainforest trees are particularly susceptible to
uprooting, breakage and defoliation.
Rising atmospheric CO2 Differential response of different growth forms to enhanced CO2 may alter
structure of vegetation.
Temperate Forests
Potential increases in Changes in structure and species composition of communities with obligate
frequency and intensity of seeders may be disadvantaged compared with vegetative resprouters.
fires
Warming and changes in Potential increases in productivity in areas where rainfall is not limiting;
rainfall patterns reduced forest cover associated with soil drying projected for some Australian
forests.
Rising atmospheric CO2 Overall increase in productivity and vegetation thickening.
Inland Waterways and Wetlands
Reductions in Reduced river flows and changes in seasonality of flows; reduction of the area
precipitation, increased available for waterbird breeding. More intense rainfall events will increase flooding,
frequency and intensity of affecting movements of nutrients, pollutants and sediments, riparian vegetation,
drought and erosion. Groundwater dependent ecosystems may be negatively affected.
Changes in water quality, May affect eutrophication levels, incidence of blue-green algal outbreaks; loss of
including changes in nutrient cool-adapted species and increase in populations of warm-adapted species.
flows, sediment, oxygen and
CO2 concentration
Sea level rise Saltwater intrusion into low-lying floodplains, freshwater swamps and groundwater;
replacement of existing riparian vegetation by mangroves.
Warming of water column; Changes in abundance of temperature-sensitive species, such as algae and
increase in depth of zooplankton; reduction in depth of lowest oxygenated zones in some instances.
seasonal thermoclines in still
water
Arid and Semi-arid Regions
Increasing CO2 coupled with Interaction between CO2 and water supply critical, as 90% of the variance in
drying in some regions primary production can be accounted for by annual precipitation.
Shifts in seasonality or Any enhanced runoff redistribution will intensify vegetation patterning and erosion
intensity of rainfall events cell mosaic structure in degraded areas. Changes in rainfall variability and amount
will also affect fire frequency. Dryland salinity could be affected by changes in the
timing and intensity of rainfall.

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Selected Component of Projected Effects

Environmental Change
Warming and drying, leading Reduction in patches of fire-sensitive mulga in spinifex grasslands potentially
to increased frequency and leading to landscape-wide dominance of spinifex.
intensity of fires
Alpine/Montane Areas
Reduction in snow cover Potential loss of species dependent on adequate snow cover for hibernation and
depth and duration protection from predators; increased establishment of plant species at higher
elevations as snowpack is reduced.

(adapted from Steffen et al. 2009)

Emissions are primarily classed as Scope 1 (direct emission from own facilities or
businesses) or Scope 2 (indirect emissions when purchasing steam or electricity for
use) GHG emissions. Prelude does not have any Scope 2 emissions. The broader
impacts from GHG emissions are typically considered by the international community
at an ecosphere level, most frequently in terms of an increase in global temperatures.
Table 9-70 identified the climate projections on the Australian environment from the
increase in global temperatures.
Climate projections depend upon emission/concentration/radiative forcing scenarios,
which are based on assumptions concerning, for example, future socio-economic and
technological developments that may or may not be realised and are therefore subject
to substantial uncertainty (UNITAR 2015).
Climate projections are distinct from climate predictions. Climate predictions are
estimates of future natural conditions, while climate projections are estimates of future
climates under the assumptions of future human related activities such as socio-
economic and technical developments. Making a prediction of GHG emission impacts
at the ecosphere level is an inherently complex exercise because of the influence of
variables such as surface pressure, wind, temperature, humidity and rainfall within
multiple ecosystems. The listed items are all interdependent variables that contribute
to a global temperature increase. For each variable, a series of generalising
assumptions would be required to be able to make a sensible calculation of the
impacts. Considering the complex and dynamic natural processes within the
ecosphere, there is substantial uncertainty in determining a specific increase in global
temperatures due to Prelude and its emissions.
It is equally speculative to suggest an isolated climate event, or series of climate
events, that lead to a change to any environmental value or sensitivity within Australia
(including Matters of National Environmental Significance (MNES)), are solely
attributable to a specific increase in global temperature. As such, it is not possible to
isolate the influence of Prelude emissions to any conclusive impact on the Australian
environment. This results in a lack of full scientific certainty about the impacts of
Prelude GHG emissions.
To be consistent with the precautionary principle, one of the guiding principles of ESD
is that the lack of full scientific certainty should not be used as a reason for postponing
measures to prevent environmental degradation if there is also a threat of serious or
irreversible environmental degradation from the action.
Considering the national and international comparisons in Table 9-69, Scope 1
emissions from the Prelude FLNG are a small portion of emission inventories, even in
the SDS. This suggests a similarly small contribution to global temperature increases
even though there is no calculable direct relationship.

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However, the reasons previously given for being unable to quantify any increase in
emissions contribution to an increase in global temperature also hold for these
comparisons. Nevertheless, the numbers presented are extremely small, meaning that
even if these estimates have orders of magnitude variance, it is still reasonable to
conclude that, holding all other factors constant, Prelude FLNG’s Scope 1 emissions’
contribution to any increase in global temperatures will be small.
Whilst Scope 1 emissions from Prelude contribute a small amount to Australian and
global GHG emissions, this fact alone does not make their impacts inherently
acceptable. The relatively small percentage of global emissions should not be used to
understate the seriousness of the threat of environmental degradation from climate
change. Rather, it clarifies the source of the threat is from global emissions quantities
rather than Prelude’s emissions. The threat of serious environmental degradation from
climate change comes from an increasing global population demanding more energy to
maintain and improve global living standards. Whilst Prelude accounts for a small
percentage of this demand, it does not create an isolated instance of a threat of serious
or irreversible environmental degradation.
Whether climate change is irreversible is even more scientifically uncertain than
predicting impacts from Scope 1 GHG emissions from Prelude for the same reasons
that made that prediction speculative. The environmental influences of variables such
as surface pressures, wind, temperature, humidity, and rainfall are added to the
variables of human adaption measures to a lower carbon economy. This is
demonstrated by the difference between the Stated Policy Scenario (STEPS) and the
SDS considered by IEA.
The key features of the Prelude FLNG production technology contributing to the
improvement of GHG performance include:
• Positioning the FLNG facility over the gas field has negated the need for a long pipeline
to shore and has reduced compression requirements during the later life of the field as
the reservoir pressure declines.
• Integrating product offloading facilities into the design of the FLNG reduces gas
compression requirements for gas export to an onshore terminal.
• Shell’s proprietary Double Mixed Refrigerant (DMR) process uses mixed refrigerant for
the pre-cooling and liquefaction cycles which allows for a flexible process to enable full
power utilisation over a wide range of ambient temperatures. The composition of the
pre-cool refrigerant can be modified to balance ambient temperature changes and cut-
point temperatures where traditional C3-MR processes cannot be adjusted in this way.
Using another option was Nitrogen Cycle, but DMR has better liquefaction efficiency.
Nitrogen Cycle can use almost double the amount of compression power to make LNG
compared to DMR technology. DMR technology means there is less fuel gas demand
and lower GHG emissions.
• Shell’s 3-stage DMR process technology rather than a 2-stage DMR process increases
the liquefaction efficiency by 8% at the expense of additional equipment required for a
3rd stage. Potentially more LNG can be produced using the same amount of power and
fuel gas which translates to the same GHG emissions for 8% more production.
• Prelude FLNG was able to increase efficiency in production by reducing cooling water
temperatures (i.e. taking colder seawater from a depth of 150 m rather than taking
seawater from surface). At this depth, the sea water supply temperature ranges
between15-23°C due to changes in tidal waves and seasons. For every degree that the
temperature of the cooling medium is colder, 0.6-0.7% of production is gained for the
same energy cost.

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Increasing levels of GHG in the atmosphere is one contributing factor to the warming of
the climate system. There is a lack of full scientific certainty about the effects of
increased emissions, but they are understood to be non-linear. The evaluation
considered that GHG emissions are among the causes of climate change, particularly if
unmitigated.
It is considered that calculating Prelude’s contribution to climate change would be
speculative and would likely provide unreliable, inaccurate, and uncertain results. As
evidence for this assertion, the evaluation has shown the substantial uncertainty in
making an evaluation stems from two equally complex and dynamic sets of
interdependent variables. The first is from predicting the contribution of Prelude GHG
emissions to a specific increase in global temperatures, and the second comes from
making a prediction of impacts on the Australian environment from the increase in
global temperatures.
In conclusion, the environmental impacts and risks arising from Scope 1 GHG
emissions from Prelude will be managed to an acceptable level because:
• GHGEM systems will be implemented in line with section 10.1.11.
• Abatement projects which improve GHG performance will be implemented on
Prelude. This, in addition to other controls outlined in section 9.11.4, will ensure
scope 1 emissions are always managed to ALARP. Further details on current in
plan abatement projects are outlined in section 10.1.11.
• Prelude will be operated to maximise reliability, availability and utilisation which
in turn delivers an optimised GHG intensity outcome along with maximising the
use of already sunk direct and indirect environmental impacts associated with the
footprint of constructing the Prelude FLNG.
Uncertainty in the assessment of impacts will be managed through the Greenhouse
Gas and Energy Management systems outlined in section 10.1.11 and the legislative
arrangements that apply to Prelude FLNG, in particular, the Safeguard Mechanism
under the NGER Act. The impacts have been assessed and will be mitigated, abated,
and (where legally required) offset.

9.11.3 Impact Assessment Summary

Table 9-71: Greenhouse Gas Emissions Evaluation of Residual Impacts
Consequence
Sensitivity
Magnitude

Residual

Environmental Receptor
Impact

Evaluation – Planned Impacts

Physical Environment -2 L Minor
Biological Environment -2 L Minor
Socio-Economic Environment -2 L Minor

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9.11.4 ALARP Assessment and Environmental Performance Standards

Much of the information collated in this ALARP assessment comes from several key documents which include the PEPCI Greenhouse Gas and Energy
Efficiency Assessment (2000-110-G000-GE-G00000-HX-7180-62106, 2012), Prelude Greenhouse Gas Fuel & Flare Policy (HSE_PRE_016332, 2020),
Energy Efficiency Assessment (2000-110-G000-GE00-G00000-HX-7180-62105) and Prelude FLNG GHGEMP (HSE_PRE_0130000, 2020).

Table 9-72: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)

Elimination Use of renewable energy (e.g. No Use of solar, wind or wave energy for a N/A
solar, wind and wave) in lieu continuously running operation does not
N/A N/A
of fossil fuels for power have the required reliability and will also
generation and marine vessel require additional space and capital
propulsion investment which are not currently
justified. Use of renewable technology for
a complete offshore LNG processing
facility is not available or technologically
proven yet. This may be further
investigated in the abatement funnel
assessment process outlined in section
10.1.11.
Elimination No flaring from routine Yes Once Prelude reaches stable operations 9.1 Prelude will have no Measured and/or calculated
operations excluding flaring flaring will make up a small percentage of planned flaring during flaring during routine operations
associated with pilot, process GHG emissions (Figure 9-27). The flare routine operations 35. balances to zero when taking
safety and non-routine events. system is a safety and loss prevention account all exclusions.

35This excludes flaring due to pilot gas and non-routine operations such as process safety reasons, shut-downs, start-ups, well clean-up, well flow tests, pigging, failed equipment pending reinstatement (e.g. passing
valves) or outstanding equipment commissioning. A baseline of ‘no routine flaring’ will be calculated once Prelude reaches steady state operations, but no later than the end of 2022.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)
system and is required for the safe 9.2 Shell will conduct a Records of the feasibility
disposal of hydrocarbons in the event of feasibility assessment on assessment and where relevant,
process upsets or emergency situations. technology for use in purchase and commissioning of
Flaring of hydrocarbon reduces the GHG assessing leaking valve equipment.
emissions in comparison to these gases quantification by the end of
being vented. 2021. If useful
Flaring during the Prelude commissioning quantification is achievable
and start-up has been significantly higher and able to be
than originally anticipated due to implemented reasonably,
unforeseen lower than expected facility this will be built into the
reliability, availability and utilization Prelude asset management
performance. Shell is inherently system for ongoing use
incentivized to maximise all three of once procured and
these areas to improve economic returns commissioned.
from the facility so there is no EPS
appropriate to include to address this.

Elimination Minimise Flaring during non- Yes During the life of the facility Prelude will 9.14 Implementation of GHG Records of measured or
routine operations have periods of non-routine operations abatement projects from calculated GHG emissions
that will require flaring. A significant focus 2021 onwards will result in abated through implementation
as Prelude moves towards steady state at least 250kt CO2-e 36 in of GHG abatement projects.
is identifying activities that will reduce reduced or avoided
flaring as much as possible during these emissions by 2025 with at
non-routine events such as trips, least 100kt CO2-e 37
shutdowns (warm and cold end) and occurring by the end of
restarts (warm and cold ends). Examples 2022.
of flaring reductions initiatives with a
focus on non-routine events to be
executed during 2020-2022 are outlined

36 On a cumulative basis between 2021-2025 inclusive.

37 On a cumulative basis between 2021-2022 inclusive.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)
in section 10.1.11. One of the most
significant example initiatives is
challenging the design minimum
turndown limits of the wells during start-
ups. Prelude has demonstrated
successfully that the minimum turndown
of the facility can handle is 15-22 mmscfd
which is significantly lower than the
design basis which was a minimum
turndown of 50 mmscfd. Although this
initiative is still being tested, during a
restart in August 2020, this control
prevented approximately 10,800 tonnes
of gas to be flared.
Elimination Reinject the acid gas into an No Based on a comprehensive assessment, N/A N/A N/A
appropriate geological no technical and/or economically viable
formation solution was identified for re-injection due
to:
• Lack of a contained and confined
geological formation to effectively
contain and seal the injected acid
gas stream. Recirculation of the CO2
through leakage back into production
fluids leading to material
compatibility issues was found to be
a possible outcome of reinjection in
the available geological strata.
• Re-injection would have resulted in
extra equipment onboard the FLNG
Facility (CO2 compression,
dehydration, extra steam boiler),
leading to additional sources of

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safety risk, emissions, congestion
and maintenance requirements.
CO2 re-injection would also have
required a considerable monitoring
(including 4D seismic) and reporting
effort to comply with Government
legislation on carbon capture and
storage, which could have introduced a
new range of environmental, safety and
operability hazards.
Subsequent to Prelude’s construction,
there are no other feasible ways to
reduce GHG emissions or improve
efficiency associated with the AGRU unit
on Prelude apart from already
implemented design controls which
include:
• Using higher efficiency solvent to
reduce hydrocarbon co-absorption
• Cold solvent pre-heated by lean
solvent leaving the regenerator.

Substitution Use of electric motor drivers No Early design considered use of variable N/A N/A N/A
or aero-derivative GTs electric motor drivers of 80MW each, with
the power demand of 200MW provided
by a bank of aero derivative gas turbo-
alternators, which are more efficient than
a steam boiler solution. Steam for
process use was to be generated by
WHRU in the GT exhaust stacks. This
arrangement was not found to be
sufficiently electrically stable, particularly
in upset and start-up conditions. Lack of

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stability would result in lost production
and extended flaring leading to more
atmospheric pollutant and GHG
emissions, thereby negating the energy
efficiency benefits achieved through the
application of GTs.
Direct drive aero derivative GTs were
also considered to improve fuel efficiency
by about 25% over the use of steam
boilers, however the design was not
mature enough to be adopted for the
Prelude FLNG.
Steam turbines were the option selected.
Seven steam boilers generate sufficient
steam to drive the main compressors and
supply 120MW. This is less energy
efficient than the other two options,
resulting in an increase in fuel use,
however is a more robust design in
terms of equipment reliability. A more
reliable Prelude implies less flaring due
to lower frequencies of unplanned
shutdowns.
Engineering Use of Shell’s proprietary Yes Shell’s proprietary DMR process uses N/A N/A – The design features N/A
DMR process in three stages mixed refrigerant for pre-cooling and of the DMR process were
liquefaction cycles which allows for a selected, installed and
flexible process to enable full power commissioned at the time
utilisation over a wide range of ambient this EP commences, and
temperatures. Shell’s 3-stage DMR are therefore not described
process technology increases the in further detail here as an
liquefaction efficiency by 8% whilst using EPS.
the same amount of power and fuel gas.

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Engineering Supply of colder seawater Yes At a depth of 150 m, the sea water N/A N/A – The design features N/A
from 150m water and use as a supply is at a temperature of 15-23°C, of the CW system were
cooling medium for main depending on tidal waves and season. selected, installed and
process For every degree that the temperature of commissioned at the time
the cooling medium is colder, 0.6-0.7% of this EP commences, and
production is gained for the same energy are therefore not described
cost. Taking this quantity of seawater in further detail here as an
150m below surface rather than at EPS.
surface is novel for FLNG from a design,
construction and installation perspective.
Prelude cannot produce without the
operation of this seawater system;
therefore, no EPS is set for its operation.
Engineering Maintenance of the flare Yes Flare flow meters, upstream of the actual 9.5 Flare flow meters will be Flare meter maintenance and
system flare boom, are maintained according to maintained in accordance calibration records.
the maintenance schedule and with the maintenance
maintenance system to ensure they are management system to
within reliability, availability and accuracy ensure they meet required
requirements for this equipment. This reporting accuracy needed
enables accurate measurement of flare for NGER.
GHG emissions and associated VOC’s.
Since Prelude is now in continuous
operation, there is no practical way to
maintain the operating flare tip as at a
minimum the pilot flare is ignited at all
times. The flare system has been
designed to operate in this manner.
Engineering Design of flare and AGRU Yes The flare boom design has been 9.6 No recorded flare flame Incident records of flare flame
vent system optimized to optimized to minimise the risk of a flare outs which is not out events where auto ignition
minimise the risk of flare flame out. Avoiding flare flame outs immediately auto-ignited. has not occurred.
flame-out to a tolerable level. minimises both air emissions and GHG
emissions as flare combustion avoids the

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release of potentially harmful GHGs like
methane and air pollutants like VOC’s.
There have been no flare flame out since
Prelude commenced operations.
Prelude’s flare is fitted with ignition
control to spark the flame as soon as
flame out is detected.
Engineering Minimise use of diesel during Yes This reduces GHG emissions associated 8.2 Limit boilers running on Daily report
start up and shutdowns by with re-start of the Prelude FLNG. diesel to periods when fuel
using boil off gas or vaporised gas is not able to
LNG where possible reasonably be used
including periods such as
start-up and shut down.
Engineering Maximise efficiency of pumps Yes This control has been implemented on N/A N/A - This design feature is N/A
(U00000) Prelude to inherently reduce GHG not appropriate to have a
emissions and increase energy performance standard set
efficiency. against it.
Engineering All control valves to be Yes This control has been implemented on N/A N/A - This design feature is N/A
specified 'low emission' type Prelude and is accurate as of the time not appropriate to have a
(U00000) the facility was in detailed design. performance standard set-
up against it.
Engineering Minimise heat loss through Yes This control has been implemented on N/A N/A - This design feature is N/A
insulation. Insulation used is Prelude and is accurate as of the time not appropriate to have a
the same as on onshore plant the facility was in detailed design. performance standard set-
however due to the compact up against it.
nature of Prelude, the piping
run length and consequently
heat loss is much less
(U00000)
Engineering Use of LNG expanders to Yes This control has been implemented on N/A N/A - This design feature is N/A
produce an isentropic Prelude and is accurate as of the time not appropriate to have a

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pressure drop for the LNG the facility was in detailed design. It performance standard set-
and refrigerant fluids improves the efficiency of the production up against it.
(U14000) process, therefore reducing GHG
emissions.
Engineering NGL Recompressor and Yes This control has been implemented on N/A N/A - This design feature is N/A
expander turbo expander Prelude and is accurate as of the time not appropriate to have a
(U14000) the facility was in detailed design. It performance standard set-
improves the efficiency of the production up against it.
process, therefore reducing GHG
emissions.
Engineering Heat Exchangers printed Yes This control has been implemented on N/A N/A - This design feature is N/A
circuit and coil wound heat Prelude and is accurate as of the time not appropriate to have a
exchangers to increase the facility was in detailed design. performance standard set-
efficiency (U14000) up against it.
Engineering Make the steam condensate Yes This control has been implemented on N/A N/A - This design feature is N/A
line downstream of the MR Prelude and is accurate as of the time not appropriate to have a
and PMR Steam turbines the facility was in detailed design. performance standard set-
negative pressure to increase up against it.
the efficiency of the turbines
(U14000)
Engineering End Flash Compressor and Yes This control has been implemented on N/A N/A - This design feature is N/A
Motor Driver - Make motor Prelude and is accurate as of the time not appropriate to have a
driver variable speed the facility was in detailed design. It performance standard set-
(U14000) improves the efficiency of the production up against it.
process, therefore reducing GHG
emissions.
Engineering End Flash unit - Prior to use of Yes This control has been implemented on N/A N/A - This design feature is N/A
end flash gas as fuel, use the Prelude and is accurate as of the time not appropriate to have a
low temperatures in the end the facility was in detailed design. It performance standard set-
flash gas to liquefy natural gas improves the efficiency of the production up against it.
(U14000)

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process, therefore reducing GHG
emissions.
Engineering HP Steam Boiler Steam Force Yes This control has been implemented on N/A N/A - This design feature is N/A
Draught Fan (U40000) - select Prelude and is accurate as of the time not appropriate to have a
a high efficiency technology the facility was in detailed design. performance standard set-
for fans (U14000) up against it.
Engineering Flare headers - Nitrogen Yes This control has been implemented on N/A N/A - This design feature is N/A
purging rather than fuel gas Prelude and is accurate as of the time not appropriate to have a
purging (U63000) the facility was in detailed design. This performance standard set-
reduces the amount of gas combusted on up against it.
the facility, therefore reducing GHG
emissions.
Engineering Increasing the steam system No Increasing the temperature and pipe N/A N/A N/A
pipe class above 900 pounds class above 900 pounds in the steam
(U63000) system would significantly reduce the
amount of energy input required for the
system. However, increasing the pipe
class above 900 pounds would mean
much higher CAPEX, weight of piping
and HSE risks. The sum of these costs
was considered greater than the possible
benefits in energy efficiency that can be
achieved.
Engineering Decrease the condensing No Although the condensing pressure of the N/A N/A N/A
pressure of steam to below condensing steam turbines is at the
200mbar (U63000) lowest that can be achieved with the
designed cooling system, further
efficiencies could be achieved by
increasing the size of the cooling system.
However, this would be a significant
change in the cooling system and was
rejected because further study costs

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were considered too high at the time of
design.
Engineering Increase thermal efficiency of No An opportunity was raised during design N/A N/A N/A
the boilers to consider maximising the Thermal
Efficiency of Boilers. On investigation, it
was found that the boilers’ thermal
efficiency could be increased from 90%
to 93% by increasing the size of the
economisers. Increasing the thermal
efficiency above 93% would require
additional equipment meaning a
significant increase in size, weight and
cost and hence increasing the efficiency
above 93% was rejected early in the
investigation. A financial assessment was
then carried out, which demonstrated a
net benefit to increasing the efficiency
from 90 to 93%. However, to obtain this
increase in efficiency it is necessary to
reclaim a greater amount of energy from
the exhaust gas. This was found to lead
to an increase in the risk of acid
corrosion of components occurring during
commissioning (from sulphuric acid in
diesel exhaust). This risk was considered
significant enough to reject the
opportunity and maintain the design
efficiency at 90%.
Engineering Change all electrical motors No An opportunity was identified to consider N/A N/A N/A
>1 MW to VSD. changing all large motors (over 1MW) to
Variable Speed Drivers (VSD) in order to
increase their efficiency in reacting to low
flows. Although, it has been registered as
‘rejected’ on the basis that not all large

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motors are fitted with Variable Speed
Drivers, it could be considered as partly
implemented as those large motors
where a significant benefit in applying
variable speed exists have been changed
to steam turbines. The MEG Recycle
Pumps, Overhead Compressor Driver
and Endflash Compressor Driver are all
Steam Turbines in the design. Other
pumps over 1MW have minimal variation
in flow, so there is little benefit in making
them variable speed.
Engineering Replace boilers with No The Prelude FLNG heat and power N/A N/A N/A
cogeneration combined cycle. system is based on boilers and steam
turbines as opposed to a Co-Generation
or Combined Heat and Power plant. This
decision has the biggest individual impact
on GHG output with Combined Heat and
Power Plants up to 1/3 more efficient
than boiler based systems. However, at
the time of design, Co-Generation and
Combined Heat and Power were
relatively new technologies and were
considered to carry significant technology
risks. Given the level of technical novelty
already incorporated into the FLNG
design, and the costs in terms of risks
were considered greater than the
benefits in energy efficiency that could be
achieved at the time of design.
Administrative Prelude Operations Playbook Yes Prelude’s Operations Playbook provides 9.7 The Prelude Operations Prelude Operations Playbook
and provides fuel model guidance a guide and aims to achieve an optimised Playbook is available and
to minimise GHG emissions process shutdown and start up sequence provides panel operators
to minimise process upsets and reduce the recommended optimum

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Procedural during planned plant loss of hydrocarbon inventory to flare and fuel mode during planned
Controls shutdowns and start-ups. acid gas venting. This playbook has been plant shutdowns and start-
updated regularly during the start-up ups to achieve GHG
phase to optimise the start-up process reduction.
and address issues which have resulted
in increased flaring. It is continually
updated through learning from the early
phase operations and as new
opportunities are identified to improve
efficiency or minimise flaring.
Administrative Report annually the calculated Yes This is a regulatory requirement under N/A N/A N/A
and GHG Emissions and Energy the NGER Act 2007.
Procedural to the Clean Energy Because NGER reporting is a regulatory
Controls Regulator. requirement, no EPS has been
developed for this requirement.
The Safeguard Mechanism baseline is a
requirement that needs to be met. The
Safeguard Mechanism sets a GHG
baseline for the Prelude FLNG. Any
exceedance is required to be offset
through the purchase of ACCUs..
Administrative Fugitive emission design Yes Fugitive emissions are those emissions 9.8 Undertake targeted topside Records of leak detection and
and controls that occur from leaks from valves, fugitive emissions / general repair survey and associated
Procedural flanges from any hydrocarbon processing leaks survey on an annual maintenance repair records
Controls areas of the plant. Fugitive emissions basis, when operating, and where relevant.
make up <1% of the GHG emissions repair identified leaks in
from the facility. line with the maintenance
As outlined in the Prelude Environment management system
Basis of Design, fugitive emissions on where it is ALARP to do so.
Prelude FLNG shall be significantly
reduced by the following adopted
controls:

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• Use of valves with bellow or
double packing seals or equally
efficient equipment;
• Magnetically driven or canned
pumps, or pumps with double
seals and a liquid barrier;
• Minimisation of the number of
flanges;
• Closed sampling systems;
• Drainage of containment
effluents in closed system;
• Use of relief valves instead of
open vents in tank roofs; and
• Use of pumps with double
mechanical seals must be used
for all substances, except inert
liquid.
This is demonstrated effective during the
operation of Prelude by the results of the
most recent LDAR surveys. The last
survey completed in second half of 2019
found 7 leaks up to a maximum leak rate
of 34% Lower Explosive Limit @ 100mm.
This is a low amount of detected leak
sources given the amount of potential
leak sources on Prelude FLNG. This
result also suggests that actual fugitive
emissions are currently lower than
predicted during design. All topside
hydrocarbon containing modules on
Prelude are surveyed for fugitive

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emissions at least once per year whilst in
production.
Shell Group has a target to maintain
methane emissions intensity below 0.2%
by 2025 38. This target covers all oil and
gas assets for which Shell is the operator
and therefore includes Prelude. The
objective of the Prelude Methane
Improvement Plan (MIP) is to improve
methane emissions reporting, focusing
on reducing uncertainty associated with
methane emissions quantification. This
will facilitate prioritisation of methane
emission sources for targeted abatement
projects. Fugitive (general leaks)
methane sources are being addressed
via comprehensive LDAR program.
Specific actions aimed at reducing
methane emissions for Prelude include:
1) annual abatement project identification
and assessment process (first workshop
occurred in November 2020). 2)
GHGEMP with emissions intensity and
abatement targets linked to asset
performance scorecard, required annual
deliverable. MIP to be included in an

38
For more information see: https://www.shell.com/energy-and-innovation/natural-gas/methane-
emissions/_jcr_content/par/textimage_438437728.stream/1587995196996/53beef2f8ba2e90560c074f56552e2acfe30582b/shell-methane-case-study.pdf

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Annex of the GHGEMP. 3) Asset
Quarterly Performance Appraisal (QPA)
conducted and assessment of progress
of MIP deliverables and abatement
projects are tracked quarterly.
Administrative Carbon and Energy Yes A CEMIS, which is a three tier (plant, unit 9.9 Commence monitoring Records demonstrating CEMIS
and Management Information and equipment level) operational plant energy performance has been implemented
Procedural Systems (CEMIS) performance system available to the within 18 months of
Controls panel operator which provides them with completion of all relevant
a “live” monitoring of plant, unit and performance tests for
equipment performance. This system specified plant equipment
compares actual performance against a but no later than the end of
set of value drivers at equipment or unit 2024.
level to optimise the plant operational
and GHG emissions performance.
Specified plant includes:
- AGRU
- NGL Extraction and Liquefaction
- Steam and Power
- Flaring and Venting
Engineering, Greenhouse Gas and Energy Yes Prelude has a GHGEM System which 9.10 Abatement opportunities in Greenhouse Gas and Energy
Administrative Management (GHGEM) includes a GHGEMP, which receives and and out of plan are Management Plan
and System including Greenhouse incorporates key inputs from the identified and summarised
Procedural Gas and Energy Management abatement assessment and OP within GHGEMP from 2021
Controls Plan (GHGEMP), Abatement processes (Refer section 10.1.11). revision onwards.
Workshop and Assessment The annual abatement workshop and
Process, OP Process and assessment process will ensure that
Fuel and Flare Forum further detailed assessment of additional

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emission reduction opportunities is 9.8 Undertake targeted topside Records of leak detection and
undertaken and will ensure impacts from fugitive emissions / general repair survey and associated
GHG emissions are reduced to ALARP leaks survey on an annual maintenance repair records
on an ongoing basis. basis and repair identified where relevant.
The GHGEMP is reviewed annually to leaks in line with the
incorporate the regular review and maintenance management
optimisation processes that occur, system where it is ALARP
namely the abatement workshop and to do so.
assessment process and subsequent OP
process, which sets out integrated GHG 9.11 Conduct annual abatement Records of the GHG abatement
targets for the Prelude FLNG. The full assessment process as assessment process.
GHGEM system is further described in outlined in section 10.1.11.
section 10.1.11.

9.12 GHG (total emissions, GHGEMP and records of

intensity and abatement) monthly GHG target tracking with
targets will be set and the Prelude asset leadership
tracked on a monthly basis team.
(quarterly for abatement) to
ensure GHG emissions are
ALARP on an ongoing
basis.
9.13 Implementation of GHG Records of measured or
abatement projects from calculated GHG emissions
2021 onwards will result in abated through implementation
of GHG abatement projects.

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at least 250kt CO2-e 39 in
reduced or avoided
emissions by 2025 with at
least 100kt CO2-e 40
occurring by the end of
2022.

9.14 In the event trending of Records demonstrating proactive

GHG emissions is reliably action is taken in order to reduce
forecast to risk exceeding GHG emissions to ALARP.
2.95 Mt CO2-e, proactive
action will be taken in order
to ensure GHG emissions
are reduced to ALARP,
thus providing the highest
likelihood of not exceeding
2.95Mt CO2-e in a year.
9.15 Asset surveillance Records demonstrating trending
engineering will carry out of GHG emissions and
trending of GHG emissions implemented abatement projects
and implemented occurs at least a quarterly basis.
abatement projects on at
least a quarterly basis in
order to track progress
towards meeting set
targets and GHG EPOs.

39 On a cumulative basis between 2021-2025 inclusive.

40 On a cumulative basis between 2021-2022 inclusive.

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9.16 In the event emissions in Records demonstrating a review

any year exceed 2.95Mt of ALARP assessment was
CO2-e, review the risk carried out and that records
assessed GHG ALARP demonstrate emissions are still
items on the fuel and flare be managed to ALARP.
register to expedite
activities to limit further
emissions to ALARP.

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9.11.5 Acceptability of Impacts

The assessment of risks from GHG emissions associated with the Prelude project has
been considered in the following context.

• Defined acceptable level of GHG emissions set for Prelude

• Principles of ESD

• Relevant requirements

• Significant impacts to MNES

• Internal and external context.

Prelude’s Defined Acceptable Level of GHG Emissions

Gross scope 1 GHG emissions are an inherent feature of Prelude operations. Gross
scope 1 emissions from Prelude will not exceed 2.95 Mt of CO2-e in a calendar year, on
an aggregate basis. Over the next five years, between 2021 and 2025, Prelude’s
average GHG emissions will not exceed 2.6 Mt of CO2-e and this represents a defined
acceptable level of emissions. Acceptability is considered in light of:
• the development concept for Prelude that was constructed was assessed to be ALARP
at the time of completing detailed design. In addition, Shell recognises that Prelude
scope 1 emissions must be reduced to ALARP on an ongoing basis in order to be
acceptable. An ALARP assessment of Prelude’s GHG emissions is outlined in section
9.11.4 and abatement projects that improve GHG performance will be implemented on
Prelude. Shell will demonstrate emissions will be reduced to ALARP on an ongoing
basis through implementation of key GHGEM processes outlined in section 10.1.11.
Implementation of GHG abatement projects from 2020 onwards will result in at least
250kt CO2-e in reduced or avoided emissions by 2025 with at least 100kt CO2-e
occurring by the end of 2022;

• the level of GHG emissions for Prelude is consistent with design GHG emission
predictions for the facility from 2011/12;

• Prelude will be operated to maximise reliability, availability and utilisation which in turn
delivers an optimised GHG intensity outcome along with maximising the use of already
sunk direct and indirect environmental impacts associated with the footprint of
constructing the Prelude FLNG;

• the forecast GHG emissions represent a reasonable basis as outlined in section

10.1.11; and

• the level accounts for about 100kt CO2-e uncertainty of Prelude FLNG emissions
throughout its operating life, which is inherent in forecasts and future investment
decisions.

Principles of ESD
The Prelude FLNG GHG emissions are consistent with the principles of ESD. Of
particular note is the principle of inter-generational equity – that the present generation
should ensure that the health, diversity and productivity of the environment is maintained
or enhanced for the benefit of future generations. Prelude demonstrates it meets this
principle through ensuring GHG emissions do not exceed the defined acceptable level

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and by ensuring significant GHG abatement targets are achieved. In addition, the risks
and impacts from GHG emissions from Prelude are consistent with the Paris Agreement
and principles of ESD based on:
• meeting existing end-user demand for energy;

• facilitating the distribution of lower carbon energy to meet the UN Sustainable Development
goals, in particular;

o affordable and clean energy;

o climate action;

o no poverty; and

o decent work and economic growth.

• the precautionary principle has been applied, and mitigation measures have been adopted in
the absence of full scientific certainty;

• global policies and actions related to GHG emissions have been considered and Australian
legislation supports these policies and will be complied with, as noted further below;

• the Prelude EIS has been subject to public comment and regulatory scrutiny which ensures
the broadest community of people have been involved in management of issues that affect
them. In addition, relevant persons have been consulted in the preparation of this EP. No
objections or claims relevant to GHG emissions were raised by relevant persons during
consultation; and

• the decision making process on production technology has effectively integrated both long-
term and short-term economic, environmental, social and equitable considerations

This will be sustained throughout the life of the Prelude FLNG through inclusion of GHG
minimisation and energy efficiency as selection criteria along with other technical and
monetary considerations in implementing the GHGEM processes outlined in section
10.1.11 to ensure GHG emissions are reduced to ALARP and acceptable levels on an
ongoing basis.
Significant Impacts to MNES
There is no clear and convincing evidence that GHG emissions from the Scope 1 GHG
emissions from Prelude will result in significant impacts to threatened or migratory
species (refer section 9.11.2). The impacts and risks from the GHG emissions aspect
of the Prelude FLNG on the Commonwealth marine environment do not exceed any of
the significant impact criteria for any MNES. However, given the lack of full scientific
certainty, GHG emissions will be managed to ALARP and acceptable levels on an
ongoing basis.
Relevant Requirements
The legislative frameworks for managing impacts from Prelude FLNG’s GHG emissions
are well-developed and comprehensive because they cover prevention, abatement,
and offset of emissions in a structured and predictable way. In the operation of Prelude,
Shell complies with and commits to continued compliance with the mechanisms
implemented in Australia to achieve the goals of the Paris Agreement.

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Australia has committed to a NDC under the Paris Agreement to reduce emissions by
26-28% below 2005 levels by 2030. The Commonwealth government’s plans to
achieve this commitment have included recognition of emissions associated with new
LNG projects in Australia, including Prelude.
Australia’s commitments under the Paris Agreement are delivered through a range of
policies and initiatives, with the primary legislation for emissions management being the
NGER Act. The NGER Act provides a single, national framework for the reporting and
distribution of information related to GHG emissions, GHG projects, energy production
and energy consumption to meet the following objectives:
• inform government policy;

• inform the Australian public;

• help meet Australia's international reporting obligations;

• assist Commonwealth, state and territory government programmes and activities, and

• avoid duplication of similar reporting requirements in the states and territories.

Under the NGER Act facility operators are required to report on direct GHG emissions,
energy production and energy consumption, enabling the capture of data on energy flows
and transformations occurring throughout the economy. The NGER Act is aligned with
the GHG Protocol in defining Scope 1 and 2 emissions.
The safeguard mechanism provides a framework for Australia’s largest emitters to
measure, report and manage their emissions. It was established to ensure that emissions
reductions delivered through the Emissions Reduction Fund are not displaced
significantly by GHG emissions over and above business-as-usual- levels elsewhere in
the economy 41. It does this by requiring large facilities, whose net emissions exceed the
safeguard threshold of 100,000 tonnes of CO2-e per annum, to keep their net emissions
at or below emissions baselines set by the Clean Energy Regulator. Key elements of
the mechanism include:
• safeguard facilities must meet the reporting and record keeping requirements of the
NGER Act, including the Clean Energy Regulator’s requirements for audits prior to
baseline setting or to check compliance management;

• if a safeguard facility is likely to exceed its baseline, the responsible emitter must act,
including by purchasing and surrendering Australian Carbon Credit Units (ACCUs) to
offset excess emissions; and

• penalties for non-compliance.

Under the Commonwealth government’s framework for management of Scope 1 and 2

emissions in Australia Shell reports as a corporate group under the NGER Act and as
the entity with “operational control” of the Prelude FLNG facility, this includes emissions
from Prelude.
Shell has complied with and will continue to comply with the contemporary
requirements as defined under the NGER Act and associated Safeguard Mechanism

41
Explanatory Statement, NGER (Safeguard Mechanism) Rule 2015

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(including any future amendments or changes in law). In summary this will require
Shell to:
• complete and submit annual NGER reports for the Kyoto Protocol listed (or applicable post-
Kyoto agreement at the time of operations) GHG emissions on a CO2 equivalency basis (as
defined in Section 9 of the NGER Act and NGER Regulations 2008) by fuel type, and the
relevant requirements of the NGER (Safeguard Mechanism) Rule 2015;

• comply with the Safeguard Mechanism baseline set for the Prelude FLNG which is currently
2,725,687 tCO2-e; and

• if the Safeguard Mechanism baseline for Prelude is exceeded, follow requirements outlined
under the Safeguard Mechanism. This may require Shell to purchase and surrender
ACCUs.

Regarding the NGER Act, the Safeguard Mechanism baseline could be used as a proxy
for what the Australian Government has deemed to be an acceptable level of emissions
from a given project. Oversight is provided by the Clean Energy Regulator audit
processes, and there are reasonable penalties associated with exceedances. This
creates an incentive for Shell to keep emissions within the established baseline.
However, Shell recognises that the Safeguard Mechanism is a regulatory reporting
requirement that may be interpreted as an accounting approach rather than remaining
focussed on environmental acceptability criteria, and therefore does not by itself deliver
a reduction in emissions.

Internal and external context

Shell Australia, as part of the wider Shell Group, is playing a role in working towards
larger, group-level ambitions to be a net zero emissions energy business 42 by 2050,
and sooner if that is possible, in step with society and our customers.
The context for the Shell Group ambition was the recognition that for society to achieve
a 1.5 degrees Celsius future in line with the Paris Agreement, the world is likely to need
to stop adding to the stock of GHG in the atmosphere – a state known as net-zero
emissions – by around 2060. But those who can move faster, must move faster –
advanced parts of the world are likely to need to reach that point by 2050.
Shell Group currently proposes to work towards this ambition in three ways, in step
with society:
• an ambition to be net zero on all the emissions from the manufacture of all its products
(scope one and two) by 2050 at the latest;

• accelerating Shell Group’s Net Carbon Footprint ambition to be in step with society’s aim to
limit the average temperature rise to 1.5 degrees Celsius in line with the goals of the Paris
Agreement on Climate Change;

42Asof the date of this document Shell Group’s operating plans and budgets do not reflect Shell Group’s
Net-Zero Emissions ambition. Shell Group’s aim is that, in the future, its operating plans and budgets will
change to reflect this movement towards its new Net-Zero Emissions ambition.

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• aiming to help its customers decarbonise. That means working with customers to address
the emissions which are produced when they use the fuels they buy from Shell Group. That
effort includes working with broad coalitions of businesses, governments and other parties,
sector by sector, to identify and enable decarbonisation pathways for each sector.

Shell Group’s aim is that, in the future, its operating plans will change to reflect this net
zero ambition.
Examples of current Shell Group-level initiatives aimed at addressing uncertainty and
contributing to society achieving the goals of the Paris Agreement targets are:
• unconditional three-year target (to 2022) to reduce its Net Carbon Footprint 43 against the
2016 baseline by 3-4%, linked to remuneration for more than 16,500 staff. It is intended that
this target setting will be done annually, with each year’s target covering a three-year
period;

• continued growth of the New Energies business, having already invested in a range of low-
carbon technologies, from biofuels, hydrogen and wind power, to electric vehicle charging
and smart energy storage solutions;

• monitoring and reporting on Shell Group performance. Every five years, the Shell Group
proposes to assess collective progress toward meeting the Paris Agreement’s long-term
goal informed by the agreement’s five-yearly "global stocktake". Shell Group will review its
ambition based on this assessment of progress, revised scenarios, and nationally
determined contributions. Inherent in this review will be an appraisal of developments in
technology and policy. The first five-year review is currently anticipated to take place after
2021;

• developing scenarios. Shell Group has been developing possible visions of the future since
the 1970s. Shell Scenarios 44 ask, “what if?” questions encouraging leaders to consider
events that may only be remote possibilities and stretch their thinking. These scenarios also
help governments, academia and business in understanding possibilities and uncertainties
ahead. For example, Shell has built a scenario looking at what the EU might do to
decarbonise energy in the next 30 years. It explores a possible, but highly demanding
pathway to help achieve a climate-neutral EU by 2050 – including deployment of clean
technologies and shifting choices to support a green economy.

Shell Group’s business plans will change over time in step with society's progress
towards meeting the Paris Agreement. Further information and examples of how the
Shell Group is playing a role in the energy transition is available on the website
(www.shell.com).

43 Shell Group’s “Net Carbon Footprint”, includes Shell Group’s carbon emissions from the production of its energy
products, its suppliers’ carbon emissions in supplying energy for that production and its customers’ carbon emissions
associated with their use of the energy products it sells. Shell Group only controls its own emissions. The use of the term
“Net Carbon Footprint” is for convenience only and not intended to suggest these emissions are those of Shell Group or
its subsidiaries.

44These scenarios are a part of an ongoing process used in Shell Group for over 40 years to challenge executives’
perspectives on the future business environment. They are designed to stretch management to consider even events that
may only be remotely possible. Scenarios, therefore, are not intended to be predictions of likely future events or outcomes.

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Shell Australia, as operator of Prelude is playing a role in working towards the larger
group-level ambitions, for example by:
• setting performance outcomes which result in significant GHG abatement between 2021
and 2025 (see section 9.11.6); and

• providing natural gas to customers to help them lower their own emissions by displacing
other higher carbon intensity energy sources.

Shell’s ongoing consultation program will consider statements and claims made by
stakeholders when undertaking the assessment of impacts and risks. Shell has also
considered the internal context, including Shell’s environmental policy and corporate
requirements (as further outlined in section 10.1.11). The environmental performance
outcomes, and the controls which will be implemented, are consistent with the outcomes
from stakeholder consultation for the Prelude FLNG facility and Shell’s internal
requirements.
Acceptability Summary
As outlined above, the acceptability of the impacts and risks from GHG emissions from
Prelude operation have been considered and found to be acceptable in the context of:

• Defined acceptable level of GHG emissions set for Prelude

• The principles of ESD

• Relevant requirements

• Significant impacts to MNES

• Internal and external context

9.11.6 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

The maximum gross scope 1 emissions limit from Calculated GHG emissions reported on calendar
the Prelude FLNG will not exceed 2.95 Mt CO2-e in year basis (aggregate).
any given year, on an aggregate basis.

Over the next five years of operation (namely Calculated GHG emissions reported on calendar
2021 – 2025), GHG emissions will not exceed 2.6 year basis.
Mt CO2-e, on average.

Implementation of GHG abatement projects from Calculated GHG emissions abated on a calendar
2021 onwards will result in at least 250kt CO2-e 45 year basis through implementation of GHG
in reduced or avoided emissions by 2025 with at abatement projects.
least 100kt CO2-e 46 occurring by the end of 2022.

45 On a cumulative basis between 2021-2025 inclusive.

46 On a cumulative basis between 2021-2022 inclusive.

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9.12 Waste Management

9.12.1 Aspect Context

Many activities on the FLNG and supporting vessels results in the generation of a
variety of hazardous and non-hazardous waste streams. Non-hazardous wastes
include domestic and industrial wastes, such as aluminium cans, bottles, paper and
cardboard and scrap steel. Hazardous wastes include oil contaminated materials (e.g.
sorbents, filters and rags), amine waste, spent chemical containers, paint solvents and
containers, light tubes and batteries. Sand and sludges may also be generated during
well clean-up operations and process vessel maintenance. All wastes generated (other
than permitted waste discharge streams addressed elsewhere within this EP) are
transported to shore for reuse, recycling, treatment or disposal by a licensed waste
contractor. Note that any waste management and disposal within international
jurisdictions is out of scope of this EP.
The management of wastes will not result in any planned impacts to the offshore
marine environment given there is no planned release; however, improper storage and
handling of wastes may result in accidental losses to the marine environment. These
unplanned events may result in impacts to the marine environment. Shell’s extensive
operational experience indicates most accidental releases of wastes to the marine
environment are typically relatively small scale and infrequent events.
Low level Naturally Occurring Radioactive Materials (NORMs) may also occur in
sludges, scale and sands typically associated with the inlet/separator facilities, filters
and low points within the hydrocarbon processing system. The NORM nuclides of
primary concern in oil and gas production are Radium-226 and Radium-228. These
decay into various radioactive progeny, before becoming stable. Radium-226 and
Radium-228 belong to the two principal radioactive decay series associated with
NORMs in the oil and gas industry (Uranium-238 and Thorium-228 respectively)
(APPEA 2002 and IOGP 2008). Such waste streams are removed from the facility for
appropriate treatment/disposal onshore.
During process related maintenance activities and opening of vessels, potentially
mercury-contaminated guard beds, materials, filters, sludges and sands may also be
recovered. As with other hazardous wastes, these will be assessed, handled and
stored appropriately and sent to shore for proper disposal.
Waste segregation is established and maintained through the provision of labelled bins,
skips or other appropriate receptacles used to comingle similar waste streams in
accordance with their classification to realise efficiencies in storage, transport,
treatment, recycling and/or disposal.
There are a number of dedicated and secondary/contingency waste storage areas on
the FLNG facility to ensure there is sufficient capacity for all anticipated activities and
phases of the activity. Waste storage on the FLNG facility has a capacity to
accommodate approximately 14 days of waste accumulation during normal operations.
Waste storage areas are described further in the Prelude FLNG Waste Management
Procedure (HSE_PRE_010753). Additional temporary laydown areas for waste storage
may be established during specific campaigns as required, e.g. during major
maintenance. Waste receptacles are back loaded onto supply vessels via crane for
transportation to onshore facilities.

9.12.2 Description and Evaluation of Impacts and Risks

Physical Environment
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Improper management of hazardous or non-hazardous wastes and/or accidental

release may result in pollution of and contamination in the marine environment via
reduction in water and sediment quality. This may result in toxic effects, however given
the dynamic nature of the offshore receiving environment and the small nature and
scale of most potential waste spills/releases, any such effects will be of short duration
and highly localised. The implications to potentially sensitive receptors due to a
reduction in water and sediment quality are discussed further in the Biological
Environment assessment below and are not assessed further in the context of the
physical environment.
Biological Environment
There is the potential for impacts on marine fauna that may interact with wastes, such
as packaging and binding, should these enter the ocean as marine fauna can become
entangled and waste plastics can be ingested when mistaken as prey (Ryan et al.
1988). Marine debris has been identified as a threat for a range of vertebrate fauna
species, including marine turtles, birds, marine mammals and sharks and rays. Marine
debris is listed as a key threatening process under the EPBC Act. Persistent wastes
such as plastics are of particular concern, as the threat to fauna may remain long after
the waste is released. Potential impacts of marine debris on key fauna species include
(DEWHA 2009c):
• Entanglement, potentially resulting in restricted mobility, drowning, starvation,
smothering and wounding
• Ingestion (particularly of plastics) leading to physical blockage of digestive systems,
leading to starvation
• Acute or chronic toxic effects.
Plastic debris can also act as a concentrator of Persistent Organic Pollutants (POPs)
that occur universally in seawater at very low concentrations as they get picked up by
meso/microplastics via partitioning. The hydrophobicity of POPs can facilitate
concentration in the meso/microplastic litter at a level that is several orders of
magnitude higher than that in seawater. When ingested by marine species,
contaminated plastics present a credible route by which the POPs can enter the marine
food web.
NORMs are comprised of radioactive elements such as uranium, radium and radon,
and are often present at very low concentrations during normal reactions between
water and rock. The associated environmental risk is incorrect disposal of waste
containing NORMs, leading to pollution of the ocean and potentially chronic and acute
toxicity impacts on marine flora and fauna. Inappropriate storage, handling or disposal
may also impact on human health (depending on the composition of the NORMs) if the
workforce are exposed to the material, however this aspect is managed via the Safety
Case regime. To be classified as hazardous radioactive material from a waste
management perspective, the applicable Threshold Activity Concentration Limits
(TACL) must be exceeded as defined by the relevant state and/or federal regulations.
The TACL is the upper level of radioactivity prescribed by the Statutory Authority below
which material may be classified as Radiological Non-Hazardous. Disposal of materials
that do not exceed the defined TACL may be carried out as per general non-hazardous
waste.
Habitats within the Operational Area are not considered to be particularly sensitive or of
high conservation value and are well represented in the region. Given the typically
small volumes of wastes that may be released during any given event, potential

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impacts to sensitive species are expected to be restricted to individual animals. Many

of the vertebrate species considered vulnerable to waste impacts occur seasonally or
are expected to occur in low densities (e.g. transiting the area).
Apart from waste streams that are permitted for discharge in accordance other sections
of this EP, there are no other planned waste discharges from the FLNG facility or
support vessels. Given that any direct impacts from unplanned events to receptors in
the offshore environment are likely to be localised and short-term, the residual risk of
waste release is assessed to be Dark Blue as per Table 9-73.

9.12.3 Risk Assessment Summary

Table 9-73: Waste Evaluation of Residual Risks

Residual Risk
Consequence

Likelihood
Environmental Receptor

Evaluation – Unplanned Risks

Physical Environment N/A N/A N/A

Biological Environment Slight C Dark Blue

Socio-Economic Environment N/A N/A N/A

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9.12.4 ALARP Assessment and Environmental Performance Standards

Table 9-74: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Performance Measurement Criteria
Controls Standard (EPS)

Elimination N/A N/A Waste generation cannot be eliminated from N/A N/A N/A
the offshore facilities.
Substitution N/A N/A The use of alternative materials which will N/A N/A N/A
produce less wastes is part of the Product
Stewardship Standards of Shell.

If materials that generate less wastes are

identified in the future, these will undergo
appropriate assessment.
Engineering Designated Waste Storage Areas Yes Wastes are properly stored, secured, 10.1 Designated waste storage Assurance against waste
available on Prelude. adequately contained and transported to facilities on Prelude is management facilities,
avoid the risks of accidental overboard available to enable waste to equipment and practices
discharge or release, especially during be secured and stored on demonstrates that
adverse weather. facilities. appropriate waste storage
facilities have been
provided and maintained.
The Prelude FLNG Waste Management
Procedure ensures the cradle-to-grave
management of wastes as required by the
Shell HSSE Control Framework Manual on
Waste Management.
Administrative Prelude FLNG and required Yes Prelude FLNG and each required marine 10.2 Prelude FLNG and marine Garbage Management
and Procedural marine support vessels will support vessel has its own Garbage support vessels (to which Plan (or equivalent) is
Controls maintain a Garbage Management Management Plan/Procedure (or equivalent) MARPOL Annex V / Marine sighted onboard Prelude
Plan (or equivalent) as relevant to manage wastes generated and stored Order 95 applies) have a FLNG and marine support
to vessel class, type and size. onboard. All wastes that are not permitted for vessels and are
discharge are sent ashore for reuse, maintained up to date.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Performance Measurement Criteria
Controls Standard (EPS)
treatment, recycling and/or disposal as current Garbage Management
appropriate. This control measure is in Plan (or equivalent) 47.
accordance with Protection of the Sea
(Prevention of Pollution from Ships) Act 1983 10.3 Prelude FLNG and marine Garbage record book
and AMSA Marine Order 95. support vessels to comply maintained for Prelude
with AMSA marine order 94 & FLNG and marine support
95 (marine pollution vessels as per Marine
prevention – packaged Order 95 demonstrates
harmful substances/garbage), that there were no
specifically: unpermitted discharges of
solid waste as part of the
• No planned disposal of petroleum activities 48.
domestic waste, solid
wastes or maintenance
wastes overboard from
vessels (other than
planned discharges
permitted by this EP).

Administrative Environmental awareness Yes All employees and contractors working on or 10.4 FLNG and vessel-based EP training records
and Procedural training for personnel in connection with Prelude with defined personnel are aware of waste
Controls responsibilities to fulfil as part of the EP are management requirements to
required to attend EP training that is formally avoid accidental losses of
tracked. The EP training covers waste waste to the marine
management (Section 10.3.2). environment through the EP
training.

47 Advice from the Recognised Organisation will be followed where there is any variation to the this EPS for the Prelude FLNG.

48 Advice from the Recognised Organisation will be followed where there is any variation to the this measurement criteria for the Prelude FLNG.

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9.12.5 Acceptability of Impacts

Table 9-75: Acceptability of Impacts – Waste Management
Receptor Receptor Acceptable Are the Acceptability Assessment
Category Sub- Level of Impact Impacts of
category an
Acceptable
Level?
Physical N/A N/A N/A N/A
Environment
Biological Threatened No significant Yes Shell implements MARPOL
Environment and impacts to listed standards and internal controls in
Migratory Threatened relation to managing wastes, which
Species (Endangered reduces the likelihood of wastes
and Vulnerable) being accidentally released to the
or Migratory marine environment. Given the
MNES fauna remote location and distance from
populations important habitats of the Operational
Area, any accidental release of
wastes to the environment would not
be expected to interact with a large
number of threatened or migratory
MNES species.
Socio- N/A N/A N/A N/A
economic
and Cultural
Environment

The assessment of risks from waste determined the residual risk rating of Dark Blue
(Table 9-73). As outlined above, the acceptability of the risks from waste associated
with the Prelude project has been considered in the following context.
Principles of ESD
The risks from waste are consistent with the principles of ESD based on the following
points:
• The environmental values/sensitivities within the Operational Area are not expected to
be significantly impacted, and
• The precautionary principle has been applied to the risk assessment.
Relevant Requirements
Management of the risks from waste are consistent with relevant legislative
requirements, including:
• MARPOL Annex V as ratified by the Protection of the Sea (Prevention of Pollution from
Ships) Act 1983
• Navigation Act 2012 (Cth) and Protection of the Sea (Prevention of Pollution) Act 1983
(Cth):
o Marine Order 94 – Marine pollution prevention – packaged harmful substances
o AMSA Marine Order 95 (marine pollution prevention – garbage).
• Radiation Safety Act 1975 (WA)
• Code of Practice for the Safe Transport of Radioactive Material (Australian Radiation
Protection and Nuclear Safety Agency 2019)

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• Management of impacts and risks are consistent with policies, strategies, guidelines,
conservation advice, and recovery plans for threatened species (Table 9-76).

Matters of National Environmental Significance

Threatened and Migratory Species
The evaluation of waste risks indicates significant risks to threatened and migratory
species will not credibly result from the waste aspect of the Prelude petroleum activities
given the limited number of animals that could potentially be impacted in the unlikely
event of an unplanned release.
Alignment of the Prelude petroleum activities with management plans, recovery plans
and conservation advice for threatened and migratory fauna is provided in Table 9-76.
Commonwealth Marine Environment
The impacts and risks from the waste aspect of the Prelude field on the
Commonwealth marine environment will not exceed any of the significant impact
criteria provided in Table 8-1.

Table 9-76: Summary of Alignment of the Risks from the Waste Aspect of the Prelude
Petroleum Activities with Relevant Requirements for EPBC Threatened Fauna

Matters of MNES Acceptability Threats Demonstration of Alignment as Relevant

National Considerations (Significant Relevant to the to the Project
Environmental Impact Criteria, EPBC Project
Significance Management
Plans/Recovery
Plans/Conservation
Advices)
Threatened and Conservation advice on sei Pollution Waste generated during the petroleum
Migratory whale (Balaenoptera (persistent toxic activities described in this EP will be
Species borealis) (DoE 2015c) pollutants) managed in accordance with standard
Conservation advice on fin Pollution maritime requirements, international
whale (Balaenoptera (persistent toxic conventions (MARPOL), relevant Marine
Orders and Shell’s internal management
physalus) (DoE 2015d) pollutants)
system requirements. This management
Conservation management Habitat reduces the likelihood of the accidental
plan for the blue whale: A modification release of hazardous and non-hazardous
recovery plan under the including wastes into the marine environment.
Environment Protection and presence of oil
Biodiversity Conservation Act and gas
The frequency, quantities and nature of
1999 2015–2025 platforms/rigs,
wastes that may be accidentally released into
(Commonwealth of Australia marine debris
the environment are unlikely (C) to result in
2015a) infrastructure and
significant impacts to threatened/migratory
acute/chronic
species or the Commonwealth Marine
chemical
Environment (Table 8-1).
discharge

Conservation advice on Entanglement –

humpback whale (Megaptera marine debris
novaeangliae) (DoE 2015b)
Significant impact guidelines Marine debris
for Critically Endangered,
Endangered, Vulnerable and
Migratory species (Table 8-1)
Recovery Plan for Marine Marine debris
Turtles in Australia 2017–

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Matters of MNES Acceptability Threats Demonstration of Alignment as Relevant

National Considerations (Significant Relevant to the to the Project
Environmental Impact Criteria, EPBC Project
Significance Management
Plans/Recovery
Plans/Conservation
Advices)
2027 (Commonwealth of
Australia 2017)
Conservation advice on Marine debris
leatherback turtle
(Dermochelys coriacea)
(DEWHA 2008)
Significant impact guidelines Marine debris
for Critically Endangered,
Endangered, Vulnerable and
Migratory species (Table 8-1)
Conservation advice on Marine debris
whale shark (Rhincodon
typus) (DoE 2015e)
Significant impact guidelines Marine debris
for Critically Endangered,
Endangered, Vulnerable and
Migratory species (Table 8-1)
Commonwealth Significant Impact Guidelines Marine debris
Marine Area for the Commonwealth
marine environment (Table
8-1)
Threat abatement plan for Marine debris
the impacts of marine debris
on vertebrate marine life
(DEWHA 2009c)
Wetlands of N/A N/A N/A
International
Importance

External Context
There have been no objections or claims raised by Relevant Persons to date around
the waste aspect. Shell’s ongoing consultation program will consider statements and
claims made by stakeholders when undertaking future assessment of risks.
Internal Context
Shell has also considered the internal context, including Shell’s Waste Strategy and
Guidelines, environmental policy and ESHIA requirements. The EPOs, and the controls
which will be implemented, are consistent with the outcomes from stakeholder
consultation for the Prelude FLNG facility and Shell’s internal requirements.
Acceptability Summary
The assessment of and risks from waste determined the residual risk rating to be Dark
Blue (Table 9-6). As outlined above, the acceptability of the impacts and risks from
waste have been considered in the context of:
• The established acceptability criteria for the waste aspect
• ESD

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• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
Shell considers residual risks of Dark Blue or lower to be inherently acceptable if they
meet legislative and Shell requirements. The discussion above demonstrates that
these requirements have been met in relation to the waste aspect.
Based on the points discussed above, Shell considered the risks from waste
associated with the petroleum activities described in this EP to be acceptable.

9.12.6 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

No injury or mortality of listed Threatened or Fauna observations and incident reports
Migratory MNES species as a result of unplanned demonstrate no mortality of listed Threatened or
waste discharge to sea. Migratory species as a result of unplanned waste
discharged from the petroleum activities within the
Operational Area.

9.13 Emergency Events

9.13.1 Scenario Context

Several unplanned events (i.e. incidents or emergencies) resulting in the potential for
large-scale releases of hydrocarbons or chemicals were identified for Prelude FLNG
Operations, including:
• Loss of containment (LOC) of well fluids from subsea infrastructure (e.g. production
wells, manifolds, flowlines or risers)
• LOC during FLNG product storage and offloading (LNG, LPG or condensate)
• LOC of heavy fuel oil to sea from marine vessels or product offtake tankers
• LOC of diesel during refuelling or following a collision between any marine vessels
operating in the field
• accidental discharge of hazardous liquids or hazardous liquid wastes (e.g. MEG, amine,
helifuel, etc) during bulk liquid transfers or lifting operations.
A worst-case scenario resulting from each of these events has been considered in this
environmental risk assessment. Each of these scenarios is discussed further in this
section. Each of these scenarios can result in smaller spills than the worst-case
credible spills discussed below. The smaller spills have not been discussed specifically
as their consequences will be lesser in both magnitude and impact.
LOC from Subsea Infrastructure
Prelude subsea infrastructure includes seven production wells, two production
manifolds and one drill centre, four production flowlines, a riser manifold and risers as
well as the well control umbilical. LOC could occur from any of these facilities due to
e.g. a dropped object, corrosion, erosion, human error and/ or reservoir or external

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environmental events that could exceed the design tolerance of any of the components
of this system.
Of these events, loss of well control incidents are known to be associated with the
largest potential for environmental harm due to the large volumes of hydrocarbons
contained in the reservoir and the considerable amount of time it requires to drill an
offset relief well and stop the flow of reservoir fluids to the environment. Loss of well
control incidents are most likely to occur during well drilling or workover when there is
an open path for well fluids from the reservoir to surface, and reliance is on control
systems and operators to detect an abnormal situation in its incipient stages to prevent
it from escalation.
Drilling or workovers are not considered in scope of this EP, and any future
requirements will be addressed in standalone campaign specific EPs and associated
documentation. Now in the production phase, the source control responses will be
different from drilling and completion operations. During the drilling phase, prior to
Xmas tree installation, a capping stack can form a major component of a source control
response plan, this is no longer the case. The current configuration of the Prelude
production wells, with subsea Xmas trees installed and connected to subsea flowlines,
negate the use of a capping strategy. Only for well activities where the Xmas tree is
removed is this a viable consideration. As described in Section 6.4.4, there are no
planned drilling or well workover activities during the life of this EP. Furthermore, in the
event of the complete removal due to major damage of the production tree, debris
clearance and capping activities are not considered viable as there would not be any
infrastructure to land the cap on and secure it for well control operations.
Production well LOC events, although rare, are still a possibility and range from minor
breaches in containment (pinhole leaks from corroded/ eroded piping or valves)
through to large release events.
Drilling of a relief well would be the primary method of source control due to the
presence of the subsea Xmas tree that would preventing access for the installation of a
capping stack.
The modelled well fluids flow rate and therefore the worst credible discharge, in the
second scenario is estimated at 20,000 bbl (3,180 m3) per day, yielding a total released
volume of 1,600,000 bbl (254,400 m3). This rate is based on the maximum rate of gas
flow expected from the most productive of the seven Prelude wells during production
drilling, and without the completion in the well, and the number of days (80 days) to drill
a relief well in the case of loss of well control. This volume has been used for oil spill
predictive modelling (Section 9.13.2) and the risk assessment presented in this section
of the EP. This volume has also been used as the basis for oil spill planning described
in the OPEP.
The worst case discharge, defined as the maximum rate a well will flow, depends on
the design configuration. The modelled well fluids flow rate is considered to be highly
conservative because it is based on using the flow rates from the Upper Limit rather
than the Base Case or High Case for a blowout through 9 5/8" casing, and does not
allow for the additional frictional pressure drop from having a completion in the well.
The actual worst credible discharge during operations (blowout through the 7"
production tubing) is predicted to be 10,138 bbl (~1,611 m³) per day, yielding a total
release volume of 811,040 bbl (128,944 m³) over 80 days.
The likelihood of such incidents in Australia has been very low. A report on world-wide
well control incidents commissioned by the US Department of the Interior (Bercha

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International Inc. 2014) indicates the frequency of production well control incidents in
Australia, derived from Gulf of Mexico incident data (1980 – 2014), to be 0.104
incidents per 1000 well years, or 1.04E-04 per well year. For the 7 production wells in
the Prelude field, this translates into a frequency of 7.3E-04 well control events per
annum, or remote likelihood of a well incident. Note that the higher the well fluids loss
flowrate, the lower the frequency of well blowout in accordance with the formula
derived by DNV based on historical data i.e. 6.9 x 10-5 Q-0.3 per well year, where Q is
the mass of spilled hydrocarbons in tonnes (Det Norske Veritas, 2011).
All other releases from subsea infrastructure will be orders of magnitude smaller in
volumes lost to sea compared to the uncontrolled production well release scenario with
SCSSV failure. These smaller release scenarios have not been discussed or modelled
further.
LOC from Product Storage and Offloading
The liquid product streams on Prelude are LNG, LPG (propane and butane) and
condensate. During production these are rundown to their respective cargo storage
tanks within the substructure and stored at atmospheric pressure. The substructure is
double hulled on each side extending over the full length of the storage tanks. LNG,
LPG and condensate storage tanks are located inboard of segregated ballast tanks
covering the full length of the storage area and are separated from each other by either
a void space or a ballast tank. In addition, the tanks are protected from the topsides
hazards by a main deck designed to withstand explosion overpressure, jet fire and
cryogenic spills. A heating system is installed to heat the transverse cofferdams and
the upper portion of the centreline water ballast tanks surrounding the cargo tanks to
maintain the temperature of the structure and prevent brittle failure.
LNG or LPG leaks from the topsides process modules or any hydrocarbon release from
the cryogenic areas of the plant are directed to sea to protect the facility from damage
due to cryogenic spills and prevent process safety incidents and escalation. Topsides
condensate spills on the FLNG, however, are designed to be captured and contained in
the drainage system (Appendix 13.0) and reclaimed back into the process where
possible or disposed of appropriately.
Only a single product stream is offloaded at any one time.
LOC from LNG and LPG Storage and Loading
The FLNG Ship Collision Study and Collision Analysis for Substructure indicate a
remote to extremely remote likelihood of ship collision as detailed in the Prelude FLNG
Safety Case (Shell Australia 2017). The overall collision frequencies are dominated by
the contribution of the low energy on approach supply and product offtake vessels,
which would cause no breach of the outer hull but localised damage only.
For a loss of containment of LNG, LPG or condensate product from a single cargo tank
to occur, collision energy levels between 193 and 500 MJ should be imparted to the
FLNG hull. Energy levels greater than 500 MJ could cause extensive hull damage with
release of large volumes of products. These high-energy impacts could only be
associated with large passing vessels travelling at cruise speed.
Based on known shipping routes and annual traffic through the Prelude area, the
annual frequency of collisions resulting in single storage tank failure and loss of
containment is estimated at 4.7E-05/year and the catastrophic FLNG vessel failure
frequency is 3.8E-05/year (Shell Australia 2017).

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Smaller volume LNG and LPG spills could occur during LNG or LPG loading. LNG
loading occurs each week at the dedicated Prelude LNG loading platform, typically
over the course of 24 hrs, at a maximum combined loading rate of 10,000 m3/h. LPG
loading occurs once a month at a rate of 3000 m3/h.
An LNG or LPG spill could result from e.g. inadvertent move of the FLNG or LNG/ LPG
tanker beyond the design tolerance of the loading arms, causing arm disconnection,
parting or failure; material failure due to corrosion, erosion; temperature embrittlement;
overpressure or dynamic loading from product fluids, adverse weather, etc.
At the end of an LNG/ LPG carrier loading the loading arms are emptied forward to the
carrier. Then the LNG/ LPG offloading header and offloading arm manifolds are
drained to the LNG/ LPG storage tanks assisted by nitrogen purge. In the event of an
emergency during loading, the loading header is emptied to the tanks by gravity.
LNG and LPG are gases at ambient temperatures, hence any LOC from the cargo
tanks or during loading will ultimately result in loss to atmosphere and therefore cause
no damage to the marine environment. The main concern with such events is the
potential for fires or explosions presenting risks to personnel and property and these
are addressed in the Prelude FLNG Safety Case. Environmental risks related to such
releases are therefore considered non-credible and have not been discussed further.
LOC from Condensate Storage and Loading
Six atmospheric pressure condensate storage tanks are located in the aft section of the
FLNG hull. Each tank has a capacity of 21,054 m3 at 95% full and is supplied with two
offloading pumps. During offloading mode all twelve offloading pumps are expected to
be in operation, delivering condensate at a rate of 5,000m3/hr to the condensate
tanker. This allows offloading of up to 120,000 m3 of condensate (net total pumpable
condensate tanks storage capacity) in 24 hours. Condensate loading occurs
approximately once every two weeks.
A stern tandem offloading arrangement for the discharge of condensate is provided at
the aft end of Prelude. Condensate tankers are designed to be moored in the
conventional manner for Single Point Mooring (SPM) bow mooring terminals with a
standard OCIMF single braided (DN 400/DN 500) floating hose string deployed to the
standard mid-ship manifold. Berthing utilises a hawser and hold-back support vessel
rather than dynamic positioning. The condensate floating hose is stowed on an aft hose
reel for controlled deployment and recovery. After offloading the remaining condensate
in the hose is transferred back to the condensate tank by N2 purge. A washing system
is provided to allow washing of the hose back to the slops tanks to minimise build-up of
waxy deposits within the hose.
Condensate is a liquid at ambient temperature and pressure. It is comprised of low
molecular weight hydrocarbons and has similar characteristics as light diesel fuel. It is
typically volatile and evaporates readily. However, Prelude condensate has a
significant waxy component which may persist after the volatile portion evaporates.
Condensate containment losses from FLNG operations have been estimated as
follows:
• Up to 10 m3 from inadvertent disconnection of a coupling or flange at the topsides
process modules and failure to contain by spill trays and the drain system;
• Up to 1000 m3 for condensate offloading operation by floating hose. At a loading rate of
5,000 m3 per hour, these quantities reflect a major loss of containment from rupture of
loading hose and failure to respond within 15 minutes; or

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• Release of cargo due to a high impact vessel collision and breach of hull and storage
tank containment. A 42,000 m3 release of condensate released over a period of 2 hours
has been considered.
The last scenario is considered as the worst-case credible scenario and has been
modelled for impact assessment purposes.
LOC of Heavy Fuel Oil / Intermediate Fuel Oil
The product offtake tankers could potentially carry heavy fuel oil (HFO)/ Intermediate
Fuel Oil (IFO) as fuel. Any HFO/ IFO spill will result from a tanker collision with other
vessels such as other tankers or an attendant vessel during berthing or unberthing
operations as a result of e.g. human error, adverse sea/ weather conditions, loss of
navigation aid systems, mechanical breakdown, miscommunication or tug failure.
Given the average volume of HFO/IFO stored in LNG carriers (up to 5,000 m3) and the
low energy collision credible during berthing/ unberthing, a 1,000 m3 HFO spill was
modelled. This is considered highly conservative given impact energy is highly unlikely
to result in a HFO/ IFO tank breach.
LOC of Diesel
A diesel spill to the Operational Area could occur as outcome from:
• LOC during diesel transfer from the supply vessel to the FLNG facility; or during
refuelling of the pilot tugs; or
• following a collision between any marine vessels, including the FLNG facility, operating
in the field.
Diesel will be loaded onto the FLNG facility from support vessels approximately once
per month. This refuelling operation takes at least 4 hours per to complete. A spill could
occur as a result of any of engineering controls failure (e.g. hose rupture, coupling
failures, tank overflow) or human error. However, historically the volume lost to sea in
similar incidents is typically less than 160 litres or 1 bbl. (Det Norske Veritas, 2011) and
potential further losses are reduced by visual observations, shutdown of pumps and
automatic closure of safety valves.
The risk of a spill from vessel to vessel collision depends on the severity of impact, i.e.
the speed and orientation of the vessels during the event. The worst-case scenario is
where one of the vessels is ‘hit’ from the broadside by another vessel moving at near
full speed resulting in a puncture of the diesel tanks below the waterline.
Prelude marine support vessels have diesel storage capacities of around 1,000 m3,
spread in multiple tanks. Pilot tugs carry similar or smaller diesel inventories onboard.
The likelihood of collision between supply and support vessels and any other vessels in
the field is considered remote given the low frequency of vessel collisions in ports
resulting in fuel loss of containment (Det Norske Veritas, 2011) further reduced by the
fact that the Operational Area is far less busy than any other Australian or international
port.
The largest diesel volume spill scenario is considered to be from a supply vessel
collision with the FLNG facility of magnitude such that a breach of the hull and damage
to its biggest diesel storage tank would occur. The tank is located in the FLNG facility
substructure and has a capacity of 750 m3. It has been conservatively assumed for the
purposes of spill modelling that in the remote chance of this happening, the whole
inventory of this tank would be lost to sea. The likelihood of this event happening is

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estimated as remote given no such events have occurred in Shell or are known of in
the industry.
LOC of Hazardous Liquids
Accidental loss to sea of hazardous liquids other than hydrocarbons (e.g. amine, MEG,
hydraulic/ lube oil etc.) could occur at the Prelude location due to any of the following
events:
• accidental opening of an isolation valve during normal operations
• hose failure or failure to isolate inventory during bulk liquid transfers
• lifting operations between marine vessels, including the FLNG
• adverse weather conditions resulting in dislodgement/ failure of storage vessel(s).
The worst-case spill scenarios for amine and MEG are summarised as follows:
• a 1-hour release of 1,000 m3 of amine (methyl-diethanolamine (MDEA) containing 10-
30% Piperazine) at sea surface following a complete rupture of the FLNG amine storage
tank.
• a 1-hr 6,000 m3 release of MEG (80% pure MEG and 20% seawater) at sea surface
following a complete rupture of the FLNG MEG storage tank.
The likelihood of such events are expected to be low.

9.13.2 Overview of Unplanned Spill Modelling

Numerical modelling studies were commissioned for the worst-case credible spill
scenarios outlined above.

Table 9-77 Summary of Modelled Hydrocarbon and Hazardous Liquids Scenarios

Volume (m3)
Hazardous
Longitude

Depth (m)
Scenario

Location

Duration
Latitude

Liquid
Name

Total

Loss of well Prelude 13°50‟22” 123°19‟35.8” 237 Well fluid 80 days 254,400
control Production S E
Well

Loss of Prelude 13°47.2´S 123°19.0´ E. surface Condensate 2 hours 42,000

containment FLNG
during
product
offloading
(collision)

Loss of Prelude 13°47.2´S 123°19.0´ E. surface HFO 1 hour 1,000

containment FLNG
of heavy
fuel oil

Loss of Prelude 13°47.2´S 123°19.0´ E. surface Diesel 1 hour 750

containment FLNG
of diesel

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Loss of Prelude 13°47.2´S 123°19.0´ E. surface Amine 1 hour 1,000

containment FLNG
of amine

Loss of Prelude 13°47.2´S 123°19.0´ E. surface MEG 1 hour 6,000

containment FLNG
of MEG

The following models were used to predict impacts from these scenarios:
• Loss of well control was modelled using the Integrated Oil Spill Impact Model System
(SIMAP) model with each simulation run for 108 days.
• Condensate and HFO spills were modelled using SIMAP, whereby 100 replicates over
4 seasons were run for 56 days each.
• The diesel spill scenario was modelled using the OILMAP-Deep model for nearfield
modelling and the SIMAP model for the far field effects. 200 replicates over four
seasons were run.
• Amine and MEG spill modelling were carried out using the three-dimensional chemical
spill trajectory and weathering model, CHEMMAP (Chemical Mapping and Analysis
Program). Amine and MEG modelling used 100 replicates per two seasons (summer
and winter). In the case of amine, each simulation was run for 5 days, whilst for MEG, it
was run for 4 days.
SIMAP and CHEMMAP represent 3D stochastic models, with physical fates component
for oils and chemicals, biological effects and exposure component, GIS component,
and environmental features, oil/ chemical and biological databases. OILMAP-Deep is a
2D/3D deterministic model, simulating the fate of oil in the environment (surface, water
column and air distribution), interactions with the ecological component of the
environment and has a stochastic component which determines the probability and
time contours of oiling of the various environmental components and the most likely
spill paths on a monthly, seasonal, or annual basis. The metocean conditions used as
input to each model were derived from a 39-year data set of current speed and
direction at half-hourly intervals.
A stochastic modelling scheme was followed for each modelled scenario, whereby the
respective model was applied to repeatedly simulate the defined spill scenario using
different samples of current and wind data. Starting dates for each simulation were
distributed between the seasons (e.g. summer and winter) to capture the influence of
the temporal and spatial variations in the current patterns that would affect the
trajectory of any hydrocarbon or chemical spills that commenced in these periods. The
results of the replicate simulations were then statistically analysed and mapped to
define contours of risk around the release point.
For hydrocarbons, the timeseries contour compilations include floating, entrained,
dissolved and accumulated hydrocarbons.
Hydrocarbon Impact Thresholds
Spilled hydrocarbons can exist as floating, entrained, dissolved and accumulated (i.e.
stranded onshore) hydrocarbons. Each of these fractions/ phases can interact with the
environment in diverse ways due to different pathways to receptors and cause/effect
mechanisms. Guideline impact thresholds (NOPSEMA 2019b) for floating, entrained,
dissolved and accumulated hydrocarbons were applied to the hydrocarbon spill
modelling studies and used to inform the assessment of potential impacts and risks.
Three thresholds were applied to each phase i.e. low exposure, moderate exposure
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and high exposure. These are described in Table 9-78 and are used to delineate the
extent (outer edge) of the low, moderate or high exposure zones for each hydrocarbon
type. The low, moderate and high exposure zones represent bands/ ranges of
hydrocarbon concentrations, grouped on the basis of scientific knowledge of potential
impacts of the various hydrocarbon phases on environmental receptors.

Table 9-78: Hydrocarbon Exposure Zones and Thresholds

Exposure Zone Threshold Justification

Floating Oil

Exposure Zone 1 g/m2 The 1 g/m2 threshold represents the practical limit of observing
Low (1 g/m2 – 10 hydrocarbon sheens in the marine environment and therefore
g/m2) has been used to define the outer boundary of the low exposure
zone. This threshold is considered below levels which would
cause environmental harm and is more indicative of the areas
perceived to be affected due to its visibility on the sea-surface.
This exposure zone represents the area contacted by the spill
and defines the conservative outer boundary of the ZPI from a
hydrocarbon spill.

Adverse exposure 10 g/m2 Ecological impact has been estimated to occur at 10 g/m2 as this
zone level of oiling has been observed to mortally impact birds and
Moderate other wildlife associated with the water surface (French et al.
(10 g/m2 – 25 g/m2) 1996; French 2000). Contact within this exposure zone may
result in impacts to the marine environment.

Adverse exposure 25 g/m2 The 25 g/m2 threshold is above the minimum threshold observed
zone to cause ecological impact. Studies have indicated that a
High (> 25 g/m2) concentration of surface oil 25 g/m2 or greater would be harmful
for the majority of birds that contact the hydrocarbon at this
concentration (Koops et al. 2004; Scholten et al. 1996).
Exposure above this threshold is used to define the high
exposure zone.

Accumulated (Shoreline) Oil

Exposure zone 10 g/m2 A threshold of 10 g/m2 has been defined as the zone of potential
Low ‘low’ exposure. This exposure zone represents the area visibly
(10 g/m2 – 100 contacted by the spill and defines the outer boundary of the ZPI
g/m2) from a hydrocarbon spill.

Adverse exposure 100 g/m2 French et al. (1996) and French-McCay (2009) have defined an
zone oil exposure threshold of 100 g/m2 for shorebirds and wildlife
Moderate (furbearing aquatic mammals and marine reptiles) on or along
(100 g/m2 – 1,000 the shore, which is based on studies for sub-lethal and lethal
g/m2) impacts. The 100 g/m2 threshold has been used in previous
environmental risk assessment studies (French et al. 2011;
Adverse exposure 1,000 g/m2 French-McCay 2004; French-McCay 2003; French McCay et al.
zone 2012; National Oceanic and Atmospheric Administration 2013).
High (> 1,000 g/m2) This threshold is also recommended in AMSA’s foreshore
assessment guide as the acceptable minimum thickness that
does not inhibit the potential for recovery and below which is
best remediated by natural coastal processes alone (AMSA
2015). Thresholds of 100 g/m2 and 1,000 g/m2 will define the
zones of potential ‘moderate’ and ‘high’ exposure on shorelines,
respectively. Contact within these exposure zones may result in
impacts to the marine environment and coastal areas.

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Exposure Zone Threshold Justification

Entrained Hydrocarbons

Exposure zone 10 ppb The 10 ppb threshold represents the lowest concentration and
Low exposure (10 corresponds generally with the lowest trigger levels for chronic
parts per billion exposure for entrained hydrocarbons in the ANZECC &
(ppb)–100 ppb) ARMCANZ (2000) water quality guidelines. Due to the
requirement for relatively long exposure times (> 24 hours) for
these concentrations to have an observable impact, they are
likely to be more meaningful for juvenile fish, larvae and
planktonic organisms that might be entrained (or otherwise
moving) within the entrained oil plumes, or when entrained
hydrocarbons adhere to organisms or entrained oil is trapped
against a shoreline for periods of several days or more. This
exposure zone is not considered to be of significant biological
impact. This exposure zone represents the area contacted by
the spill and conservatively defines the outer boundary of the
ZPI from a hydrocarbon spill.

Adverse exposure 100 ppb The 100 ppb threshold is considered conservative in terms of
zone potential for toxic effects leading to mortality for sensitive mature
Moderate (100 ppb– individuals and early life stages of species. This threshold has
500 ppb) been defined to indicate a potential zone of acute exposure,
which is more meaningful over shorter exposure durations.
The 100 ppb threshold has been selected to define the moderate
exposure zone. Contact within this exposure zone may result in
impacts to the marine environment.

Adverse exposure 500 ppb The 500 ppb threshold is considered a conservative high
zone exposure level in terms of potential for toxic effects leading to
High (> 500 ppb) mortality for more tolerant species or habitats. This threshold
has been defined to indicate a potential zone of acute exposure,
which is more meaningful over shorter exposure durations. The
500 ppb threshold has been selected to define the high
exposure zone.

Dissolved Aromatic Hydrocarbons

Exposure zone 6 ppb The threshold value for species toxicity in the water column is
Low (6 ppb–50 ppb) based on global data from French et al. (1999) and French-
McCay (2003, 2002), which show that species sensitivity (fish
and invertebrates) to dissolved aromatics exposure > 4 days
(96-hour LC50) under different environmental conditions varied
from 6 ppb–400 ppb, with an average of 50 ppb. This range
covered 95% of aquatic organisms tested, which included
species during sensitive life stages (eggs and larvae). Based on
scientific literature, a minimum threshold of 6 ppb is used to
define the low exposure zones (Clark 1984; Engelhardt 1983;
Geraci and St Aubin 1988; Jenssen 1994; Tsvetnenko 1998).
This exposure zone is not considered to be of significant
biological impact and conservatively defines the outer boundary
of the ZPI from a hydrocarbon spill.

Adverse exposure 50 ppb A conservative threshold of 50 ppb was chosen as it is more

zone likely to be indicative of potentially harmful exposure to fixed
Moderate (50 ppb– habitats over short exposure durations (French-McCay 2002).
400 ppb) French-McCay (2002) indicates that an average 96-hour LC50 of
50 ppb could serve as an acute lethal threshold to 5% of biota.
The 50 ppb threshold has been selected to define the moderate

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Exposure Zone Threshold Justification

exposure zone. Contact within this exposure zone may result in
impacts to the marine environment.

Adverse exposure 400 ppb A conservative threshold of 400 ppb was chosen as it is more
zone likely to be indicative of potentially harmful exposure to fixed
High (> 400 ppb) habitats over short exposure durations (French-McCay 2002).
French-McCay (2002) indicates that an average 96-hour LC50 of
400 ppb could serve as an acute lethal threshold to 50% of
biota. The 400 ppb threshold has been selected to define the
high exposure zone.

The dissolved aromatic hydrocarbon impact thresholds presented in Table 9-78 are
considered conservative and appropriate for the assessment of impacts on marine
receptors given evidence on impacts from additional ecotoxicity studies. For example,
the Browse Joint Venture (JV) ecotoxicity testing of Calliance condensate (ESA, cited
in Woodside Energy Limited, 2013) on a broad range of taxa of ecological relevance
indicated no observed effect concentrations were achieved at concentrations orders of
magnitude greater than the 400 ppb threshold for the High Exposure Zone. Calliance
condensate is considered to be broadly similar to Prelude condensate given a similar
location, geology, formation, and depth.
Calliance ecotox testing (Woodside Energy Limited, 2013) showed results for no
observed effect concentrations per Table 9-79.
Table 9-79: Browse JV Ecotox testing on Calliance Condensate

*Source: Table 5-5 from Woodside’s Outer Canning Exploration Drilling Program Environment Plan (Woodside 2013).

The dissolved and entrained thresholds are instantaneous measures and based on the
results of testing presented in table above are highly conservative. These thresholds
are also considered appropriate for diesel and HFO/ IFO given the similarity in cause
effect pathways.
Chemical (Amine and MEG) Impact Thresholds

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Environmental threshold values for amine were developed from literature, following the
ANZECC Guidelines (2000; 2018). An ecotoxicity value was derived for amine’s main
component, MDEA, by identifying previous studies with ecotoxicity results for marine
organisms and using the ANZECC Guidelines to derive a threshold. Five ecotoxicity
thresholds were identified from different sources, which were used to determine a
moderate reliability threshold of 1.8 mg/L, which is the lowest LC50 value in Table 9-80
divided by 100.

Table 9-80: The acute or chronic toxicity of different aquatic organisms and the time
period of exposure
Source Type of Acute
Exposure Time Toxicity Value
Organism (species) or Chronic
Period (hour) (mg/L)
Toxicity
Fish MSDS LC50 Not specified in
1,466
(unknown) study
Algae Hansen et al
EC50 48
(skeletonema 141.4
costatum)
Zooplankton Hansen et al LC50 Not specified in
183.4
(Calanus finmarchicus) study
Algae/bacteria Brooks, 2008 EC10
0.25 36
(Vibrio fischeri)
Carp Brooks, 2008 LOEC Not specified in
0.5
(Cyprinidae) study

For MEG, which is classified as "practically non-toxic" to aquatic organisms by the U.S.
Environmental Protection Agency (USEPA) and PLONOR under the OSPAR
Commission, the Predicted No Effect Concentration (PNEC) of 859 mg/L,
recommended by the World Health Organisation (WHO 2000), was used in assessing
modelling outcomes. The MEG PNEC was derived from the No Observed Effect
Concentration (NOEC) of 8590 mg/L for chronic exposure of daphnids (reproductive
end point assessment) divided by a safety factor of 10 (WHO 2000). This concentration
is two orders of magnitude lower than MEG’s LC50 values for other aquatic organisms
(e.g. aquatic invertebrates, fish and tadpoles, in WHO 2000) and is therefore
considered appropriate. The chemical is also considered as non-persistent in the
environment and does not bioaccumulate (Staples et al. 2001).

9.13.3 Summary of Loss of Containment Modelling Results

Loss of Well Control
A loss of containment due to loss of well control will involve the turbulent discharge of
gas and condensate at the seabed through a restriction (the well head). The
condensate will be discharged as a jet of small droplets into the water column (237 m
below sea level) which would be carried forth and upwards to the sea surface by the
buoyancy of the gas cloud, which will be counteracted by the viscous resistance
imparted by the surrounding seawater. Where the release occurs at water depths
exceeding 100-200 m, the gas plume would lose its momentum prior to breaking
through to the surface and the entrained oil droplets may become trapped by the
density layers in the water column (Chen & Yapa, 2002).
Thus, for deeper releases (>200 m), the gas and oil will tend to separate before the oil
surfaces because the gas either goes into solution or accelerates away from the oil
droplets. The height at which the gas lift ceases is referred to as the trapping height.
The rate at which oil rises from the trapping height will be determined by a number of
factors, including the relative buoyancy of the oil versus local water density, the size of
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the droplets (increased viscous resistance for smaller sizes), the presence of density
barriers in the water column and the action of shear currents that might be present in
that location.
The Prelude OILMAP-Deep model included specification of the discharge rate, hole
size, gas-to-oil ratio, the temperature of the oil on exiting and before subsequent
cooling by the ambient water. The temperature and salinity profiles of the water column
were also specified to describe the vertical density profile.
The plume trapping height (where the gas lift ceases) was estimated at approximately
213 m above seabed, hence approximately 24 m below sea level. The diameter of the
water and condensate plume at this level was estimated at approximately 27.1 m.
Based on the small oil droplet sizes forecast by OILMAP-Deep (15.1-90.0 µm), the
droplets will then rise slowly at a net rate determined by their buoyancy relative to the
surrounding water density and the viscous resistance imposed by the water. The
results essentially suggest that the majority of the oil will be entrained into the upper
mixed layer of the ocean, with some surfacing potential based on the proportion of
larger droplets.
Key results from the SIMAP stochastic modelling studies for a worst-case loss of well
control LOC showed:
• Floating hydrocarbons will predominantly surface in the immediate vicinity of the
release site with concentrations above the low exposure threshold most frequently
occurring in waters to the northwest and southeast, with the furthest travelled distance
from the release site being to the north-northeast and the west-southwest.
Concentrations of floating oil ≥1 g/m2 could potentially be found up to 875 km to the
west-northwest of the release site. The 10 g/m2 threshold is contained within 10 km
from the release site, whilst the high exposure threshold is never exceeded. The
annualised probability of floating oil at concentrations of 1 g/m² or greater reaching
nearshore waters is predicted to be 6% at Browse Island, 5% at Heywood Shoals, 4% at
Echuca Shoals and ≤3% for all other assessed sensitive receptors. Probability of
contact <0.5% is predicted for nearshore waters to all sensitive receptors by floating oil
concentrations of 10 g/m² or greater.
• The highest maximum local accumulated shoreline concentration from the single
worst case modelling run is predicted at the Indonesian Boundary receptor at 3 kg/m²,
and the highest maximum local accumulated shoreline volume is also predicted for this
receptor at 51 m³, ~0.02% of spilled volume. The probability of contact of floating oil film
with this receptor from all replica runs is predicted to be less than 0.5%.
• For Australian receptors, the highest maximum local accumulated shoreline
concentration from the single worst case modelling run is predicted at the Buccaneer
Archipelago at 123 g/m², and the highest maximum local accumulated shoreline volume
is also predicted for this receptor at 1.1 m3. The probability of contact of floating oil film
with this receptor from all replica runs is predicted to be less than 0.5%. For all
receptors, the highest maximum local accumulated shoreline concentration is predicted
at the Indonesian Boundary receptor at 3,034 g/m², and the highest maximum local
accumulated shoreline volume is also predicted for this receptor at 51 m3 (less than
0.5% probability).
• Entrained hydrocarbon concentrations above 10 ppb were predicted to potentially
reach waters 2,200 km to the west of the release site and to waters south of Shark Bay
(1,800 km southwest) The forecast maximum potential extent for entrained
concentrations above the 100 ppb moderate exposure threshold is also around 2,200
km to the west of the release site and as far southwest as waters off Bernier and Dorre
Islands (~1,500 km southwest). At the highest threshold of 500 ppb, the forecast
maximum potential extent is also up to around 2,000 km west of the release site and as

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far southwest as North West Cape (1,200 km southwest). The highest annualised
probabilities for entrained concentrations ≥10 ppb contacting the nearshore waters of
receptors are predicted for Heywood Shoals (96%), Browse Island (94%) and Echuca
Shoals (94%). Probabilities for contact of >80% are also indicated for the nearshore
waters of Ashmore Reef (89%), Cartier Island (87%), Barracouta Shoals (87%), Vulcan
Shoals (86%), Seringapatam Reef (84%), Hibernia Reef (84%) and Fantome Shoals
(83%). Highest probabilities for contact at 100 ppb or greater are predicted for Browse
Island (90%) and for contact above 500 ppb, a highest probability of 83% is indicated,
also for Browse Island.
• Dissolved aromatic hydrocarbons follow similar directions to those outlined for the
entrained condensate. The annualised outer contours of probability indicate the potential
for concentrations at or above 6 ppb to occur in waters up to 2,000 km to the west-
northwest of the release site. The forecast maximum potential extent for dissolved
aromatic hydrocarbons ≥50 ppb could also stretch in isolated patches up to 2,000 km
west of the site. At a threshold of 400 ppb, the predicted maximum extent reduces to
around 1,500 km west-northwest of the release site in isolated transient patches. The
highest annualised probability for concentrations of at least 6 ppb in the nearshore
waters of receptors is forecast for Ashmore Reef at 94%. Risks for contact of 90% or
above are also indicated for nearshore waters of Echuca Shoals (92%), Heywood
Shoals (92%), Cartier Island (92%), Browse Island (90%) and Barracouta Shoals (90%).
For contact by plumes with concentrations of at least 50 ppb and 400 ppb, the highest
probabilities are predicted at 79% and 30%, respectively, for the nearshore waters of
Browse Island. The maximum dissolved aromatic hydrocarbon concentration, at any
depth, is also forecast for the Browse Island receptor at 7,815 ppb (~7.8 ppm).

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Figure 9-28: Extent of the ZPI (low exposure threshold) and the moderate exposure
thresholds (floating, dissolved and entrained) based on the stochastic results of all worst
case credible spill scenarios combined

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Condensate Spill
Key results from the SIMAP stochastic modelling study (APASA 2014) for the worst-
case condensate LOC event during offloading operations showed:
• Floating oil at or above 1 g/m2 is forecast to extend up to 820 km to the west of the
release site and up to 650 km to the north or southwest of the release site. The 10 g/m2
contour is forecast to extend up to 460 km west / southwest and north / northwest and
distances of up to 330 km west / southwest and 370 km north of the release site for the
25 g/m2 contour. The probability of contact for low, moderate and high exposure
thresholds for the nearest sensitive receptors at Browse Island is 6.25%, 2.75% and
1.75% respectively.
• The maximum accumulated shoreline concentration from the single worst case run
is forecast at the Indonesian Boundary at 3.1 kg/m2 with the maximum accumulated
shoreline volume being 1,393 m3 at this receptor. The probability of floating oil contact
with the Indonesian Boundary (cumulative from all runs) is predicted at 0.5%.
• The maximum accumulated shoreline concentration from the single worst case run
for the Australian shoreline is predicted at the Buccaneer Archipelago at 0.7 kg/m2 along
with a maximum accumulated shoreline volume of 14m3. The probability of floating oil
contact with this sensitive receptor (cumulative from all runs) is predicted to be less than
0.25%.
• Entrained oil at or above 10 ppb is forecast to extend up to 1,850 km to the northwest,
850 km to the northeast and 1,150 km to the southwest of the release site. At the 100
ppb threshold, the potential extent is comparable to the lower threshold but the
probabilities of occurrence decrease. Entrained oil at or above 500 ppb is generally
forecast to extend up to 900 km from the release site, with the potential of extending up
to 1,700 km to the west-northwest.
• Dissolved aromatic hydrocarbon concentrations at or above 6 ppb are forecast to
extend up to 1,300 km to the west-northwest and 800 km to the southwest of the release
site. At the 50 ppb threshold, dissolved aromatic hydrocarbons are forecast to extend up
to 700 km, with the potential occurrence of isolated patches at further distances.
Concentrations at or above 400 ppb are generally forecast to extend up to 300 km from
the release site, with the potential of extending up to 600 km to the southwest.
Heavy Fuel Oil Spill
The CHEMMAP stochastic modelling study (APASA, 2014b) for the 1 hr surface 1,000
m3 HFO/ IFO spill event due to ship collision at the Prelude location, modelled over the
summer and winter seasons resulted in the following findings:
• The potential floating oil exposure zones were shown up to 1700 km west / northwest,
500 km east/northeast and 300 km east/northeast of the release location at the low,
moderate and high thresholds respectively.
• The maximum accumulated shoreline concentration within Australian territory is
forecast at the Archipelago (Buccaneer) at 13.3 kg/m2. The maximum accumulated
shoreline volume is also forecast at this receptor at 475 m3. At the Indonesian Boundary,
the maximum accumulated shoreline concentration (averaged over all replicate runs) is
forecast at 23 g/m2, with maximum accumulated shoreline volume (worst case replicate
simulation) at 575 m3(<0.25% probability).
• Entrained oil at or above 10 ppb is forecast to extend up to 20 km from the release site
with probabilities of threshold exceedance less than 5% at this distance. At the 100 ppb
threshold, the potential extent is reduced to within 5 km of the release site. Entrained oil
is not forecast at or above 500 ppb within the model domain.

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• Plumes of dissolved aromatic hydrocarbons with concentrations of 6 ppb or greater

were not forecast to occur within the model domain or within any of the assessed
sensitive receptors.
Diesel Spill
The worst-case diesel spill modelling scenario included 1 hr surface 750m3 release of
Marine Diesel Oil (MDO), nearfield modelling with OILMAP-Deep and SIMAP model
which included 200 replicates per four seasons (APASA, 2014c). The key modelling
results include:
• The potential floating oil exposure zones were shown up to 500 km in the south-
southwest direction and 60 km and 10 km from the release location at the low, moderate
and high thresholds respectively. The probability of floating oil film contact with Browse
Island is 2%, Echuca Shoals 2.5%, Heywood Shoal 1% and less than 0.5% at all other
sensitive receptor locations.
• The maximum accumulated volume in the worst case replicate simulation is 61.1 m3,
6.7 m3, 9.1 m3 and 0.07 m3 at Browse Island, Ashmore Reef, Cartier Island and
Buccaneer Archipelago respectively. The maximum local accumulation averaged among
replicate spills is 25 g/m2 at Browse Island, 7.2g/m2 at Cartier Island and 5.5 g/m2 at
Scott Reef, with less than 1 g/m2 at all other emergent features.
• The 100 ppb entrained oil annualised probability at the closest sensitive receptors is
3% for Browse Island, 4% for Heywood Shoal and 2% for Echuca Shoals with 1% or
less for all other receptors. The probability of contact with entrained oil at the high
exposure level of 500 ppb is less than 0.5% at all sensitivities.
• The annualised probability of exposure to dissolved aromatic hydrocarbons at the
low exposure threshold of 6 ppb is 2% at Browse Island and 1% at Heywood and
Echuca shoals. For all other sensitive locations, this exposure probability is less than
0.5%. Annualised probabilities for the moderate and high exposure thresholds of 50 ppb
and 400 ppb are less than 0.5% at all sensitivities.
MEG Spill
The CHEMMAP stochastic modelling study (APASA, 2019a) for the 1 hour 6,000 m3
MEG spill event during chemical loading operations shows dissolved MEG at or above
859 mg/L (PNEC) is forecast to potentially occur at distances up to 8 km to the east
and 7 km to the west of the release site over both seasons. Easterly trajectories are
forecast to be more dominant in summer months, with concentrations at or above
threshold predicted up to 7 km from the release site to the west. During winter months,
westerly trajectories are forecast to be more dominant, with concentrations at or above
threshold predicted up to 6 km from the release site to the northeast. Dissolved MEG is
not forecast to contact any of the sensitive receptors at or above 50 mg/L in any
season.
Amine Spill
The CHEMMAP stochastic modelling study (APASA, 2014a) for the 1 hr surface 1,000
m3 amine spill event predicts the 1.8 mg/L dissolved amine concentration to extend
over 78 km to the northeast and over 70 km to the southwest of the release site over
both seasons. The probability of contact of the amine plume with Browse Island was
highest during the winter season at 2% and falls down to 1% over the entire year. The
single event worst case contact concentration was predicted to be 13.9 mg/L and
occurred in the winter period. Similar concentrations and probabilities of contact are
likely for the Heywood Shoals; however, the contact is likely to be of lower likelihood
and short duration. A spill of amine may drift over the closest two KEFs (Continental

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Slope Demersal Fish Communities and Ancient Coastline at 125 m depth contour),
however given these two receptors are located sub-surface in considerable water
depth, this is unlikely to lead to any environmental effects or damage given the
expected positive buoyancy of the plume.

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9.13.4 Description and Evaluation of Impacts and Risks

Table 9-81: Summary of Combined Hydrocarbon Spill Modelling Results for Sensitive Receptors with Contact above Moderate Exposure Thresholds and
Chemical Spill Modelling Results
Geographical Receptor Location Distance from EP HC Concentration Above Moderate Potential Potential
Operational Section Exposure Thresholds Exposure to Exposure
Area Ref. Amine > 1.8 to MEG >

Accumulated
[km] mg/L 859 mg/L

(Shoreline)

Entrained/
Dissolved
Floating
Key Benthic Communities
Browse Island 39 Section Yes Yes Yes Yes No
Echuca Shoal 61 7.2.1 Yes - Yes Yes No
Heywood Shoal 81 Yes - Yes No No
Cartier Islet 136 Yes No Yes No No
Seringapatam Reef 136 Yes - Yes No No
Goeree Shoal 144 Yes - Yes No No
Vulcan Shoal 146 Yes - Yes No No
Scott Reef 159 Yes No Yes No No
Ashmore Reef 169 Yes No Yes No No
Hibernia Reef 194 Yes - Yes No No
KEFs
Continental Slope Demersal Fish Communities 14 Section Yes - Yes Yes No
Ancient coastline at 125 m depth contour 41 7.2.3 Yes - Yes Yes No
Seringapatam Reef and Cmlth waters in the Scott Reef Complex 131 Yes - Yes No No
Ashmore Reef and Cartier Island and surrounding Commonwealth waters 134 Yes No Yes No No
Carbonate bank and terrace system of the Sahul Shelf 206 Yes - Yes No No
Canyons linking the Argo Abyssal Plain with the Scott Plateau 384 No - Yes No No
Pinnacles of the Bonaparte Basin 457 No - Yes No No
Mermaid Reef and Cmlth waters surrounding Rowley Shoals 523 No - Yes No No
Glomar Shoals 941 No - Yes No No
Exmouth Plateau 1,127 No - Yes No No
Canyons linking the Cuvier Abyssal Plain and the Cape Range Peninsula 1,256 No - Yes No No
Commonwealth waters adjacent to Ningaloo Reef 1,304 No - Yes No No

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Demersal slope and associated fish communities of the Central Western 1,747 No - No No No
Province
Western rock lobster 1,862 No - No No No
RAMSAR Wetlands
Ashmore reef national nature reserve 162 Section Yes No Yes No No
Roebuck bay 474 7.2.5 No No Yes No No
Eighty-mile beach 610 No No Yes No No
Commonwealth Marine Area
Commonwealth Marine Environment 0 Section Yes - Yes Yes Yes
- Kimberley multiple use zone 7.2.6
- Ashmore Reef recreational use zone & Sanctuary zone
- Cartier Island Sanctuary zone
- Oceanic shoals multiple use zone
WA Mainland Coastline
WA mainland coastline <200km Section Yes Yes Yes No No
- Camden Sound 7.2.7
BIAs and Habitat Critical for the Survival of a Species
Blue and pygmy blue whales Migration - 78 Section Yes - Yes Yes No
Foraging - 132 7.2.8.2 Yes - Yes No No
Humpback whale Migration - 145 Yes - Yes No No
Calving - 145 Yes - Yes No No
Resting - 145 Yes - Yes No No
Nursing - 145 Yes - Yes No No
Migration (north No - Yes No No
and south) -
327
Dugong Foraging (high Yes - Yes No No
density
seagrass beds)
- 168
Foraging - 176 Yes - Yes No No
Calving - 176 Yes - Yes No No
Breeding - 176 Yes - Yes No No
Nursing - 176 Yes - Yes No No
Australian snubfin dolphin Foraging - 187 No - Yes No No
Breeding - 190 No - Yes No No

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Foraging (high No - Yes No No

density prey) -
190
Calving - 190 No - Yes No No
Resting - 190 No - Yes No No
Indo-Pacific humpback dolphin Foraging - 190 No - Yes No No
Calving - 190 No - Yes No No
Breeding - 190 No - Yes No No
Foraging (high No - Yes No No
density prey) -
190
Significant No - Yes No No
habitat -
unknown
behaviour - 247
Indo-Pacific/spotted bottlenose dolphin Calving - 190 No - Yes No No
Foraging - 190 No - Yes No No
Breeding - 239 No - Yes No No
Flatback turtle Inter-nesting No - Yes No No
buffer - 268
Foraging - 344 Yes - Yes No No
Nesting - 302 No No Yes No No
Inter-nesting - No - Yes No No
356
Mating – 1,005 No - Yes No No
Migration No - Yes No No
corridor – 1,005
Aggregation – No - Yes No No
1,114
Green turtle Nesting - 23 Yes No Yes Yes No
Foraging - 43 Yes - Yes Yes No
Inter-nesting Yes - Yes No No
buffer - 121
Inter-nesting - Yes - Yes No No
169
Mating - 174 Yes - Yes No No
Migration No - Yes No No
corridor - 1,005

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Aggregation – No - Yes No No
1,114
Basking – No - Yes No No
1,130
Hawksbill turtle Foraging - 141 Yes - Yes No No
Inter-nesting Yes - Yes No No
buffer - 150
Nesting - 169 Yes No Yes No No
Nesting - 971 Yes No Yes No No
Mating – 1,005 No - Yes No No
Migration No - Yes No No
corridor – 1,005
Inter-nesting – No - Yes No No
1,005
Loggerhead turtle Foraging - 344 Yes - Yes No No
Inter-nesting Yes - Yes No No
buffer - 986
Nesting – 1,008 Yes No Yes No No
Nesting – 1,285 Yes No Yes No No
Inter-nesting – Yes - Yes No No
1,688
Olive ridley turtle Nesting – No No No No No
critical habitat -
177
Foraging - 344 Yes - Yes No No
Whale shark Foraging - 33 Yes - Yes No No
Foraging (high No - Yes No No
prey density) –
1,329
Dwarf sawfish Foraging - 203 No - Yes No No
Nursing - 416 No - Yes No No
Freshwater sawfish Pupping - 416 No - Yes No No
Foraging - 416 No - Yes No No
Nursing - 433 No - Yes No No
Green sawfish Foraging - 203 No - Yes No No
Pupping - 454 No - Yes No No
Nursing - 769 No - Yes No No
Red-footed booby Breeding - 59 Yes No Yes Yes No

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Greater frigatebird Breeding - 59 Yes No Yes Yes No

Lesser frigatebird Breeding - 60 Yes No Yes Yes No
Wedge-tailed shearwater Breeding - 61 Yes No Yes Yes No
Foraging (in No - No No No
high numbers)
– 1,741
White-tailed tropicbird Breeding - 68 Yes No Yes Yes No
Brown booby Breeding - 118 Yes No Yes No No
Lesser crested tern Breeding - 141 Yes No Yes No No
Little tern Resting - 142 Yes No Yes No No
Breeding - 245 No No Yes No No
Roseate tern Breeding - 142 Yes No Yes No No
Resting - 571 No No No No No
Fairy tern Breeding - 991 No No Yes No No
Bridled tern Foraging (in No - No No No
high numbers)
– 1,747
Sooty tern Foraging – No - No No No
1,772
Little shearwater Foraging (in No - No No No
high numbers)
– 1,826
White-faced storm petrel Foraging (in No - No No No
high numbers)
– 1,837
World Heritage Properties
Ningaloo Coast 1,283 Section No No Yes No No
Shark Bay 1,651 7.3.1.1 No No No No No
Commonwealth Heritage Places
Scott Reef and surrounds 155 Section Yes No Yes No No
Ashmore Reef National Nature Reserve 162 7.3.1.2 Yes No Yes No No
Mermaid Reef – Rowley Shoals 535 No - Yes No No
Ningaloo Marine Area - Commonwealth Waters 1,304 No - Yes No No
HMAS Sydney II and HSK Kormoran Shipwreck Sites 1,877 No - No No No
National Heritage Places
The West Kimberley 1,283 Section Yes No Yes No No
Barrow Island and the Montebello-Barrow Islands Marine Conservation 1,651 7.3.1.3 No No Yes No No
Reserves

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The Ningaloo Coast 1,877 No No Yes No No

Shark Bay, Western Australia 1,283 No No No No No
HMAS Sydney II and HSK Kormoran Shipwreck Sites 1,651 No - No No No
Underwater Cultural Heritage
TBA Section No - Yes No No
7.3.1.5
Marine Protected Areas
Commonwealth
Kimberley 111 Section Yes - Yes No No
Cartier Island 134 7.3.2 Yes - Yes No No
Ashmore Reef 162 Yes - Yes No No
Oceanic Shoals 321 Yes - Yes No No
Argo-Rowley Terrace 323 No - No No
Roebuck 480 No - No No
Mermaid Reef 523 No - No No
Joseph Bonaparte Gulf 604 No - No No
Eighty Mile Beach 788 No - No No
Dampier 950 No - No No
Montebello 1,047 No - No No
Gascoyne 1,277 No - No No
Ningaloo 1,304 No - No No
Shark Bay 1,588 No - No No
Abrolhos 1,781 No - No No
State
Lalang-garram / Camden Sound 182 Section No - No No
North Kimberley 188 7.3.2 No - No No
Rowley Shoals 567 No - No No
Eighty Mile Beach Marine Park 612 No - No No
Montebello Islands Marine Park/Barrow Island Marine Park/Barrow Island 1,097 No - No No
Marine Management Area
Muiron Islands Marine Management Area and Ningaloo Marine Park 1,283 No - No No
Shark Bay Marine Park 1,691 No - No No
Fisheries
Commonwealth Fisheries
North-west slope trawl fishery 0 Section Yes - Yes Yes Yes
Southern bluefin tuna fishery 0 7.3.3.3 Yes - Yes Yes Yes
Western tuna and billfish fishery 0 Yes - Yes Yes Yes

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Skipjack fishery 0 Yes - Yes Yes Yes

Northern prawn fishery 395 Yes - Yes No No
Western deepwater trawl fishery 1,072 No - Yes No No
WA State Fisheries
Mackerel Fishery 0 Section Yes - Yes Yes Yes
West Coast Deep Sea Crustacean 0 7.3.4.4 Yes - Yes Yes Yes
South West Coast Salmon 0 Yes - Yes Yes Yes
Northern Demersal Scalefish 0 Yes - Yes Yes Yes
Marine Aquarium and Specimen Shell 28 Yes - Yes No No
Abalone 28 Yes - Yes No No
Broome Prawn 28 Yes - Yes No No
Kimberley Prawn 47 Yes - Yes No No
Kimberley Gillnet and Barramundi 213 No - Yes No No
Pilbara Trap 477 No - Yes No No
Pilbara Fish Trawl 560 No - Yes No No
Nickol Bay Prawn 560 No - Yes No No
Onslow Prawn 920 No - Yes No No
Exmouth Gulf Prawn 1,263 No - Yes No No
West Coast Rock Lobster 1,272 No - Yes No No
Gascoyne Demersal Scalefish 1,470 No - Yes No No
Shark Bay Scallop 1,512 No - No No No
Shark Bay Prawn 1,512 No - No No No
Shark Bay Crab 1,670 No - No No No
Shark Bay Beach Seine and Mesh Net 1,685 No - No No No
West Coast Demersal Scalefish 1,765 No - No No No
Northern Territory Fisheries
Offshore Net and Line Fishery 537 Section No - Yes No No
Spanish Mackerel Fishery 537 7.3.3.5 No - Yes No No
Demersal Fishery 540 No - Yes No No
Timor Reef Fishery 569 No - Yes No No
Coastal Line Fishery 618 No - No No No
Indonesian and Timor-Leste Coastlines
Indonesia and Timor-Leste >300 Section Yes - Yes No No
7.3.7
Oil and Gas Industry
INPEX Inchys FPSO 17 Section Yes - Yes Yes No
Crux Platform (Future) 160 7.3.8 Yes - Yes No No

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Montara FPSO 188 Yes - Yes No No

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Physical Environment
Water Quality
Figure 9-29 presents the environmental fate of the modelled 80-day subsurface release
of 254,400 m3 of Prelude well fluids. The figure indicates approximately 10% of the
hydrocarbon volume will evaporate to air, less than 2% or 5,000 m3 forming a surface
slick over a large area, more than 80% of the hydrocarbon (200,000 m3) will decay
within 100 days from the outset of the release with entrained and dissolved
hydrocarbons in the water column peaking at the end of the 80-day period
(approximately 40% of the total released volume) then reducing to 16% of the total
hydrocarbon volume released within 20 days after spill cessation.

Figure 9-29: Predictions for the partitioning of oil mass over time through weathering
processes for a subsea blowout of Prelude condensate for 80 days (1,600,000 bbl)
(APASA, 2013)

The low residual volumes of floating oil will continue to weather, decay and diminish
through further partitioning between the water column, air and shore/ sediment
accumulation. The dissolved hydrocarbon fraction will have the greatest impact on
water quality due to the presence of compounds such as BTEX and PAHs, which are
known to be toxic to marine biota (refer to Biological Environment section below for a
discussion of these effects). BTEX compounds are not expected to persist in the
marine environment due to their volatility and will continually diminish due to
weathering and biodegradation once released into the environment. PAHs are less
volatile than BTEX due to their higher molecular weight/ more complex structures and
are expected to persist for longer. The concentrations of hydrocarbons in the water
column will decrease over time once the release has stopped due to processes such
as dispersion, dilution, physical and biological degradation, and evaporation. For short
duration release scenarios (i.e. diesel, HFO and condensate), these processes will
begin to reduce the total amount of hydrocarbons in the water column shortly after the
release.
MEG and amine spills may also adversely affect water quality to an extent. The MEG
PNEC of 859 mg/L was modelled to be contained within an 8 km distance from the
release location. MEG is readily biodegradable and its concentration will reduce

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significantly within days of the release. Refer to Section 9.9.2 for further impact
assessment on MEG in the marine environment.
Amine will affect a larger area than a MEG spill due to its impact threshold of 1.8mg/L,
which is forecast to extend over 78 km to the northeast and over 70 km to the
southwest. The product exhibits readily to inherent biodegradability and is not
anticipated to bioaccumulate and therefore is not persistent in the marine environment
(Nalco Champion n.d).
Sediment Quality (Subsurface)
Sediment quality is not expected to be significantly affected by any of the worst-case
scenarios that release hydrocarbons at the sea surface. Hydrocarbon contaminants
(e.g. PAHs) from such surface releases are unlikely to reach the seabed due to the
water depth and low natural sedimentation rates in the region. Hydrocarbon
contaminants from the worst case subsea releases (loss of well control) may
contaminate sediments by advective transport of the plume that will be formed during
the release (Romero et al. 2015). This is considered likely to occur for the loss of well
containment scenario due to the relatively long duration of the release. Any resulting
contamination will be concentrated around, and down-current from the wellhead. Due
to the low density and volatile nature of the hydrocarbon, weathered condensate is
unlikely to be deposited to the seabed. The diesel and HFO releases from a loss of fuel
from a vessel scenario have relatively low portions of volatiles, which are expected to
evaporate quickly following the release. The remaining diesel and HFO fractions may
sink to the seabed if exposed to considerable sedimentary particles, however this is
considered very unlikely to occur in the open sea due to the low density of the residual
hydrocarbons relative to seawater and the naturally low suspended solids and
associated sedimentation rates. Residual diesel and heavy fuel oils near shorelines
may be exposed to higher sediment loads and be more likely to sink. Stranding of
residual/persistent oils on shorelines may lead to long-term contamination of sediments
with high-molecular weight hydrocarbons. These compounds are typically much less
toxic than low-molecular weight hydrocarbons.
The surface releases of amine and MEG are not considered likely to affect sediment
quality due to the low inherent natural suspended solids, low sedimentation rates and
the properties of the amine and MEG constituents, which are reported to have low
organic carbon-water partition coefficient, KOC, indicating low adhesion/ high mobility
of those chemicals in sediments (NLM Toxnet Database). Additionally, the amine
plume will be buoyant due to lower density relative to sweater so it will remain in the
surface layers of the water column.
Air Quality
The gas plume from the worst-case loss of well containment scenario will result in a
gas cloud upon reaching the water surface. This potentially large gas cloud is expected
to disperse rapidly in the open, offshore environment. The formation of gas clouds can
pose a significant safety risk from the formation of explosive mixtures and asphyxiation.
Given the localised extent and open environment, this risk is considered to be very low
for the receiving environment.
The table below presents the risk assessment for the worst case in terms of impacts
emergency event (i.e. well LOC) for the physical environment, based on the worst case
outcome for any environmental receptor (i.e. water quality).

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Environmental Receptor

Consequence

Residual Risk
Likelihood
Physical Environment (Water, Sediment and
Massive B-Remote Yellow
Air Quality)

Biological Environment
Benthic Communities
Bare Sediments
Seabed releases of Prelude well fluids may result in impacts to water quality and
sediments in the vicinity of the release location (refer to sections Water Quality and
Sediment Quality above). The seabed in the Operational Area and surrounds is
characterised by bare sediments which host low density infaunal and epibenthic
communities of filter feeding and deposit feeding organisms. These fauna species may
be subject to acute and chronic toxic effects from exposure to hydrocarbons, however
the extent of the affected habitat is expected to be localised to the vicinity of the
release location. This bare sediment habitat is widely represented in the Timor Sea,
and the associated fauna assemblages are not considered to be particularly sensitive
or of high conservation value. Filter feeding benthic communities may be vulnerable to
entrained and dissolved hydrocarbons. Entrained hydrocarbons can be ingested by
filter feeders, leading to increased exposure due to accumulation of ingested oil
droplets (Payne & Driskell 2003). While typically less toxic than dissolved
hydrocarbons, entrained oil may still cause toxic effects and may also result in physical
impacts such as clogging of filter feeding organs, potentially resulting in reduced
feeding efficiency. Filter feeder, and sessile organisms in general, may be exposed to
concentrations of dissolved hydrocarbons that result in acute and chronic toxic effects.
The more diverse benthic communities in the ZPI are found in shallower waters (< 50
m depth) or in association with islands, shoals, reefs, banks and the shoreline of the
Australian, Indonesian and Timor-Leste mainlands. This diversity is due to ambient
conditions supporting a healthy presence of primary producers, such as zooxanthellate
corals, macroalgae and seagrasses and mangroves.
Modelling results from the loss of well containment, condensate, diesel and HFO
scenarios indicate that several offshore reefs and islands, banks and shoals, may be
contacted by hydrocarbons above adverse impact thresholds. Impacts on the primary
producer communities in these locations are discussed below.
Corals
Experimental studies and field observations in the aftermath of hydrocarbon spills for
corals indicate contact with hydrocarbons may result in impacts from no observable
injury through to complete or partial tissue death of the colony, with tissue death
occurring on the coral colony’s surface where oil has adhered (Johannes et al., 1972,
Jackson et al., 1989). Branching corals appear to be more sensitive to contact with
hydrocarbons than other species and growth forms (Johannes et al., 1972), however,
these are uncommon on intertidal reef flats and generally occur only in significant
abundance subtidally.
Subtidal corals avoid direct contact with surface oil slicks but can be exposed to the
entrained and dissolved hydrocarbon plumes when at the same depths. These

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hydrocarbon fractions are most likely to cause sublethal effects, such as polyp
retraction, changes in feeding, bleaching (loss of zooxanthellae), increased mucous
production resulting in reduction in growth rates and impaired reproduction (Negri and
Heyward, 2000). The planktonic stages (spawned gametes and larvae) of coral are
more susceptible to adverse effects from exposure to hydrocarbons because of their
tendency to float or remain near the water surface thus bringing them into direct
contact with surface slicks (Villanueva et al., 2008). In addition, the concentrations of
water-soluble fractions that inhibit fertilisation or are lethal to coral gametes are lower
than those for lethal or sublethal effects in adult colonies (Heyward et al., 1994; Negri
and Heyward, 2000). Coral planktonic stages of mass spawning species are largely
confined to a 1 to 3-week period after spawning which generally occurs in March/ April
but may occur twice a year for the coral colonies in the Timor sea. A spill outside of
these periods is of less concern for coral planktonic stages.
Compared to subtidal coral habitats, reef flat communities generally have the lowest
coral cover and lowest diversity of corals due to the harsh conditions for coral growth
i.e. regular tidal exposure and extensive wave action (particularly along the west coast
of Australia). As hydrocarbon ultimately floats to the sea surface, the most vulnerable
coral colonies to direct contact with hydrocarbon spills are intertidal corals found on a
reef flat, which are periodically exposed during low tides. As such, whilst the reef flat
habitat is the most vulnerable coral habitat to direct contact to spills, it is also regarded
as the least sensitive of the shallow coral habitats.
The intertidal and shallow water coral reef species at Browse Island, Heywood and
Echuca Shoals and other nearby reefs and shoals could potentially suffer sub-lethal
stress and, depending on the exposure time and concentration, potentially high rates of
mortality. The exposure time and concentration are a function of the location, including
the distribution of entrained and dissolved hydrocarbons throughout the water column,
the extent of the spill, the met-ocean conditions at the outset of the spill and in the days
and weeks following it. The extent of sub-lethal stress and mortality on coral species is
likely to be species and depth dependent with intertidal and shallow subtidal species
most likely to be impacted by hydrocarbon exposure, compared to their deeper
counterparts. These shallow water communities have shown that they can recover
quickly from natural mass mortality events. However, depending on the severity of the
spill, recovery may still take years.
Macroalgae and Seagrass
Although seagrass and macroalgae may be subject to lethal or sublethal toxic effects
including mortality, reduced growth rates and impacts to seagrass flowering, several
studies have indicated rapid recovery rates may occur even in cases of heavy oiling
(Burns et al.; Dean et al., cited in WEL, 2011).
Most seagrasses within the area that may be affected by the worst-case hydrocarbon
spill scenarios are subtidal, although there may be relatively small areas of intertidal
seagrasses along the WA coastline. Seagrass in the subtidal and intertidal zones will
have different degrees of exposure to hydrocarbon spills. Subtidal seagrass is unlikely
to be exposed to surface spilled hydrocarbons, as most hydrocarbons in subtidal
environments will be concentrated at the surface. Intertidal seagrasses are vulnerable
to smothering by floating oil slicks, which can lead to mortality if it coats their flowers,
leaves and stems (Dean et al. 1998; Taylor and Rasheed 2011). Long-term impacts to
seagrass are unlikely unless hydrocarbon is retained within the seagrass meadow for a
sustained duration (Wilson and Ralph 2011). Toxicity effects can also occur due to
absorption of soluble fractions of hydrocarbons into tissues (Runcie et al. 2010). The
potential for toxic effects of entrained hydrocarbons may be reduced by weathering
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processes that should serve to lower the content of soluble aromatic components
before contact occurs.
Like seagrasses, the potential impacts to macroalgae depend on the exposure
pathway; most macroalgae in the region are subtidal, although intertidal macroalgae
may be present. Studies of subtidal macroalgal assemblages exposed to fuel oil spills
have shown that impacts from exposure are slight (Edgar et al. 2002; Lobón et al.
2008). Effects of exposure to oil on intertidal macroalgae are more variable; some
studies reported little evidence of impacts (Díez et al. 2009), while others show
significant impacts (De Vogelaere and Foster 1994). Recovery of intertidal macroalgae
has been shown to occur faster in areas where oil has been left to degrade naturally
compared to areas subject to intensive clean-up operations (De Vogelaere and Foster
1994). The same applies to the amine spills from the facility which were predicted to
reach the closest sensitive receptors in only 2% of the cases above the defined impact
threshold.
Mangroves
Intertidal mangrove habitats occur throughout much of Kimberley, offshore islands,
Indonesia and Timor Leste and are highly susceptible to oil pollution (NOAA 2014).
Given the distance between potential release locations and the nearest mangroves,
any spilled hydrocarbons reaching mangroves will be highly weathered. Mangroves are
vulnerable to contact with floating hydrocarbons, which may coat prop roots and
pneumatophores (aerial roots that support oxygen uptake) (Duke and Archibald 2016).
Exposure can result in direct effects such as yellowed leaves, defoliation and mortality,
and indirect effects such as reduced recruitment and increased sensitivity to other
stressors (NOAA 2014). Like seagrasses, mangroves can also be impacted by
entrained and dissolved aromatic hydrocarbons either in the water or sediment.
Mangrove communities will not be impacted by the worst case modelled chemical spills
from Prelude due to the large separation distance, dilution and low toxicity and low
persistence of MEG and amine’s low toxicity.
The table below presents the risk assessment for the worst-case in terms of impacts
emergency events (i.e. well LOC, diesel or HFO) for benthic communities, based on
the worst-case outcome for any of the environmental receptors in this group.

Environmental Receptor
Consequence

Residual Risk
Likelihood

Benthic Communities (Bare Sediments,

Corals, Macroalgae and Seagrass and Major B-Remote Yellow
Mangroves)

Pelagic Communities (Plankton, Pelagic Fish and Invertebrates)

Plankton
Potential impacts to phytoplankton and zooplankton from the worst-case hydrocarbon
or chemical spills are expected to consist of short-term acute toxic effects. Planktonic
communities are characterised by relatively rapid turnover rates of short-lived biota.
The high turnover rate will lead to rapid recovery as the spilled hydrocarbons decay in
the environment. Within plankton communities, there is evidence from laboratory

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studies that some taxonomic groups, particularly zooplankton (e.g. copepods) may be
more sensitive to hydrocarbon pollution (Almeda et al. 2013; Jiang et al. 2010). Few
reliable studies have shown any impacts of hydrocarbon spills on planktonic
communities, with most studies concluding that impacts from hydrocarbon pollution
cannot be distinguished from natural variability (Abbriano et al. 2011; Davenport et al.
1982; Varela et al. 2006). Many marine species have planktonic larval phases (e.g.
corals, many species of fish). Organisms with planktonic larval phases typically
produce very high numbers of larvae. A worst-case credible spill may result in
increased mortality of planktonic larvae (which are subject to high natural mortality);
however, this is not expected to result in population, habitat or species scale impacts.
Pelagic Fish
Fish respire through gills, which may make them more vulnerable to dissolved
hydrocarbons than fauna with less permeable skins, such as cetaceans, marine
reptiles and birds. Despite this apparent vulnerability, fish mortalities are rarely
observed to occur due to hydrocarbon spills (Fodrie and Heck 2011; International
Tanker Owners Pollution Federation 2011), although recorded instances of fish
mortality from spills in confined areas (e.g. bays) exist. These observations are
consistent with fish moving away from hydrocarbons in the water (Hjermann et al.
2007). Stochastic modelling results for all surface spills indicated that hydrocarbons are
likely to be concentrated in surface layers. As a result, demersal fish are unlikely to be
directly affected unless near a subsea release, as they are typically concentrated
around seabed features e.g. shoals, banks and subsea KEFs. Pelagic fish are more
likely to encounter dissolved and entrained hydrocarbons above adverse exposure
thresholds but may move away from affected areas following detection.
Exposure of fish to hydrocarbons may results in acute and chronic effects and may
vary depending on a range of factors such as exposure duration and concentration, life
history stage, inter-species differences and other environmental stressors (Westera
and Babcock 2016). Early life history stages of fish (planktonic eggs and larvae) may
be more vulnerable to hydrocarbon pollution than juvenile and adults, as these early life
history phases cannot actively avoid water with high concentrations of hydrocarbons.
Fish embryos and larvae may exhibit genetic and developmental abnormalities from
long-term exposure to low concentrations of hydrocarbons (Fodrie and Heck 2011),
although such long exposures may not be representative of real-world conditions.
Exposures to PAHs have also been linked to increased mortality and stunted growth
rates of early life history (pre-settlement) of reef fishes, as well as behavioural impacts
that may increase predation of post-settlement larvae (Johansen et al. 2017). Given the
temporal and spatial scale of the worst-case credible spill scenarios (as shown by a
single deterministic run), and the typically high supply of eggs and larvae, it is unlikely
that any of the worst-case credible spill scenarios will result in significantly reduced
recruitment of fish due to impacts during early life history phases.
Environmental monitoring of pelagic and demersal fishes immediately following the
Montara oil spill indicated that despite the exposure to hydrocarbons, no adverse
effects were detected in fish (Gagnon and Rawson 2012, 2011). Further sampling and
testing over time indicated that fish captured in close proximity to the Montara wellhead
were comparable to those collected from reference sites (Gagnon and Rawson 2012,
2011). This conclusion is supported by studies of fish stocks following large-scale
hydrocarbon spills, which have shown relatively little evidence of reduced recruitment
at the scale of fish stocks/populations (Fodrie and Heck 2011).
MEG or amine spills will also have transient effects on water quality and as such are
not expected to adversely affect local fish communities at the population level.
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The table below presents the risk assessment for the worst-case in terms of impacts
emergency events for pelagic communities, based on the worst-case outcome for any
of the environmental receptors in this group.

Environmental Receptor

Consequence

Residual Risk
Likelihood
Pelagic Communities (Plankton, Pelagic Fish
Moderate B - Remote Dark Blue
and Invertebrates)

Key Ecological Features (KEFs)

Modelling study results indicated no KEFs will be exposed to adverse impact
thresholds for floating hydrocarbons, but several KEFs may be exposed to entrained
and dissolved hydrocarbons above adverse impact thresholds. KEFs with the closest
proximity to the credible spill sources that may experience contact above moderate
impact thresholds include (see Table 9-81):
• continental slope demersal fish communities
• ancient coastline at 125 m depth contour
• Seringapatam Reef and Commonwealth Waters in the Scott Reef Complex
• Ashmore Reef and Cartier Islands and surrounding Commonwealth waters.
The continental slope demersal fish communities and the ancient coastline at 125 m
depth contour are entirely sub-tidal. The relatively diverse benthic communities
associated with these habitats, such as filter feeding communities and demersal fish
assemblages may be impacted by dissolved and entrained hydrocarbon above
moderate exposure thresholds, which may result in acute or chronic toxic effects. KEFs
are most likely to be contacted by the subsea loss of well control scenario, due to the
large entrained hydrocarbon fraction. Modelling results indicated that no single
deterministic run affected the entirety of a sub-tidal KEF; most runs typically affected a
minor portion of any given KEF. Given the nature of the KEFs and the scale of potential
impacts, recovery of impacted parts of a KEF are expected to be facilitated by
movement and recruitment of biota from the unaffected areas.
Several offshore reefs and islands within KEFs were identified by the modelling study
results as potentially being contacted by hydrocarbons above adverse exposure
thresholds. These include Ashmore Reef and Cartier Island and Seringapatam Reef
and Commonwealth waters in the Scott Reef complex. Offshore reefs and islands
typically host light-dependent ecosystems characterised by benthic primary producers
and biological communities that are distinct from coastal islands and the mainland.
Potential impacts will be limited to submerged receptors only as floating oils were
predicted to contact any of these KEFs at concentrations well below the lower adverse
impact threshold at very low annual probabilities between 0.5% and 3%.
Environmental effects will be similar to those described for sub-tidal KEFs.
The table below presents the risk assessment for the worst-case in terms of impacts
emergency events for pelagic communities, based on the worst-case outcome for any
of the environmental receptors in this group.

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Environmental Receptor

Consequence

Residual Risk
Likelihood
KEFs Major B-Remote Yellow

Threatened and Migratory Species

Cetaceans and Dugongs
Marine mammals potentially present, their conservation status and any associated
BIAs within the ZPI are detailed in Section 7.2.8.
Cetaceans exposed to surface, entrained or dissolved aromatic hydrocarbons above
adverse exposure thresholds may suffer external oiling, ingestion of oil and inhalation
of toxic vapours (Deepwater Horizon Natural Resource Damage Assessment Trustees
2016). Cetaceans in coastal waters (e.g. coastal dolphin species and humpback
whales at the northern limit of their migration) are at lower risk of impacts than
cetaceans in offshore water due to the oil weathering before reaching coastal waters.
Skin contact with floating hydrocarbons could result in irritation and absorption and
potential for impact to eyes and airways. Inhalation of vapours or the ingestion of
hydrocarbons can potentially have lethal effects due to damage to the whale’s
respiratory and nervous systems. Baleen whales, such as blue whales and humpback
whales, are the most likely to be susceptible to hydrocarbon ingestion due to their
feeding through baleen plates including from near water surface. Toothed whales and
dolphins are less susceptible due to their ‘gulp’ feeding approach, often targeting
individual specific prey away from the sea surface (Woodside Energy Limited 2011).
However, cetaceans and dugongs are highly mobile, capable of long migrations, and
typically in low numbers/densities in the moderate exposure zone. Experimental and
field observations indicate that whales and dolphins may be able to detect and actively
avoid hydrocarbon slicks, but this may not always be possible and exposure to floating
oil may still occur (Smith et al. 1983, Geraci and St. Aubin 1990).
Vessel-based surveys of the Browse Basin area by the Centre for Whale Research
(Western Australia) Inc. between June and November 2008 recorded low numbers of
cetaceans in a broad survey area, with average densities of 0.00013 large cetaceans
(whales) per square kilometre (1 whale per 7,700 km2) and 0.026 small cetaceans
(dolphins) per square kilometre, or 1 cetacean in 39 km2 (Jenner, Jenner & Pirzl 2009,
cited in INPEX 2010). Given such sparse distributions, it is not anticipated that impacts
to a significant portion of the cetacean and other mammal populations would result if a
spill was to occur.
Dugongs are known to occur in coastal waters and around offshore islands within the
moderate exposure zones identified by the stochastic spill modelling. There is a paucity
of studies examining the effects of hydrocarbon spills on dugongs, although the direct
impacts of exposure to hydrocarbons may be similar to cetaceans. Like cetaceans,
dugongs are expected to be resilient to direct impacts due to their thick skin and
blubber. Suitable dugong habitat is associated with seagrass meadows, which are
typically restricted to shallow waters around the mainland coast and islands. The
distance of dugong habitat from the worst-case credible spill release locations means
that oil reaching dugong habitat will be highly weathered.

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The table below presents the risk assessment for the worst-case in terms of impacts
emergency events for cetaceans and dugongs.

Environmental Receptor

Consequence

Residual Risk
Likelihood
Cetaceans and Dugongs Moderate B-Remote Dark Blue

Reptiles
Stochastic modelling results indicated moderate exposure zones overlap the known
distribution of several species of marine turtles and sea snakes. Saltwater crocodiles
were also identified as potentially occurring within the adverse exposure zone; given
the preferred habitat for saltwater crocodiles are freshwater rivers and estuaries,
impacts to this species from the worst-case hydrocarbon spills are not considered
credible. Marine turtles may be exposed to floating hydrocarbons when at the sea
surface (e.g. breathing, basking etc.), and are not expected to actively avoid floating
hydrocarbon slicks (NOAA 2010). Exposure to floating or entrained hydrocarbons may
result in external oiling, which could result in impacts such as inflammation or infection
(Gagnon and Rawson 2010, Lutcavage et al. 1995; NOAA 2010). Given the large
portion of non-persistent hydrocarbons in Prelude condensate and well fluids, the loss
of diesel or heavy fuel oil scenarios are considered to pose the greatest risk of external
oiling. Dissolved hydrocarbons may result in toxic effects on marine turtles, however
their relatively impermeable skin reduces the potential for these impacts.
Stochastic modelling identified island and mainland shoreline habitats (sandy beaches
and inter-nesting habitat) that may be exposed to hydrocarbons above moderate
exposure thresholds. Some of these are classified as habitat critical for the survival of
marine turtles in the Recovery Plan for Marine Turtles in Australia (Commonwealth of
Australia 2017a) and BIAs as listed in Table 7-7. Of these, the critical nesting and inter-
nesting habitats for green turtles at Browse island have the highest probability to be
affected above moderate impact thresholds.
Several shoals and banks occur in the ZPI, which may be used as foraging areas by
marine turtles. Impacts to benthic habitats and biota at these shoals and banks may
result in a reduction of prey for marine turtles. A spill reaching critical nesting habitats
during peak periods to turtle nesting could result in impacts. With respect to floating oil,
given the distance of these locations from Prelude, worst-case credible spills of Prelude
well fluids, condensate, HFO or diesel reaching these areas will be highly weathered
and unlikely to result in impacts from an acute toxicity perspective, except for Browse
Island.
Sea snakes have similar exposure pathways to spilled hydrocarbons as marine turtles
(although sea snakes will not be exposed to shoreline hydrocarbon accumulation).
Potential impacts are expected to be comparable and may include irritation of eyes and
mucous membranes. Sea snake mortality has been linked to exposure to hydrocarbon
spills, with dead sea snakes recovered from the region of the Montara oil spill showing
high levels of petroleum hydrocarbons (including PAHs) in the trachea, lungs and
stomach (Gagnon 2009). These results are consistent with exposure through ingestion
and respiration of hydrocarbons. Ashmore Reef and Hibernia Reef are noted as being
one of the few sites where the critically endangered leaf-scaled sea snake and short-

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nosed sea snake have been recorded, along with other species of sea snake. Both the
leaf-scaled and short-nosed sea snakes have not been detected at Ashmore Reef
since 2001, despite increased biological survey effort. Both locations were identified by
the stochastic modelling as potentially being exposed to hydrocarbon above moderate
adverse exposure limits.
The table below presents the risk assessment for the worst-case in terms of impacts
emergency events for reptiles.

Environmental Receptor

Consequence

Residual Risk
Likelihood
Reptiles Major B-Remote Yellow

Seabirds and shorebirds

Seabirds and shorebirds are present in the ZPI (see Section 7.0 for details). Seabirds
are particularly vulnerable to hydrocarbon spills owing to high potential for contact with
the sea surface where they feed, rest or moult. Feeding by seabirds recorded in the
region involves snatching prey items from or below the water surface by paddling or
aerial diving, and these birds also rest on the ocean surface. Migrating and residential
shorebirds by contrast are less susceptible to severe oiling and associated physical
effects as they confine feeding to shorelines (Sholz et al. 1992; cited in Woodside
Energy Limited 2011) and they do not land on the water surface. In cases where the
hydrocarbon spill comes ashore large number of shorebirds may be impacted.
In the event of a spill, seabirds and shorebirds are likely to make contact with spilled
hydrocarbons due to the amount of time they spend on or near the surface of the sea
and on affected foreshores. Contact with hydrocarbon may impact a bird’s ability to fly
due to external and/ or internal exposure potentially leading to death by drowning,
starvation or predation. Hydrocarbon contamination affects the feathers insulation,
buoyancy and waterproofing properties and ultimately the bird’s survival. The
overriding behaviour of a bird with oiled feathers is preening to the exclusion of all other
normal activities. As an affected bird preens, it ingests and inhales hydrocarbons,
which can cause damage to internal organs such as the lungs, intestines and liver.
Suppression of the immune system can also occur and other effects include impacts to
reproductive success through decreased fertility of eggs and reduction in egg shell
thickness.
Specifically, estimates for the minimal thickness of floating oil that might result in harm
to seabirds through ingestion from preening of contaminated feathers, has been
estimated by different researchers at approximately 10g/m2 (French 2000) to 25g/m2
(Koops et al. 2004).
The main area of sensitivity for migratory birds are the Ashmore Reef and Cartier
Islands, which are recognised as particularly important for feeding migratory shore
birds during non–breeding periods. These islands are an important staging point during
the migration between the Northern Hemisphere and Australia. During October to
November and March to April large flocks of birds protected under the JAMBA, CAMBA
and ROKAMBA are more likely to be present in the area and sensitive to shoreline oil
contact. Browse Island, and Seringapatam and Scott Reefs are recognised as

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important habitat for seabirds. These locations, as indicated by modelling, will not be
affected to any adverse impact levels i.e. > 10g/m2 (French 2000).
The table below presents the risk assessment for the worst-case in terms of impacts
emergency events for seabirds and shorebirds.

Environmental Receptor

Consequence

Residual Risk
Likelihood
Seabirds and shorebirds Massive B-Remote Yellow

Socio-Economic and Cultural Environment

Commonwealth Heritage Places and Marine Protected Areas
Commonwealth Heritage Places and Marine Protected Areas overlap with the sensitive
receptors discussed in the Physical and Biological Environment sections above.
Several offshore islands and reefs listed as Commonwealth Heritage Places were
identified by the spill modelling results as potentially being contacted by hydrocarbons
above moderate exposure thresholds. These include:
• Ashmore Reef National Nature Reserve Commonwealth Heritage Place
• Scott Reef and Surrounds Commonwealth Heritage Place
• Mermaid Reef – Rowley Shoals Commonwealth Heritage Place
The environmental values of these reefs are primarily their outstanding natural values.
These have been discussed in the preceding sub-sections.
Modelling results of the worst-case credible spill scenarios indicated a range of
Commonwealth, state and territory marine parks may be contacted above moderate
exposure thresholds (Table 9-81). These parks contain a range of environmental
values such as marine biota, representative marine habitats and unique sea scapes
(e.g. KEFs). Environmental values for these marine parks are described in Section 7.0
and discussed above in Physical and Biological Environments. Refer to these sections
for discussion of potential impacts to these environmental values within marine parks.
The table below presents the risk assessment outcome for this receptor.

Environmental Receptor
Consequence

Residual Risk
Likelihood

Commonwealth Heritage Places and Marine

Massive B-Remote Yellow
Protected Areas

Fishing Industry
A number of commercial fisheries operate within the moderate exposure zone
determined from spill modelling results. The worst-case credible hydrocarbon spill

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scenarios may result in a range of impacts to commercial fishing activities, such as

(International Tanker Owners Pollution Federation 2011):
• displacement of fishing effort from areas affected by a spill or spill response activities
• damage to fish stocks due to mortality
• closure of fisheries by management agencies
• inability to sell catch due to perceived or actual fish tainting or contamination
• oiling of fishing gear, particularly by floating oil.
A significant hydrocarbon spill would likely result in the temporary closure of areas of
fisheries within the area of moderate exposure. The spatial extent and duration of the
closure would depend on the nature and scale of the pollution resulting from the
hydrocarbon spill. Given the large spatial extent of managed fisheries relative to the
area potentially contacted above moderate exposure thresholds for any single event, a
spill is unlikely to result in the complete closure of a fishery. Rather, the closure of
areas to fishing is more likely to result in the displacement of fishing effort during the
response and recovery phases. Displacement from productive fishing areas may result
in impacts to fishers such as increased costs and reduced catch per unit effort and
reduced income. Exposure of fish to hydrocarbons may result in tainting, which may
render landings unsuitable for human consumption. Tainting may occur even at low
levels of hydrocarbon exposure. Monitoring of fish for taint immediately following
capping of the Montara well detected differences between fish likely to have been
exposed to hydrocarbons, however these differences were not conclusively linked to oil
contamination and fell within the range of “normal” fish odours (Rawson et al. 2011).
Samples collected at the same monitoring locations two and four months after were not
distinguishable (Rawson et al. 2011). These results are consistent with other studies of
fisheries resources exposed to hydrocarbon pollution, which acknowledge the potential
for impacts to fisheries resources and have shown little potential risk for consumers if
suitable fisheries management actions are undertaken (Law and Hellou 1999; Law and
Kelly 2004). Fish caught in areas affected by a significant hydrocarbon spill may be
perceived as being of poorer quality, even if no decrease in quality is evident. This may
result in lower prices at the time of sale and subsequently lead to reduced income for
commercial fishers.
The table below presents the risk assessment outcome for this receptor.

Environmental Receptor
Consequence

Residual Risk
Likelihood

Fishing Industry Moderate B-Remote Dark Blue

Tourism and Recreation

There are currently no known tourism activities in the Operational Area, or immediate
surrounding areas, due to the remoteness and water depth of the area. Some tourism
activities may occur at the remote offshore islands and reefs within the ZPI. These
activities are expected to be exclusively nature-based tourism and impacts to the
environmental values associated with these islands and reefs may impact upon tourism
activities. Mainland coastline and islands will typically host more nature-based tourist

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activities than offshore islands. This activity is expected to be seasonal, with increased
visitation during the winter dry season months. Impacts to tourism activities are
expected to be minor based on the likelihood and nature of contact to environmental
values that support tourism activities. Impacts to these values may result in
displacement of tourism activity, introduction of temporary exclusion zones or
avoidance of areas with visible oil sheens, and a corresponding loss of revenue for
tourist operators (e.g. charter fishing cancellations due to fishery closures).
The table below presents the risk assessment outcome for this receptor.

Environmental Receptor

Consequence

Residual Risk
Likelihood
Tourism and Recreation Minor B-Remote Dark Blue

Defence
Defence activities within the offshore North Australian Exercise Area (NAXA) are
unlikely to be affected by the worst-case credible hydrocarbon spills. Activities may be
temporary displaced from areas where spill response operations are underway. This
would be highly localised and temporary in nature.
Shipping
Potential impacts to commercial shipping from the worst-case credible spill scenarios
are expected to be slight and consist of temporary displacement of other users from
areas where spill response activities are underway. These are expected to be
concentrated around the release location.
The table below presents the risk assessment outcome for defence and shipping.

Environmental Receptor
Consequence

Residual Risk
Likelihood

Defence and Shipping Minor B-Remote Dark Blue

Oil and Gas Industry

Petroleum activities in the region include drilling and pre-installation activities for the
future Shell-operated Crux facility, the INPEX-operated Ichthys facility and the Montara
development. Other exploration activities are expected to occur in the Timor Sea
throughout the life of the Prelude operations. Reduction in water quality as a result of a
worst-case credible spill may affect the operation of these facilities if seawater at the
facility is no longer suitable for intake (e.g. for use as cooling water or feed water for
RO water generation). This may result in impacts to routine operations such as
decreased production. A worst-case hydrocarbon spill response may result in
competition for vessels and potentially drilling rigs (if well intervention or a relief well is
required).
The table below presents the risk assessment outcome for the oil and gas industry.
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Environmental Receptor

Consequence

Residual Risk
Likelihood
Oil and Gas Industry Minor B-Remote Dark Blue

Indonesian and Timor Leste Coastlines

The spill modelling results indicate there is the potential for the well loss of containment
spill scenario resulting in contact with the Indonesian coastline. The probability of
floating film contact with the Indonesian Coastline was estimated at < 0.5% and
minimum arrival time of 64 days for those rare contact scenarios, with maximum local
accumulation of 3 kg/m2 for the worst replicate spill. Contact for entrained oil was also
predicted at 33% for the moderate exposure threshold. The probability of dissolved
hydrocarbon contact was predicted to be approx. 5% for the moderate exposure
threshold.
Given the relatively long time to contact, soluble aromatic hydrocarbon fractions are
unlikely to be present, leaving relatively low toxicity residual hydrocarbons such as
paraffins. Potential impacts may include smothering of coastal infrastructure (e.g.
aquaculture, fishing equipment), which may result in localised economic impacts.
The table below presents the risk assessment for the worst case in terms of impacts
emergency events for seabirds and shorebirds.

Environmental Receptor
Consequence

Residual Risk
Likelihood

Indonesian and Timor Leste Coastlines Major B-Remote Yellow

9.13.5 Risk Assessment Summary

The risk assessment summary in Table 9-82 is based on the worst case in terms of
consequences spill event, i.e. the loss of well control LOC.
Table 9-82: Emergency Events Evaluation of Residual Risks

Environmental Receptor
Consequence

Residual Risk
Likelihood

Evaluation – Unplanned Risks

Physical Environment Massive B-Remote Yellow
Biological Environment Major B-Remote Yellow
Socio-economic Environment Massive B-Remote Yellow

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9.13.6 ALARP Assessment and Environmental Performance Standards

Table 9-83: ALARP Assessment and Environmental Performance Standards

Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)

Elimination None identified N/A N/A N/A N/A N/A

Substitution Substitute MEG, Amine or No MEG and amine (MDEA) have been selected based N/A N/A N/A
HFO/IFO within MDO or on their performance and non-hazardous HES
LNG with less hazardous properties. MEG is classified as PLONOR and is
chemicals also considered as non-persistent in the
environment and does not bioaccumulate. Amine
(MDEA) is biodegradable and exhibits low toxicity.
Additionally amine is used in closed systems and is
not intended to be disposed to the marine
environment.
It is not practical for Shell to mandate vessel
specifications or requirements regarding fuel types
onboard offtake tankers visiting the Prelude FLNG
facility.
Engineering FLNG is double hulled Yes Prelude FLNG is double-hulled except for the area N/A N/A- Prelude FLNG is N/A
around the hull thrusters as purposefully designed. permanently installed
In addition, the condensate storage tanks are (moored) and
surrounded by ballast water tanks which provide commissioned at the time
additional protection in case of a hull breach. this EP commenced, and is
therefore not described in
further detail here as an
EPS
Engineering Condensate offloading Yes The MBC is designed to prevent oil spills and protect 11.1 Condensate offloading hose Records demonstrating
hoses have Marine the transfer system from damage in the event of a is equipped with a MBC presence of an MBC on the
Breakaway Coupling tanker breakout or an excessive pressure surge. condensate offloading
(MBC) hose.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)

Engineering Use of radars/ Automatic Yes Use of radars/ Automatic Identification System (AIS)/ 11.2 Product offtake tankers are AIS information shows
Identification System Automatic Radar Plotting Aid (ARPA) and assisted by Prelude infield offtake tankers being
(AIS)/ Automatic Radar associated alarms on FLNG, infield support vessels support vessels. assisted by Prelude infield
Plotting Aid (ARPA) and and supply vessels. support vessels.
associated alarms on This technology allows early identification and
FLNG, infield support notification of approaching vessels and is crucial in
vessels and supply minimising the risk of vessel-to-vessel collision.
vessels
All product off-loading activities are done in
accordance to the Prelude Terminal Information
Book (OPS_GEN_004647) which includes specific 11.3 Product offtake tankers are Pilot Competency
collision prevention procedures and measures piloted by competent marine Assurance
including: pilots to ensure safe
berthing/ offloading/ de-
• Controlled speed for all marine vessels in the berthing.
PSZ
• Ability for three way communication between
FLNG, infield support vessels and offtake
vessel
• The PSZ is patrolled by support vessels The FLNG supporting Marine Assurance records
11.4
• FLNG radar/ ARPA and associated alarms vessels are equipped with
monitored for approaching vessels suitable and operational
• Vessels follow pre-determined access routes to navigation and collision
the FLNG and assess environmental conditions avoidance equipment,
(wind, current and sea state) specifically:
• Contractual requirement for vessels to be
manned by competent crew • ARPA
• All contracted vessels employed are subjected • AIS
to a stringent assurance process, and • Radar, and/or
• Product offtake tankers are assisted by Prelude • Equivalent system.
infield support vessels and piloted by Prelude
FLNG marine pilots to ensure safe berthing/
offloading/bunkering/ de-berthing.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)

Administrative Exclusion zone around Yes As per section 616 of the OPGGS Act, a PSZ is 1.3 Compliance with PSZ as per Gazette notice of PSZ
and Procedural drill centre and FLNG established for the Prelude FLNG, moorings and drill Section 616 of the OPGGS
Controls centre. The gazetted PSZ prohibits all vessels other Act. Incident report form used to
than vessels under the control of Shell and those record breaches of PSZ
operated by authorised persons from entering or requirements.
being present in the area of the PSZ without the
consent in writing of NOPSEMA. This small area of
this established zone in the open ocean environment
is considered to be inconsequential to other marine
users.
Administrative Lifting procedures and Yes The Shell Australia Lifting and Hoisting Standard 11.5 All lifts are approved in line Records of PTW, lift plans,
and Procedural maintenance & inspection (OPS_PRE_010176) and Manual with the Prelude Lifting and training records and lifting
Controls of lifting equipment. (OPS_GEN_010724) are mandatory for all lifting Hoisting Standard including equipment register
operations on the FLNG. The standard which the required use of
specifies lifting requirements, performance PTW/risk assessment
standards and roles and responsibilities will be where applicable
implemented to reduce the risk of dropped objects
impacting subsea infrastructure potentially resulting
in damage or at a worst case, a loss of well control
event.
Administrative FLNG and Vessel Yes The purpose of these procedures is to ensure that 11.6 The FLNG and contracted Assurance and
and Procedural Bunkering Procedures for good practice and industry standards are applied marine support vessels will maintenance records.
Controls Hydrocarbons and during bunkering operations. Implementation of have dry-break couplings,
Chemicals these procedures will minimise the risk of a spill inspected and certified
incident through e.g. both facilities prepared for bunkering hoses, and this
bunkering, drains plugged, approved bunker plan for equipment will be
specified volumes, designated receiving tanks and maintained.
agreed pumping rates, direct communication
between all involved and supervision at both ends 11.7 No spills to water as a result Incident records
and availability of spill kits onboard each of bunkering activities.
vessel/facility.

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Hierarchy of Control Measure Adopted? Justification EPS # Environmental Measurement Criteria

Controls Performance Standard
(EPS)

Administrative SOPEP for vessels 49 Yes SOPEP shall be in place for all marine support 11.8 Vessels shall have a current A valid SOPEP for relevant
and Procedural vessels as required by class in accordance with as SOPEP onboard to respond vessels is in place
Controls per AMSA Marine Order 91. to small spills
Administrative Vessel anchoring and Yes No support vessel anchoring in the Operational Area 11.9 No support vessel Records verify no breaches
and Procedural mooring plan except in emergency situations or under issuance of anchoring in the Operational of anchoring procedures in
Controls a specific permit by Shell. Area except in emergency the Operational Area.
situations or under issuance
of a specific permit by Shell.

Administrative Subsea control operators Yes Subsea control operators are trained and competent 11.10 Subsea control operators Competency assurance
and Procedural are competent in the operation and monitoring of the hydrocarbon are competent in the records
Controls system. operation and monitoring of
the hydrocarbon system

Administrative NOPSEMA accepted Yes Maintenance of well integrity is a key requirement to 11.11 Accepted WOMP in place WOMP acceptance letter
and Procedural WOMP avoid loss of well control. The wells at Prelude are for Prelude wells to manage
Controls covered by NOPSEMA accepted Well Operations risks associated with well
Management Plan (WOMP) that details key controls operations
in place for the duration of the well lifecycle.
In accordance with the OPGGS (Safety) Regulations
Administrative NOPSEMA accepted Yes 2009, all key activities will be undertaken in 11.12 Accepted safety case in Safety case acceptance
and Procedural safety case accordance with the accepted Prelude safety case. place for Prelude to manage letter
Controls risks associated with
operations

49 Advice from the Recognised Organisation will be followed and updates made where required, where there is any variation to the this control measure which may be applicable to the Prelude FLNG.

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9.13.7 Acceptability of Risks

Table 9-84: Acceptability of Risks – Emergency Events
Receptor Receptor Sub- Acceptable Level Are the Acceptability Assessment
Category category of Impact Impacts of
an
Acceptable
Level?
Physical Water quality Limited Yes Weathering data indicates low residual
Environment environmental volumes of floating oil will continue to
impact to water weather, decay and diminish through
quality and quality is partitioning between the water column, air
maintained so that and shore/ sediment accumulation.
biodiversity, The dissolved hydrocarbon fraction will have
ecological integrity, the greatest impact on water quality due to
social amenity and the presence of compounds such as BTEX
human health values and PAHs. BTEX compounds are not
are protected. expected to persist in the marine
environment due to their volatility and will
continually diminish due to weathering and
biodegradation once released into the
environment. PAHs are less volatile than
BTEX due to their higher molecular weight/
more complex structures and are expected
to persist for longer. The concentrations of
hydrocarbons in the water column will
decrease over time once the release has
stopped due to processes such as
dispersion, dilution, physical and biological
degradation, and evaporation.
Sediment Limited Yes Sediment quality is not expected to be
quality environmental significantly affected by any of the worst-
impact to sediment case scenarios that release hydrocarbons at
quality and quality is the sea surface. Hydrocarbon contaminants
maintained so that (e.g. PAHs) from such surface releases are
biodiversity, unlikely to reach the seabed due to the water
ecological integrity, depth and low natural sedimentation rates in
social amenity and the region.
human health values Residual diesel and heavy fuel oils near
are protected. shorelines may be exposed to higher
sediment loads and be more likely to sink.
Stranding of residual/persistent oils on
shorelines may lead to long-term
contamination of sediments with high-
molecular weight hydrocarbons. These
compounds are typically much less toxic
than low-molecular weight hydrocarbons.
Biological Benthic Limited Yes Modelling results from the loss of well
Environment communities environmental containment, condensate, diesel and HFO
impact which directly scenarios indicate that several offshore reefs
impacts bare and islands, banks and shoals, may be
sediment benthic contacted by hydrocarbons above adverse
habitats outside of impact thresholds.
the Operational Area
as a result of the Shallow water corals communities have
petroleum activities shown that they can recover quickly from
which adversely natural mass mortality events. However,
effects biological depending on the severity of the spill,
diversity or recovery may still take years.
ecological integrity. Although seagrass and macroalgae may be
subject to lethal or sublethal toxic effects

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Receptor Receptor Sub- Acceptable Level Are the Acceptability Assessment

Category category of Impact Impacts of
an
Acceptable
Level?
Limited including mortality, reduced growth rates and
environmental impacts to seagrass flowering, several
impacts to high- studies have indicated rapid recovery rates
value sensitive may occur even in cases of heavy oiling
benthic communities
(corals, macroalgae, Mangrove communities will not be impacted
seagrasses and by the worst case modelled spills due to the
mangroves) large separation distances between Prelude
associated with and the intertidal mangrove habitats found
named reefs, banks along the Kimberley coastline, offshore
and shoals. islands, Indonesia and Timor Leste.

Pelagic Limited Yes Potential impacts to phytoplankton and

communities environmental zooplankton from the worst-case
(Non- impact leading to hydrocarbon or chemical spills are expected
Threatened or adverse effect on to consist of short-term acute toxic effects.
Migratory) pelagic Planktonic communities are characterised by
communities, relatively rapid turnover rates of short-lived
populations, habitats biota. The high turnover rate will lead to rapid
or spatial distribution recovery as the spilled hydrocarbons decay
of a species. in the environment.
Exposure of pelagic fish to hydrocarbons
may results in acute and chronic effects and
may vary depending on a range of factors
such as exposure duration and
concentration, life history stage, inter-species
differences and other environmental
stressors. Studies of fish stocks following
large-scale hydrocarbon spills, which have
shown relatively little evidence of reduced
recruitment at the scale of fish
stocks/populations.
KEFs Limited impact to Yes The continental slope demersal fish
environmental communities and the ancient coastline at
values of KEFs 125 m depth contour are entirely sub-tidal.
The relatively diverse benthic communities
associated with these habitats, such as filter
feeding communities and demersal fish
assemblages may be impacted by dissolved
and entrained hydrocarbon above moderate
exposure thresholds, which may result in
acute or chronic toxic effects.
Modelling results indicated that no single
deterministic run affected the entirety of a
sub-tidal KEF; most runs typically affected a
minor portion of any given KEF. Given the
nature of the KEFs and the scale of potential
impacts, recovery of impacted parts of a KEF
are expected to be facilitated by movement
and recruitment of biota from the unaffected
areas.
Threatened No significant Yes Shell has identified the potential for
and Migratory impacts to listed hydrocarbon pollution, and potential
Species Threatened consequential habitats degradation for to
(Endangered and listed threatened or migratory MNES fauna
Vulnerable) or populations from a large scale hydrocarbon

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Receptor Receptor Sub- Acceptable Level Are the Acceptability Assessment

Category category of Impact Impacts of
an
Acceptable
Level?
Migratory MNES release as a major environmental risk. Shell
fauna populations. has applied a range of controls that are
Management of intended to reduce the likelihood of such a
aspects of the release occurring, and mitigative controls to
project must be understand and reduce the severity of
aligned to impacts should such as release occur.
conservation advice, Large-scale hydrocarbon releases pose a
recovery plans and significant safety risk for Shell personnel,
threat abatement and considerable effort will be applied to
plans, including for reduce the inherent likelihood of large-scale
bird and marine hydrocarbon releases occurring.
turtle species.

Ramsar Limited Yes Shell considers large-scale releases of

Wetlands environmental hydrocarbons from Prelude to be
impacts to unacceptable. Such spills have a potential to
ecological values of result in significant environmental impacts.
Ramsar wetlands Consequently, Shell will apply its
considerable experience and knowledge in
Commonwealth Limited Yes the offshore petroleum industry to ensure
Marine Area environmental such a release never occurs from Prelude.
impacts to the
Commonwealth Shell has applied a conservative approach to
Marine Area (refer to the identification and modelling of the
Table 8-1) credible worstcase hydrocarbon spills. This
information was used to inform the
WA mainland Limited Yes evaluation of the environmental impacts and
coastline environmental risks, and is consistent with the
impacts to mainland precautionary principle.
coastline. Shell will implement industry standard
Socio- Commonwealth Limited Yes controls to manage the risk of unplanned
economic Heritage environmental hydrocarbon spills through this EP and
Environment Properties impacts to defined associated OPEP commensurate to the
heritage values nature and scale of the hydrocarbon pollution
risks Prelude operations.
Marine Limited Yes
Protected environmental
Areas impacts to
ecological values of
Marine Protected
Areas
Fisheries No interference with Yes
fishing to a greater
extent than is
necessary for the
exercise of right
conferred by the
titles granted to
carry out petroleum
activities.
Tourism & No negative impacts Yes
recreation to nature-based
tourism resources
resulting in
demonstrated loss
of income.

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Receptor Receptor Sub- Acceptable Level Are the Acceptability Assessment

Category category of Impact Impacts of
an
Acceptable
Level?
Defence & No interference with Yes
shipping defence activities as
directed by the
Department of
Defence.
No interference with
navigation to a
greater extent than
is necessary for the
exercise of right
conferred by the
titles granted to
carry out petroleum
activities.
Oil and Gas No interference with Yes
industry other titleholders to
a greater extent than
is necessary for the
exercise of right
conferred by the
titles granted to
carry out the
petroleum activities
Indonesian & No impacts to Yes
Timor Leste Indonesian or Timor-
Coastlines Leste coastlines or
nearshore
environments are
acceptable.

A comprehensive assessment of the risks from the worst-case credible spill scenarios
arising from Prelude Operations has been undertaken. Globally, Shell is experienced in
the design, installation and decommissioning of similar developments and understands
the impacts and risks that may arise from these worst case credible spill scenarios.
Shell has undertaken environmental studies, numerical modelling and consultation to
identify the environmental receptors that may be affected and understands the nature
and implications of potential hydrocarbon pollution. These studies, along with Shell’s
organisational experience, allows a high degree of confidence to be placed in the
outcomes of the assessment of the risks.
Principles of ESD
The risks and impacts from the worst-case credible spill scenarios are inherently
inconsistent with some of the principles of ESD based on the following:
• environmental resources and sensitivities may be significantly impacted in the event a
worst-case credible spill, and
• a worst-case credible spill may prevent others exercising their right to access
environmental resources.
Shell will apply a range of controls to ensure that a worst-case credible spill from the
Prelude project never occurs. These include a range of industry best practices that
have been developed through extensive industry experience, including the lessons

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learned from significant unplanned releases such as the Macondo and Montara well
blowouts. Following successful application of these controls, Shell considers the
residual risk to be consistent with the principles of ESD. This consistency is achieved
by:
• developing natural resources in an environmental responsible manner, resulting in
income for government, generation of Australian jobs, and developing an increased
understanding of the Timor Sea environment.
• application of the precautionary principle in the assessment of hydrocarbon spill
scenarios by:
o using worst-case credible spill scenarios. Industry statistics indicate the vast
majority of unplanned spills are significantly smaller than the worst-case credible
spills.
o using a stochastic modelling approach for numerical modelling of the worst-case
credible spill scenarios that includes a large number (hundreds) of deterministic
runs covering a range of metocean conditions.
o using environmentally conservative adverse exposure zone thresholds.

Relevant Requirements
Management of the impacts and risks from unplanned hydrocarbon spills are
consistent with legislative requirements, including:
• compliance with international maritime conventions, including:
o STCW Convention
o SOLAS Convention
o COLREGS
o MARPOL: Annex I: prevention of pollution by oil and oily water.
• compliance with Australian legislation and requirements, including:
o Navigation Act 2012 and Protection of the Sea (Prevention of Pollution from Ships)
Act 1983:
 Marine Order 21 (Safety of Navigation and Emergency Procedures
 Marine Order 27 (Radio Equipment)
 Marine Order 30 (Prevention of Collisions)
 Marine Order 71 (Masters and Deck Officers)
 Marine Order 91 (Marine pollution prevention – oil).
o OPGGS Act 2006 and OPGGS (E) Regulations:
 accepted WOMPs for all well activities, including drilling, operation, suspension
and abandonment
 accepted EP and OPEP for all petroleum activities associated with the Prelude
project.
o Implementation of recognised industry best practices, such as:
 design, construction and operation of Prelude infrastructure in accordance with
recognised industry standards
 mutual aid agreement in place with other petroleum operators to assist with
drilling rig availability for relief well drilling

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 agreements in place with oil spill response service providers

 development of SIMOPS plans for activities that may interact with the Prelude
FLNG facility.
Matters of National Environmental Significance
Commonwealth Marine Environment
Table 9-85 provides a summary of the alignment between managing of the emergency
events aspect at Prelude with the relevant MNES acceptability considerations listed in
EPBC Management Plans/Recovery Plans/Conservation Advices.

Table 9-85: Summary of Alignment of the Impacts from the Emergency Events associated
with the Prelude Petroleum Activities to Relevant Requirements for MNES

Matters of National MNES Acceptability Demonstration of Alignment as

Environmental Considerations (EPBC Relevant to the Project
Significance Management Plans/Recovery
Plans/Conservation Advices)
Threatened and Migratory Emergency events due to loss of Shell has identified the potential for
Species – Marine containment are not considered to be hydrocarbon pollution, and potential
Mammals acceptable to Shell. In the event of consequential habitats degradation, from
such an incident, the relevant EPBC large-scale hydrocarbon releases as a
Threatened and Migratory Management Plans, Recovery Plans significant environmental risk. Shell has
species - marine reptiles and Conservation Advice applied a range of controls that are
Threatened and Migratory documentation will be consulted based intended to reduce the likelihood of such a
species - sharks and rays on the nature/scale of the spill and the release occurring, and mitigative controls
determination of the potentially to understand and reduce the severity of
impacted environmental sensitivities to impacts should such a release occur.
ensure mitigation and recovery efforts
are in alignment. Refer to Table 7-6 for
Threatened and Migratory full list of potential plans at the time of
species - birds writing this EP. The relevant
databases will be checked at the time
to ensure currency and any relevant
inclusions will be made.

Commonwealth Marine
Environment

External Context
There have been no objections or claims raised by Relevant Persons to date around
the emergency events aspect. Shell’s ongoing consultation program will consider
statements and claims made by stakeholders when undertaking further assessment of
impacts.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, controls and EPSs which will be implemented,
are consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements. Shell has, and will continue to maintain, an
appropriate spill response framework, which includes regular testing of the response
arrangements as per Section 10.7.
Acceptability Summary
The assessment of impacts and risks from the worst-case credible unplanned
hydrocarbon spills determined the residual impact and risk rating is Yellow (Table

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9-82). Given the significant consequence of the risks associated with these worst-case
hydrocarbon spills, Shell has undertaken an extensive, conservative risk assessment
and will apply a range of controls consistent with relevant requirements and industry
best practice.
As outlined above, the acceptability of the impacts and risks from unplanned spills
associated with Prelude operations has been considered in the context of:
• The established acceptability criteria for the emergency events aspect
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
Based on the points discussed above, Shell considered the impacts and risks from
worst case Prelude emergency events to be acceptable following the application of the
controls outlined in the ALARP Demonstration above.

9.13.8 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

No unplanned release of hydrocarbons Incident reports associated with spills

or chemicals to the marine environment which initiated the ERT and/or IMT.
as a result of loss of containment from:
• subsea infrastructure,
• during storage and offloading,
• refuelling,
• vessel collision or
• bulk transfer or lifting.

9.14 Oil Spill Response Strategies

9.14.1 Spill Impact Mitigation Assessment

As described in the SIMA presented in the OPEP, not all response strategies are
applicable for every spill scenario. It is considered that a combination of response
strategies may be required to implement an effective response.
In all spill scenarios (Section 9.13.1) source control and monitor and evaluation spill
response strategies will be implemented. For condensate and diesel releases the
success of various response strategies is considered to be limited based on the
expected spreading, dispersion and evaporation rates in the marine environment
making certain strategies such as contain and recover and surface dispersant
application ineffective. Whereas for HFO spills they may be implemented as primary or
secondary response strategies.

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The applicability of all spill response strategies are assessed in the strategic SIMA
presented in the OPEP. An ALARP assessment of the oil spill response strategies
described in the OPEP are presented in Table 9-86.
Capability, readiness and implementation requirements for the specific spill response
strategies are addressed in the OPEP (HSE_PRE_013075), which includes control
measures and EPSs around the required level of performance of each response
strategy, and hence are not repeated in this EP.

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Table 9-86: ALARP assessment of oil spill response capability

Oil Spill Response Resources Environmental gain from Alternatives ALARP assessment
Strategy increasing or improving considered
resources
Source Control
Site survey Documents: Browse Basin A site survey involves the use of a Additional vessels A vessel equipped to undertake the site survey is
Source Control Contingency vessel equipped with an ROV to equipped with ROV’s expected to take approximately 7-10 days to mobilise.
Plan conduct visual observations of the would not result in The vessel to undertake the site survey would be
Source Control Equipment well and surrounding subsea increased benefit for sourced from within Australia using Shell’s established
Mobilisation Plan infrastructure, following the loss of planning source vessel contracting procedures. The cost of maintaining a
containment event. control activities. vessel with full ROV spread and ROV crew at all times to
Equipment: Vessel equipped The information gathered is used to
with ROV and tooling undertake a site survey is considered to be grossly
enable further source control disproportionate given that several vessels with ROVs
Personnel: Subsea Intervention planning and establish those source
Group/Source Control Branch could be made available on short notice within the
control activities that could be
implemented. A single vessel with a region.
single ROV is required to conduct The following well and subsea tree valves are fail-safe
the site survey. Multiple vessels closed valves (SCSSSV, PMV, PWV and PSDV). With
and/or ROV’s would not result in a the subsea tree still connected, if there is a leak then the
better environmental outcome. initial response would be to attempt to isolate the failure
If the failure can be immediately by remotely functioning one or more valves from the
isolated remotely then this is the facility. There is also some ROV intervention capability.
quickest response to reduce the
environmental impact.

Deployment of Documents: Browse Basin Access to the SFRT/SIRT to Consideration was Based on its location in WA, the AMOSC SFRT
SFRT/SIRT and subsea Source Control Contingency enable intervention in the event of given to moving the (located in Perth) would be mobilised as the primary
dispersant injection Plan a loss of well control scenario will AMOSC SFRT to control with the SIRT located in Norway/Brazil as a
(SSDI) Source Control Equipment also enable SSDI capability. SSDI Broome to from Perth redundancy. As described in the row above, a vessel
Mobilisation Plan will increase the entrainment of to enable for faster equipped to undertake the site survey is expected to
hydrocarbons in the water column deployment however, take approximately 7-10 days to mobilise therefore the
Equipment: AMOSC Subsea it is owned by
First Response Toolkit (SFRT) thereby reducing the presence of timeframe for mobilisation of the SFRT is not a limiting
hydrocarbons at the sea surface industry (others may factor and improving this timeframe would not result in
including 500 m3 of Dasic Slick also need the
gone NS, mobilised to Broome in that can present environmental an environmental benefit.
impacts. The application of subsea equipment in other
6 days. areas) and as it is not
dispersant also has benefits over
surface application in that it can on critical path there

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Oil Spill Response Resources Environmental gain from Alternatives ALARP assessment
Strategy increasing or improving considered
resources
OSRL Subsea Incident reduce volatile organic compounds is little value to be
Response Toolkit (SIRT) at the sea surface making it safer gained by such.
mobilised to Broome. for responders to access the area
Personnel: for further source control activities.
Subsea Intervention Where surface application of
Group/Source Control Branch, dispersant can only be applied in
Shell’s Well Control Virtual daylight hours, SSDI can occur 24
Emergency Response Team hours a day. The volume of
(WC VERT) available in 24 dispersant associated with the
hours. SFRT can be replenished from
various stockpiles located within
AMOSC (SFRT) and Australia and Internationally.
Oceaneering (SIRT) personnel
available in 24 hours.
Relief well drilling Documents: Prelude Well Improving the timeframes to drill a The relief well Compliance with Shell’s global standards for well
As described in Section Operations Management Plan relief to will reduce the volume of injection spool design integrity to assure mechanical and functional
9.13.1, due to the (WOMP) hydrocarbons released to the (RWIS) is a spool integrity for all anticipated loads throughout the life of
presence of the Subsea Prelude Safety case marine environment. piece with side the well. These standards meet or exceed current
Xmas Tree, the primary Browse Basin Source Control outlets installed International and Australian standards.
method of source Contingency Plan below the BOP of The APPEA MoU allows the signatories to share rigs,
control is the drilling of a the relief well to equipment, personnel and services to assist other
Browse Basin Exploration and enable the
relief well. Appraisal Well Control operators in the event of a well blowout. This would
connection of more potentially enable Shell to source a suitable relief well
Contingency Plan including relief surface pumping
well locations MODU in a quicker timeframe, and would also provide
resources. These access to additional equipment, personnel and services.
Relief Well Manual additional resources Access to source control specialists is not considered a
Well Kill Modelling & Analysis can deliver greater limiting factor.
APPEA MoU kill fluid rates to the
Equipment: MODU to drill relief relief well. As all
well and kill the well in 80 days, Prelude wells can
kill fluid & pumping equipment, be killed with the
tubulars, ranging equipment. pumping capacity of
standard MODU,
Personnel: Shell Relief Well
use of the RWIS
Task Force 24-72 hours.
would not result in a
faster well kill and

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Oil Spill Response Resources Environmental gain from Alternatives ALARP assessment
Strategy increasing or improving considered
resources
Specialist personnel from Wild subsequent
Well Control and Boots and environmental
Coots Various locations benefit.
internationally +72 hours.
Monitor and Evaluate
Modelling (oil spill Processes: Oil spill trajectory modelling can be N/A No alternative or additional controls have been
trajectory, fate & AMOSC call-off procedure commenced using AMOSC call off identified that could improve this response.
weathering, met ocean Equipment: contract with RPS group within 2
data, satellite imagery) hours of IMT being notified of the
ADIOS2 on IMT PCs spill. The data would be used to
In-house deterministic modelling inform IAPs and confirm the
Personnel: selection of other response
Shell Geomatics team strategies in the following days.
Therefore, there is no
environmental gain in improving
the activation timeframe.
Surveillance - vessel Processes: N/A Several support vessels will be N/A Increasing vessel surveillance capability is not
Equipment: FLNG support present in WA-44-L. Shell has a considered to be warranted based on the limitations
vessels contract with marine vessel associated with visual observations made from a vessel
Personnel: Trained ISV crew contractors to provide additional platform. Aerial surveillance in conjunction with
vessels for oil spill response deployment of tracking buoys is a more effective
activities if required. There is no method of obtaining situational awareness. Vessel
environmental gain from providing surveillance can be undertaken through the use of
additional vessels. existing FLNG support vessels.
Surveillance - aerial Processes: Third party call-off Shell has third-party call off Personnel trained in Untrained aerial observation opportunities exist via
contract contracts for helicopters and fixed aerial observation Shell crew change helicopters. This in conjunction with
Aerial surveillance observation wing aircraft. These aircraft can be could be on standby tracking buoys and other monitor and evaluate data is
log ready for mobilisation in 4-8 hours. in order to provide expected to provide sufficient information for the IMT in
Equipment: N/A Trained aerial observers are higher quality data the 1st 24 hours, until such time as trained aerial
available within 24 hours. to the IMT. observers are available.
Personnel: Trained aerial However, in the 1st
observers 24 hours the spill it
(AMOSC/AMSA/OSRL) is likely to cover a
relatively small

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Oil Spill Response Resources Environmental gain from Alternatives ALARP assessment
Strategy increasing or improving considered
resources
geographical
location close to the
release point.
Therefore, initial
untrained
observations are
considered to be
adequate given the
other data available
to the IMT such as
spill modelling,
tracker buoy data
etc.
Tracking buoys Processes: N/A Tracker buoys are available for Access to additional No alternative or additional controls have been
Equipment: Tracking buoys immediate deployment from a buoys is available identified that could improve this response.
Personnel: Trained ISV/FLNG variety of locations including the from the shared
crew for tracking buoy Prelude FLNG. No environmental stockpile located in
deployment benefits can be gained by Broome.
increasing the number of buoys
available or time to deploy.
Surface Chemical Dispersant
Vessel based dispersant Processes: Shell Surface Based on the existing capability, N/A In the event of a spill that was amenable, surface
application Dispersant Application Guide Shell could commence vessel application of dispersant from vessels can be
Equipment: 5 m3 Dasic based dispersant application implemented immediately upon approval. In the event
Slickgone and AFEDO spray set immediately subject to AMSA that additional stockpiles of dispersant are required
on each ISV (3 vessels in field or approval (where relevant). they can be accessed from stockpiles in various
en-route) Additional supplies of dispersant locations across Australia.
Personnel: ISV personnel trained can be obtained from stockpiles on
in vessel application techniques the Australian mainland.

Fixed Wing Aerial Processes: Shell Surface Pre-positioning of aircraft and Additional costs Shell has access to AMSA fixed wing aircraft wheels up
Dispersant (FWAD) Dispersant Application Guide. personnel (air attack supervisor) in associated with pre- in 4 hours and first implementation within 36 hours with
application AMOSC/OSRL call-off particular could enable a faster positioning aircraft supporting monitoring aircraft.
procedure. response time resulting in quicker and personnel are

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Oil Spill Response Resources Environmental gain from Alternatives ALARP assessment
Strategy increasing or improving considered
resources
Equipment: N/A application of dispersant with more estimated to be in Surface application of dispersant using vessels can be
Personnel: Air attack supervisors oil treated and hence an overall the order of 10s of implemented much faster and therefore the costs
and pilots. environmental benefit. thousands of dollars associated with increasing FWAD capability are
per day and are considered to be grossly disproportionate given the
considered to be risk.
grossly
disproportionate
given the access to
vessel-based
dispersant
application.
Contain and recover
Containment and Processes: Shell Offshore Increasing a contain and recover Additional dedicated Shell has access to the AMOSC stockpile located at
recovery equipment Contain and Recover Guide. response will results in the vessels with Broome (and other stockpiles elsewhere in Australia).
(offshore boom and Equipment: FLNG support removal of more oil from the sea offshore boom and The effectiveness of this response strategy is affected
skimmer system) vessels surface and therefore less will skimmer systems by sea state conditions and the thickness of oil at the
AMOSC stockpile (Broome) 400 accumulate on shorelines resulting would cost in the sea surface; therefore it may only be applicable to the
m of offshore boom and skimmer in less environmental impacts to order of 10s of HFO spill scenario. Maintaining booms and skimmers
system. shoreline receptors and less waste thousands of dollars offshore is not practicable due to space limitations. The
generation. per day and is not availability of contain and recover equipment is not a
Waste storage capability considered limiting factor and other response strategies could be
Personnel: warranted given the implemented in faster timeframes (vessel-based
AMOSC/AMSA/OSRL trained availability of such dispersant) that would be more effective on HFO spills.
and experienced personnel. equipment is not a
limiting factor in the
effectiveness of this
strategy.
Shoreline Protection and Deflection
Shoreline and nearshore Processes: Browse Island Undertaking an improved Access to additional Given the logistical and safety limitations with shoreline
booming equipment Incident Management Guide shoreline protection and deflection booming equipment response in the Browse Basin, implementation of the
Equipment: AMOSC/OSRL response may reduce shoreline would cost in the response will take approximately 1 week to occur from
specialised equipment accumulation of oil resulting in less order of thousands decision being made to commence (noting that this
environmental impacts to shoreline of dollars per day decision may be made by WA DoT as the Control

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Oil Spill Response Resources Environmental gain from Alternatives ALARP assessment
Strategy increasing or improving considered
resources
Personnel: AMOSC/OSRL receptors and less waste and is not Agency). Pre-positioning of booms may result in
trained and experienced generation. considered potential damage to sensitive locations and is not
personnel. However, shorelines in the Browse warranted given the considered ALARP. Improving on this response is not
Basin are difficult to access due to availability of such considered to provide an environmental gain.
their remoteness and safety risks equipment is not a
and may not result in an overall limiting factor in the
environmental gain. effectiveness of this
strategy.
Shoreline Clean-up
Shoreline Clean-up Processes: Shoreline Clean-Up Shoreline assessment specialised N/A Shoreline surveys must be conducted systematically to
Assessment Assessment OMP, Browse personnel can be deployed to be a crucial component of effective decision-making.
Island Incident Management remote shorelines from Repeated surveys are needed to monitor the
Guide staging/accommodation facilities effectiveness and effects of ongoing treatment methods
Helicopter call-off contract within 5-6 days. Undertaking (i.e. changes in shoreline oiling conditions, as well as
Equipment: Staging and quicker shoreline assessment natural recovery). Improving the time for specialised
accommodation facility would be beneficial to obtain pre- personnel to access remote shorelines to make
impact results, however, assessments is not warranted and will not result in an
Personnel: AMOSC/OSRL shorelines in the Browse Basin are environmental gain. Noting that the decision to
trained and experienced difficult to access due to their commence this strategy may be made by WA DoT as
personnel. remoteness and safety risks. the Control Agency.
Earlier deployment may not result
in an overall environmental gain.
Manual and mechanical Processes: Shoreline Clean-Up Predictive oil spill modelling Costs for additional Shell has access to shoreline response kits. Given the
removal (washing, Assessment OMP, Browse indicates the largest volumes clean-up equipment logistical and safety limitations with shoreline response
flooding & flushing, Island Incident Management accumulating on shorelines is are considered to in the Browse Basin, implementation of the response
sediment reworking & Guide 1,393 m3 of condensate at the be negligible and will take approximately 1 week to occur from decision
surf washing) Equipment: AMOSC/OSRL Indonesian Boundary and 475 m3 are not considered being made to commence (noting that this decision
specialised equipment of HFO at the Buccaneer a limiting factor in may be made by WA DoT as the Control Agency).
Personnel: AMOSC/OSRL Archipelago. Depending on the the effectiveness of Large scale operations involving large numbers of
trained and experienced sensitivity of the shoreline removal this strategy. personnel and/or heavy equipment may cause adverse
personnel. of accumulated oil using heavy Constraints environmental impacts at many of these sensitive
machinery and/or large numbers primarily lie in shoreline locations and would not result in an
of personnel may result in mobilising environmental gain. Manual clean-up equipment, using
additional environmental damage. equipment and smaller teams for longer periods would be more effective

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Oil Spill Response Resources Environmental gain from Alternatives ALARP assessment
Strategy increasing or improving considered
resources
Access by heavy machinery would personnel safely in most of the shoreline locations predicted to be
also be restricted at offshore rather than sourcing contacted.
islands. additional
equipment.
Oiled Wildlife Response
Oiled wildlife response Processes: WA Oiled Wildlife Given access to local OWR Any OWR will be Shell is a participating member of AMOSC with access
implementation Response Plan (WAOWRP) equipment and personnel undertaken in to Mutual aid arrangements. AMSA MoU and OSRL
Equipment: AMOSC OWR (AMOSC) through existing consultation with contracts, enabling access to national and international
containers (2) and box kits. arrangements the response the relevant oiled wildlife expertise. The closest OWR container is
NatPlan OWR containers (4), capability cannot be improved to agencies e.g. WA located in Fremantle and can be mobilised to Broome
OSRL OWR equipment. result in an environmental gain DBCA and WA within 30 hours by vessel. Additional containers and
Personnel: AMOSC/OSRL unless an OWR kit is maintained DoT. Such box kits are available from other locations within
trained and experienced national offshore. consultation is more Australia (including Broome for the closest box kit).
and international OWR likely to be a time Maintaining a dedicated OWR kit offshore is not
personnel. limiting factor than considered to be reasonable given the low likelihood of
accessing additional needing to implement an OWR and the requirement for
OWR resources. trained OWR personnel.
Waste Management
Waste management Processes: Oil Spill Waste There are no limitations to obtaining Costs for additional Predictive oil spill modelling indicates the largest
Management Plan Template. the required waste storage capacity waste management volumes accumulating on Australian shorelines is 475
Equipment: Assorted waste for this EP and no environmental resources are m3 of HFO at the Buccaneer Archipelago. Using a
receptacles and trucks from benefit obtained by accessing considered to be bulking factor of 10, potentially 4,750 m3 of waste could
waste contractor with additional additional waste storage capacity. negligible. be generated during a shoreline clean-up response.
stocks from sub-contractors Decanting from contain and recover operations will also
located in Darwin, Broome generate waste for disposal. Typically, this oily liquid
and/or Dampier. waste would be held in the inboard storage tanks of the
635 m3 capacity of offshore support vessels and disposed of at an onshore facility.
storage in Darwin. Based on Shell’s waste contractor capability the
Personnel: Waste contractor available resources are considered to be suitable for the
personnel (Rusca Brothers). worst-case spill scenario.

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9.14.2 Aspect Context

This section describes any new or unique environmental impacts or risks presented by
implementation of the emergency events response strategies included in the OPEP
(HSE_PRE_013075) which may be enacted to respond to hydrocarbon and chemical
spills as described in Section 9.13. Where impacts and risks are already adequately
addressed in the preceding sections of this EP, as indicated in Table 9-87, they are not
discussed further in this section.
Typically environmental aspects, impacts and risks that arise from conducting the
emergency response activities are similar to those already described in Section 9.3 to
9.12. for the planned and unplanned activities, particularly for vessel-based operations.
Where additional impacts or risks exist for the identified aspects, these are described in
the following subsection. Table 9-87 summarises the aspects generated by
implementing the spill response activities and identifies any that are new or unique
aspects for further assessment.

Table 9-87: Spill response strategies and associated environmental aspects identified for
each including those that are considered new or unique

Aspects Generated

Planned Chemical Discharge1

Greenhouse Gas Emissions

Discharge of Liquid Wastes
Introduced Marine Pests

Atmospheric Emissions
Disturbance to Ground1
Disturbance to Seabed

Waste Management

Emergency Events
Physical Presence

Noise Generated
Lighting2

Source Control
          
(including SSDI)3
Monitor and Evaluate        
Natural Recovery
Response Activities

Chemical Dispersant
        
(Surface)
Contain and Recover         
Protect and Deflect         
Shoreline Clean-up      
Oiled Wildlife
       
Response
Scientific/ Oil Spill
       
Monitoring
Notes:
 - The aspects and associated impacts and risks are already adequately addressed in the EP Sections 9.3-
9.12.
 - There is an aspect of the response activity that may produce a new or unique impact/risk not already
addressed in the EP.

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1. New or different aspect not previously described in the EP

2. Due to daylight operations only for typical vessel-based activities (excluding source control), lighting impacts
for stationary, non-operating vessels at sea during night will not present a credible impact to sensitive receptors.
3. As described further in the OPEP, source control activities to respond to a LoWC emergency event may include
drilling a relief well. All source control activities will be managed in accordance with the accepted OPEP, Safety
Case and WOMP.

9.14.2.1.Subsea (Source Control) and Surface Dispersant Application

Dispersants are applied to hydrocarbon spills to enhance the breakdown of
hydrocarbon droplets and enhance dispersion into the water column to:
• Break up floating oil and reduce floating oil concentrations, thereby reducing the
exposure of seabirds and surfacing marine fauna to hydrocarbons
• Reduces the size of the entrapped oil droplets further aiding dispersion and enhancing
biodegradation.
Additionally, source control is the primary response strategy for the well loss of
containment scenario and is aimed at stopping the flow of well fluids to the
environment. Subsea Dispersant Injection (SSDI) may be required as part of the overall
source control strategy to ensure conditions are safe for responders (i.e. minimise gas
cloud concentration and extent) to enable relief well drilling.
9.14.2.2 Contain and Recover - Decanting Operations
Application of the Contain and Recover strategy is significantly limited by weather,
logistics, and requires substantial temporary waste storage for recovered
hydrocarbons. Recovered hydrocarbons will inevitably contain a large proportion of
water in addition to recovered oil that may need to be decanted back to the sea to
optimise the recovered oil fraction. Refer to the OPEP for further details.
9.14.2.3 Shoreline Clean-up and Protect and Deflect – Disturbance to Ground
Conducting shoreline protection and clean-up involves moving personnel and
equipment, which includes the environmental aspect of ground disturbance. The
objective of shoreline clean-up is to apply clean-up techniques that are appropriate to
the shoreline type to remove as much oil as possible where there is a net
environmental benefit in doing so. Various techniques may be used alone or in
combination to clean up oiled shorelines, including Shoreline Clean-up Assessment
Technique (SCAT), natural recovery, absorbents, sediment reworking, manual and
mechanical removal and washing, flooding, and flushing. Considerations for selecting
and implementing shoreline clean-up techniques are included in the OPEP.
The deployment of booms to protect sensitive shoreline receptors, typically pre-
emptively, introduces the potential for ground disturbance or damage to nearshore
habitats such as intertidal reefs, mangroves, seagrasses and macroalgal communities
that are present at Browse Island and other offshore islands/shorelines.

9.14.3 Description and Evaluation of Impacts

Subsea and Surface Dispersant Application – Planned Chemical Discharges
Physical Environment
Water Quality
Environmental effects associated with dispersant application include a temporary
reduction in water quality and exposure of marine biota to dispersant chemical’s

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inherent ecotoxicity, biodegradability and bioaccumulation properties. The level of

toxicity varies amongst the different dispersant types and can result in increased in-
water concentrations of the toxic components of hydrocarbons. Dispersant combined
with dispersed oil can be acutely toxic in the water column at specific concentration
thresholds, and is noted for its toxicity to habitats such as corals, seagrass, and
macroalgae.
Biological Environment
Benthic Communities
Environmental effects associated with dispersant application include an increase in the
mass of entrained hydrocarbons with smaller droplet sizes affecting larger areas and
being bioavailable for ingestion by some oceanic and benthic organisms (e.g. fish,
plankton, benthic invertebrates). The effects of entrained hydrocarbons on sensitive
environmental receptors are discussed in Section 9.13.4.
The extent of these impacts will also depend on the chemical dispersant type and dose
rates, and external conditions (time of the year, weather and sea conditions, proximity
of sensitive receptors and their life stage, etc.). These impacts will provide another
consideration into the decision process on strategy selection (SIMA) and timing on a
case-by-case basis at the time of the incident as described in the OPEP.
Sensitive reef communities are located within the Browse Basin, with the closest being
around Browse Island, Echuca and Heywood Shoals and Ashmore and Cartier Islands,
while seagrass meadows are located in some of these areas also. If applied
appropriately, dispersants can provide a net environmental benefit by limiting exposure
of an oil spill to high environmental value sensitive receptors. Elevated concentrations
of dispersant are generally localised and of short duration, with dilution and dissipation
being relatively rapid after application. Therefore, residual impacts from the use of
dispersants are expected to be low in nature and scale when assessed in isolation
compared to the impact of the spill without dispersant application, and ranked as minor
impact consequence (Magnitude -2, Sensitivity M).
Decanting Operations/Contain and Recover – Discharge of Liquid Wastes
Physical Environment
Water Quality
In order to optimise recovery of floating hydrocarbon removed from the sea surface
during Contain and Recover operations, it may be required to decant some of the oily
water from temporary storage back into the ocean which may result in dissolved and
entrained hydrocarbons being released back into the marine environment. This is not
expected to lead to additional environmental impacts compared to the pre-application
state of this strategy as the decanted water will be released at the spill site within
already affected boomed areas and not elsewhere. Thus, no additional adverse
environmental impacts are expected for water quality and marine biota and the residual
impact consequence is assessed as nil (Magnitude 0, Sensitivity – L).
Shoreline Clean-up and Protect and Deflect– Disturbance to Ground and Lighting
Biological Environment
Disturbance to Intertidal Habitats and Marine Fauna
Conducting shoreline clean-up activities, including moving personnel and equipment,
has the potential to cause damage to terrestrial and intertidal habitats, with subsequent
impacts to dune/beach structure, flora such as mangroves and fauna such as turtles

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and birds (including nests). Invasive or frequent clean-up can also involve physical
removal of substrates that could adversely impact habitats, fauna and alter coastal
geomorphology and hydrodynamics. The impacts associated with undertaking
shoreline clean-up may be more than if the product was left in place and remediated
through natural processes (Natural Recovery). Leaving the product in place is a very
common response option if continual human and vessel/vehicle traffic has the potential
to generate greater impacts than the product itself. The optimal suite of response
strategies will be determined through the SIMA process described in the OPEP.
The deployment of booms to protect shorelines and intertidal environments could
potentially cause physical damage to coral reefs/intertidal ecosystems through the
movement of the booms and/or anchors. A review of shoreline and shallow water
habitats, and bathymetry, and the establishment of demarcated areas for access and
anchoring will reduce impacts to nearshore environments.
Shoreline clean-up and protect/deflect activities will be managed to minimise impacts
on turtles (including hatchlings) and birds through minimising disturbance to nesting,
and feeding sites. Responder transfer to shore would be on small boats or helicopters.
Responders would be accommodated on nearby medium sized vessels or facilities
such as Prelude (if available). An assessment of appropriate equipment and personnel
numbers required to reduce habitat damage, along with the establishment of access
routes/demarcation zones, and operational restrictions on equipment and personnel
movements will limit sensitive habitat damage and damage to important fauna areas.
The establishment of temporary camp areas will be done in consultation with DoT,
DBCA and a Heritage Advisor if access is sought to culturally significant areas.
Given the controls in place and the short-term and localised incidental environmental
effects from shoreline clean-up activities, there would only be minor residual impact
consequences presented by personnel and equipment undertaking shoreline clean-up
activities (Magnitude -2, Sensitivity – M).
Lighting
Shoreline response activities may require use of lighting which can cause
disorientation, disruption to nesting and breeding behaviours in seabirds, shorebirds
and turtles.
Shoreline clean-up and protect/deflect activities will be managed to minimise impacts
on turtles (including hatchlings) and birds through minimising disturbance to nesting,
and feeding sites. An assessment of the need to conduct night-time operations in
sensitive areas will be made and operational restrictions established. Due to the
remote location of potentially impacted shorelines, conduct of response operations with
smaller teams to reduce ecological impacts (Refer to Section 12.3 of OPEP) and the
safety implications associated with dangerous marine fauna (e.g. saltwater crocodiles),
it is unlikely that operations will be conducted at night.
Given the controls in place and the short-term and localised incidental environmental
effects from shoreline clean-up activities, there would only be minor residual impact
consequences presented by personnel and equipment undertaking shoreline clean-up
activities (Magnitude -2, Sensitivity – M).

9.14.4 Impact Assessment Summary

Table 9-88 lists the highest residual impact consequence rankings of the relevant
environmental receptor groups.

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Table 9-88: Spill Response Strategies Evaluation of Residual Impacts

Environmental Receptor

Consequence
Sensitivity
Magnitude

Residual
Impact
Physical Environment – water quality -2 M Minor
Biological Environment – benthic
communities, intertidal habitats and -2 M Minor
marine fauna
Socio-economic and Cultural
N/A N/A N/A
Environment1

1- Potential impacts to socio-economic and cultural environment receptors are not predicted to
exceed those presented in Section 9.13 and are therefore not repeated in this section.

9.14.5 ALARP Assessment and Environmental Performance

Standards
An ALARP assessment of oil spill response capability is presented in Table 9-86. A
description of controls, EPSs and MC for each oil spill response strategy are presented
in the OPEP.

9.14.6 Acceptability of Impacts

Table 9-89 Acceptability of Impacts – Oil Spill Response Strategies
Receptor Receptor Acceptable Are the Acceptability Assessment
Category Sub- Level of Impact Impacts of
category an
Acceptable
Level?
Physical Water Limited Yes Spills from decanting and the application of
Environment quality environmental dispersant may result in a temporary
impact to water reduction in water quality. The level of
quality and toxicity varies amongst the different
quality is dispersant types and can result in
maintained so increased in-water concentrations of the
that biodiversity, toxic components of hydrocarbons.
ecological Dispersant combined with dispersed oil can
integrity, social be acutely toxic in the water column.
amenity and Dispersant application has a limited
human health window of opportunity, as the ability for the
values are dispersants to break up the hydrocarbons
protected. typically decreases as the product
weathers therefore surface application
would only be considered as a secondary
response option for an HFO spill in
conjunction with the operational SIMA,
Shell Surface Dispersant Application Guide
and the necessary regulatory approvals.
Residual impacts from the use of
dispersants are expected to be low in
nature and scale when assessed in
isolation compared to the impact of the spill
without dispersant application.

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Biological Benthic Limited Yes Increased in-water concentrations of toxic

Environment communities environmental components of hydrocarbons due to
impact which dispersant application may potentially
directly impacts contact submerged receptors such as
bare sediment corals, seagrass and macroalgae.
benthic habitats
outside of the Damage from protect and deflection
Operational equipment such as booms and anchors
Area as a result has a potential to damage intertidal
of the petroleum habitats.
activities which The optimal suite of response strategies
adversely will be determined through the operational
effects biological SIMA.
diversity or
ecological
integrity.

Threatened No significant Yes Moving personnel and equipment

and impacts to listed associated with shoreline clean-up
Migratory Threatened activities has the potential to cause ground
Species (Endangered disturbance or lighting impacts which may
and Vulnerable) affect listed Threatened or Migratory MNES
or Migratory fauna populations fauna such as nesting
MNES fauna turtles and birds (including nests). The
populations. impacts associated with undertaking
Management of shoreline clean-up may be more than if the
aspects of the product was left in place and remediated
project must be through natural processes (Natural
aligned to Recovery). Leaving the product in place is
conservation a very common response option if
advice, recovery continual human and vessel/vehicle traffic
plans and threat has the potential to generate greater
abatement impacts than the product itself. The optimal
plans, including suite of response strategies will be
for bird and determined through the operational SIMA
marine turtle and in consultation with relevant agencies
species. such as WA DBCA and WA DoT.

WA Limited Yes Damage from protect and deflection

mainland environmental equipment such as booms and anchors
coastline impacts to has a potential to damage nearshore
mainland habitats along the WA coastline. The
coastline. optimal suite of response strategies will be
determined through the operational SIMA
and in consultation with the relevant
agencies such as WA DoT.
Socio- Fisheries No interference Yes Shell will implement industry standard
economic with fishing to a controls to manage impacts from the
Environment greater extent implementation of oil spill response
than is strategies required due to unplanned
necessary for hydrocarbon spills. An operational SIMA
the exercise of will be developed by the IMT using real-
right conferred time monitoring and evaluation data to
by the titles select the optimal suite of response
granted to carry strategies.
out petroleum
activities.
Tourism & No negative Yes
recreation impacts to
nature-based
tourism
resources

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resulting in
demonstrated
loss of income.

New and/or unique environmental impacts associated with implementation of the

possible spill response strategies are considered to be acceptable where they present
a net environmental benefit compared to the ‘do nothing’ option as determined and
documented through the SIMA process as described in the OPEP.
Assessment of these impacts from the spill response strategies discussed above
determined the residual ranking of minor or lower (Table 9-88). The acceptability of
these impacts has been considered in the context of:
Principles of ESD
The response option impacts described above are consistent with the principles of ESD
based on the following points:
• The health, diversity and productivity of the marine environment will be optimised for
future generations through minimising the impact of any large scale spills through
implementation of the accepted OPEP and associated response strategies;
• The precautionary principle has been applied, and studies undertaken where knowledge
gaps were identified. This knowledge has been applied during the evaluation of
environmental impacts
• With the prevention and mitigation controls in place, the conservation of biological
diversity and ecological integrity shall be optimised following a large scale spill.

Relevant Requirements
Management of the impacts associated with spill response strategy implementation are
consistent with relevant legislative requirements, including:
• The NOPSEMA accepted OPEP (HSE_PRE_013075).

Matters of National Environmental Significance

Threatened and Migratory Species
Alignment with the relevant management plans, recovery plans and conservation
advice for threatened and migratory fauna will be addressed on a case-by-case basis
through the SIMA process when selecting appropriate spill response strategies
(Reference is made to Table 7-6 for the list of potentially applicable plans and advisory
documents). These plans and advisory documents will assist with determining
protection priorities once the nature, scale and trajectory of the spill is understood post
event.
Commonwealth Marine Environment
The new and/or unique environmental impacts presented by dispersant application,
decanting and/or shoreline clean-up on the Commonwealth marine environment when
assessed in isolation from the spill event itself will not credibly exceed any of the
significant impact criteria provided in Table 8-1.
External Context
There have been no objections or claims raised by Relevant Persons to date around
the dispersant application, decanting or shoreline clean-up aspect. Shell’s ongoing

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consultation program will consider statements and claims made by stakeholders when
undertaking further assessment of the risks.
Internal Context
Shell has also considered the internal context, including Shell’s environmental policy
and ESHIA requirements. The EPOs, and the controls which will be implemented, are
consistent with the outcomes from stakeholder consultation for the Prelude FLNG
facility and Shell’s internal requirements.
Acceptability Summary
As outlined above, the acceptability of the associated impacts have been considered in
the context of:
• The established acceptability criteria
• ESD
• Relevant requirements
• MNES
• External context (i.e. stakeholder claims)
• Internal context (i.e. Shell requirements).
The residual impacts have been assessed as minor which Shell considers to be
acceptable if they meet legislative and Shell requirements. The discussion above
demonstrates that these requirements have been met in relation to the new and/or
unique impacts associated with implementation of the identified spill response
strategies. Based on the points discussed above, Shell considers the residual impacts
to be ALARP and acceptable.

9.14.7 Environment Performance Outcome

Environment Performance Outcome Measurement Criteria

Spill response strategies shall be selected and OPEP implementation records and SIMA records
implemented to minimise the overall
environmental impacts from a spill and the
associated implementation of the response
strategies themselves.

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10.0 Environmental Plan Implementation Strategy

The OPGGS (E) Regulations require an Implementation Strategy to be incorporated
into the EP that includes:
• Measures, systems and practices to ensure that environmental risks continue to be
identified and reduced to a level that is ALARP, mitigating measures are effective, and
EPOs and standards are met
• Chain of Command
• Measures to ensure workers are aware of their responsibilities
• Monitoring and management
• Records and reporting
• OPEP provided as a separate document together with this EP submission
• Consultation.

10.1 Management Systems

The Shell HSSE & SP-MS provides a structured and documented framework for the
effective management of HSSE & SP risks and demonstrates how the requirements of
the Shell Group HSSE & SP Control Framework are implemented throughout Shell.
The Shell HSSE & SP-MS Manual consists of the following sections:
• Leadership & Commitment
• Policy & Objectives
• Organisation, Responsibility & Resources, Standard & Documents
• Risk Management
• Planning & Procedures
• Implementation, Monitoring & Reporting
• Assurance
• Management Review

The HSSE & SP-MS is subject to a continuous improvement ‘plan, do, check, review’
loop, with eight components as outlined in Table 10-1. There are numerous, specific
ongoing (typically annual) assurance activities against each of the eight components in
this HSSE & SP-MS Manual as detailed below. The audit and review function of the
HSSE-MS seeks to ensure that the system is being implemented, is effective and to
identify areas for improvement. Examples of elements that demonstrate continuous
improvement are highlighted under each section.

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Table 10-1: HSSE & SP-MS Elements Implementation and Improvement

Management System Element Implementation and Improvement

Leadership and Commitment Seek ongoing feedback on how others perceive HSSE
Creating and sustaining a culture that drives & SP leadership (performance reviews, HSE Culture
Shell’s commitment of no harm to people or Survey (Shell People Survey), 360 feedback)
the environment
Policy and Objectives Set annual HSSE & SP targets to drive continuous
Supporting the implementation of Shell HSSE performance
& SP Commitment and policy Annually Review and approve HSSE & SP objectives
Organization, Responsibilities and Resources When there are changes in the Business or
Establishing and maintaining an organization organization, identify the positions that require
that enables the compliance with the HSSE & Competence assurance.
SP Control Framework HSSE & SP Critical Position Register, Shell People
Competency Profiles
Risk Management Ongoing review of Hazards and Risks. Regular review
Identifying the HSSE & SP hazards and of Risk Registers
establishing the controls to reduce the risks to
ALARP
Planning and Procedures Establish and maintain a programme of testing of
To integrate the requirements of the HSSE & Emergency Response plans and procedures at least
SP Control Framework into business plan and once a year or more frequently based on the level of
procedures: Emergency & Crisis Response, risk. Shell Australia ERP, Records of ER drills,
Spill Preparedness and Response, MOC, exercises and AARs.
PTW
Implementation, Monitoring and Reporting Report all Incidents, including Near Misses, to the
Implement the HSSE & SP requirements Supervisor of the work activity. Learn from Significant
embedded in plans and procedures and take Incidents and High Potential Incidents through
corrective action when necessary communication and implementation of required
actions.
Assurance Establish, maintain and execute HSSE & SP Self-
Providing assurance that the HSSE &SP Assessments in support of the Business HSSE & SP
Control Framework requirements are Assurance Plan, self-assessment, CF Gap Analysis,
implemented and effective HSSE & SP Management Review.
• Management Review (documents demonstrating
how Shell Australia reviews the effectiveness,
adequacy and fitness for purpose of the HSSE &
SP Management System and take action to
improve)
• Review the HSSE & SP Management System
and its individual elements at least once a year
and document the results.

Management Review Assess the Effectiveness and Adequacy of the

Reviewing the effectiveness, adequacy and management system in delivering the policy and
fitness for purpose of the HSSE & SP MS and Objectives and in driving continual improvement.
taking actions for improvement

Shell’s HSSE & SP-MS covers all operations within its business, including that of the
Prelude FLNG Facility and all assets/operations (e.g. to Prelude and future operations).
Management of HSSE on the Prelude FLNG facility is through the implementation of
the Shell HSSE MS, supplemented by facility/asset specific HSSE systems/procedures
(e.g. Prelude Permit to Work system and associated procedures such as Confined
Space Entry, Isolations, etc.).

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Shell implements specific pre- and post-contract award processes and activities aimed
at ensuring that contracts consistently and effectively cover the management of HSSE
& SP risks and deliver effective management of HSSE & SP risks for contracted
activities.
Contractor HSSE & SP Management is governed by the Shell HSSE & SP Control
Framework. As a minimum, all relevant field active contractors’ HSSE & SP-MS will be
assessed to ensure they meet materially equivalent outcomes to Shell’s HSSE & SP-
MS.
For the activities that occur offshore but not onboard of the Prelude FLNG facility (e.g.
vessel activities within the PSZ), Vessel Contractor predominantly use their own
vessel/facility HSSE-MSs to manage work scope onboard their vessel.

10.1.1 Environment Critical Element Management

Environmentally Critical Element (ECE) is an item of equipment or structure whose
failure could lead to:
1. the release of a major environmental hazard or whose purpose is to prevent or limit the
consequences of a major environmental hazard (RAM Red or Yellow 5A/5B
Environmental risks); or
2. environmental regulatory non-compliance as part of implementing the controls to
manage environmental hazards to ALARP and Acceptable levels.
Environmentally Critical Elements are mostly equipment and are frequently referred to
as Hardware Barriers.
Identification of ECEs, and assurance of their implementation effectiveness is an
important element of ensuring that barriers will function as required. Figure 10-1
illustrates the overall process of identification of ECEs and integration with Safety
Critical Elements (SCEs), the Business Management System (BMS) and the
competency system. Figure 2 illustrates the relationship between ECEs and SCEs.

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Figure 10-1: ECE Identification Process

Figure 10-2: Illustration of the relationship between SCEs and ECEs

For Prelude FLNG, Major Environmental Hazards (RAM Red or Yellow 5a/b) are also
associated with some Major Accident Events (MAE) in the Safety Case. Some Bowties
within the Safety Case are also appropriate for managing the Major Environmental
Hazards. Those Bowties were developed to illustrate the threats that can lead to the
realisation of an MAE (incl. those associated with Major Environmental Hazards) and
the barriers that can prevent this occurring or mitigate the consequences. Some ECEs
are also SCEs.
Deviation

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Deviations are able to occur through following the ECE management guidance
(OPS_PRE_15791). This is an approved non-compliance of the mandatory
requirements of a procedure, standard or specification. This is applied to assurance
and environmentally critical corrective and preventative maintenance that will not be or
has not been carried out by the due date.
Overrides are able to occur following the ECE management guidance. An override is
an interruption to the normal operation of an environmentally critical element that
prevents it from performing the desired action.

10.1.2 Contractor Management

Contractors and their sub-contractors carry out a number of activities on behalf of
Shell. Effective management of environment, integrity, health and safety risks in
contracts involves setting clear expectations and managing these risks throughout the
contract lifecycle.
Shell implements specific processes and activities aimed at ensuring that contracts
consistently and effectively cover the management of HSSE & SP risks for the
contracted activities. These processes are detailed in the Prelude HSSE & SP
Contractor Management Strategy Manual. The contractor management processes
implemented for Prelude FLNG are consistent with the requirements of the Shell HSSE
& SP Control Framework Contractor HSSE Management Manual.
Key aspects of the Contractor HSSE Management are:
Pre-contract Award Activities
• Appointing a competent contract owner and contract holder for each contract.
• Determine the Contract HSSE & SP risk, by assessing the risk associated with the
contracted activities.
• Determine the contract mode.
• For a high contract HSSE Risk, the contractor is to develop and provide a Contract
HSSE Plan.
• Assess whether the Contractor has the capability and resources to manage the risks
associated with the contracted activities.
• Before contract award, confirming that the Contractor meets requirements. Focus on
closing gaps in draft contract HSSE & SP Plan submitted by Contractor.
• Define the level of Company monitoring based on the capability of the Contractor, the
contract HSSE & SP risk and the contract mode.

Post-contract Award Activities

• Require the Contractor to demonstrate that Contractor personnel responsible for
managing the HSSE Risks of the contracted activity have knowledge of the HSSE
requirements of the contract and any associated Contract HSSE Plan related to their
role.
• Require the Contractor to demonstrate that all Contractor personnel will be given an
induction on the HSSE risks of the contracted activities including the controls to manage
those Risks specified in the contract and any associated Contract HSSE Plan.

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• Verify that the HSSE requirements of the contract and any associated Contract HSSE
Plan are being implemented and are effective at managing the HSSE Risk of the
contract. Where necessary implement actions for improvement.
• Regularly assess the HSSE performance of the Contractor, including its management of
Subcontractors.

10.1.3 Contractor Competency Requirements and Assurance

The contractor is responsible for ensuring that all their personnel have the appropriate
level of competence required to safely and effectively carry out the work. The
contractor is also responsible for the development and implementation of a
competence assurance plan. The contract holder is responsible for ensuring that the
contractor’s competence assurance system is reviewed, robust and meets the Shell
requirements.
In addition to trade competencies and qualification requirements, the minimum
competence requirements for key contractors working on Prelude are based on the
required contractor work scope and are developed in consultation between Shell and
the contractor. The minimum requirements for a contractor going offshore on the
Prelude FLNG facility include the following:
• Facility Induction (such as Life Saving Rules, Emergency Response and Muster
procedures, Incident Reporting, Waste Management, Oil Spill Awareness)
• Role-specific training such as Permit to Work, operating procedures of specific process
units

10.1.4 Asset Integrity – Process Safety Management System (AI-

PSM)
Shell AI-PSM focus areas are as follows:
Design Integrity:
• The aim is we design and build our assets so that risks are As Low As Reasonably
Practicable (ALARP).
Technical Integrity:
• Barriers are put in place to manage Major Accident Events (MAEs). Technical Integrity
ensures that we maintain the provided hardware barriers (from Design Integrity) to keep
them effective. Section 11.1.6 describes the maintenance processes of the hardware
barriers.
Operating Integrity
• Together with design and technical integrity, one key aspect of assuring our assets are
safe is working within the operational barriers. Operational Integrity processes ensure
that the facility is being operated within its design.
Leadership Integrity
• Leadership is the key enabler to ensure that we have assets that are safe to operate.
Each leader plays an important role in safeguarding against process safety and
environmental incidents and must demonstrate visible and felt leadership in the field.

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Figure 10-3: Shell AI-PSM Focus Areas

10.1.5 Asset Management System

Shell is implementing the global Shell Asset Management System (AMS) framework as
a single, control framework for managing Producing Assets in Shell. Prelude is
transitioning to the AMS and is targeting full compliance by the end of 2021.
The AMS framework describes a set of processes needed to organise asset
management capabilities, ensuring that activities are performed consistently in a
joined-up manner and systematically improved to deliver excellent sustainable
business outcomes.
It includes mandatory elements (through Standards and Manuals) and non-mandatory
elements (through Recommended Practices), and should be used in conjunction with
other Shell Control Framework requirements; for example the HSSE & SP Control
Framework.
The Asset Manager is accountable for ensuring adherence to the AMS. The AMS
standard provides all the tools and processes which help an asset get to at least the
minimum requirements comprising four major sections:
1. Leadership, Commitment & Accountability
2. Requirements Processes & Guides
3. Organisational Capability
4. Learning Loops

10.1.6 Design and Operational Envelope

Prelude FLNG facility has been designed and built to ensure that the risks associated
with process safety and environmental events have been managed to ALARP. This is
part of the “Design Integrity” focus areas of the AI-PSM.
Design limits define the boundary of the design envelope for each piece of equipment
and if violated could potentially lead to a loss of containment. These limits (such as
pressure, temperature and level) have been set using industry and company standards
and assured via various process safety reviews (such as HAZOP and Desktop Safety
reviews).

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Another key aspect of assuring the facility is working safely within the operational
envelope. This is part of the “Operating Integrity” focus area of the AI-PSM. Operating
envelope identifies the integrity and capacity constraints of a system, which is within
the boundary of the design envelope. Limits to operating envelope (such as process
trips and set points) are set in conjunction with process engineering Technical Authority
and Process Automation and Control (PACO) and documented in the alarms variable
table, taking account of equipment constraints and operator response time.

10.1.7 Maintenance & Integrity Execution

The management of maintenance and integrity in Prelude is in accordance with the
Shell Group Maintenance & Integrity Execution processes. Implementation and
embedding the processes ensures that Prelude is in a position to operate the FLNG
facility in a safe and environmentally-responsible manner and realize the benefits of a
proven maintenance execution process. Excellence in maintenance execution means
‘the right job, by the right person at the right time’; i.e. jobs that are approved, scoped,
performed with the right competency and attitude, scheduled to be performed at a time
that reflects the needs and risk of the business.
The proactive and visible management of critical equipment is a fundamental aspect of
Technical Integrity Management. The execution of Integrity Assurance (IA) activities
(the identification, prioritisation and subsequent execution of Integrity related corrective
and preventative work) are executed through a common maintenance work
management process. It is key that assurance/ IA tasks within the planned
maintenance routines are identifiable and can be linked to the risk barriers; making it
transparent that all risk barriers are in place and effective. The key IA activities within
the maintenance process are summarized below and in Figure 10-4.
• Technical Integrity Data capture
o Critical equipment including related equipment necessary for environmental
protection are identified and then logged into the Shell MMS. Operate phase
Performance Standards for this equipment are documented.
o Integrity Assurance tasks against the relevant are logged into SAP.
• Training and coaching for managing & executing IA tasks
• Implementation of the process
o Making sure all Preventive Maintenance work is executed to the correct standard
and within the prescribed timeline.
o Raising the need to attend to a breakdown and fixing it
o Recording of history of work executed in the asset
o Making sure the right work is being performed at the right time, with the right
people, right tools, right access, etc. and that it is done safely.
o Embed the use of Total Reliability measures
o Activation and use of Facility Status Report (FSR) for Deviation Management and
Visualisation. Further details on FSR are in Section 11.1.6.1 Key MIE Tools.

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Key
Maintenance Execution

Integrity Assurance

Key
HSE/Safety Establish Basis
Establish Basis Maintenance Execution
Case &
CMMS Build HSE Mgt Risk & Integrity Assurance
System
Design Safety Case Identify Reliability
HEMP Bowties Safety Critical Build Asset ManagementTag and
Design PS Element (SCE) DefineRegister (tags) Equipment Register
SCE Ident. Guidance Doc
Performance
Define Ops Standards (PS)
PML Performance & Acceptance
Global Operate PS Standards Criteria
Planned
Identify Maintenance Control
Assign
Design PS Safety Critical
Acceptance Spares and Bill Optimisation Deviations
ESPIR
Vendor Equipment Data Element (SCE)
Criteria Of Materials
Structured PS
& Acceptance
Criteria
Deviation
Measure Asset Develop Develop
Preventive Preventive Preventive
Localised PML Control
Maintenance RegisterMaintenance Maintenance
IPF
Assurance Assurance Tasks Reliability Tasks
Set up RBI

PM Plan
Set up Preventive Maintenance
Visualise the
Status

Work the Process Prepare

Preventive
Work
Schedule
Execute Close Out Analyse
Follow-on Work
activity ident.

Results Visibility
Identify & Prepare Assurance Task
Recording of
Prioritise Shop Paper
Corrective Corrective (QM) Results
Work Work
Auto-follow on request

Figure 10-4: Maintenance & Integrity Execution Processes

11.1.6.1 Key MIE Tools

Table 10-2 lists the key tools currently used on Prelude to manage SCE hardware
barriers. These tools may change over time as more effective options become
available. Tools specific to SCE groups are discussed in the respective Integrity
Management Plans.

Table 10-2: Technical Integrity management Tools

Tool Name Function

CMMS Computerised Maintenance Contains Prelude Asset Register with SCE identified
Management System Maintenance work planning, scheduling and
execution management
Documentation of completion of maintenance work
Business Warehouse function for maintenance KPI
reporting and analysis
Quality Module for analysis of maintenance work
Integrated with other business systems for
purchasing, materials management, finance and
logistics
CIMS Corrosion and Inspection Master source of inspection schedules and records
Management System for pressure equipment and structures
Interfaces with CMMS for scheduling and status of
inspection activities (as PM work orders)
IMSA Integrity Management System Integrity management software for pipelines and
Application underwater assets (apart from wells).
FSR Facility Status Report Status of Preventive Maintenance and Corrective
Maintenance work orders and deviations

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eWIMS Wells Integrity Management Management of wells specific integrity tasks.

System Interfaces with CMMS for scheduling and status of
tasks (as CM or PM work orders)

10.1.8 Permit to Work (PTW)

The Permit to Work (PTW) process is used to control and approve work on the Prelude
FLNG facility and within the Prelude Safety Zones. It ensures that adequate controls
and measures are in place to safeguard people, asset and environment from work
activity hazards. Details of the PTW process is described in the Permit to Work Manual
(HSE_PRE_004404) and an electronic PTW system is used. There is a high level
redundancy built into the electronic PTW tool.
A permit is required for activities that have the potential to adversely affect personnel’s
safety/health, cause damage to asset, the environment and reputation. Most activities
on Prelude FLNG require a permit; examples include hot work, breaking containment
and confined space entry. However, there are standard operational and marine
operations activities that do not require permits and are managed through approved
procedures; execution of these activities is allowed only after safety and environmental
precautions have been put in place.
All permitted activities on Prelude are categorised based on their risk level: into low-
low, low, medium or high risk. The level of risk assessment, review and approval are
proportionate to the risk of the activity.

10.1.9 Management of Change (MOC)

The MOC process for Prelude FLNG is described in the Shell MoC Manual. The MoC
process is designed to “provide assurance that, when changes are introduced, new
risks are not knowingly incurred, or the prevailing risk profile is not adversely changed
without appropriate mitigation”.
The scope covered by this manual includes:
• Process Changes (Hardware, Process Control, Process Conditions)
• Procedural Changes that affect HSSE Critical Content
• Organisational Changes (Shell and Contractor) impacting HSSE Critical Roles.
The application of this scope includes:
• Permanent Change
• Temporary Change
• Emergency Change.
The MoC Manual is supported by specific procedures, templates and checklists. The
progress of change requests is monitored through an electronic MoC system.
The MoC process is built around seven simple steps forming an overarching
governance framework (Figure 10-5).

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Figure 10-5: Management of Change Process Steps

The screening process for all new changes (hardware or software) require assessment
of HSSE&SP aspects as per Management of Change (TEC_GEN_001465) this may
result in a change being flagged as possibly needing a change to the EP which require
compliance with Regulation 17 of the Environment Regulations. If a change is
considered significant as per Regulation 17 (5) or (6) and as determined by the MOC
process, then a revised or new EP will be submitted to NOPSEMA for acceptance. The
following examples or scenarios would generally be considered significant changes:
• Tie-in of new wells, reservoirs or facilities
• Major unplanned subsea repairs
• Drilling new production wells
• Major process changes which result in significant increases in environmental risks or
impacts.
The following will also trigger the review of the management of a particular
environmental impact or risk to ensure that ongoing management of impacts and risks
are at ALARP and Acceptable levels:
• Changes in regulatory requirements/standards
• Information which may suggest an increase in environmental risks or impacts to those
outlined in the EP
• Prominent new scientific studies which may ‘negatively’ change the understanding of
environmental risks and impacts
• Objections or claims raised which require changes in EP content following the process
outlined in Section 5.0.

10.1.10 Chemical Selection Process

Shell has adopted a chemical selection and approval process in accordance with
Shell’s chemical selection and approval guidelines as indicated in Shell Chemical
Management Process (HSE_GEN_007879) and Shell Global Product Stewardship
guidelines to assess chemicals than may pose environmental impact via planned
discharges.
All chemical applications are required to be screened in accordance with Shell Global
Product Stewardship guidelines (Figure 10-6).
Where chemicals may be discharged to the marine environment preference shall be
given to chemicals that are deemed environmentally acceptable (PLONOR, Gold,
Silver, D and E) with no substitution warning under the Offshore Chemical Notification
Scheme (OCNS) adopted in the United Kingdom and the Netherlands. Chemicals that

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fall within this banding require no further assessment and are deemed ALARP and
accepted.
Chemicals that do not have an OCNS ranking or fall outside of the preferential banding
(PLONOR, Gold, Silver, D and E with no substitution warning) are required to be
assessed further incorporating seeking a suitable alternative chemical of lower
environmental impact. If no alternative is technically suitable, the chemical is required
to be assessed via Shell Global Product Stewardship guidelines and ALARP
demonstration with risk reduction control measures (Figure 10-7). Approval will be
provided by the Shell Production Chemist / Product Steward Focal Point. Chemicals
that are not deemed ALARP will be not approved and an alternative product shall be
requested.
To ensure that chemicals which may pose impact to the marine environment are
managed appropriately on an ongoing basis, annual compliance checks will be made
by Shell and chemical vendors of Shell’s Chemical Programme Treatment Guide
(TEC_PRE_006805) and Chemical Risk Assessment Register operational chemical
registers. To accompany routine compliance checks, the impact of chemicals in key
discharge streams will be assessed on an ongoing basis as indicated in Adaptive
Management Framework outlined in Section 10.4.1.

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Shell Global Product

Stewardship
Guidelines
RAM Assessment

New chemical Chemical Approval

Preliminary hazard and
or Form submitted SDS screening
compliance screening
Significant chemical change with SDS

Blue and
non discharged chemicals
Environmental Discharged,
Chemical Selection Or Yellow and Red
Assessment is required
for all chemicals that
are likely to be
discharged ALARP demonstration

HSE risk and compliance

Environment risk and

compliance (for discharged)
Approval of SDS and
Apply MoC and Physical risk and compliance
Start use update
controls
documentation

Figure 10-6: Chemical Approval Process

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No

Yes

Does application impact

Is Chemical listed as:
Is chemical already existing Environmental
New chemical application PLONOR
on the approved Impact Assessment?
Or Yes Yes OCNS (Gold, Silver, D,E)
discharge list? • Change in OCNS rating
Significant chemical change No OCNS Substitution
(TEC_PRE_006805) • End of pipe
Warning
concentration
No

No

ALARP Demonstration required:

• Chemical Impact & End of Pipe
Concentration
• Ecotoxity data
• Available HQ data
• Review preliminary hazard and
compliance screening
• Investigate elimination or substitution
• Assess control measures

Not ALARP ALARP

Chemical is deemed ALARP

Chemical is not ALARP for and approved
chemical discharge and not • Update approved
approved chemical discharge list
(TEC_PRE_006805)

Start use

Figure 10-7: Environmental Chemical Impact Assessment

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10.1.11 Greenhouse Gas and Energy Management System

Various elements of the Shell management system make up the overall GHGEM
system. The AMS GHGEM is compatible and complementary with ISO-50001
international standard for Energy Management Systems, and the Shell Group HSSE &
SP Control Framework GHGEM Manual. Key processes that form GHGEM on Prelude
include:

1. Fuel and Flare Policy;

2. Leadership Commitment;
3. Annual GHG abatement workshop and process;
4. GHGEMP (including a Methane Improvement Plan);
5. OP Process; and
6. Fuel and Flare Forum

Figure 10-8: Greenhouse Gas and Energy Management Key Processes

Fuel and Flare Policy
The Fuel and Flare Policy provides that Shell Australia, as operator of Prelude FLNG,
will:
1. “In accordance with the HSSE & SP Control Framework - Greenhouse Gas and Energy
Management ensure:
a. Energy use and GHG emissions are monitored and managed for continuous
improvement.
b. The global GHG emission inventory is subject to independent assurance.
c. Installations are designed not to flare or vent hydrocarbons continuously as a
means of Disposal. Out of scope are flare pilot and purge gas.
2. Operate facilities to control Fuel, Flaring or Venting consistent with the facility design.

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a. Do not allow flaring or venting of hydrocarbons unless required for emergency,

process safety reasons, start-up or during well clean-up or well flow tests.
b. Manage changes from the design affecting fuel, flaring or venting in accordance
with the Management of Change process.
3. Set availability targets and greenhouse gas emissions targets through annual Business
Planning. Performance against these targets is reflected in the Company Scorecard
(which is set at Shell Group level).
4. Pursue opportunities to minimise planned flaring events.
a. Planned flaring events shall be minimised by using the Integrated Activity
Planning process. The GHG impacts are available inputs into the planning
process.
5. Pursue opportunities to minimize unplanned flaring events.
a. Certain scenarios are captured in the Operations Playbook
6. Monitor, evaluate and record fuel and flaring events as input into continuous
improvement initiatives.
7. Pursue opportunities to reduce fuel use to minimum thereby maximising feed gas
available for sale.
8. Minimise methane emissions through a robust and risk-based Leak Detection and
Repair program.
9. Prelude’s GHGEM Plan shall be updated annually to reflect the latest GHG forecast and
strategic management controls (e.g. abatement projects).”
Leadership Commitment

Consistent with ISO50001, leadership for GHGEM is shown and demonstrated in

various ways including:

• ensuring that the GHGEM scope and boundaries are established in GHGEM system;
• ensuring that the fuel and flare policy and GHG targets are established and are
compatible with the strategic direction of Shell;
• ensuring the integration of the GHGEM requirements into Prelude’s AMS processes;
• ensuring that action plans are approved and implemented;
• ensuring that the resources needed for the GHGEM are available;
• communicating the importance of effective energy management and of conforming to
the GHGEM requirements;
• ensuring that the GHGEM achieves its intended outcome(s);
• promoting continual improvement of energy performance and the GHGEM;
• ensuring the formation of an GHGEM management team (fuel and flare forum);
• directing and supporting persons to contribute to the effectiveness of the GHGEM
processes;
• supporting other relevant management roles to demonstrate their leadership as it
applies to their areas of responsibility;
• ensuring that processes are established and implemented to identify and address
changes affecting the GHGEM processes within the scope and boundary of the
GHGEM.

The main leadership forums where GHGEM performance against targets and GHGEM
action plans is tracked include:

• monthly forums: Prelude Asset Leadership Team, Shell Australia Country Leadership
Team, Prelude HSSE management and the Prelude fuel and flare forum;
• Annual HSSE management review at Prelude and country levels.

Annual GHG Abatement Workshop and Process

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An annual Prelude GHG abatement workshop identifies risks and opportunities which
reduce GHG emissions through abatement or efficiency gains in operating Prelude.
GHG abatement opportunities can be either operational improvements or capital
projects. The first abatement workshop for Prelude occurred in November 2020. The
workshop participants are comprised of a multidisciplinary team, which typically
includes operators and engineers from various departments of Prelude FLNG facility.
Outputs from the workshop include a list and description of abatement opportunities
identified, high level technical feasibility screening of the opportunities, the estimated
cost of such opportunities and abatement volume estimates. This first workshop in
November 2020 delivered approximately a number of GHG opportunities which will be
further screened and assessed.
All technically feasible abatement opportunities are then further screened and
assessed through a GHG abatement funnel pipeline. Where assessment has been
completed, relevant capital projects are assessed in accordance with relevant internal
processes (e.g. ORA and Manage Threats and Opportunities (MTO)) along with all
other abatement opportunities to determine the point at which GHG risks are reduced
to ALARP. Those capital projects that are subsequently screened to be in-plan are then
put into the proceeding OP cycle so that budgets and resources can be assigned
according to the priority given. Projects (including out of plan) are reviewed on an
annual basis by the Prelude asset team to see if the criteria for sanctioning a project
are met.
A high level overview of this process is outlined below.

Themes (examples) Abatement Economic and Abatement Implementation GHGi Yearly Target
Environmental Screening ALARP Criteria
• Operational Excellence • CAPEX, ease of implementation
• Energy Efficiency • Initial screening for potential • Analytical and visual and abatement potential form
• Reliability technical feasibility. Not illustrations used to determine the key basis for prioritising
• Optimisation technically feasible the point when GHG risk is implementation.
• Reduce Losses opportunities are screened reduced to ALARP. This • Prelude GHGi target (including
out. considers key factors of cost, all in-plan abatement projects)
• Potentially feasible ease of implementation and will be added to Prelude score
opportunities with CAPEX/ abatement potential. card, then to SA, then IG, then
OPEX will follow Shell • Opportunities beyond ALARP Group Score Cards1.
processes (e.g. ORA, MTO etc) will be reassessed the following • Tracked monthly by ALT & CLT
for further technical feasibility, year via master register • Annual Prelude GHG assurance
economic and abatement Process
potential assessments.
• Assessed using SA Carbon Cost

GHG Abatement Workshop Gap to Potential Screening Implement Projects

Note 1: Remuneration of senior executives linked to delivery of short-term Net Carbon Footprint targets and growth in New Energies businesses and expanding this link to
remuneration to some 16,500 staff in 2020.

Figure 10-9: Prelude GHG Abatement Opportunity Identification and screening process
Abatement projects implemented between Prelude since 2019 commissioning and
November 2020 have saved in excess of 30kt CO2-e being emitted. Abatement projects
that have been implemented on Prelude since 2019 include:
• Perform minimum turndown tests for wells and flowlines with the aim to turn down to
from 50 Mmscfd to 25Mmscfd (or lower). Minimised flaring when operating on Utility
Island mode on wet fuel gas. – 10000tpa CO2-e
• Upstream: Update Well Start-up procedure to optimise flaring by smooth transition to
HP flowline mode and placing riser chokes in CAS - 11000tpa CO2-e

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• MEG pretreatment time reduction to reduce flaring caused by restart time.- 50%
reduction in flaring during flowline pretreatment (1200t saved in total every time shut in
occurs)
• HP separator pressure control issues due to operating in Manual mode for relief control
valves – 500-1000tpd CO2-e.
Table 10-3 below outlines the nine in plan projects accepted for implementation between 2020
and 2022 which make up the OP20 abatement target for 2021 of 90kt CO2-e on a risked basis.
Future abatement workshops will consider BAT literature sources such as the IEA Methane
Abatement Options.
Table 10-3: OP20 in plan abatement projects
Project Category
Number Description

Steady &
1 Flaring Passing valves: Leaks to the flare from two identified locations.

Non Steady Well Start-up procedure to optimise flaring by smooth transition to

& Flaring high pressure flowline mode and placing riser chokes in cascade
2 operation.

Steady &
3 Flaring Two identified passing valve rectifications.

Non Steady Reduced minimum turndown for Prelude. - Perform minimum

& Flaring turndown tests for wells & flowlines with aim to turn down to from 35
Mmscfd to 25Mmscfd (or lower). Minimised flaring when operating
4 on Utility Island mode on wet fuel gas.

Non Steady
5 & Flaring Shut in wells (no flare excess - use line pack from flowlines)

Non Steady Warm End flaring optimisation opportunity - After NGL trip (Achieve
& Flaring zero flaring when NGL Column trips by operating AGRU and mole
sieve at minimum turn down flow rates from one well operation (~35
Mmscfd) and continuously provide dry fuel gas supply downstream
6 of the mercury removal unit)

Non Steady Warm End Start-up optimisation: (Maintain minimum turndown flow
& Flaring rate from one well (35 Mmscfd)
*Change the CO2 specification at the top of the absorber to be
100ppm instead of 50 ppm (during AGRU startup).
*Pressurise mole sieve and start regeneration straight away after
reach 100 ppm spec.
*Use 1+1 mole sieve mode of operation and provide dry fuel gas
from mercury removal unit once first bed regeneration is completed.
7 *Add critical alarm at required inlet )

Non Steady NGL column Start-up / Cool down optimization opportunities:

& Flaring 1- NGL column cooldown on total recycle from NGB without flaring .
This will result in eliminating ~ 3000t/d flaring for the NGL cooldown
8 & thermosyphon requirements ( ~ 2 days )

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Project Category
Number Description

Non Steady Draining requirements after shut-down

& Flaring 1- Cooling Water Heat Exchangers and Main Cryogenic Heat
Exchanger liquid draining after shut down
9 2- End flash column draining - valve opening requirements

Greenhouse Gas and Energy Management Plan

Management of GHG risk is one of the top priorities for Shell. As a result, specific
requirements are integrated into Shell’s management systems. The HSSE & SP
Control Framework requires that assets establish and implement a GHGEMP:

A key objective of the GHGEMP is to manage impacts from GHGEM to ALARP. As of

December 2020, the key objectives of the Prelude GHGEMP is to:

• Focus on GHG emissions, in particular flaring, during non-steady conditions which

includes, trips, start-ups and shutdowns
• Provide an overview of abatement projects (both in and out of plan), to reduce GHG
emissions to ALARP
• Establish GHG targets and set out GHG limits from external sources.
• Provide GHG forecasts over the life of the Prelude field.
• Demonstrate how Prelude FLNG manages GHG risk consistent with the GHGEM
control framework requirements and local regulatory framework
• Document the Methane Improvement Plan
GHG targets and forecasts set out in the current GHGEMP for 2020 includes intensity
target of 0.73tCO2-e/tHC and total CO2-e forecast of 2.8Mt. GHG metrics which will be
outlined in the next GHGEMP revision for 2021 includes intensity target of 0.6tCO2-
e/tHC, forecast total CO2-e: 2.3Mt and an abatement target of CO2-e: 90kt (risked).
These Prelude targets are rolled up into Shell Group targets which are linked to the
remuneration of senior executives for delivery of short-term Net Carbon Footprint
targets and growth in New Energies businesses and expanding this link to
remuneration to some 16,500 staff in 2020 50.
Shell Group has a target to maintain methane emissions intensity below 0.2% by 2025.
This target covers all oil and gas assets for which Shell is the operator and therefore
includes Prelude. From 2021 onwards, Prelude will have a MIP. The objective of the
Prelude MIP, which will form part of the GHGEMP, is to improve methane emissions
reporting, focusing on reducing uncertainty associated with methane emissions
quantification. This will facilitate prioritisation of methane emission sources for targeted
abatement projects.
Specific actions aimed at reducing methane emissions include:

50 Shell Sustainability Report 2019

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1) annual abatement project identification and assessment process (first workshop

occurred in November 2020).
2) GHGEMP with emissions intensity and abatement targets linked to asset
performance scorecard, required annual deliverable.
3) Asset QPA conducted and assessment of progress of MIP deliverables and
abatement projects is tracked quarterly.
4) Fugitive (general leaks) methane sources are being addressed via
comprehensive LDAR program.

Operating Plan
The OP process is a key deliverable of the Prelude asset that brings integrated value.
The OP reflects and demonstrates how Prelude will, in a credible and affordable way,
achieve its strategic ambitions (including GHG). Key deliverables for the OP process
related to GHGEM include:
• integrated forecast of GHG emissions along with production;
• integrating in plan GHG abatement projects into business costs and establishing an
associated risked GHG abatement target; and
• developing total GHG emission and intensity-based targets for the following calendar
year.
The OP is developed using inputs and assumptions from various functions but for
GHG, inputs and assumptions largely come from an integrated production system
model and RAU assumptions developed based on known risks and opportunities
documented in systems like MTO. GHG emissions are an integral part of the OP
process, which uses information from development concepts, production inputs and
assumptions, production forecasts and hydrocarbon maturation, well reservoir and
facility management, decommissioning and restoration, cost, commercial, economic,
financial inputs and assumptions, along with associated risks and opportunities.
Relevant technical authorities and management level signoffs occur from discipline
lines. GHG signoffs are provided by the technical authority (TA2) for process
engineering.
GHG outputs from the OP process include GHG targets (GHG intensity, total emission
and abatement) approved by senior asset management, which are usually set based
on the mid case (P50), are measured and regularly tracked. These targets provide
input into Shell Group Scorecard. Targets also reflect Shell Group’s climate ambitions,
and reinforce its priorities and desired behaviours at Shell Group level. These may be
different from the plan to set direction and apply stretch.

Fuel and Flare Forum

The Fuel and Flare Forum brings together expertise from relevant functions in Prelude
FLNG to consistently manage the risks of GHG and Energy performance. The Fuel and
Flare Forum's objective is to:
• Review Prelude’s monthly GHG performance with discussion around the
sources and reasons for flaring. Where applicable, develop and investigate how
to learn from this and create opportunities to reduce emissions.

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• Enable cross facility understanding and collaboration of Prelude’s current

threats/opportunities to reduce fuel emissions and achieve no routine
operational flaring.
• Track implementation of the more operational abatement tactics and ensures
that out-of-cycle abatement opportunities are identified and progressed without
having to wait for the annual process.
• Review and prioritise GHG related technical queries raised by the asset team
via the SAP Z8 process.
• Drive continuous improvement to reduce GHG emissions by monitoring and
prioritising improvement opportunities for GHG reduction.
• Ensure accurate information and forecasting is available to support reporting
and decision making activities.
• Ensures proactive action is taken to ensure EPO’s are on track in line with EPS
9.14-9.16. This will include actions such as:
o accelerate abatement projects already in plan
o revisit ALARP assessment for abatement projects currently not in plan to
see if ALARP criteria are met become in-plan now
o review (and look to accelerate) maintenance priority for passing valves and
other GHG abatement related maintenance items
o review short-term fuel strategy (e.g. switching fuel source)

10.2 Organisation, Roles and Responsibilities

The overall structure of Prelude FLNG is summarised in Figure 10-10. The core
organisation of Prelude consists of the Prelude FLNG Asset Manager, reporting to the
Vice President Prelude. The Asset Manager is accountable for the safe and
environmentally responsible operation of Prelude.
The facility Offshore Installation Manager (OIM) who reports into the Production
Manager has overall field authority for work on and within the safety zone. The offshore
organisation is supported by a core onshore organisation which includes Shell’s
technical and other support departments providing both frontline and long term
engineering services including but not limited to:
• Engineering and maintenance standards/guidelines and supporting
governance processes;
• Engineering and maintenance strategies, systems and applications to
support and optimise operations; and
• Coordination of production engineering and maintenance execution
processes and resources.
As required by Regulation 14(4) this section of the Implementation Strategy establishes
a clear chain of command that sets out the roles and responsibilities of personnel in
relation to the implementation, management and review of the EP, ranging from senior
management to operational personnel that support Prelude and support vessels. Roles
and responsibilities associated with emergency management arrangements are
detailed in Table 10-14.

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The roles, responsibilities and accountabilities for processes undertaken are detailed in
the Business Management System and individual’s job descriptions. General
responsibilities associated with this EP for key personnel are summarised in Table
10-4.

Figure 10-10: Prelude Asset Core Organisation Structure

Table 10-4: Key Responsibilities

Position Responsibilities
Systems, Practices and Procedures
• Accountable for the overall operation of the Facility.
• Accountable for ensuring all necessary regulatory approvals
are in place to operate.
• Accountable for the implementation and compliance of the EP.
Prelude Asset Manager • Accountable for safe, efficient and environmentally sound
operation of the Facility in accordance with the EP, legislative
(EP Owner)
requirements and Shell’s policies and standards.
• Custodian of communication with all regulatory agencies
required to operate the Facility.
• Accountable and responsible for agreeing and meeting KPIs
and environment initiatives from annual Plans and reviewing
environmental performance to drive continuous improvement.

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Position Responsibilities
• Accountable for the implementation of stakeholder consultation
as per the description in this EP and in compliance with
regulations.
Systems, Practices and Procedures
• Accountable for overall engineering compliance with all
legislative requirements.
• Accountable for ensuring that the management of change and
engineering support workflow systems and processes are
Integrated Engineering adhered to.
Manager
• Accountable for compliance with all engineering elements of
business processes within the defined area/asset including the
management of change workflow.
• Accountable for achievement of all engineering KPIs, risk
assessment and mitigation.
Systems, Practices and Procedures
• Accountable for overall day-to-day process engineering,
production chemistry and laboratory compliance with all
legislative requirements.
• Accountable for process optimisation.
Production Support Manager
• Accountable for ensuring that the process surveillance,
production chemistry and laboratory workflow systems and
processes are adhered to.
• Accountable for achievement of all Technology KPIs, risk
assessment and mitigation.
Systems, Practices and Procedures
• Responsible for the overall operation of the Facility.
• Responsible for the implementation and compliance of the EP.
• Responsible for safe, efficient and environmentally sound
operation of the Facility in accordance with the EP, legislative
requirements and Shell’s policies and standards.
• Responsible for agreeing and meeting KPIs and environment
initiatives from annual Plans and reviewing environmental
performance to drive continuous improvement.
Resourcing, Training and Competencies
• Puts in place adequate resources (technical, environmental,
Production Manager engineering, information, financial) to implement and meet all
requirements of the EP.
• Establishes and maintains a workforce with the necessary
knowledge, skills and competencies to operate and maintain
the Facility in accordance with the requirements of the EP.
Monitoring, Auditing, Non-conformance and Emergency
Response
• Accountable for monitoring performance against the EP.
• Accountable for implementing agreed assurance activities and
monitoring close out of actions.
• Accountable for incident notification, reporting and investigation
in line with Shell and EP requirements.

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Position Responsibilities
Systems, Practices and Procedures
• In charge of the Prelude FLNG facility and the field.
• Accountable for the implementation of the EP at the facility.
• Ensures offshore personnel comply with regulatory
requirements and Shell’s policies and standards.
• Accountable for ensuring all teams operate in a safe and
reliable manner to meet production targets within the defined
operating and technical integrity envelopes.
• Accountable for the Permit to Work governance, process and
permit requirements.
• Implements environment initiatives from the Integrated Activity
Plan including review of environmental performance to drive
continuous improvement.
• Ensures effective communication with workforce on
environmental performance.
• Accountable for effective and appropriate handovers between
shifts.
Resourcing, Training and Competencies
OIM • Provides appropriate offshore resource allocation to meet the
EP requirements including performance outcomes, standards
and measurement criteria.
• Accountable for the performance and development of
production, services and maintenance teams and ensuring
capability and competency across all shifts.
Monitoring, Auditing, Non-conformance and Emergency
Response
• Accountable for monitoring performance against the EP.
• Implements environmental assurance activities and audits and
implementing and monitoring close out of recommended
actions.
• Ensures incidents are reported and investigated in line with
Shell Australia standards and EP requirements, with
appropriate actions initiated and closed out.
• Responsible for acting as the Incident Controller during
emergencies.
• Responsible for ensuring exercises and drills are carried out
such that the facility’s ability to respond effectively to an
emergency is assured.
Systems, Practices and Procedures
• Responsible for ensuring compliance to all environmental
regulatory requirements as defined in this EP and Shell
standards and procedures.
Offshore Production and
Services Coordinators • Accountable for the day-to-day operations of the facility
including effective shift handover, completion and logging of
operator routine environmental performance.
• Responsible for leading and coordinating a multi-disciplined
team performing specific duties to support the asset integrity of

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Position Responsibilities
the facility, including helicopter operations, vessel movements
and movement of goods and materials.
• Implements environmental initiatives.
Resourcing, Training and Competencies
• Resource planning and allocation for the operations team
• Management and coordination during emergencies
Monitoring, Auditing, Non-conformance and Emergency
Response
• Responsible for assisting with assurance activities and incident
reporting and investigation as required.
Systems, Practices and Procedures
• Responsible for ensuring compliance to all relevant
environmental regulatory requirements as defined in this EP
and Shell standards and procedures.
• Responsible for the execution of the maintenance work plan to
manage asset integrity of the facility and to support the EP.
• Accountable and responsible for permits and isolation for all
Offshore Maintenance frontline maintenance activities.
Coordinator Resourcing, Training and Competencies
• Resource planning and allocation for the maintenance team.
• Management and coordination during emergencies
Monitoring, Auditing, Non-conformance and Emergency
Response
• Responsible for assisting with assurance activities and incident
reporting and investigation as required.
Systems, Practices and Procedures
• Liaises with OIMs and Coordinators/Team leads on day-to-day
management of environmental risks and issues.
• Identifies opportunities for continuous improvement and
communicates these to the OIMs and Shell Australia
Environment Team.
Resourcing, Training and Competencies
• Coaches and assists in implementing environmental
improvement initiatives.
Offshore HSSE Advisors
• Coaches relevant personnel understand the requirements in
the EP applicable to their role.
Monitoring, Auditing, Non-conformance and Emergency
Response
• Assists with the ongoing promotion of environmental
performance at the facility including environmental reporting,
monitoring and review.
• Assisting with assurance activities and incident reporting and
investigation as required.

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Position Responsibilities
Systems, Practices and Procedures
• Overall coordination of environmental management across
Shell Australia to ensure the performance outcomes, standards
and measurement criteria of the EP are met.
• Ensuring the organisation understands and adheres to
regulatory requirements and environmental management
system.
• Guiding and driving the direction of environmental management
across the organisation, maintaining alignment with Shell
Group’s environment direction.
• Providing support on environmental standards and EP
compliance through the Shell Australia assurance programs.
Shell Australia Environment • Monitoring and communicating to the organisation any relevant
Manager changes to legislation, policies and regulator organisation that
may impact the EP or the business.
• Functional support on developing and maintaining appropriate
environmental processes for Prelude.
Resourcing, Training and Competencies
• Supporting the Divisional environmental performance through
implementation of effective environmental training programs.
Monitoring, Auditing, Non-conformance and Emergency
Response
• Monitor and review progress against environmental
improvement plans, targets and KPIs with divisional
management to drive continuous improvement.
Systems, Practices and Procedures
• Monitor and review progress against EP, targets and KPIs with
Prelude management to ensure compliance with the EP and
Prelude HSSE manager drive continuous improvement.
• Escalate to Prelude Leadership Team any potential
environmental issues and non-compliances to ensure
ownership by the line.
Systems, Practices and Procedures
• Ensuring appropriate personnel have access to the EP and
understand the outcomes, standards and measurement criteria
and their environmental responsibilities for the activity.
• Liaising with applicable regulatory authorities and stakeholders
as required.
• Develops risk reduction strategies and defines Performance
Standards.
Prelude Environment Lead
• Facilitates ALARP & Acceptability reviews.
• Update of the EP as required.
• Facilitate and provide coaching for environmental improvement
plans.
Resourcing, Training and Competencies
• Developing and maintaining environmental training, and
coaching materials for deployment to Prelude organisation.

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Position Responsibilities
Monitoring, Auditing, Non-conformance and Emergency
Response
• Responsible for environmental monitoring and reporting
requirements from the EP including environmental performance
and compliance reporting.
• Monitoring progress against environmental improvement plans.
• Participating in environmental audits/inspections to ensure
regular checking of compliance to this EP. Communicating
findings to management and assisting with close out of actions.
• Assisting with review, investigation and reporting of
environmental incidents.
• Responsible for preparing and implementing Prelude
External Relations Advisor Stakeholder Engagement Plan.
• Responsible for taking action immediately to rectify any
environmental incident on the vessel.
• Implementation of the EP on board the vessel.
• Ensure effective operation of the vessel, taking into account
relevant environmental aspects.
• Communication of vessel environmental management activities
on board.
• Maintain administration of vessel’s environmental management
Vessel Masters system requirements
• Ensure all crew members comply with the EP.
• Manage any spills per SOPEP.
• Responsible for ensuring cetacean sighting recording is
undertaken.
• Maintain good housekeeping and cleanliness around the
vessel.
• Compliance with DAFF and other marine regulations.
• Ensuring implementation of this EP for the contractor’s scope
of work.
• Ensuring contractors have adequate environmental capability in
Contract Holders order to execute their scope of work.
• Reviewing and provide assurance over contractor
environmental performance.
• Complying with standards and procedures that apply to their
area of work.
• Immediate reporting of any environmental hazards or incident
to the supervisor.
• Understanding the environmental risks and controls applicable
All personnel to work.
• Following instructions from the OIM or supervisor with respect
to environmental protection and measurement criteria outlined
in this EP.
• Undergo environmental training as required by role and activity.

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Position Responsibilities
• Carry out assigned activities in accordance with approved
procedures and the EP.
• Stop any operation or activity that is deemed to present an
unacceptable risk to the environment.

10.3 Competence and Inductions

10.3.1 Competency
All personnel required to work on Prelude installation activity are required to be
competent to perform their required tasks. However, there is a subset of the workforce
whose duties are sufficiently critical to the safe running of our operations that they
require Competence Assurance. These are people in HSSE Critical Positions who are
directly responsible for the safety of operations. These positions include the following:
• HSSE Critical Leader positions
o Senior Management position at Leadership Team level with Operational, Technical
or Engineering responsibilities with RAM red or yellow risks
o Operational, Technical or Engineering position responsible for defining ALARP for
RAM red or yellow Risks for a project, technical department or asset
o Operational, Technical or Engineering position accountable for delivering
ALARP for RAM red or yellow Risks for a major asset, group of small assets,
major project or group of small projects.
• Technical Authority Level 1 and Level 2
o Technical Authority Level 1 or 2 roles, which involve design, implementation and
maintenance of barriers established for managing hazards with RAM red or yellow
risks are deemed HSE Critical.
o Required to be ‘Skill’ level at relevant technical and operational competencies.
• Frontline Barrier Management (FLBM)
o Positions directly responsible for implementing or maintaining barriers established
for managing hazards with RAM red or yellow risks. These are mainly the
production, maintenance and service technicians.
Personnel in HSSE Critical Leader positions are required to demonstrate the required
level of competency in Lead, Prepare and Apply HSSE & SP Risk Management,
subject to their Proficiency Profile. The HSSE critical leader positions are required to be
skilled on the Lead, Prepare and Apply HSSE & SP risk management competency
elements. The current list of HSSE Critical Leader positions and their competence
requirements is maintained by Shell Group.
Shell has a defined set of Technical Authorities. Where a Technical Authority is not
available within Shell, access is available to the Shell Global Technical Authority pool.
A list of competent TAs is maintained globally through the Discipline Authorities Manual
(DAM).
The register assigns a HSSE profile to each role and defines required proficiency levels
for each profile. After assessment of individual competencies against position
requirements, proficiency gaps will be addressed in training and coaching.

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Additionally, all Shell positions in the organisation have detailed job descriptions
including Competency Requirements. Company personnel working offshore require
mandatory training as defined in the Training Strategy and Competence Management
Plan. This matrix specifies the required HSSE & SP competence and training
requirements for Shell staff who carry out specific activities during the Offshore
Execution Phase. This plan also specifies training providers who are approved to
provide such training. The training matrix is built based on requirements for Shell
Group HSSE & SP Control Framework and Australian regulatory requirements. This
plan also covers the minimum HSE training requirements for visitors.
Contractors have their own Competence requirements in place as described in Section
10.1.3. Training records of all personnel will be maintained and the training program
will be reviewed on a regular basis.

10.3.2 EP Training
OPGGS(E) Regulation 14(5) requires that the implementation strategy must include
measures to ensure that each employee and contractor working on, or in connection
with, the activity is aware of their roles and responsibilities in relation to the EP.
All employees and contractors working on or in connection with Prelude with defined
responsibilities to fulfil as part of the EP are required to attend EP Training that is
formally tracked.
The Prelude EP Training shall cover the following items:
• Legislative requirements
• Ecological and socio-economic values of the project area
• Key environmental aspects, impacts and risks
• Shell’s key EP Commitments
• Environmental management requirements, such as:
o Liquid discharges management
o Drainage system management
o Emissions management
o Chemical and hydrocarbon management
o Waste management
o Marine fauna interaction
o Reporting of environmental incidents (such as spills)
o Emergency Response (including spill response).

On arrival at the facility or vessel, personnel (including short-term visitors) attend an

onsite orientation designed to familiarise them with the general operations and location
of key areas. The orientation explains the site-specific safety, environmental and
emergency response aspects.

10.4 Monitoring, Assurance and Incident Investigation

This section of the EP outlines the measures undertaken by Shell to regularly monitor
the management of environmental risks and impacts of the Prelude activities against
the performance outcomes, standards and measurement criteria, with a view to

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continuous improvement of environmental performance. The effectiveness of the

Management System is also reviewed periodically as part of the monitoring and
assurance process.

10.4.1 Environmental Performance Monitoring

Monitoring and review of environmental performance of the Prelude FLNG facility is
done in a number of ways including monitoring of emissions and discharges, and
through the use of various tools and systems. These monitoring systems meet the
requirements of the following:
• Shell Australia Environmental Reporting Procedure (HSE_GEN_003179)
• Shell Australia Offshore Environmental Regulatory Approvals & Compliance Procedure
(HSE_GEN_003180).

In accordance with OPGGS(E) Regulation 14 (7), the implementation strategy must

provide for sufficient monitoring of, and maintain quantitative records of, emissions and
discharges (whether occurring during normal operations or otherwise), such that the
record can be used to assess whether the EPOs and EPSs in the EP are being met.
Parameters that are monitored and recorded during operation of the FLNG facility are
detailed in relevant parts of Section 5.0 and in the performance outcomes, standards
and measurement criteria table in Section 6.0, and are summarised in Table 10-5. *
Where online analysers are the primary monitoring equipment/methodology and where
not specified, the intent is always that if the online analyser is not available, manual
sampling or estimation would be used as a contingency.

Table 10-5: Emissions and Discharges Monitoring for Prelude FLNG Facility

Monitoring
Parameter to Monitoring EP
Source Equipment/ Records
be Monitored Frequency Reference
Methodology*

Drainage Oil Content On-line On-line analysers PI Database Section

Discharge 9.9
Flow

Treated Flow On-line On-line analysers PI Database Section

Produced 9.9
Water Total Petroleum
Discharge hydrocarbons

Chemical Per Table 10-7 Sampling and External laboratory

characterisation third-party reports
and WET laboratory
sampling analyses
analysis per
Table 10-7

Cooling Flow On-line On-line analysers PI Database Section

Water 9.9
Discharge Free chlorine
Temperature

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Monitoring
Parameter to Monitoring EP
Source Equipment/ Records
be Monitored Frequency Reference
Methodology*

Brine Flow On-line On-line analysers PI Database Section

Discharge 9.9

Boiler Blow- Flow On-line On-line analysers PI Database Section

down 9.9
Discharge pH

Neutralisation Flow On-line On-line analysers PI Database Section

Tank 9.9
Discharge pH

Emissions Fuel On-line (Flow) Hydrocarbon & PI Database Section

from boilers consumption Air Emissions 9.10 and
On-line Gas Accounting NPI and NGER Section
GHG emissions Chromatographs Methodology reports 9.11
Engineering
Calculations

Particulate Once off within Stack sampling External laboratory Section

matter (PM) 18 months and third-party reports 9.10
performance laboratory
Sulphur dioxide testing analyses NPI Reports
(SO2) completion for
Nitrous oxide specified plant
NOx) equipment.
Frequency of
Carbon this stack
monoxide (CO) sampling will be
reviewed based
on performance.

Diesel fuel Sulphur content As required Delivery Delivery certificates Section

used on the (every delivery) certificates 9.10 and
FLNG and Section
support Laboratory 9.11
vessels sampling

Volume used Monthly Delivery PI Database

certificates and
storage tank Delivery certificates
volumes

Flaring Total gas flared On-line (flow) Hydrocarbon PI Database Section

emissions Accounting 9.10 and
GHG emissions Engineering Methodology NPI and NGER Section
Calculations reports 9.11
Sulphur dioxide
(SO2)
Nitrous oxide
NOx)
Carbon
monoxide (CO)

Acid gas Total gas On-line (flow) Hydrocarbon PI Database Section

vented vented Accounting 9.10 and
Engineering Methodology NPI and NGER
GHG emissions Calculations reports

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Monitoring
Parameter to Monitoring EP
Source Equipment/ Records
be Monitored Frequency Reference
Methodology*
Section
9.11

Fugitive GHG emissions Online (HP Hydrocarbon NPI and NGERS Section
emissions separator flow) Accounting reports 9.10 and
Methodology Section
Engineering 9.11
Calculations

Waste Hazardous Monthly Waste Monthly waste Section

generation Waste records/manifests reports 9.12
Non-Hazardous
Waste

Accidental Volume of As required If unmetered, Incident reports in Section

releases of accidental volumes will be Fountain Incident 9.13.
hydrocarbons release estimated based Management
or chemicals on technical data
Characteristic and evaluations
of release (e.g. known well
flow rates,
production
flowrates,
pressure,
duration of
release and
known inventory
volumes)

Ad Hoc liquid Water quality As required. Laboratory MOC records Section

discharges sampling as 9.9.
from FLNG Volume of required.
discharge

10.4.2 FLNG Liquid Discharges Adaptive Monitoring and

Management Framework
Overview
This section contains details of an adaptive monitoring and management framework
(framework) for Prelude FLNG water discharges. The framework’s overall aim is to
continually manage impacts from Prelude FLNG water discharges to ALARP and
acceptable levels. Note that the primary focus of this framework is on PW discharges
given this stream presents the greatest predicted impact of all the discharges (Section
9.9) when assessed in isolation. However, potential contaminants from other
discharges are also included where relevant based on nature and scale of the
associated impacts. Methodologies for the monitoring program will be consistent,
allowing results to be compared and trends to be analysed over time.
The framework ensures the nature, extent, and potential effect of the PW, CW and
other discharges are adequately assessed, and helps determine and assess the nature
and scale of changes to water quality in relation to applied triggers and thresholds. The
framework comprises several monitoring program components, as summarised in
Table 10-6 below and conceptualised in (Figure 10-11). The framework is further

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detailed and proceduralised in the Prelude Liquid Discharges Monitoring and

Management Procedure.
Table 10-6: FLNG Wastewater Adaptive Monitoring and Management Framework –
Monitoring Programs

Monitoring Program Frequency Further Detail

Topsides monitoring Ongoing (Refer Table 10-5) Refer to Table 10-5

Additional monitoring as a result of trigger and Table 10-7
exceedances
PW Chemical Characterisation Annually Refer to Table 10-5
Additional testing as a result of trigger and Table 10-7
exceedances or significant change
WET testing Commence 6 monthly testing for 18 months Refer to Table 10-8
starting no later than Q2 2021, then triennial
thereafter.
Additional WET testing as a result of trigger
exceedances or significant change (Table
10-12)
Mixed Discharges WET test: Once off, after
initial field water sampling survey and
coinciding with next scheduled PW WET
testing
Field water quality sampling 5-yearly Refer to Table 10-9
Additional field sampling as a result of trigger
exceedances
PW Model verification One planned model verification event within Refer to Table
the 5-year validity period of this EP. 10-10
Additional model verification as a result of a
trigger exceedances
PW sediment quality sampling Initially by 2030 or sooner Refer to Table
10-11

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Figure 10-11: Conceptual diagram of adaptive monitoring and management framework

FLNG Topsides Monitoring

The overarching objective of the topsides monitoring program is:
• to use data collected topsides from PW and CW discharge, combined with modelling
predictions, to assess whether the defined threshold/trigger values are likely to be
exceeded beyond the predicted mixing zone(s) and for how long this has or will continue
to occur (duration).
The main components of topsides monitoring to support the ongoing impact
assessments, as well as other wastewater data are listed in Table 10-5, Table 10-7 and
Table 10-8.

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Table 10-7: FLNG Wastewater Discharges – Topsides Monitoring

Study/Activity Objectives Timing Details of Study/Activity Thresholds/Further actions

Routine operational Enable management of key Ongoing throughout Refer to Table 10-5. No action required if parameters/constituents are within predicted
monitoring of discharges discharges within set triggers, operations at agreed and assessed ranges. Where these levels are exceeded, the
(Refer to Table 10-5 for EPS and EPOs. intervals (see Section relevant actions in accordance with the Prelude Liquid Discharges
specific components) 9.9 and Table 10-5). Monitoring and Management Procedure (HSE_PRE_012355) are to
be implemented and assessment undertaken against the relevant
EPS to determine if the incursion constitutes a Recordable incident.
Specific analyses, sample
PW Chemical Determine PW chemical Annually collection methods and An assessment of the annual PW chemical characterisation results
Characterisation constituents and concentrations storage times will be will be made against the most recent WET testing results (noting
to monitor changes in chemical Upon significant that WET testing will move to a triennial basis). If the chemical
changes to the PW confirmed with a certified
composition through time and laboratory undertaking characterisation data indicates WET testing thresholds would be
identify long-term trends. stream (Refer to Table exceeded (mixing zone extent based on dilution contours and 99%
10-12) analyses.
species protection concentration 99% times) the following actions
Where substantial chemical would be undertaken:
changes occur, these will • compare composition against the applicable ANZECC DGVs,
be investigated for impact or other defined trigger values;
on effluent density, which • understand what is leading to changes in chemical composition
may decrease mixing, and (through analysis of operating conditions, topsides monitoring
WET test toxicity. to understand the likely major contributors to changes in PW
chemical composition).
By no later than 2028, a review of PW monitoring information will be
conducted, with the view to consider if it is suitable to still wait until
2030 to carry out the planned sediment monitoring field monitoring
outlined in Table 10-11.

WET Testing
Table 10-8: Summary of WET Testing
Study/Activity Objectives Timing Details of Study/Activity Thresholds/Further actions
PW WET Testing Determine if predicted Commence 6 monthly WET testing is done for the direct Dilution targets from the RPS model used to establish the
impacts are within the testing for 18 months toxicity assessment of the whole PW Mixing Zone will be investigated after each round of WET

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mixing zone set for PW starting no later than Q2 effluent in order to allow for the testing, to determine performance against the Target and
and monitor changes in 2021, then triennial assessment of additive effects from manage if necessary, following an assessment of the
toxicity through time. thereafter. different chemicals and constituents. ‘representativeness’ of the effluent tested. The Target (mixing
Upon significant changes This is carried out using recognised zone extent based on dilution contours and 99% species
(Refer to Table 10-12) ecotoxicity assessment methodology protection concentration) will be modified based on a rolling
defined in ANZECC/ARMCANZ average of the 99% species protection concentration from the
(2000) in a NATA accredited three most recent, and representative, WET test rounds,
laboratory. WET testing results may provided it never exceeds the current overall mixing zone of 1
be used to derive more relevant site- km.
specific thresholds for species The WET testing data would be extrapolated against the
protection, than the full suite of model to determine the number of dilutions required to
contaminants outlined in Table 10-7 achieve 99% species protection levels 99% of the time. If this
for water quality. result showed that the ANZECC/ARMCANZ 99% species
protection levels were being exceeded more than 5% of the
Testing on a full suite of species time beyond the predicted mixing zone, additional
(minimum of five) for the initial two management measures would be considered.
sampling occasions, then suite WET test results will be combined with the PW
reduced to a minimum of two characterisation to investigate the chemical basis of effluent
species for succeeding samples in toxicity using such methods as generic environmental hazard
first 18 months of the sampling evaluation based on chemical composition or Toxicity
regime. Full suite of species Identification Evaluation to understand drivers and identify
(minimum of five) will be conducted possible mitigations.
for each triennial sampling event Changes (increased toxicity that results in mixing zone larger
thereafter. than predicted) in reduced suite of toxicity tests would trigger
testing with full suite and chemical characterisation analyses if
results were from the reduced WET testing suite.
If the WET testing evaluations show that the discharge
thresholds are potentially being exceeded at the edge of the
predicted mixing zone, an investigation as to the cause of the
higher than expected toxicity will be undertaken to determine
likely causes and available management options:
• Understand the magnitude of likely exceedance (via
interrogation of the verified dispersion model) and check if
it is greater than the impact footprint (mixing zone)
predicted in the EP.

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• Understand what is leading to the increase in toxicity
(through analysis of operating conditions, topsides
monitoring and interrogation of the WET testing and
chemical characterisation results to understand the likely
major contributors to overall toxicity).
‘Mixed discharges’ WET To determine if the Once off, after initial field Modelled dilution rates and results No further action is required if the toxicity of the mixed
Testing toxicity of potential water sampling survey and from the field water sampling survey discharge WET test is less than the corresponding PW WET
comingled discharges coinciding with next will be used to identify the test.
are greater than the PW scheduled PW WET appropriate discharge co-mixing
discharge alone and if testing ratios to be used to mimic what is In the event the mixed discharge WET test is found to be
so, to understand: To also be carried out at occurring around the FLNG. more toxic than the PW WET test;
• if is confirms the the same time as WET 1. The results of the monitoring will be validated when the
model is predicted testing for PW. WET testing is done for the direct next infield water quality monitoring occurs; and
to still be toxicity assessment of the whole PW 2. A review of chemical characterization results will be used
conservative. effluent in order to allow for the to help inform the source for potential increased toxic
• if comingled assessment of additive effects from effects from the mixing of discharges including options to
discharges have different chemicals and constituents. potentially reduce toxicity; and
significant additive This is carried out using recognised 3. If (1) above confirms toxicity of mixed discharge is still
or synergistic ecotoxicity assessment methodology greater than PW, further mixed discharge WET tests will
impacts defined in ANZECC/ARMCANZ be carried in when future scheduled PW WET tests occur
• the likely major (2000) in a NATA accredited to enable further comparison.
contributors to laboratory. WET testing results may
overall toxicity in be used to derive more relevant site-
comingled specific thresholds for species
discharges protection than the full suite of
contaminants outlined in Table 10-7
for water quality.
Chemical characterisation will be
carried out on the same samples that
have the WET test carried out on
them to enable potential
identification of the driver of toxicity.

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Field Monitoring

Table 10-9: Summary of the routine/planned infield monitoring campaigns

Study/Activity Objectives Timing Details of Study/Activity Thresholds/Further actions

Water Column Determine if the PW model is One planned routine Specific sampling locations, contaminants, sample collection If results indicate the PW model is
Sampling1 conservative or not (i.e. confirm sampling event within the methods, including quality control and assurance, and storage not sufficiently conservative, a
the model underestimates the 5-year validity period of times will be confirmed with the environmental consultants new more accurate model will be
actual level of dilutions at the this EP. designing the programme to ensure the objectives of the field established to determine with
edge of the mixing zone). 51 monitoring are met. The survey design and methods used will higher confidence if the PW is
also be independently reviewed by a qualified subject matter meeting compliance/non-
expert prior to finalizing the design and methods as an compliance at the edge of the
additional assurance to ensure the objectives of the survey are mixing zone for PW with WET test
achieved. results and relevant ANZECC
There will be an initial need to confirm trajectory of the guidelines (99% species
discharge to ensure sampling is occurring within the plume. This protection limits, 99% of the time).
may be achieved by visual assessment, remote sensing or real
time sensors deployed from vessels running transects, injection In the highly unlikely event the
of dyes or other methods and will also help identify potential co- results indicate the PW model is
mingling zones. not conservative and impacts to
water quality are greater than
Given the FLNG weather vanes and orientation is predominantly have been predicted within the
influenced by the currents, discharges will typically flow along EP, an investigation will be
the hull towards the stern and away from the facility. Along this initiated to determine the cause of
bow to stern gradient, different discharges can comingle and the impacts and engineering and
mix with discharges entering from upstream (for assessment of other solutions which could be
potential comingling liquid discharge plumes). The spatial considered to address the issues.
separation and different chemistry of the various discharges In this circumstance also, further
enables the dilution of individual discharges as well as infield monitoring targeting
comingling of multiple discharges to be investigated. Sampling potential additive effects from
will occur at optimised locations along this gradient with precise

51Preliminary scoping for infield water quality sampling studies carried out by Shell between 2018 and 2020 have shown that it is not reasonable or realistically achievable to extend the
objectives of the study beyond those outlined above because of the complexities and realities of conducting infield water quality sampling for low concentration discharges in the open ocean
environment at any meaningful distance from the discharge source around a mobile operating facility.

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locations adjusted to match the predicted levels of dilutions and other discharge streams or co-
proximity of the specific discharges relative to each other. mingling with other discharges
Each water sample will be analysed for the full suite of would be carried out.
measured contaminants to determine dilution of PW as a single
waste stream as well as to assess the influence of comingling of
different discharge streams on the PW plume.
Sampling should be conducted within a single tidal cycle at a
time of reasonable tidal flow and when thrusters or wind are not
holding the FLNG against the tide.
Under most conditions discharges are likely to flow along the
hull of the FLNG towards the stern, restricted to a small distance
laterally from the hull. Along this bow to stern gradient, different
discharges are added and mix with any discharges entering
from upstream.
Given the results of the liquid discharges cumulative impact
assessment outlined in section 9.9.3 has shown any
consideration of other discharges will add further conservatism
to the already conservative impact assessment, there is no
planned infield monitoring and assessment of other discharges
apart from the PW discharge.

1 – As further detailed in Section 9.9, routine monitoring of sediment quality and benthic habitats will not be undertaken for the duration of this EP due to no credible impact pathway or no
environmental effects or damage predicted.

PW Model Verification
Table 10-10: Summary of the PW Model Verification
Study/Activity Objectives Timing Details of Study/Activity Thresholds/Further actions

PW Model Verification Verify through field One planned model Initially dye studies, or other suitably Validate model predictions on mixing and/or adjust
sampling and observation verification event within the robust method, will be used to confirm the model to align with measured dilution.
that topside monitoring 5-year validity period of this trajectory of discharges and, the spatial
combined with the EP. pattern of dilution and co-mingling of Confirm individual mixing zones and extent of co-
modelling predictions discharges. This may be achieved by mingling of different mixing zones (if reasonably
provides a conservative visual assessment, remote sensing, real practicable)

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prediction of the extent of time sensors deployed from vessels Identify the relationship of the Target Dilution derived
the mixing zone for PW running transects, injection of dyes or from WET testing with ANZECC guidelines for
discharges other methods and will also help identify individual chemicals (99% species protection limits,
co-mingling zones as a secondary 99% of the time).
objective.
If results of the PW Model verification indicate the PW
model is not sufficiently conservative, a new more
accurate model will be established to determine with
higher confidence if the PW is meeting
compliance/non-compliance at the edge of the mixing
zone for PW with WET test results and relevant
ANZECC guidelines (99% species protection limits,
99% of the time). This would also trigger review of the
PW impact assessment and assessment under the
Shell MOC Manual as applicable to determine if any
changes in the impact profile are significant.
In the highly unlikely event the results indicate the PW
model is not conservative and impacts to water quality
are greater than have been predicted within the EP,
an investigation will be initiated to determine the
cause of the impacts and engineering and other
solutions which could be considered to address the
issues.

PW Sediment Quality Monitoring

Table 10-11: Summary of the PW Sediment Quality Monitoring
Study/Activity Objectives Timing Details of Study/Activity Thresholds/Further actions

PW sediment quality Verify the predicted level To be initially done by 2030 The details of this study will be known Update risk assessments/predictions.
sampling of impacts to sediment or sooner. once the relevant activities are conducted.
quality immediately However, a scientifically robust sampling Determine major causes of benthic impacts by
surrounding the Prelude Opportunities for cost design will be implemented to enable correlation of the concentration of the different
FLNG facility from the PW efficiencies will be verification of the predicted level of

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discharge through field considered in doing the impacts to sediment quality immediately contaminants from PW discharge (and others
measurements. monitoring earlier. e.g. surrounding the Prelude FLNG facility potentially) found in the sediments.
conducting sediment from the PW discharge through field
monitoring in conjunction measurements.
with water quality
monitoring. Suitably qualified personnel (e.g. external
independent consultants) will be engaged
to design and carry out the monitoring.
Considerations of lessons learnt from
other industry monitoring studies will be
obtained where possible. Baseline
monitoring suitability will also be
considered in the design of the
monitoring. Design will also consider
where likely expected worst impacts are
predicted given prevailing conditions
onsite.
Design of the study will be consistent with
the relevant ANZECC study design
approach available at the time, noting
changes in technology, sampling design
and methods are likely to change
between now and when potential
sediment quality monitoring is carried out.

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PW Changes Requiring Additional Assessment

In addition to the routine/planned monitoring activities outlined in Table 10-5 to Table
10-10, this adaptive management framework also contains potential triggers for
additional studies/verification when there are significant changes to the PW discharge
characteristics.
Additional studies may be in the form of desktop analysis, modelling studies, additional
chemical characterisation and/or WET testing and monitoring of the receiving
environment. If the assessment shows a potentially significant increase in the
environmental impact consequence ranking, then further corrective and/or contingency
actions may be required to ensure impacts are reduced to ALARP and acceptable
levels. Potential triggers for additional studies associated with PW changes are
presented in Table 10-12.
Table 10-12: Prelude PW Discharge Additional Studies Triggers Due to Potential Changes

Potential Changes Triggers Planned Verification Actions

Change in process Changes to production or process
chemicals (increase in chemicals are assessed in accordance to
chemical the Shell Australia Chemical Management
concentration/dosing above Process (Section 10.1.10). If there is
the design envelopes or identified increase in environmental
impact profile of chemicals impact, additional desktop analysis (e.g.
Significant change to proposed) modelling study) and/or WET testing or
chemical additive profile chemical characterisation may be
conducted.
Active constituents of the process
chemicals may also specifically be added
to the topsides monitoring program if
practicable.
PW (formation water) If there is a change in reservoir
comes into Prelude from a characteristics (new wells or new
different reservoir. reservoir), desktop analyses will be
Change in PW source undertaken. If desktop analyses indicate
characteristics potential increase in environmental risk,
further characterization or toxicity
assessments are conducted to verify
environmental impacts.
Increase in discharge rate If there is increase from maximum design
or reservoir water cut from basis of the PW system (165m3/hr) in the
maximum design basis of discharge rate, desktop analysis (including
the PW system (165m3/hr extrapolation from results of existing
discharge capacity) modelling studies) or additional dilution
modelling is done to predict if the
increased discharge rate exceeds the
required dilution to meet acceptable
concentration levels at the edge of the
mixing zone.

Changes to the Adaptive Monitoring and Management Framework

Any proposed changes to the Adaptive Monitoring and Management Framework given
it is a part of the broader LDMMP will be updated in line with the Shell document
management system requirements.

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10.4.3 IMS Monitoring, Reporting and Adaptive Management

10.4.3.1 FLNG
In accordance with the Prelude FLNG Biosecurity Management Plan (2000-010-G000-
GE00-G00000-HX-5798-00003) the IMS monitoring and adaptive management for the
Prelude FLNG that has been carried out is summarised in Figure 10-12.

Figure 10-12: IMS Monitoring and Adaptive Management completed between 2017 and
2019.
Figure 10-12 illustrates the process described in the Prelude FLNG Biosecurity
Management Plan that has been followed and involved the confirmation of the
presence of suspected IMS of concern on the FLNG between 2017 and 2019. This
employed a number of possible methods such as ROV surveys, collection of samples
of biofouling growth/communities and water sampling for further molecular analysis
(DNA/RNA sequencing) summarised in Section 9.8. The survey and sampling design
involved liaison with numerous parties in order to determine a feasible plan which was
realistic and could achieve the desired outcomes.
Since the last hull integrity survey completed in 2019 (Year 2) no IMS of concern have
been detected on the FLNG. Following the completion of the year 1 and 2 hull integrity
surveys, further monitoring of the Prelude hull will occur on a 5 yearly frequency unless
a further inspection is triggered due to the outcomes of a marine vessel Class
requirement inspection or as part of the Biofouling Risk Assessment for Domestic
Vessels as described in Section 10.4.3.2 and Section 10.4.4.5 respectively.
10.4.3.2 Marine Vessels
Class requirements for hull integrity inspection of vessels include the following:

• In-water inspection every 2.5 years – will include inspection of the anti-fouling coating
integrity. If anti-fouling coating needs re-application, then this will have to be done.
• Dry-docking every 5 years – this will include repair of the anti-fouling coating.

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These hull integrity surveys can also determine if an IMS of concern has established on
a vessel’s hull. If there is reason to do an earlier inspection based on the residual risk
from the FLNG, then this will be coordinated among the vessel owner, an IMS
inspector and the State authority.
The biofouling risk assessment done for all vessels which will operate within the
Prelude Operational Area using the Marine Vessel Biofouling Risk Assessment
template is described in Figure 10-13.

10.4.4 Marine Vessel Assurance

All marine vessels which are planned to be used within the Operational Area are
required to achieve “Positive Vetting” in accordance with the requirements specified in
the HSSE & SP Control Framework – Transport Manual - Maritime Safety. Numerous
assurers are required in order to assure a positive vetting, including Marine SME,
Aviation SME and country security manager, Global Maritime Marine Warranty
Surveyor and the project workstreams responsible for the particular activity to be
conducted. The Marine Vessel Assurance process ensures that the physical controls
are robust, including:
• Navigation Equipment and Aids
• Communication Equipment
• Dynamic Positioning System
• Lifting Equipment
• Emergency shut-down, alarm and lighting systems.

OCIMF OVID is the basis for all support vessel vetting. Additionally, vessels are
screened for class and port state control infractions.
Offtake tankers are positively vetted against the OCIMF inspection.
The following compliance are required for “Positive Vetting” for vessel operating in the
Prelude field, excluding equipment and material transportation vessels.
10.4.4.1 Marine Warranty Survey
All vessels and activities are assessed by the Marine Warranty Surveyor (MWS) on
behalf of Shell’s underwriter. Where required by the Marine Warranty Surveyor (MWS)
and in accordance with Construction All Risk (CAR) insurance rules, a marine vessel
inspection/suitability survey is performed and a Vessel Suitability Report issued by the
MWS with all significant actions and findings closed.
10.4.4.2 Pre-Mobilisation Inspection Report
The Pre-Mobilisation Inspection is conducted to ensure compliance with HSSE, marine
and technical requirements and readiness prior to commencing work. Vessels
(inclusive of their equipment, processes and procedures) are thoroughly inspected and
the inspection report items are closed prior to completion of mobilization.
10.4.4.3 Shell Aircraft International (SAI) Approval
The Shell Aircraft International (SAI) approval ensures that all helidecks on any
selected marine vessels utilized for personnel transport are approved. Furthermore,
helicopters and helicopter refuelling equipment are approved by SAI.

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Biofouling risk assessment for domestic movements

Activities covered: First mobilisation of domestically sourced vessels, either from domestic ports or from other operator facilities
through vessel sharing arrangements

Title
Ballast water excluded from decision tree, as it is to be managed in accordance with the Biosecurity Act, subordination legislation
and the Australian Ballast Water Management Requirements. Phase

Has a recent* biofouling risk assessment been completed Does the vessel have a valid AFC*?
*Valid AFC is defined as within its in-service period based on
and any controls identified implemented? No the manufacturers specifications, and should consider the
*Recent is defined as. since the commencement of operations in that region (i.e. type of coating, age of coating and thoroughness of
Cwlth, State, Territory) application (e.g. extent of unprotected niches?)
Vessel activity – short term and mobile

Yes Yes

Have any extended interactions occurred (e.g. >7 days

alongside) with a conveyance of uncertain/high risk
Does the vessel have a biofouling control/
since last risk assessment? No
Yes treatment systems in use and effective on key
OR
internal seawater systems?
Has the vessel remained for an extended period (e.g.
>7 days) within a Port environment?

No No
Yes

Seek and implement advice from independent

No further management measures
IMS expert

Vessel activity (short term and mobile) examples: supply of goods, assistance to product tanker, bunkering.
Likely vessels utilising this activity profile: PSVs
Vessel activity – long term and in-position alongside

Has a recent* biofouling risk assessment been completed

and any controls identified implemented? No
*i.e. since commencement of operations in that region (i.e. Cwlth, State,
Territory)

Yes

Have any extended interactions occurred (e.g. >7 days

alongside) with a conveyance of uncertain/high risk
since last risk assessment? Seek and implement advice from independent
Yes
OR IMS expert
Has the vessel remained for an extended period (e.g.
>7 days) within a Port environment?

No

No further management measures

Vessel activity (long-term and in-position alongside) examples: construction, installation, maintenance and repair, accommodation support,
Likely vessels utilising this activity profile: ASVs, IMR and construction vessels

Vessel name: [Add here]

Date of last IMS inspection and outcomes: [Add here]

Date of last AFC application: [Add here]
Validity of efficacy of AFC: [Add here]
Internal biofouling control treatment systems (e.g. MGPS): Y/N – details: [Add here]
Vessel history (commences from last known dry dock and AFC application): [Add here]
Biofouling management plan: Y/N – details: [Add here]

OUTCOME: [Add here]

Figure 10-13: Biofouling Risk Assessment Template for Domestic Movements

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10.4.4.4 Group Maritime Assurance System (GMAS) Clearance

A GMAS clearance from the Shell Marine SME must be obtained prior to the
commencement of marine operations on the Project and prior to the contracted marine
vessel entering the Operational Area. This ensures that the above marine vessel
assurance has been completed satisfactorily.
10.4.4.5 Biofouling Risk Assessment for Domestic Movements
In accordance with the Prelude FLNG Biosecurity Management Plan (2000-010-G000-
GE00-G00000-HX-5798-00003) and to ensure the ongoing ‘Low Risk Status’ of the
FLNG, the assessment of biofouling risk will be done for all vessels which will operate
within the Prelude Operational Area using the Marine Vessel Biofouling Risk
Assessment template (Figure 10-13).
The risk assessment will be done by the Vessel Owner/Operator with advice from the
Prelude HSSE Advisor or Prelude Environmental Engineer.

10.4.5 Environmental Assurance

Shell and its contractor’s HSSE Plans make provisions for monitoring, audits and
review. Annual HSSE Plans identify environmental audits and reviews that are to be
conducted for the year. These audits and reviews include internal and external
environmental audits, contractor HSSE audit, waste management audit/review and gap
analyses against HSSE Control Framework Manuals,. As a minimum, an annual
internal environmental audit is planned for the Prelude FLNG facility which will assess
compliance with a risk based selection of internal and external environmental
requirements (including EP requirements) This risk based approach will cover different
aspects, topics and areas of focus areas with a target being to cover assurance of all
internal and external environmental requirements in assurance activities over a
minimum 5 year period.
Shell Group audits are undertaken across all Shell businesses on an intermittent basis.
This auditing process assures the HSSE & SP management system as a whole.
The outputs of the audits and reviews are the corrective actions that feed the
improvement process. Close-out of these corrective actions is monitored and reviewed.
Regular onsite HSSE assurance is conducted on a weekly basis which includes
checking that environmental controls are implemented. Any specific environmental
issues, like any HSSE issues, identified during these assurance checks are raised in
the HSSE Leadership and Assurance meeting and resolved as part of continually
reducing the risks to ALARP and Acceptable levels.

10.4.6 Environmental Knowledge Management Process

To manage the information and knowledge that underpins this EP, Shell has developed
an Environmental Knowledge Management Process. The process involves the periodic
review of EP knowledge against updated information (available to Shell or made
publicly available) to identify any gaps or inconsistencies. The source of new
information may include (but is not limited to):
• Shell Australia EPs, OPPs or other Shell EIAs (Australia and global) in development
and/or accepted.
• Other operator EPs or OPPs as published on the NOPSEMA website.
• Other operator EIAs as made publicly available (Australia and global).

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• Outcomes of Shell monitoring, surveys or other studies as relevant to the EP content.

• Published studies and/or literature relevant to the EP content.
• Legislation databases and government guidelines, policies etc.
• Technical details, operational changes or other information on the project and facilities
as relevant to the EP content.
• Outcomes of stakeholder consultation as relevant to the EP content.

In the event that new information is available, Shell will consider the new information in
accordance with the internal Management of Change processes (Section 10.1.9). The
EP knowledge base has a scheduled annual review and the review is planned for in the
Prelude FLNG Compliance Register (HSE_PRE_012227).

10.4.7 Management Review of EP

A review of the EP is to be done on an annual basis which will include review of the risk
ranking of environmental impacts, effectiveness of controls, relevant records required
as evidences of compliance, compliance issues and progress of any actions required to
address any compliance issues. The annual HSSE Management System Review
includes Environment and identifies areas of concern and improvement at a
management system level which outputs the following year’s HSSE Improvement Plan.

10.4.8 Management of Incidents and Non-Conformances

All Health, Safety, Security and Environmental incidents and non-conformances are
managed in accordance with the Shell Australia HSSE Incident Reporting, Investigation
and Follow up Procedure (HSE_GEN_000027) that describes the process of reporting,
classification, investigation, follow-up and close out. Non-conformances are treated in
the same way as incidents and for the purposes of this document are referred to as
incidents.
All incidents records are managed in an online electronic system called Fountain
Incident Management (FIM). Below is the overview of the incident management
process:
• The system allows incidents to be raised by any employee of the company including
offshore personnel.
• The incident is then assigned to a Responsible Supervisor (Incident Owner) who then
retains the ownership of the incident until closeout.
• The Responsible Supervisor initiates the Incident Investigation the depth of which
depends on the actual and potential risk ranking of the incident.
• The recommendations of the investigation team are reviewed by the Incident Owner
who then assigns the corrective and preventative actions to the appropriate action party.
Actions are tracked to closeout where the Incident Owner accepts that the remedial
action is successfully completed based on the evidence recorded and logged in FIM.
• FIM provides functionality for automatic reminders for Incident Owner and Action Parties
about the actions due. However, in addition reviews of outstanding actions are carried
out both at asset/department level, and at the Shell Business Assurance Committee
level at regular intervals to ensure timely closeout of actions.
All employees or contracted staff are encouraged to submit incident reports to alert the
organisation about the occurrence of an incident or non-conformance.

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In addition to the Incident Management Process outlined above, Shell also reports the
number of non-compliances (incidents/ non-conformance) to the Shell Group on a
quarterly basis, along with other HSE data in accordance with Shell Group
Performance Monitoring and Reporting (PMR) standard. This information is reviewed in
a dedicated HSE Business Performance Review where Shell Australia performance is
reviewed by the Shell Group.
The incident investigation process works to understand the cause of an incident and
the reason why a control/ mitigation measure has failed and to rectify the fault to
prevent recurrence and the reporting process works to track performance and allows
sharing of learnings. This process contributes to reducing the risks to ALARP and
Acceptable Levels.

10.5 Reporting

10.5.1 Annual Environmental Performance Reporting

Regulation 14(2) and 26C requires that an Environmental Performance report will be
submitted to NOPSEMA in intervals of not more than one year. Annual Environmental
Performance Reports will contain a full year (1 July – 30 June the following year) and
will be submitted to NOPSEMA by 31 December.
Shell is also required to report annual GHG emissions and energy usage and pollutants
emissions under the NGER Scheme and NPI reporting, respectively. The reporting
period for these also cover a full year (1 July – 30 June the following year).

10.5.2 External Incident Reporting

Reportable Incidents
NOPSEMA will be notified of all reportable incidents under Regulation 26 of the
OPGGS (E) Regulation within two hours of the incident and in writing within three days.
Under the OPGGS (E) Regulations, Reportable Incidents are defined as ‘an incident
relating to the activity that has caused, or has the potential to cause, moderate to
significant environmental damage’. The Shell Risk Assessment Matrix (refer to Section
9.2) uses severity levels 0 to 5 to define environmental consequences (no effect, slight
effect, minor effect, moderate effect, major effect and massive effect’). All
environmental effects with a severity 3 or greater (i.e. moderate to massive) are
considered Reportable Incidents. Based on the risk assessment (Table 9-32 and Table
9-82), five events are considered to be of moderate or higher consequence:
• Any confirmed introduced marine pest species in Australian waters attributable to the
petroleum activities
• Diesel spill resulting from a collision with another vessel
• HFO spill due to rupture of storage tank of a product offtake tanker
• Condensate spill due to rupture of storage tanks on the FLNG as a result of breach of
the hull
• An uncontrolled hydrocarbon release from the wellhead similar to a well blow-out.
The reportable incident report contains all material facts and circumstances concerning
the reportable incident, actions taken to avoid or mitigate any adverse impacts and
corrective action taken. This report will be submitted to NOPSEMA.
Recordable Incidents

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For the purpose of this activity, in accordance with the OPGGS (E) Regulations, a
recordable incident, for an activity, means ‘a breach of an environmental performance
outcome or environmental performance standard, in the environment plan that applies
to the activity, that is not a reportable incident’.
NOPSEMA will be notified of all Recordable Incidents, according to the requirements of
Regulation 26B of the OPGGS (E) Regulations. A report of Recordable Incidents must
be given to NOPSEMA ‘as soon as practicable after the end of each calendar month,
and in any case not later than 15 days after the end of the calendar month’.
As per the OPGGS (E) Regulations, the report will comprise:
• ‘A record of all Recordable Incidents that occurred during the calendar month
• All material facts and circumstances concerning the Recordable Incidents that the
operator knows or is able, by reasonable search or enquiry, to find out
• Any action taken to avoid or mitigate any adverse environment impacts of the
Recordable Incidents
• The corrective action that has been taken, or proposed to be taken, to prevent similar
Recordable Incidents’.
Other Externally Notifiable Incidents
Other externally notifiable incidents are captured in Table 10-13.
Table 10-13: Other Externally Notifiable Incidents

Timing of
Notification with
Incident Legislation respect to the Contact Details
occurrence of the
incident.

Any breach in the Biosecurity Act 2018, As soon as Department of Agriculture, Water
quarantine Australian Ballast practicable and the Environment (Maritime
regulations, including Water Management National Coordination Centre)
exchange of ballast Requirements 2017
water within the Phone: 1300 004 605
twelve nautical mile
limit.

Any confirmed Fish Resources Within 24 hours. DPIRD

introduced marine Management
pest species in Regulations 1995 FishWatch 1800 815 507
Western Australian r176(1) Email:
state waters. aquatic.biosecurity@dpird.wa.gov
.au
Aquatic Pest Biosecurity Section:
08 9203 0111

Death or injury of EPBC Act 1999, Within 7 days, The Secretary, DAWE
threatened, migratory Chapter 5, Part 13, including the time,
or cetacean species Division 3, subdivision place, circumstances,
from collision with a C, 232 (2) species affected and
vessel. the consequences of
the action.

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10.5.3 Internal Reporting

Shell has internal reporting requirements against environment parameters identified in
the Shell Group Performance Monitoring and Reporting (PMR) standard. This data is
used as the basis for an annual Shell Group Sustainability Report.

10.5.4 Notifications
In accordance with Regulation 19 of the OPGGS (E) Regulations, this EP remains valid
from NOPSEMA acceptance for a period of five years, or until NOPSEMA has
accepted an end-of- activity notification under Regulation 25A or Shell Australia revise
and resubmit this EP.

10.5.5 Details of Titleholder and Liaison Person

In accordance with Regulation 15 of the OPGGS (E) Regulations, details of the
titleholder, liaison person and arrangements for notifying of changes are described
below.
Titleholder:
Shell Australia Pty Ltd (can: 009663576/ABN: 14009663876)
562 Wellington Street, Perth 6000 WA

Activity Contact:
Peter Norman
Prelude FLNG Asset Manager
Email address: SDA-preludeflng@shell.com
Contact numbers: 1800 059 152
Should the titleholder, titleholder’s nominated liaison person or the contact details for
either change, NOPSEMA is to be notified in writing of the change within two weeks or
as soon as practicable.

10.6 Record Keeping

Compliance records will be maintained. Record keeping will be in accordance with
OPGGS (E) Regulation 14(7) that addresses maintaining quantitative records of
emissions and discharges which is accurate and can be monitored and audited against
the EPSs and MC.

10.7 Emergency Preparedness and Response

Under Regulations 14(8) the Implementation Strategy must contain an OPEP and
provide for the updating of the OPEP. Regulation 14(8AA) outlines the requirements for
the OPEP which must include adequate arrangements for responding to and
monitoring of oil pollution.
A summary of Shell Australia’s emergency and incident management framework and
arrangements are presented in Figure 10-14 and described in the following sections.

10.7.1 Shell HSSE & CP Control Framework

The Shell HSSE & SP Control Framework is a comprehensive corporate management
framework that applies to every Shell company, contractor and joint venture under

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Shell’s operational control. The framework contains a simplified set of mandatory

requirements that define high level HSSE & SP principles and expectations.
Emergency Response Management and Spill Preparedness and Response are two
areas covered in the Shell HSSE & SP Control Framework.

Figure 10-14: Shell Australia Emergency and Incident Management System Overview

10.7.2 Shell Australia Emergency Management Manual

The Shell Australia Emergency Management Manual (HSE_GEN_010996) provides a
tiered response framework which classifies incidents based on the level of resourcing
and support required. It also outlines communication arrangements associated with
each level of emergency, emergency response roster arrangements, emergency
response training and competencies, and requirements for emergency management
drills and exercises.

10.7.3 Incident Management Team (West) (IMT(W)) Emergency

Response Plan
The Incident Management Team (West) (IMT(W)) Emergency Response Plan
(HSE_GEN_011209) is a supporting document to the Shell HSSE & SP Control
Framework, Shell Australia Emergency Management Manual (HSE_GEN_010996) and
is consistent with Australian Commonwealth and State Emergency Management
Arrangements. The purpose of the IMT (W) Emergency Response Plan
(HSE_GEN_011209) is to provide specific assistance and guidance to Shell Australia
IMT (W) in support of Shell owned, operated or contracted facilities. The following
topics are detailed in the document:

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• Shell Australia emergency management arrangements;

• Shell Australia IMT(W) role checklists and duty cards;
• Incident management, action planning, ICS forms and briefing templates;
• IMT (W) communications;
• Guidance for responding to emergencies;
• Supporting subject matter expert units; and
• De-escalation and recovery.

10.7.4 Prelude Facility Emergency Response Plan

Prelude Facility Emergency Response Plan (HSE_PRE_005612) defines emergency
response arrangements for the Prelude FLNG, including detailed checklists for all
credible incidents, including well blow out and vessel collision. It describes the interface
arrangements between the IMT, CMT and ERT and provides roles and responsibilities
of personnel involved in the response.
Scenario-based drills are performed to test the emergency response arrangements and
updates are made to improve the ERP, if required.

10.7.5 Oil Pollution Emergency Plan

The Prelude OPEP (HSE_PRE_013075) outlines emergency management
arrangements to respond to credible spill scenarios associated with the Prelude
activity. The OPEP provides the information required for an effective response in the
unlikely event of an unplanned release of petroleum products. The OPEP details the
actions to be taken in response to the incident and provides contact details of
emergency specialist response groups, statutory authorities and other external bodies
requiring notification.

10.7.6 Operational and Scientific Monitoring Framework

Shell is required to have in place arrangements for monitoring oil pollution as part of its
OPEP. Shell is adopting use of the Joint Industry OSMP Framework (APPEA, 2020)
and its associated OMP’s and SMP’s to guide environmental monitoring that may be
implemented in the event of a Level/Tier 2-3 spill of hydrocarbons. Further information
on how the Joint Industry OSMP Framework interfaces with Shell’s activities, spill risks
and internal management systems is presented in Shell’s Operational and Scientific
Monitoring Bridging Implementation Plan (HSE_PRE_16370).

10.7.7 Shell Australia’s Emergency Management Structure

Shell Australia applies the Incident Command System (ICS) methodology for
emergency management. The ICS is a management system designed to enable
incident management through integrating facilities, equipment, personnel, procedures
and communications operating under one structure. An ICS is commonly structured
into functional areas that facilitate incident management activities, including operations,
planning, logistics, finance and incident command.
Shell Australia also applies a graduated response framework that increases resource
involvement based on the significance and escalation potential of the incident. This
graduated framework involves three key emergency management teams, as described
below:

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• Emergency Response Team (ERT) which is based on the facility and is responsible for
the initial response to the incident. The Facility Incident Commander (Offshore
Installation Manager (OIM)) will liaise closely with the IMT West Leader (onshore) and
will identify when additional support is required to respond to an incident
• Incident Management Team (West) (IMT(W)) is based onshore and supports the ERT,
by providing advice, logistical support and managing the operational and technical
aspects of the response; and
• Crisis Management Team (CMT) is based onshore and is responsible for the overall
management of the incident from a strategic, commercial, legal, reputational and high
level liaison perspective.
The ERT and IMT (W) are scalable to the nature and scale of the response i.e. one
person can take on multiple roles where circumstances permit. The mobilisation of the
ERT is at the directive of the Facility Incident Commander or delegate. The mobilisation
of the IMT (W) will occur by the Facility Incident Commander contacting the on-duty
IMT (W) Leader who will then mobilise the IMT (W) as the situation warrants. Duty
positions within IMT (W) area are staffed by a roster system where each position has
required personnel identified for the role. On-call positions within IMT (W) provide
specific functional expertise that helps the business respond to relevant incident
scenarios. On-call positions are activated as part of the IMT(W) at the discretion of the
IMT Leader based upon known or potential requirements. A number of people are
identified and trained for each on-call position, with a rotating on-call list used to
contact these personnel.
Figure 10-15 outlines the emergency management escalation process adopted by the
IMT (W) and the IMT (W) structure is shown in Figure 10-16.

Figure 10-15: Emergency Management Escalation Process Adopted by IMT (W)

Interface between the IMT and Crisis Management Team (CMT) is outlined in the Shell
Australia Weekly Contact List (HSE_GEN_011648). The affected facility business
executive will have been notified by the IMT (W) Leader and will in turn notify the Shell
Australia CMT leader.
In addition to these resources, Shell Australia can activate additional support through
the Shell Global Response Support Network (GRSN). The GRSN is a network of
emergency response trained Shell Staff employed in a wide range of positions within
Shell’s global and local businesses who have received specific training related to oil

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spill response and who may be called upon to support any business or country globally
which is responding to a large scale incident. Shell Australia also has access to the
Well Control Virtual Emergency Response Team (WCVERT), which provides virtual or
physical mobilisation of a wide range of technical expertise.
Shell Australia could also activate external additional resources for Level/Tier 2-3 spills
to fill various ERT and IMT roles for the duration of the response, if they were required.
This includes Oil Spill Response Organisation (OSRO) personnel and trained mutual
aid personnel (as per AMOSPlan), as outlined in Section 3.2 of the Prelude OPEP
(HSE_PRE_013075).

IMT (W) Leader *

External (G) Safety

Relations * Officer *

Legal Officer HR Officer

Operations Planning Logistics Finance

Section Chief * Section Chief * Section Chief * Section Chief

Document
Lead *

Situation
Lead *

Environment
Unit Lead

SME as req'd

*indicates duty roles, all other positions are on-call

Figure 10-16: Incident Management Team (West) (IMT (W)) Structure

The Source Control Branch (if required), falls under the Operations Section of the IMT
and develops and implements strategies and tactics to regain control of the well, and
stop or contain the discharge of hydrocarbons. This strategy includes:
• Development of solutions;
• Coordination of engineering safety and operational activities;
• Development of task-specific plans and procedures;
• Identification of required tools and equipment; and
• Monitoring progress in achieving well control.
The activities of the Source Control Branch in Australia will be organised into additional
groups, according to the specific requirements of the incident. These additional groups
may include a Capping and Subsea Intervention Group, Well Control Group and Offset
Installation Taskforce. All source control personnel complete ICS 100 and 200 training.

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10.7.8 Emergency Management Roles and Responsibilities

Shell Australia’s Incident Management Team (West) (IMT(W)) Emergency Response
Plan (HSE_GEN_011209) and Prelude Facility Emergency Response Plan
(HSE_PRE_005612) provide detailed guidance on roles and responsibilities for all
emergency management personnel.
A summary of key roles and responsibilities for Shell Australia personnel for incident
response are outlined in Table 10-14. Also provided are the roles and responsibilities of
Shell Australia personnel required to work within the WA Department of Transport
(DoT) organisational structure (Table 10-15), where DoT has responsibilities for spill
response as a Control Agency, as per DoT’s Offshore Petroleum Industry Guidance
Note – Marine Oil pollution: Response and Consultation Arrangements. DoT will
provide two roles to Shell’s IMT/CMT in a coordinated response. These roles and
responsibilities are provided in Table 10-16.
Table 10-14: Summary of Roles and Responsibilities of Key Emergency Management
Personnel
Key Roles Responsibilities

Maintain the safety of all Prelude personnel and initiates actions to protect the
environment and the Prelude asset
Ensure all first strike actions carried out as per OPEP
Facility
Control source of spill (if practicable)
Incident
Commander Classify the Level/Tier of spill
(OIM)
Notify and maintain regular communications with Incident Management Team Leader
(Offshore) (West) of incident
Verbally notify NOPSEMA (within 2 hours of spill) if spill is within Commonwealth
waters
Initiate monitor and evaluate activities, as per OPEP

Responsible for emergency scene coordination and safety of all personnel at the
On-scene emergency scene
Commander
Move ERT forward when authorised by Incident Commander (OIM)
(Offshore)
Provide regular situation updates to the Operations Section Chief on incident
progress against response plan priorities

Ensure all first strike actions carried out per OPEP

Activate IMT, if required
Conduct overall management of incident response operations
Assess the situation and confirm or adjust the spill classification Level/Tier in
IMT (W) consultation with the OIM and Operations Section Chief
Leader
Notify CMT Leader of event and initial response level
(Onshore)
Determine incident priorities and objectives for IMT
Confirm Incident Action Plan (IAP) is being developed, approve and authorise
implementation of IAPs
Confirm all external notifications and reporting have been made, as outlined in OPEP
Mobilise external support, if required, as per OPEP

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Key Roles Responsibilities

Oversees all operational resources and activities supporting an emergency

Establish communications with ERT
Provide overview of response operations at initial IMT brief
Communicate incident updates provided by the ERT to IMT through meetings and team
Operations
briefs
Section Chief
(OSC) Provide incident details to the Planning Section Chief and Situation Unit Lead for
development of Initial IAP and help develop incident objectives and strategies
(Onshore)
Determine operational areas e.g. staging areas, forward command, incident area,
oiled wildlife receiving and demobilisation areas
Executes IAPs for each operational period
Responsible for safety of all personnel involved in response

Facilitate all IMT meetings

Planning
Assist the IMT (W) Leader in development of incident objectives
Section Chief
(PSC) Facilitate development of IAP for next operational period
(Onshore) Mobilise Environment Unit
Monitor situation reports and update status displays with additional information and
adjust IAP as necessary

Source all logistical requirements to complete response operations, including

personnel, equipment and supplies for ongoing incidents
Logistic Liaise with Planning Section Chief on specialist resource requirements being
Section Chief considered in response strategies. Verify availability as this may affect strategy
(LSC) selection
(Onshore) Where required incident resources are not immediately available through existing
contracts, liaise with Contracts & Procurement to develop contractual arrangements
as required

Conduct relevant external notifications, as outlined in OPEP

Environment Review OMP initiation criteria and activate OSMP contractor where required
Unit Lead Confirm protection priorities
(EUL)
Validate strategic SIMA and generate the initial operational SIMA
(Onshore)
Provide guidance to the OSC on environmental management measures to be
followed during response operations.

Develops and implements strategies and tactics to regain control of the well, and stop
or contain the discharge of hydrocarbons. This strategy includes:
• the development of task-specific plans and procedures

Source Control • the identification of required tools and equipment

Branch • monitoring progress in achieving well control
Director
Assign a person or persons to liaise with the SIMOPS unit (if assigned) under the
Operations Section, which is overall in charge of simultaneous operations and
maintenance of the Common Operating Picture
Activate specialist Source Control Groups as required

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Key Roles Responsibilities

Responsible for collecting, processing and organising incident information relating to

the growth, mitigation or intelligence activities taking place on the incident
Manages all situational awareness and intelligence information relating to the
Situation Unit
incident, including geospatial/meteorological information
Lead
Ensure status boards updated, retain clear records of out of date vs current
(Onshore)
information
Prepare and disseminate resource and situation status information as required,
including special requests.

Responsible for the maintenance of accurate, up-to-date incident files i.e. IAP,
incident reports, communications logs
Documentation
Unit Lead Compiles and collates all unit logs, communications and other records so that a
consolidated set of incident documentation is maintained.
(Onshore)
Liaise with the Situation Unit Lead to collate and store all relevant documentation
produced for Situation Updates

External Conduct relevant external notifications, as outlined in OPEP

(Government) Manages all external communications until CMT assumes responsibility
Relations/
Public Evaluate the need for a joint information communication centre
Information Ensure active and ongoing engagement with all relevant stakeholders and external
Officer (PIO) response agencies. Prepare stakeholder management plan for approval by IMT
(Onshore) Develop material for use in media releases

Conduct hazard assessment and advise OIM of recommended safety actions and
safe approach routes
Safety Officer
Assist the OSC and LSC by facilitating risk assessments during event response and
(Onshore) recovery plan development as required
Review IAPs for safety implications

Finance The Finance (& Admin) Section Chief is responsible for all financial, administrative
Section Chief and cost analysis aspects of an emergency
(Onshore) Provide financial and cost analysis information as requested

Table 10-15: Shell Personnel Roles Positioned within the State Maritime Environmental
Emergency Coordination Centre (MEECC)/ DOT IMT
Key Roles Responsibilities

CST Liaison Provide a direct liaison between the Shell and the State MEECC
Officer Facilitate effective communications and coordination between the Shell CMT Leader
and the State Maritime Environmental Emergency Coordinator (SMEEC)
Offer advice to SMEEC on matters pertaining to Shell crisis management policies
and procedures

Deputy Provide a direct liaison between the DoT IMT and the Shell IMT
Incident Facilitate effective communications and coordination between the Shell IMT (W)
Officer Leader and the DoT Incident Controller
Offer advice to the DoT Incident Controller on matters pertaining to the Shell incident
response policies and procedures

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Key Roles Responsibilities

Offer advice to the Safety Coordinator on matters pertaining to Shell safety policies
and procedures particularly as they relate to Shell employees or contractors
operating under the control of the DoT IMT

Intelligence As part of the Intelligence Team, assist the Intelligence Officer in the performance of
Support their duties in relation to situation and awareness
Officer Facilitate the provision of relevant modelling and predications from the Shell IMT
Assist in the interpretation of modelling and predictions originating from the Shell
IMT
Facilitate the provision of relevant situation and awareness information originating
from the DoT IMT to the Shell IMT
Facilitate the provision of relevant mapping from the Shell IMT
Assist in the interpretation of mapping originating from the Shell IMT
Facilitate the provision of relevant mapping originating from the Shell IMT

Deputy As part of the Planning Team, assist the Planning Officer in the performance of their
Planning duties in relation to the interpretation of existing response plans and the development
Officer of incident action plans and related sub plans
Facilitate the provision of relevant IAP and sub plans from the Shell IMT
Assist in the interpretation of the Shell OPEP from Shell
Assist in the interpretation of the Shell IAP and sub plans from the Shell IMT
Facilitate the provision of relevant IAP and sub plans originating from the DoT IMT
to the Shell IMT
Assist in the interpretation of Shell’s existing resource plans
Facilitate the provision of relevant components of the resource sub plan originating
from the DoT IMT to the Shell IMT
(Note this individual must have intimate knowledge of the relevant Shell OPEP and
planning processes)

Environmental As part of the Planning Team, assist the Environmental Officer in the performance
Support of their duties in relation to the provision of environmental support into the planning
Officer process
Assist in the interpretation of the Shell OPEP and relevant TRP plans
Facilitate in requesting, obtaining and interpreting environmental monitoring data
originating from the Shell IMT
Facilitate the provision of relevant environmental information and advice originating
from the DoT IMT to the Shell IMT

Public As part of the Public Information Team, provide a direct liaison between the Shell
Information Media team and DoT IMT Media team
Support & Facilitate effective communications and coordination between Shell and DoT media
Media Liaison teams
Officer
Assist in the release of joint media statements and conduct of joint media briefings
Assist in the release of joint information and warnings through the DoT Information
& Warnings team
Offer advice to the DoT Media Coordinator on matters pertaining to Shell media
policies and procedures
Facilitate effective communications and coordination between Shell and DoT
Community Liaison teams
Assist in the conduct of joint community briefings and events
Offer advice to the DoT Community Liaison Coordinator on matters pertaining to
Shell community liaison policies and procedures

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Key Roles Responsibilities

Facilitate the effective transfer of relevant information obtained from through the
Contact Centre to the Shell IMT

Deputy As part of the Logistics Team, assist the Logistics Officer in the performance of their
Logistics duties in relation to the provision of supplies to sustain the response effort
Officer Facilitate the acquisition of appropriate supplies through Shell’s existing OSRL,
AMOSC and private contract arrangements
Collects Request Forms from DoT to action via the Shell IMT
(Note this individual must have intimate knowledge of the relevant Shell logistics
processes and contracts)

Deputy As part of the Operations Team, assist the Operations Officer in the performance of
Operations their duties in relation to the implementation and management of operational
Officer activities undertaken to resolve an incident
Facilitate effective communications and coordination between the Shell Operations
Section and the DoT Operations Section
Offer advice to the DoT Operations Officer on matters pertaining to Shell incident
response procedures and requirements
Identify efficiencies and assist to resolve potential conflicts around resource
allocation and simultaneous operations of Shell and DoT response efforts

Deputy Waste As part of the Operations Team, assist the Waste Management Coordinator in the
Management performance of their duties in relation to the provision of the management and
Coordinator disposal of waste collected in State waters
Facilitate the disposal of waste through Shell’s existing private contract
arrangements related to waste management and in line with legislative and
regulatory requirements
Collects Waste Collection Request Forms from DoT to action via the Shell IMT

Deputy As part of the Finance Team, assist the Finance Officer in the performance of their
Finance duties in relation to the setting up and payment of accounts for those services
Officer acquired through Shell’s existing OSRL, AMOSC and private contract arrangements
Facilitate the communication of financial monitoring information to the Shell to allow
them to track the overall cost of the response
Assist the Finance Officer in the tracking of financial commitments through the
response, including the supply contracts commissioned directly by DoT and to be
charged back to Shell

Deputy On As part of the Field Operations Team, assist the On Scene Commander in the
Scene performance of their duties in relation to the oversight and coordination of field
Commander operational activities undertaken in line with the IMT Operations Section’s direction
(FOB) Provide a direct liaison between Shell’s Forward Operations Base/s (FOB/s) and the
DoT FOB
Facilitate effective communications and coordination between Shell On Scene
Commander and the DoT On Scene Commander
Offer advice to the DoT On Scene Commander on matters pertaining to Shell
incident response policies and procedures
Assist the Safety Coordinator deployed in the FOB in the performance of their duties,
particularly as they relate to Shell employees or contractors
Offer advice to the Safety Coordinator deployed in the FOB on matters pertaining to
Shell safety policies and procedures

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Table 10-16: Roles and Responsibilities of DoT Personnel to be Positioned in Shell’s

IMT/CMT
Key Roles Responsibilities

Facilitate effective communications between DoT’s SMEEC and Incident Controller

and Shell’s appointed CMT Leader and Incident Controller
Provide enhanced situational awareness to DoT of the incident and the potential
DoT Liaison impact on State waters
Officer
Assist in the provision of support from DoT to Shell
Facilitate the provision technical advice from DoT to Shell’s Incident Controller as
required

Provide a direct liaison between Shell’s Media team and DoT IMT Media team
Facilitate effective communications and coordination between Shell and DoT media
teams
Media Liaison
Officer Assist in the release of joint media statements and conduct of joint media briefings
Assist in the release of joint information and warnings through the DoT Information
and Warnings team
Offer advice to the Shell Media Coordinator on matters pertaining to DoT and wider
Government media policies and procedures

10.7.9 Emergency Management Exercises, Training and

Competencies
Shell Australia follows the approved ICS and IMO emergency management training
requirement for ICS command and general staff. Specific competencies for IMT
members are defined in the Shell Operational HSSE Competence Framework and are
tracked in the Shell Open University. A summary of training requirements and core
competencies for Shell key ERT, IMT and CMT personnel are outlined in Table 10-17.
Only persons that have completed all mandatory training requirements can be placed
on the IMT roster. Training status of IMT personnel is reviewed monthly (or following
significant personnel or policy change by the SA Emergency Response Coordinator)
and notifications issued in advance to personnel requiring re-validation by training
and/or emergency response exercise participation.
Oil spill responder training requirements are outlined in Table 10-18.
Table 10-17: Exercise and Training Requirements for Key ERT, IMT and CMT Personnel
Key Roles Exercises Training

ERT Personnel Weekly muster alarm drill (may be Some offshore roles may have
combined with Level/Tier 1 exercise) AMOSC - IMO training.
OIM
1 x Level/Tier 1 exercise per swing
Level/Tier 2/3 exercise 6 monthly in
accordance with 3 year exercise plan.

IMT Personnel It is required that 80% of personnel All IMT personnel complete ICS 100,
will participate in an IMT exercise 200 and IMT induction.
IMT (W) Leader annually.
IMT (W) leader undertakes - IMO3 Oil
Spill Command & Control

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Key Roles Exercises Training

Operations Section It is a target that 80% of personnel AMOSC – IMO2 Oil Spill
Chief (OSC) will participate in an IMT exercise Management
annually.
Planning Section
Chief (PSC) Participation in exercises is tracked in
the Shell Australia Exercises &
Logistic Section Chief Training Schedule and is reviewed
(LSC) monthly or following significant
Environment Unit personnel or policy change by the
Lead (EUL) Shell Australia Emergency Response
Coordinator.

CMT Personnel Level/Tier 2/3 exercise on a biennial Shell specific – Group Crisis training
basis

Table 10-18: Oil Spill Responder Training and Resources

Key Roles Exercises/Training Available Resources

Shell AMOSC Core AMOSC Core Group Workshop As defined in AMOSC contractual
Group members (refresher training undertaken every 2 core group requirements
years) Operations stream and
management stream

Prelude FLNG ERT Training as per Prelude Asset 1 per swing

Personnel Training Strategy and Competence
Management Plan
(HRS_PRE_004622)
Weekly muster alarm drill (may be
combined with Level/Tier 1 exercise)
1 x Level/Tier 1 exercise per swing
Level/Tier 2/3 exercise according to 3
year exercise plan (6 monthly).
Level/Tier 2 and 3 exercises are
planned and scheduled as per the
Prelude Operations Desktop (ODT)
portal.
AMOSC Core Group
Responders AMOSC Core Group Workshop As defined in AMOSC contractual
(refresher training undertaken every 2 core group requirements
years)

OSRL Oil Spill As per OSRL training and As defined in OSRL Service Level
Response Personnel competency matrix Agreement

AMOSC Oil Spill As per AMOSC training and As defined in AMOSC Master
Response Specialists competency matrix Services Agreement

Operational and As defined in the Shell Australia As per Standby Capability and
Scientific Monitoring Operational and Scientific Monitoring Competency Report
Service Providers (OSM) Bridging Implementation Plan
(HSE_PRE_16370).

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Key Roles Exercises/Training Available Resources

Oiled Wildlife As per DBCA OWR requirements As per OWR stateboard (AMOSC &
Responders (Level 2- (WA OWRRP) DBCA)
4)
As defined in AMOSC Master
Shoreline clean-up Services and OSRL Service Level
personnel As per WA DoT requirements Agreements.
Team members available through
labour hire contracts (training
provided prior to deployment)

Shell Australia maintains an Exercise and Training Schedule as detailed in the Shell
Australia Emergency Management Manual (HSE_GEN_010996) to ensure its
competency in responding to and managing major incidents, including oil spills. The
Exercise and Training Schedule is reviewed and revised (if required) annually.
As part of this schedule, Shell conducts a number of different exercise types, which are
further described in Table 10-19.
Table 10-19: Exercise Types, Objectives and Frequency
Exercise Type Objective Frequency

Notification exercise To test all communication and At least annually

notification processes to service
providers and regulatory agencies When OPEP is accepted or
defined within the OPEP introduced
When response arrangements have
been significantly amended
If a new location for the activity is
added after the response
arrangements have been tested

Equipment To focus on Shell’s deployment Level /Tier 1 – Annually

deployment exercises capability
Level/Tier 2 – Every 2 years
To inspect and maintain the condition
of Shell’s oil spill response equipment
To maintain training of field response
personnel

Tabletop exercise To encourage interactive discussions As per Shell Australia’s Exercise and
of a simulated scenario amongst IMT Training Schedule
members and refresh roles and
responsibilities

Incident Management To activate IMT and establish Minimum of one oil spill exercise per
Exercise command, control, and coordination year for Shell Australia’s activities.
of a simulated Level/Tier 2 or 3 Where response arrangements are
incident and test response the same for a number of activity-
arrangements in OPEP specific OPEPs, one exercise may be
used to test these response
arrangements for these OPEPs at the
same time

National Plan Participate as required to ensure As determined by AMSA and/or WA

Exercises or WA DoT alignment between National/State DoT, Shell may not be requested to
exercises participate every year

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Exercise Type Objective Frequency

Response Framework and Shell
Australia’s Response Framework

Shell Global Test the functionality of Shell’s Annually

Response Support Regional Core Group Level/Tier 3 oil
Network (GRSN) spill response capabilities
Target of 100% for participation of Every 2 years
Shell Australia’s Core Group
personnel in GRSN regional
exercises as required.

AMOSC Audit To test deployment readiness and Annually

capability of AMOSC as per its
Master Services Agreement with
Shell

OSRL Audit To test deployment readiness and Every 2 years

capability of OSRL in Singapore as
per OSRLs Service Level Agreement
with Shell

As part of the exercise process, a number of documents are prepared to ensure

exercises are well planned, conducted and evaluated. To support this, the following
documents are used:
• Exercise scope document – provides background context to the exercise, outlines the
exercise need, aim, objectives, details of the scenario, participating groups and
agencies, exercise deliverables and management structure. This document can be
used to engage a third-party contractor to assist in conducting the exercise
• Exercise plan and instructions – provide instructions and ‘play’ (including any injects) for
conducting the exercise
• Post exercise report – includes an after-action review of the exercise, evaluating how
the exercise performed against meeting its aim and objectives.

10.7.10 Mechanism to examine the effectiveness of the response

arrangements
Shell Australia routinely undertakes post-exercise debriefings following Level/Tier 2-3
OPEP exercises to evaluate effectiveness of response arrangements against the
exercise objective/s, identify opportunities for improvement and communicate lessons
learned. Shell sets Specific, Measurable, Achievable, Realistic and Timely (SMART)
objectives for oil spill exercises so that they can be clearly evaluated as being met or
not.
An independent assessor (either internal or external) will examine the effectiveness of
the response arrangements during a spill exercise. The assessor will make written
findings and recommendations from the test for consideration by Shell to assist in
identifying deficiencies with response arrangements and continually improve the overall
response readiness of Shell.
Recommendations from the tests will have SMART actions put against them where
appropriate and they will be tracked to closure in Shell’s Action Tracking System,
Fountain Incident Management (FIM). The FIM system assigns a responsible person
and due date against each action to ensure they are tracked to closure.

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Assurance of Shell Group Response Arrangements

The major advantage of the GRSN/WCVERT is the ability to leverage the resources
and support from the Shell Group for a local operations team, which may have a
reasonably small footprint, in the event of an incident. However, it is recognised and
must be made clear that during an incident the accountability for the response remains
with the local organisation, in this case Shell Australia. It is therefore a requirement that
the local organisation has the ability to test, evaluate and assure the capability of the
Shell GRSN and WCVERT to meet their response needs on an ongoing basis.
The GRSN and WCVERT partake in frequent exercises around the world to ensure a
state of readiness; these may be validated by local operating units as follows.
• upon request the GRSN/ WCVERT will share an updated drill schedule for forthcoming
global drills in which they will partake;
• where practicable and under instruction from Shell Australia GM Wells some of the
Shell Australia Source Control team may attend such drills to enhance training and
validate response capability; or
• where practicable reports from previously conducted drills including learnings may be
requested by Shell Australia to validate GRSN/ WCVERT response capabilities.
In order to monitor and track the availability of personnel, the WCVERT simulates
regular call out drills. This involves sending a group communication to the WCVERT
Source Control Branch members and recording the response, availability and response
time.
• As required, a local operating unit may request from the Well Control PTE an overview
of the recent call out drills to validate response capabilities.

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Environmental Impact Statement. Woodside Energy Ltd, Perth, WA.
Woodside Energy Limited (Woodside). 2011. Browse LNG Development, Draft
Upstream Environmental Impact Statement, EPBC Referral 2008/4111, November
2011.
Woodside Energy Limited (Woodside). 2013. Woodside Browse Floating Liquefied
Natural Gas (FLNG) Development, Offshore Western Australia, EPBC Referral
2013/7079, December 2013.

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12.0 Disclaimer
This document contains data and analysis from Shell’s Sky scenario. Unlike Shell’s previously published Mountains and
Oceans exploratory scenarios, the Sky scenario is based on the assumption that society reaches the Paris Agreement’s
goal of holding the rise in global average temperatures this century to well below two degrees Celsius (2°C) above pre-
industrial levels. Unlike Shell’s Mountains and Oceans scenarios, which unfolded in an open-ended way based upon
plausible assumptions and quantifications, the Sky scenario was specifically designed to reach the Paris Agreement’s
goal in a technically possible manner. These scenarios are a part of an ongoing process used in Shell for over 40 years
to challenge executives’ perspectives on the future business environment. They are designed to stretch management to
consider even events that may only be remotely possible. Scenarios, therefore, are not intended to be predictions of likely
future events or outcomes.
Additionally, it is important to note that as of 5 January 2021, Shell’s operating plans and budgets do not reflect Shell’s
net-zero emissions ambition. Shell’s aim is that, in the future, its operating plans and budgets will change to reflect this
movement towards its new net-zero emissions ambition. However, these plans and budgets need to be in step with the
movement towards a net-zero emissions economy within society and among Shell’s customers.
Also, in this document we may refer to “Shell’s Net Carbon Footprint”, which includes Shell’s carbon emissions from the
production of our energy products, our suppliers’ carbon emissions in supplying energy for that production and our
customers’ carbon emissions associated with their use of the energy products we sell. Shell only controls its own
emissions but, to support society in achieving the Paris Agreement goals, we aim to help and influence such suppliers
and consumers to likewise lower their emissions. The use of the terminology “Shell’s Net Carbon Footprint” is for
convenience only and not intended to suggest these emissions are those of Shell or its subsidiaries.
The companies in which Royal Dutch Shell plc directly and indirectly owns investments are separate legal entities. In this
documenton “Shell”, “Shell group” and “Royal Dutch Shell” are sometimes used for convenience where references are
made to Royal Dutch Shell plc and its subsidiaries in general. Likewise, the words “we”, “us” and “our” are also used to
refer to Royal Dutch Shell plc and its subsidiaries in general or to those who work for them. These terms are also used
where no useful purpose is served by identifying the particular entity or entities. ‘‘Subsidiaries’’, “Shell subsidiaries” and
“Shell companies” as used in this document refer to entities over which Royal Dutch Shell plc either directly or indirectly
has control. Entities and unincorporated arrangements over which Shell has joint control are generally referred to as “joint
ventures” and “joint operations”, respectively. Entities over which Shell has significant influence but neither control nor
joint control are referred to as “associates”. The term “Shell interest” is used for convenience to indicate the direct and/or
indirect ownership interest held by Shell in an entity or unincorporated joint arrangement, after exclusion of all third-party
interest.
This document contains forward-looking statements (within the meaning of the U.S. Private Securities Litigation Reform
Act of 1995) concerning the financial condition, results of operations and businesses of Royal Dutch Shell. All statements
other than statements of historical fact are, or may be deemed to be, forward-looking statements. Forward-looking
statements are statements of future expectations that are based on management’s current expectations and assumptions
and involve known and unknown risks and uncertainties that could cause actual results, performance or events to differ
materially from those expressed or implied in these statements. Forward-looking statements include, among other things,
statements concerning the potential exposure of Royal Dutch Shell to market risks and statements expressing
management’s expectations, beliefs, estimates, forecasts, projections and assumptions. These forward-looking
statements are identified by their use of terms and phrases such as “aim”, “ambition’, ‘‘anticipate’’, ‘‘believe’’, ‘‘could’’,
‘‘estimate’’, ‘‘expect’’, ‘‘goals’’, ‘‘intend’’, ‘‘may’’, ‘‘objectives’’, ‘‘outlook’’, ‘‘plan’’, ‘‘probably’’, ‘‘project’’, ‘‘risks’’, “schedule”,
‘‘seek’’, ‘‘should’’, ‘‘target’’, ‘‘will’’ and similar terms and phrases. There are a number of factors that could affect the future
operations of Royal Dutch Shell and could cause those results to differ materially from those expressed in the forward-
looking statements included in this document, including (without limitation): (a) price fluctuations in crude oil and natural
gas; (b) changes in demand for Shell’s products; (c) currency fluctuations; (d) drilling and production results; (e) reserves
estimates; (f) loss of market share and industry competition; (g) environmental and physical risks; (h) risks associated
with the identification of suitable potential acquisition properties and targets, and successful negotiation and completion
of such transactions; (i) the risk of doing business in developing countries and countries subject to international sanctions;
(j) legislative, fiscal and regulatory developments including regulatory measures addressing climate change; (k) economic
and financial market conditions in various countries and regions; (l) political risks, including the risks of expropriation and
renegotiation of the terms of contracts with governmental entities, delays or advancements in the approval of projects and
delays in the reimbursement for shared costs; (m) risks associated with the impact of pandemics, such as the COVID-19
(coronavirus) outbreak; and (n) changes in trading conditions. No assurance is provided that future dividend payments
will match or exceed previous dividend payments. All forward-looking statements contained in this document are
expressly qualified in their entirety by the cautionary statements contained or referred to in this section. Readers should
not place undue reliance on forward-looking statements. Additional risk factors that may affect future results are contained
in Royal Dutch Shell’s Form 20-F for the year ended December 31, 2019 (available at www.shell.com/investor and
www.sec.gov ). These risk factors also expressly qualify all forward-looking statements contained in this document and
should be considered by the reader. Each forward-looking statement speaks only as of the date of this document, 5
January 2021. Neither Royal Dutch Shell plc nor any of its subsidiaries undertake any obligation to publicly update or
revise any forward-looking statement as a result of new information, future events or other information. In light of these
risks, results could differ materially from those stated, implied or inferred from the forward-looking statements contained
in this document.
We may have used certain terms, such as resources, in this document that the United States Securities and Exchange
Commission (SEC) strictly prohibits us from including in our filings with the SEC. Investors are urged to consider closely
the disclosure in our Form 20-F, File No 1-32575, available on the SEC website www.sec.gov.

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List of Acronyms

Acronym Definition
AFMA Australian Fisheries Management Authority
AFZ Australian Fishing Zone
AHO Australian Hydrographic Office
AHTS Anchor Handling Tug Supply Vessel
AIS Automatic Identification System
ALARP As low as reasonably practicable
AMOSC Australian Marine Oil Spill Centre
AMP Australian Marine Park
AMSA Australian Maritime Safety Authority
ANZECC Australian and New Zealand Environment Conservation Council
APPEA Australian Petroleum Production & Exploration Association Limited
ASV Accommodation Support Vessel
AusSAR Australian Search and Rescue
BAT Best Available Technology
Bbl Barrels
BIAs Biologically Important Areas
BOD Biological oxygen demand
BOP Blowout Preventer
BTEX Benzene, toluene, ethylbenzene, xylenes
BTU British Thermal Unit
CAMBA China-Australia Bilateral Agreement on the Protection of Migratory
Birds
CHARM Chemical Hazard Management Risk Management
CMT Crisis Management Team
CO Carbon monoxide
CO2 Carbon dioxide
COLREGS International Regulations for Preventing Collisions at Sea 1972
CSIRO Commonwealth Scientific and Industrial Research Organisation
CTA Cable Termination Assembly
CW Cooling Water
DAFF Department of Agriculture, Fisheries and Forestry (now known as
the Department of Agriculture, Water and the Environment)
DAWE Department of Agriculture, Water and the Environment (represents
the former Department of Agriculture and Department of
Environment and Energy)
DoEE Department of Environment and Energy (now known as the
Department of Agriculture, Water and the Environment)
dB Decibels

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DBCA Department of Biodiversity, Conservation and Attractions (WA)

DC Drill centre
DEWHA Department of Environment Water Heritage and Arts (formally
DEH, Department of Environment and Heritage)
DMIRS Department of Mines, Industry Regulation and Safety (WA)
DMR Double mixed refrigerant
DP Dynamic positioning
DPIRD Department of Primary Industries and Regional Development (WA)
DSEWPaC Department of Sustainability, Environment, Water, Population and
Communities
DVA Direct vertical access
EAAF East Asian-Australasian Flyway
ECE Environmentally Critical Elements
ECU Electrochlorination Unit
EDG Emergency Diesel Generators
EEZ Exclusive economic zone
EGR External and Government Relations
EIS Environmental Impact Statement
ENVID Environmental Risk Identification
EP Environment Plan
EPO Environmental Performance Outcome
EPS Environmental Performance Standard
EPBC Act Commonwealth Environment Protection and Biodiversity
Conservation Act 1999
ERP Emergency Response Plan
ERT Emergency Response Team
ESD Ecological Sustainable Development
EUL Environment Unit Lead
FID Final Investment Decision
FIM Fountain Incident Management
FLNG Floating Liquefied Natural Gas
FO Fibre optic
FRC Fast rescue craft
FWAD Fixed Wing Aerial Dispersant
GHG Greenhouse gas
HEMP Hazards and Effects Management Process
HFO Heavy Fuel Oil
HLIV Heavy Lift Installation Vessel
HOCNF Harmonized Offshore Chemical Notification Format
HSE Health, Safety and Environment

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HSSE and SP Health, Security, Safety, Environment and Social Performance

ICS Incident Command System
IFC International Finance Corporation
IFO Intermediate Fuel Oil
IOPP International Oil Pollution Prevention
IMO International Maritime Organisation
IMR Inspection, Maintenance and Repair
IMS Invasive Marine Species
IMT (W) Incident Management Team West
IPEICA The International Petroleum Industry Environmental Conservation
Association
ISPP International Sewage Pollution Prevention
ISVs Infield Support Vessels
ITF Indonesian Throughflow
IUCN International Union for the Conservation of Nature
JAMBA Japan-Australia Bilateral Agreement on the Protection of Migratory
Birds
KEFs Key Ecological Features
LNG Liquefied Natural Gas
LOC Loss of containment
LOWC Loss of well containment
LPG Liquefied Petroleum Gas
LQ Living quarters
LWI Light well intervention
MAE Major Accident Events
MARPOL The International Convention for the Prevention of Pollution from
Ships, adopted by the International Conference on Marine
Pollution, convened by IMO, 1973/78.
MBP Mixed bed polisher
MC Measurement criteria
MEG Mono-ethylene Glycol
MFO Marine fauna observer
MGC Marine growth covers
MHWS Mean High Water Spring
MLWS Mean Low Water Spring
MNES Matters of National Environmental Significance
MoC Management of Change
MODU Mobile Offshore Drilling Unit
MOPO Manual Of Permitted Operations
MOU Memorandum of Understanding

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MPPE Macro Porous Polymer Extraction

MPV Multi-Purpose Vessel
MS Management System
MSL Mean Sea Level
MW Mega watt
NEPM National Environment Protection Measures
NGO Non-Government Organisations
Nm Nautical mile
NMR North Marine Region
NOPSEMA National Offshore Petroleum Safety and Environmental
Management Authority
NORM Naturally Occurring Radioactive Materials
NOx Nitrogen oxides, typically expressed as NO2
NPI National Pollutant Inventory
NT Northern Territory
NT DENR Northern Territory Department of Environment and Natural
Resources
NT DIPL Northern Territory Department of Infrastructure, Planning and
Logistics
NWMR North West Marine Region
NWS North West Shelf
OCNS Offshore Chemicals Notification Scheme
ODS Ozone depleting substances
OGP Oil and Gas Producers
OIE Offset Installation Equipment
OIM Offshore Installation Manager
OPEP Oil Pollution Emergency Plan
OPGGS (E) Offshore Petroleum and Greenhouse Gas Storage (Environment)
Regulations Regulations 2009
OPGGS Act Offshore Petroleum and Greenhouse Gas Storage Act 2006
OPRC 90 International Convention on Oil Pollution Preparedness, Response
and Cooperation 1990
OSMP Operational and Scientific Monitoring Plan
OSPAR Oslo and Paris Conventions for the protection of the marine
environment of the North-East Atlantic
OWR Oiled Wildlife Response
PAH Polycyclic Aromatic Hydrocarbon
PFW Produced Formation Water
PLET Pipeline End Termination
PLONOR Poses Little or No Risk
PM Particulate matter

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PMR Pre-cool mixed refrigerant

PMST Protected Matters Search Tool ( EPBC Act)
PNEC Predicted no effect concentration
POB Persons on Board
POP Persistent Organic Pollutant
PPM Parts per million
PPT Parts per trillion
PSV Platform Supply Vessel
PSZ Petroleum Safety Zone
PTS Permanent threshold shift
PTW Permit to work
PW Produced Water
RAM Risk Assessment Matrix
RBM Riser Base Manifold
RFSU Ready for Start-Up
RIH Run in hole
ROV Remotely Operated Vehicle
ROKAMBA The Republic of Korea Migratory Birds Agreement
SCAT Shoreline clean up assessment technique
SCE Safety Critical Elements
SCM Subsea control module
SCSSV Surface Controlled Sub-Surface Safety Valve
Shell Shell Australia Pty Ltd
SEWPAC Department of Sustainability, Environment, Water, Population and
Communities
SFRT Subsea First Response Toolkit
SG Specific gravity
SGG Synthetic greenhouse gases
SID Subsea Intervention Device
SIRT Subsea Incident Response Toolkit
SIMA Spill impact mitigation assessment
SIMOPs Simultaneous Operations
SOLAS International Convention for the Safety of Life at Sea 1974
SOPEP Shipboard Oil Pollution Emergency Plan
SO2 Sulphur dioxide
SSD Species Sensitivity Distribution
SSDI Subsea dispersant injection
SURU Start-up Ramp-up
TACL Threshold Activity Concentration Limits
TEC Threatened Ecological Communities

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tpa Tonnes per annum

tpd Tonnes per day
TMS Turret Mooring System
TOC Total Organic Carbon
TPH Total Petroleum Hydrocarbons
TTS Temporary Threshold Shift
UTA Umbilical termination assemblies
VOC Volatile Organic Compounds
WA Western Australia
WA DoT Western Australia Department of Transport
WB World Bank
WCVERT Well Control Virtual Emergency Response Team
WET Whole Effluent Toxicity
WHA World Heritage Area
WOMP Well Operations Management Plan
WRFM Well, Reservoir and Facility Management (WRFM)
XT Xmas tree for wellheads
ZPI Zone of potential impact

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13.0 Appendix A: Detailed Facility Description

13.1 Gas Process Facilities
Feed from the turret enters feed gas receiving and condensate stabilisation (Unit
10000). The gas, condensate and water phases are separated in two trains of inlet HP
separators and one low pressure separator. The aqueous phase is routed for
processing either in MEG regeneration (Unit 52000) or water treatment (Unit 64000).
The separated field condensate is stabilized in the condensate stabilizer and sent to
condensate storage (Unit 33000). The separated gas is routed to the Acid Gas
Removal Unit (AGRU, Unit 11000). The feed gas receiving unit is also provided with
depletion compression facility to compress the inlet gas once the reservoir pressure is
reduced.

Figure 13-1: FLNG Process Unit Block Diagram

The AGRU removes the acid gases (CO2, traces of H2S and mercaptans) from the feed
gas by contact with a lean amine based solvent stream. The resulting rich amine is
then regenerated and the separated CO2 rich acid gas stream is routed for safe
venting. The sweet gas passes through the dehydration (Unit 13000) unit for removal of
moisture and mercury removal (Unit 13500) unit for removal of mercury. The sweet, dry
and impurity free gas then enters Unit 14000 consists of NGL extraction, liquefaction
and end flash.
Natural Gas Liquid (NGL) within the feed gas stream is separated in the NGL extraction
column. The separated NGL is routed to Unit 15000, fractionation, and the natural gas
is sent to the liquefaction section of Unit 14000. The natural gas is pre-cooled and then
liquefied using closed loops of pre-cooled mixed refrigerant (PMR) and mixed
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refrigerant (MR). The produced LNG is let down to close to atmospheric pressure in a
turbo expander, before being routed to an end flash column. The resulting atmospheric
LNG stream is gravity rundown to storage in Unit 31000 and the end-flash gas
produced is compressed for use as fuel gas (Unit 44000).
Within the fractionation Unit 15000, the NGL is separated into ethane, propane, butane
and condensate streams. The ethane stream is either: re-injected into the liquefaction
unit, routed as vapour for use as fuel gas, or stored in refrigerant storage tank in Unit
16000 as a make-up to the refrigerant loop. Commercial grade propane and butane are
produced and routed to LPG storage in Unit 32000. Provision is made to re-inject LPG
to liquefaction unit as required. Pure Propane is stored in dedicated refrigerant storage
tank in Unit 16000 as a make-up to the refrigerant loop. The plant condensate stream
produced from the fractionation unit (U15000) is combined with the field condensate
from Unit 10000 and routed to condensate storage Unit 33000. LNG and LPG products
are offloaded to ship tankers by side by side offloading in Unit 34000 and 35000,
whereas the produced stabilized condensate is offloaded tandem to the condensate
tanker by using hose reel in Unit 36000.
The majority of the process facilities are located on the topsides, with some facilities
such as tank storages and loading pumps located within the substructure.

13.2 Pressure Relief System

The purpose of the pressure relief and liquid disposal systems (U63000) is to collect
and safely dispose of hydrocarbon-containing vapour and liquid streams that are
released during start-up, shutdown, venting, draining, upsets, maintenance and
emergency situations. The pressure relief system composes of:
• Dry Flare System - comprising of a HP system which protects primarily process
equipment and a LP system which provides relief for storage tanks.
• Wet Flare System - comprising of a HP system which protects primarily process
equipment and a LP system which provides relief for storage tanks.
• Acid Gas Vent - where CO2 extracted from the gas is vented to atmosphere.
• Marine Vent - final pressure protection for the condensate and cryogenic tanks. It is not
expected that significant GHG emissions will be emitted from the Marine Vent which has
a flow meter.
• Maintenance Vent - final pressure protection for the condensate and cryogenic tanks
during maintenance activities on the flare system. The maintenance vent is located in a
different area to the main flare, to allow for safe maintenance on the flare system in the
event of a gas release through the maintenance vent. The maintenance vent is also
used during maintenance of the tanks (e.g. warming up, purging, aerating and gassing-
up procedures). It is not expected that significant GHG emissions will be emitted from
the Maintenance Vent which has a flow meter.

13.3 Steam, Power Generation & Condensate Recovery

Prelude Steam and Power Generation and Distribution design is based on a steam
cogeneration system to supply services to the FLNG facility at the required quality,
availability and reliability during all operation modes. Since the plant is an offshore unit,
the power generation system is based on a stand-alone operation. The purpose of
Steam and Power Generation and Distribution System (Unit 40000) is to generate
electricity in the plant and supply heat in the form of steam to generate power.
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Prelude total design power requirement is 74.9 (64.9+10) MW including the thrusters.
Total design steam requirement is around 1300 tons/hr. Based on this total, 7 (6+1)
steam generator boilers are installed on the topsides, each with a Maximum
Continuous Rating (MCR) of 220 tons/hr capacity. The main electrical power
generation is produced by 3 (2+1) steam turbine generators of 40 MW
Extraction/Condensing Steam Turbines. Steam turbine generators are supplied with
HP Steam directly from Marine Steam Boilers to produce electricity for all the process
and non-process electrical consumers.
In addition to the main power generation, three Essential Marine Diesel Generators
(EDG), (3 x 7.68 MW), are on stand-by during normal operations. The function of these
EDGs include providing power to critical instrumentation load during process shut
down.
Emergency power is provided by two SOLAS designated emergency generator sets (A-
40210) having capacity 1250kw, located aft, supplemented by (A-40220) emergency
generator having capacity 750kw, located forward for secondary refuge power.
Autonomy of the Emergency power generator is 24hr in accordance with SOLAS
requirements in order to supply electricity to SOLAS critical equipment (e.g. control and
safety systems, Navigational aids, Communications used in emergency, Emergency
lighting; and Fire-fighting foam pumps).
In addition, uninterruptible power supply (UPS) supplies for a limited amount of time
systems such as the DCS, HVAC system, telecommunications, navigational aids or
other vital systems.
Electrical
Power

PCC
POWER
LP-steam PROCESS PCC CONDENSATE
GENERATION
HEATING RECOVERY
(U-40000)
(U-41000)

LP FUEL HP STEAM
GAS PRODUCTION HP-
SYSTEM (BOILERS) steam
(U-44000) (U-40000)

NCC DEMIN
NCC CONDENSATE WATER
RECOVERY PRODUCTION
PROCESS (U-41000) (U-43000)
COMPRESSOR
BFW DRIVES

NCC

Sea DESALINATION Fresh Water Make

-Up
Water
UNIT (U-43000)
BOILER FEED Intake
WATER Demineralised Water
TREATMENT
(U-43000)
CLOSED COOLING WATER
SYSTEM (U-45000)

SEA WATER COOLING Sea Water

SYSTEM (U-42000) Outfall

Figure 13-2: Prelude Utility Concept and Block Scheme

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Fuel Gas System

Fuel Gas System Unit U-44000 is designed to collect different sources of process
gases, to heat them via heater and mix them in order to supply fuel gas to identified
consumers at defined pressure, temperature, flow rate and quality (wet or dry). In order
to improve the reliability and availability of the fuel gas to consumers, several sources
of process gas are provided to the unit with available back-up sources. Dry fuel gas is
used as purge to dry flare and blanketing of LNG/LPG tanks. Whereas the mixed fuel
gas is used for the boilers, purge to wet flare and blanketing of condensate tanks.
Total fuel gas design demand for Prelude is about 97tons/hr corresponding to the total
required HP steam production for the operation of 6 boilers. In addition to fuel gas
requirements for steam boilers, 80kg/hr of continuous fuel gas is accounted for all flare
pilot burners consumption.
Diesel System
Diesel fuel is used for backup power generation in case of non-availability of fuel gas.
The design of the diesel oil system includes receipt through diesel bunker, store, treat
and distribute low Sulphur diesel oil to various consumers in the Hull and Topsides and
to occasionally refuel the supply boats.
Diesel fuel is transported by a supply boat and transferred through hose reel (or
alternatively through a secondary diesel oil loading station located at the aft deck
boarding) via the diesel filter and a bidirectional metering unit to the storage tanks.
Four diesel storage tanks, each with 750m3 storage volume have been provided for
diesel storage in the FLNG’s substructure. The Essential diesel generators, aft fire
water pump and aft emergency diesel generator have their own day storage tanks.
Similarly, the forward Emergency diesel generator and forward fire water pump have
their day storage tanks for storing the diesel oil.

13.4 Seawater Cooling & Essential Seawater Cooling System

The Sea Water Cooling Systems 2, 3 and 4 (U42000) and Essential Sea Water Cooling
System 1 (U42500) are to provide sea water for cooling of the following systems:
• Essential Diesel Generators Closed Cooling Water loops, by Essential Sea Water
Cooling System 1 (SW1)
• Closed cooling water 2 loop, by Sea water cooling system 2 (SW2)
• Closed Cooling Water 3 loop, by Sea Water Cooling System 3 (SW3)
• Steam Turbine Generators condensers, by Sea Water Cooling System 4 (SW4).
The purpose of the Essential Closed Cooling Water System 1 (CCW1) is to provide the
continuous cooling water to the Essential Diesel Generator packages. The purpose of
Closed Cooling Water System 2 (CCW2) is to provide cooling water for cooling
requirement of the topsides process users of the FLNG facility. The purpose of Closed
Cooling Water System 3 is to provide the cooling requirement of HVAC, IA
compressors and dryers, hydraulic power units, electrical users, STG auxiliaries,
thrusters, steam/condensate system users, and HP Nitrogen Compressor.

13.5 Water Distillation

The purpose of Seawater Distillation, Service Water, Potable Water, Demineralisation
Water Storage and Boiler Feed Water Facilities (Unit U43000) is:
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• To supply water in the form of:

o Potable Water to its respective users
o Service Water for utility stations and hose connection
o Make-up water for steam and condensate systems losses and for mixed beds
o Regeneration.
• To treat Potentially Contaminated Condensate with Heavy Hydrocarbons (PCH).
• To supply de-mineralized water (DMW) to its respective users.
• To supply Boiler Feed Water (BFW) to boilers and de-superheating water to its
respective users.

Seawater Distillation
The seawater distillation system removes salts from seawater to produce desalinated
water. The produced distillate is then distributed to the service and potable water
facilities and as make-up water for replacement of condensate and steam losses.
As the seawater is chlorinated to limit marine growth in the system it must be de-
chlorinated prior to entering the distillation units to prevent contamination. The
seawater is vaporised and the resulting distillate is cooled and routed to downstream
users. The brine produced from the distillation process is routed overboard.
To clean the unit and remove the scale which has not been eliminated by the
continuous feed water chemical treatment, an acid cleaning of the unit is performed
using a weak acid (sulfamic acid or equivalent). The weak acidic solution remaining
after cleaning is sent to the neutralisation tank to be neutralised before being
discharged to the sea.
Desalinated water from the distillation unit is re-mineralised in a hardener bed to
produce potable water.
Demineralised and Boiler Feed Water Facilities
The demineralised and BFW facilities are provided to generate water with the required
specification to allow for HP steam generation. Impure water will cause corrosion and
scaling in the steam system and cause unnecessary downstream intervention and
maintenance.
Power generation is based on a steam cogeneration system. Electrical power
generation is by STGs. Heat is supplied by marine boilers fed with BFW to produce HP
steam. The steam is then routed to downstream process and non-process users. The
resulting steam condensation are treated to produce demineralised water which is then
used as BFW.
To produce de-mineralised water (DMW) of the desired specification, mixed bed
exchange polishers (two in operation, one stand-by/regeneration) are provided. The
DMW further passes through three spray type de-aerators to produce boiler feed water.
The BFW is then pumped to the boilers. BFW is also used as medium for de-
superheating and turbine washing. After BFW has been used for boiler operations,
boiler blowdown is discharged to sea with flashed steam.
There is a neutralisation tank associated with the mixed bed polisher (MBP)
regeneration process, which is a water treatment package prior to being fed into the

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boiler feed water tank. The MBP regeneration process uses acid (HCl) and base
(NaOH) to remove anions and cations from the beads in MBP unit. This regeneration
waste liquid is then sent to the neutralisation tank for treatment (‘pH neutralisation’)
before being discharged to sea. The neutralisation tank recirculation line and
discharge lines also have an online analyser and alarm systems set on them which
measures pH.

13.6 Electro-chlorination Unit

The Unit 46000 Seawater Fouling Inhibition is also known as electro chlorination unit.
The function of the Electro chlorination unit is to generate, store and inject sodium
hypochlorite into following systems containing seawater:
• Cooling sea water circuits to protect equipment against bio-fouling (SW2 intake risers,
SW1/SW3/SW4 sea chest intakes)
• Seawater Distillation Packages A-43010/43020/43030 seawater intake
• Firewater pumps P-60001A/B and firewater jockey pumps P-60002/P-63003 circuits
• Diesel firewater pumps P-60000 A/B sea chests.
By using the process of electrolysis of seawater, the sodium hypochlorite required to
treat the seawater can be produced from the seawater itself. This is achieved by
passing a quantity of seawater through an electrolyser cell and applying a DC current
across the cell. The resulting electrolytic reaction produces sodium hypochlorite and
hydrogen.
Continually dosing into seawater systems at low concentrations effectively prevents
organic and bacteriological (mussels, barnacles and sea anemones) growth which
could cause fouling/plugging or corrosion in the system. However over a period of time
microorganisms (bacteria, slime and algae) can become chlorine resistant therefore an
intermittent (once or twice a day) shock dose at a higher concentrations is required.
Local generation onboard removes the need to import and store large quantities of
sodium hypochlorite solution.
On rare occasions such as during maintenance or shutdown periods, not all seawater
systems on the FLNG will be in operation. When the seawater systems are not
operational, the ECU will continue to generate hypochlorite that will be disposed to sea
for example via the sea chests. This is also the case for the firewater sea chests where
any excess hypochlorite will be discharged to sea if the firewater systems are not in
operation.

13.7 Mono-ethylene Glycol (MEG) System

The purpose of the MEG unit U52000 is to concentrate and reclaim rich MEG coming
from Produced Water Treatment Unit (U64000) prior to reinjection into subsea facilities
or topsides for hydrate prevention. Lean MEG is injected intermittently to the subsea
facilities during following cases. The first four of these cases make up the primary use
of MEG during SURU and normal operations:
• Before a planned shutdown
• When plant is down after any planned or unplanned shutdown (at each well)
• During any start-up

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• During adverse weather, to pre-treat flow lines in the event of an unplanned shutdown
• During gas sweeping operations (before start-up)
• For well annulus management, during normal operation.
Lean MEG is also injected topsides in the inlet facilities (U10000) for hydrate
prevention in the flare lines.
For rich MEG storage, there are two tanks in the substructure with a capacity of 6000
m3 each and one forward rich MEG tank with a capacity of 2000 m3. The MEG
regeneration system has a design capacity to regenerate about 30 m3/day at 20 wt %
rich MEG.

13.8 Effluent Treatment and Disposal System

Prelude Effluent and Waste Treating and disposal U64000 is divided into three main
sections, each with different objectives:
• Degassing section
• Hydrocarbon extraction section, Macro Porous Polymer Extraction (MPPE)
• Disposal section.
The inlet facilities U10000 receive produced water (PW) from production wells. This
produced water along with oily contaminated streams from other units is routed to
U64000, on either continuous or intermittent basis as indicated below:
Continuous produced water flow is from inlet facilities U10000:
• Produced water from LP separators
• Condensate stabilizer draw vessel.
The following intermittent streams are routed to the water treatment unit:
• Water from sand handling package (A-10010)
• Wash water bleed from AGRU solvent regeneration reflux pumps
• Dehydration unit regeneration water (U13000)
• Contaminated steam condensate from PCL and PCH collection headers (U41000)
• Clean Slop tank
• Produced water from MEG Regeneration and Reclaiming package A-52010.
The degassing section refers to the section between produced water inlet and
produced water buffer tank. This first section collects produced water and other
effluents from several sources and achieves their degassing, primary hydrocarbon
removal and cooling. This section includes Produced Water Flash Gas Package (A-
64030), Produced Water Cooler (E-64001A/B/C) and a Produced Water Buffer Tank
(T-64001). The inlet produced water streams are first routed to a water flash gas vessel
where the pressure is reduced to the LP wet flare operating pressure. This degasses
the dissolved hydrocarbon in the produced water inlet streams. The degassed stream
is then cooled to 34ºC by the produced water cooler; this is the optimum operating
temperature for the downstream Macro Porous Polymer Extraction (MPPE). The water
is stored in a buffer tank, before being processed in the MPPE unit.

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Pumps from the produced water buffer tank transfer water with traces of hydrocarbon
to the hydrocarbon extraction section i.e. the MPPE package (A-64010). One MPPE
package (A-64010) is designed to remove dispersed and dissolved hydrocarbons from
the water via extraction. After treatment, the treated water is checked to ensure
specifications for overboard discharges are satisfied. To meet the oil discharge limit,
the MPPE system removes dissolved and dispersed hydrocarbons from the feed water
by means of extraction in a MPPE bed.
The unit consists of four columns (two in service: one in extraction mode and one in
regeneration mode, and two in stand-by) containing a packed bed of macro porous
polymer extraction material which is oleophilic and hydrophobic. Two spared columns
located within the package allow for the change-out of the extraction columns for
onshore regeneration. Each column will have its installed spared column with a set of
manual valves to allow operator manual change over. It runs continuously to treat
water from produced water buffer tank. It can also receive off-spec water from Clean
Slop tanks via the produced water tank. Clean water from the Slop Tanks is normally
discharged overboard to sea under oil in water content monitoring. However, in case
concentrations exceed specified discharge limits, the overboard discharge is ceased,
and oily water is routed to the Produced water buffer tank after recycle within slop
tanks. During the column regeneration phase, very low pressure steam is used to
evaporate the components from the macro porous polymer extraction material,
resulting in a vapour flow of mixed hydrocarbons and steam. The vapour is routed
through a condenser where condensation of both steam and hydrocarbons takes place
by cooling with closed cooling water (CCW3). The extracted hydrocarbon (BTEX rich)
as a by-product is collected in the overhead vessel, which is pumped back to the
hydrocarbon condensate streams at the upstream of rundown cooler in U10000.
The treated water is monitored for oil content and reprocessed if found off-spec. The
on-spec water is routed overboard for disposal to the sea.

13.9 Drains
The intent of the drain system is to provide a safe and environmentally acceptable
method of collecting and disposing of:
• Cleaning water
• Recyclable liquid hydrocarbons as oily water
• Separately collected “other” liquids handled on the FLNG.
The drain systems are segregated into different zones and separate systems to avoid
cross contamination, thus allowing for more efficient, safer spill and drain management
taking into account:
• Cryogenic modules and fluids
• Non-Hazardous areas and fluids
• Hazardous areas and fluids.

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Figure 13-3: Drainage Zone Areas

Open Drains
The open drain system is composed of several segregated sub-systems, each with a
different function and hierarchy. The open drains systems (U65000) are used only after
unit depressurization for maintenance works and are also used to collect rain water,
firewater deluge, washing water and lube oil leaks from drip trays of equipment. The
intent of the open drain system is not to collect the liquid products during emptying of
the connected hydrocarbon processing system. There is no hard piping connected from
process equipment to the open drain system. The open drain material is either treated
in effluent water treatment unit or reprocessed in U10000 or stored in dirty Slop/ bilge
tank. The open drain systems include the;
• Open Hazardous Drain System (OHD)
• Open Non-Hazardous Drain System (OD)
• Open Chemical Drain System (OCD)
• Open Steam Condensate Drain System (OSD)
• Open Bilge Drain (OBD).
The Open Hazardous Drain system (OHD) and Open Non-Hazardous Drain System
(OD), drain headers are sloped towards the respective open drain vessels. The fluids
from the drip trays and tundishes are gravity-fed into the open drain vessels where oily
water is separated and transferred to the Slop /bilge tanks respectively.
In the hazardous areas drains system, any oil/accidentally oil contaminated water is
sent to the Dirty Slop tanks via the Open Hazardous Drain pumps. Oil Discharge
Monitoring Equipment (ODME) is provided to monitor oil/condensate content in water
before being discharged overboard from Clean Slop tanks. In case of off-spec water
stream, the recirculation valve is open to return the off-spec stream back to Dirty Slop
tanks, or to MPPE package for treatment. Open non-hazardous area drains are
completely segregated from any other open or closed drain system to avoid
hydrocarbon vapour transmission from one drain to a nonhazardous one.
The Open Chemical Drain (OCD) system collects chemical spills from open drip trays
and tundishes from topsides process modules, main deck and turret area. Drip pans in
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U50000 (Chemical Injection), U11000 (Acid Gas Removal Unit) and U52000 (MEG
Regeneration Unit) are connected to both the open bilge drain header and open
chemical drain header. The chemical spills drain header from hazardous and
nonhazardous areas are segregated. The chemical spills drain header from the
hazardous areas are sloped towards the Chemical Spills Collection tank. Collected
chemicals are pumped via Chemical Spills Collection pump to portable containers (tote
tanks) before onshore treatment.
The open steam condensate drain system (OSD) is provided to collect the Steam
Condensate from the steam traps of the Steam Turbine, from the drip holes (located on
Relief Valve discharge lines), from the silencers lines and from the level instruments.
The Open Bilge Drains System (OBD) covers the open drains facilities on the Main
Deck (e.g. Aft/Forward Coamings, exposed deck scupper system, etc.), void space,
insulation space (IS), cofferdam (C/D), bunker stations and machinery space. The
liquid collected is drained by gravity and discharged closed to pneumatic pumps and
then pumped to the dirty Slop Tanks (for hazardous areas) or dirty bilge tanks (for
nonhazardous areas). However, the cofferdam bilges is routed to the dirty slop tanks.
Closed Drains
Two closed systems exist for the HC drainage, which divert liquids to the flare system
(U63000). These closed drains are used for emptying vessel inventories after
depressurisation and prior to maintenance. The closed systems are:
• Closed hydrocarbon Drain (CD)
• Cryogenic Drain (CRD).
All deck areas where there is a risk of cryogenic/LPG spill hazard are freely drained
directly overboard. This is to avoid the risk of explosive clouds when cryogenics/LPG
spills vaporise. The primary steel structure is protected from cryogenic spills by suitable
coatings. Equipment and piping in cryogenic service have minimum flanges and
maximum welded connections. However, cryogenic protection on the main deck is
provided on location where there is high volume of cryogenic liquid is handled e.g.
offloading area, 3S1 based on the cryogenic spill risk assessment.

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14.0 Appendix B: EPBC Act Protected Matters Reports

This appendix consists of two reports issued by the Australian Government Department
of the Environment and Energy (renamed to Department of Agriculture, Water and the
Environment at the time of submission of this EP):
• EPBC Act Protected Matters Report, Report created: 27/02/19 08:09:05 (13 pages)
• EPBC Act Protected Matters Report, Report created: 03/09/19 15:03:57 (33 pages)

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EPBC Act Protected Matters Report
This report provides general guidance on matters of national environmental significance and other matters
protected by the EPBC Act in the area you have selected.

Information on the coverage of this report and qualifications on data supporting this report are contained in the
caveat at the end of the report.

Information is available about Environment Assessments and the EPBC Act including significance guidelines,
forms and application process details.

Report created: 27/02/19 08:09:05

Summary
Details
Matters of NES
Other Matters Protected by the EPBC Act
Extra Information
Caveat
Acknowledgements

This map may contain data which are

©Commonwealth of Australia
(Geoscience Australia), ©PSMA 2010

Coordinates
Buffer: 5.0Km
Summary
Matters of National Environmental Significance
This part of the report summarises the matters of national environmental significance that may occur in, or may
relate to, the area you nominated. Further information is available in the detail part of the report, which can be
accessed by scrolling or following the links below. If you are proposing to undertake an activity that may have a
significant impact on one or more matters of national environmental significance then you should consider the
Administrative Guidelines on Significance.

World Heritage Properties: None

National Heritage Places: None
Wetlands of International Importance: None
Great Barrier Reef Marine Park: None
Commonwealth Marine Area: 1
Listed Threatened Ecological Communities: None
Listed Threatened Species: 19
Listed Migratory Species: 31

Other Matters Protected by the EPBC Act

This part of the report summarises other matters protected under the Act that may relate to the area you nominated.
Approval may be required for a proposed activity that significantly affects the environment on Commonwealth land,
when the action is outside the Commonwealth land, or the environment anywhere when the action is taken on
Commonwealth land. Approval may also be required for the Commonwealth or Commonwealth agencies proposing to
take an action that is likely to have a significant impact on the environment anywhere.

The EPBC Act protects the environment on Commonwealth land, the environment from the actions taken on
Commonwealth land, and the environment from actions taken by Commonwealth agencies. As heritage values of a
place are part of the 'environment', these aspects of the EPBC Act protect the Commonwealth Heritage values of a
Commonwealth Heritage place. Information on the new heritage laws can be found at
http://www.environment.gov.au/heritage

A permit may be required for activities in or on a Commonwealth area that may affect a member of a listed threatened
species or ecological community, a member of a listed migratory species, whales and other cetaceans, or a member of
a listed marine species.

Commonwealth Land: None

Commonwealth Heritage Places: None
Listed Marine Species: 59
Whales and Other Cetaceans: 22
Critical Habitats: None
Commonwealth Reserves Terrestrial: None
Australian Marine Parks: None

Extra Information
This part of the report provides information that may also be relevant to the area you have nominated.

State and Territory Reserves: None

Regional Forest Agreements: None
Invasive Species: None
Nationally Important Wetlands: None
Key Ecological Features (Marine) None
Details
Matters of National Environmental Significance
Commonwealth Marine Area [ Resource Information ]
Approval is required for a proposed activity that is located within the Commonwealth Marine Area which has, will have, or is
likely to have a significant impact on the environment. Approval may be required for a proposed action taken outside the
Commonwealth Marine Area but which has, may have or is likely to have a significant impact on the environment in the
Commonwealth Marine Area. Generally the Commonwealth Marine Area stretches from three nautical miles to two hundred
nautical miles from the coast.

Name
EEZ and Territorial Sea

Marine Regions [ Resource Information ]

If you are planning to undertake action in an area in or close to the Commonwealth Marine Area, and a marine
bioregional plan has been prepared for the Commonwealth Marine Area in that area, the marine bioregional
plan may inform your decision as to whether to refer your proposed action under the EPBC Act.

Name
North-west

Listed Threatened Species [ Resource Information ]

Name Status Type of Presence
Birds
Anous tenuirostris melanops
Australian Lesser Noddy [26000] Vulnerable Species or species habitat
may occur within area

Calidris canutus
Red Knot, Knot [855] Endangered Species or species habitat
may occur within area

Calidris ferruginea
Curlew Sandpiper [856] Critically Endangered Species or species habitat
may occur within area

Numenius madagascariensis
Eastern Curlew, Far Eastern Curlew [847] Critically Endangered Species or species habitat
may occur within area

Papasula abbotti
Abbott's Booby [59297] Endangered Species or species habitat
may occur within area

Mammals
Balaenoptera borealis
Sei Whale [34] Vulnerable Species or species habitat
likely to occur within area

Balaenoptera musculus
Blue Whale [36] Endangered Species or species habitat
likely to occur within area

Balaenoptera physalus
Fin Whale [37] Vulnerable Species or species habitat
likely to occur within area

Megaptera novaeangliae
Humpback Whale [38] Vulnerable Species or species
Name Status Type of Presence
habitat likely to occur within
area
Reptiles
Caretta caretta
Loggerhead Turtle [1763] Endangered Species or species habitat
likely to occur within area

Chelonia mydas
Green Turtle [1765] Vulnerable Species or species habitat
likely to occur within area

Dermochelys coriacea
Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Species or species habitat
likely to occur within area

Eretmochelys imbricata
Hawksbill Turtle [1766] Vulnerable Species or species habitat
likely to occur within area

Lepidochelys olivacea
Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Species or species habitat
likely to occur within area

Natator depressus
Flatback Turtle [59257] Vulnerable Species or species habitat
likely to occur within area

Sharks
Carcharodon carcharias
White Shark, Great White Shark [64470] Vulnerable Species or species habitat
may occur within area

Glyphis garricki
Northern River Shark, New Guinea River Shark Endangered Species or species habitat
[82454] may occur within area

Pristis zijsron
Green Sawfish, Dindagubba, Narrowsnout Sawfish Vulnerable Species or species habitat
[68442] known to occur within area

Rhincodon typus
Whale Shark [66680] Vulnerable Species or species habitat
may occur within area

Listed Migratory Species [ Resource Information ]

* Species is listed under a different scientific name on the EPBC Act - Threatened Species list.
Name Threatened Type of Presence
Migratory Marine Birds
Anous stolidus
Common Noddy [825] Species or species habitat
may occur within area

Calonectris leucomelas
Streaked Shearwater [1077] Species or species habitat
known to occur within area

Fregata ariel
Lesser Frigatebird, Least Frigatebird [1012] Species or species habitat
likely to occur within area

Fregata minor
Great Frigatebird, Greater Frigatebird [1013] Foraging, feeding or related
behaviour likely to occur
within area
Migratory Marine Species
Anoxypristis cuspidata
Narrow Sawfish, Knifetooth Sawfish [68448] Species or species habitat
may occur within area

Balaenoptera borealis
Sei Whale [34] Vulnerable Species or species
Name Threatened Type of Presence
habitat likely to occur within
area
Balaenoptera edeni
Bryde's Whale [35] Species or species habitat
likely to occur within area

Balaenoptera musculus
Blue Whale [36] Endangered Species or species habitat
likely to occur within area

Balaenoptera physalus
Fin Whale [37] Vulnerable Species or species habitat
likely to occur within area

Carcharodon carcharias
White Shark, Great White Shark [64470] Vulnerable Species or species habitat
may occur within area

Caretta caretta
Loggerhead Turtle [1763] Endangered Species or species habitat
likely to occur within area

Chelonia mydas
Green Turtle [1765] Vulnerable Species or species habitat
likely to occur within area

Dermochelys coriacea
Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Species or species habitat
likely to occur within area

Eretmochelys imbricata
Hawksbill Turtle [1766] Vulnerable Species or species habitat
likely to occur within area

Isurus oxyrinchus
Shortfin Mako, Mako Shark [79073] Species or species habitat
likely to occur within area

Isurus paucus
Longfin Mako [82947] Species or species habitat
likely to occur within area

Lepidochelys olivacea
Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Species or species habitat
likely to occur within area

Manta birostris
Giant Manta Ray, Chevron Manta Ray, Pacific Manta Species or species habitat
Ray, Pelagic Manta Ray, Oceanic Manta Ray [84995] may occur within area

Megaptera novaeangliae
Humpback Whale [38] Vulnerable Species or species habitat
likely to occur within area

Natator depressus
Flatback Turtle [59257] Vulnerable Species or species habitat
likely to occur within area

Orcinus orca
Killer Whale, Orca [46] Species or species habitat
may occur within area

Physeter macrocephalus
Sperm Whale [59] Species or species habitat
may occur within area

Pristis zijsron
Green Sawfish, Dindagubba, Narrowsnout Sawfish Vulnerable Species or species habitat
[68442] known to occur within area

Rhincodon typus
Whale Shark [66680] Vulnerable Species or species habitat
may occur within
Name Threatened Type of Presence
area
Tursiops aduncus (Arafura/Timor Sea populations)
Spotted Bottlenose Dolphin (Arafura/Timor Sea Species or species habitat
populations) [78900] may occur within area

Migratory Wetlands Species

Actitis hypoleucos
Common Sandpiper [59309] Species or species habitat
may occur within area

Calidris acuminata
Sharp-tailed Sandpiper [874] Species or species habitat
may occur within area

Calidris canutus
Red Knot, Knot [855] Endangered Species or species habitat
may occur within area

Calidris ferruginea
Curlew Sandpiper [856] Critically Endangered Species or species habitat
may occur within area

Calidris melanotos
Pectoral Sandpiper [858] Species or species habitat
may occur within area

Numenius madagascariensis
Eastern Curlew, Far Eastern Curlew [847] Critically Endangered Species or species habitat
may occur within area

Other Matters Protected by the EPBC Act

Listed Marine Species [ Resource Information ]
* Species is listed under a different scientific name on the EPBC Act - Threatened Species list.
Name Threatened Type of Presence
Birds
Actitis hypoleucos
Common Sandpiper [59309] Species or species habitat
may occur within area

Anous stolidus
Common Noddy [825] Species or species habitat
may occur within area

Anous tenuirostris melanops

Australian Lesser Noddy [26000] Vulnerable Species or species habitat
may occur within area

Calidris acuminata
Sharp-tailed Sandpiper [874] Species or species habitat
may occur within area

Calidris canutus
Red Knot, Knot [855] Endangered Species or species habitat
may occur within area

Calidris ferruginea
Curlew Sandpiper [856] Critically Endangered Species or species habitat
may occur within area

Calidris melanotos
Pectoral Sandpiper [858] Species or species habitat
may occur within area

Calonectris leucomelas
Streaked Shearwater [1077] Species or species habitat
known to occur
Name Threatened Type of Presence
within area
Fregata ariel
Lesser Frigatebird, Least Frigatebird [1012] Species or species habitat
likely to occur within area

Fregata minor
Great Frigatebird, Greater Frigatebird [1013] Foraging, feeding or related
behaviour likely to occur
within area
Numenius madagascariensis
Eastern Curlew, Far Eastern Curlew [847] Critically Endangered Species or species habitat
may occur within area

Papasula abbotti
Abbott's Booby [59297] Endangered Species or species habitat
may occur within area

Fish
Bhanotia fasciolata
Corrugated Pipefish, Barbed Pipefish [66188] Species or species habitat
may occur within area

Campichthys tricarinatus
Three-keel Pipefish [66192] Species or species habitat
may occur within area

Choeroichthys brachysoma
Pacific Short-bodied Pipefish, Short-bodied Pipefish Species or species habitat
[66194] may occur within area

Choeroichthys suillus
Pig-snouted Pipefish [66198] Species or species habitat
may occur within area

Corythoichthys amplexus
Fijian Banded Pipefish, Brown-banded Pipefish Species or species habitat
[66199] may occur within area

Corythoichthys flavofasciatus
Reticulate Pipefish, Yellow-banded Pipefish, Network Species or species habitat
Pipefish [66200] may occur within area

Corythoichthys intestinalis
Australian Messmate Pipefish, Banded Pipefish Species or species habitat
[66202] may occur within area

Corythoichthys schultzi
Schultz's Pipefish [66205] Species or species habitat
may occur within area

Cosmocampus banneri
Roughridge Pipefish [66206] Species or species habitat
may occur within area

Doryrhamphus dactyliophorus
Banded Pipefish, Ringed Pipefish [66210] Species or species habitat
may occur within area

Doryrhamphus excisus
Bluestripe Pipefish, Indian Blue-stripe Pipefish, Pacific Species or species habitat
Blue-stripe Pipefish [66211] may occur within area

Doryrhamphus janssi
Cleaner Pipefish, Janss' Pipefish [66212] Species or species habitat
may occur within area

Filicampus tigris
Tiger Pipefish [66217] Species or species habitat
may occur within area

Halicampus brocki
Brock's Pipefish [66219] Species or species habitat
may occur within
Name Threatened Type of Presence
area
Halicampus dunckeri
Red-hair Pipefish, Duncker's Pipefish [66220] Species or species habitat
may occur within area

Halicampus grayi
Mud Pipefish, Gray's Pipefish [66221] Species or species habitat
may occur within area

Halicampus spinirostris
Spiny-snout Pipefish [66225] Species or species habitat
may occur within area

Haliichthys taeniophorus
Ribboned Pipehorse, Ribboned Seadragon [66226] Species or species habitat
may occur within area

Hippichthys penicillus
Beady Pipefish, Steep-nosed Pipefish [66231] Species or species habitat
may occur within area

Hippocampus histrix
Spiny Seahorse, Thorny Seahorse [66236] Species or species habitat
may occur within area

Hippocampus kuda
Spotted Seahorse, Yellow Seahorse [66237] Species or species habitat
may occur within area

Hippocampus planifrons
Flat-face Seahorse [66238] Species or species habitat
may occur within area

Hippocampus spinosissimus
Hedgehog Seahorse [66239] Species or species habitat
may occur within area

Micrognathus micronotopterus
Tidepool Pipefish [66255] Species or species habitat
may occur within area

Solegnathus hardwickii
Pallid Pipehorse, Hardwick's Pipehorse [66272] Species or species habitat
may occur within area

Solegnathus lettiensis
Gunther's Pipehorse, Indonesian Pipefish [66273] Species or species habitat
may occur within area

Solenostomus cyanopterus
Robust Ghostpipefish, Blue-finned Ghost Pipefish, Species or species habitat
[66183] may occur within area

Syngnathoides biaculeatus
Double-end Pipehorse, Double-ended Pipehorse, Species or species habitat
Alligator Pipefish [66279] may occur within area

Trachyrhamphus bicoarctatus
Bentstick Pipefish, Bend Stick Pipefish, Short-tailed Species or species habitat
Pipefish [66280] may occur within area

Trachyrhamphus longirostris
Straightstick Pipefish, Long-nosed Pipefish, Straight Species or species habitat
Stick Pipefish [66281] may occur within area

Reptiles
Acalyptophis peronii
Horned Seasnake [1114] Species or species habitat
may occur within area

Aipysurus duboisii
Dubois' Seasnake [1116] Species or species habitat
may occur within
Name Threatened Type of Presence
area
Aipysurus laevis
Olive Seasnake [1120] Species or species habitat
may occur within area

Astrotia stokesii
Stokes' Seasnake [1122] Species or species habitat
may occur within area

Caretta caretta
Loggerhead Turtle [1763] Endangered Species or species habitat
likely to occur within area

Chelonia mydas
Green Turtle [1765] Vulnerable Species or species habitat
likely to occur within area

Dermochelys coriacea
Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Species or species habitat
likely to occur within area

Disteira kingii
Spectacled Seasnake [1123] Species or species habitat
may occur within area

Disteira major
Olive-headed Seasnake [1124] Species or species habitat
may occur within area

Eretmochelys imbricata
Hawksbill Turtle [1766] Vulnerable Species or species habitat
likely to occur within area

Hydrophis coggeri
Slender-necked Seasnake [25925] Species or species habitat
may occur within area

Hydrophis elegans
Elegant Seasnake [1104] Species or species habitat
may occur within area

Hydrophis ornatus
Spotted Seasnake, Ornate Reef Seasnake [1111] Species or species habitat
may occur within area

Lapemis hardwickii
Spine-bellied Seasnake [1113] Species or species habitat
may occur within area

Lepidochelys olivacea
Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Species or species habitat
likely to occur within area

Natator depressus
Flatback Turtle [59257] Vulnerable Species or species habitat
likely to occur within area

Pelamis platurus
Yellow-bellied Seasnake [1091] Species or species habitat
may occur within area

Whales and other Cetaceans [ Resource Information ]

Name Status Type of Presence
Mammals
Balaenoptera borealis
Sei Whale [34] Vulnerable Species or species habitat
likely to occur within area

Balaenoptera edeni
Bryde's Whale [35] Species or species habitat
likely to occur within area
Name Status Type of Presence
Balaenoptera musculus
Blue Whale [36] Endangered Species or species habitat
likely to occur within area

Balaenoptera physalus
Fin Whale [37] Vulnerable Species or species habitat
likely to occur within area

Delphinus delphis
Common Dophin, Short-beaked Common Dolphin [60] Species or species habitat
may occur within area

Feresa attenuata
Pygmy Killer Whale [61] Species or species habitat
may occur within area

Globicephala macrorhynchus
Short-finned Pilot Whale [62] Species or species habitat
may occur within area

Grampus griseus
Risso's Dolphin, Grampus [64] Species or species habitat
may occur within area

Kogia breviceps
Pygmy Sperm Whale [57] Species or species habitat
may occur within area

Kogia simus
Dwarf Sperm Whale [58] Species or species habitat
may occur within area

Megaptera novaeangliae
Humpback Whale [38] Vulnerable Species or species habitat
likely to occur within area

Orcinus orca
Killer Whale, Orca [46] Species or species habitat
may occur within area

Peponocephala electra
Melon-headed Whale [47] Species or species habitat
may occur within area

Physeter macrocephalus
Sperm Whale [59] Species or species habitat
may occur within area

Pseudorca crassidens
False Killer Whale [48] Species or species habitat
likely to occur within area

Stenella attenuata
Spotted Dolphin, Pantropical Spotted Dolphin [51] Species or species habitat
may occur within area

Stenella coeruleoalba
Striped Dolphin, Euphrosyne Dolphin [52] Species or species habitat
may occur within area

Stenella longirostris
Long-snouted Spinner Dolphin [29] Species or species habitat
may occur within area

Steno bredanensis
Rough-toothed Dolphin [30] Species or species habitat
may occur within area

Tursiops aduncus (Arafura/Timor Sea populations)

Spotted Bottlenose Dolphin (Arafura/Timor Sea Species or species habitat
populations) [78900] may occur within area
Name Status Type of Presence
Tursiops truncatus s. str.
Bottlenose Dolphin [68417] Species or species habitat
may occur within area

Ziphius cavirostris
Cuvier's Beaked Whale, Goose-beaked Whale [56] Species or species habitat
may occur within area

Extra Information
Caveat
The information presented in this report has been provided by a range of data sources as acknowledged at the end of the report.

This report is designed to assist in identifying the locations of places which may be relevant in determining obligations under the Environment
Protection and Biodiversity Conservation Act 1999. It holds mapped locations of World and National Heritage properties, Wetlands of International
and National Importance, Commonwealth and State/Territory reserves, listed threatened, migratory and marine species and listed threatened
ecological communities. Mapping of Commonwealth land is not complete at this stage. Maps have been collated from a range of sources at various
resolutions.

Not all species listed under the EPBC Act have been mapped (see below) and therefore a report is a general guide only. Where available data
supports mapping, the type of presence that can be determined from the data is indicated in general terms. People using this information in making
a referral may need to consider the qualifications below and may need to seek and consider other information sources.

For threatened ecological communities where the distribution is well known, maps are derived from recovery plans, State vegetation maps, remote
sensing imagery and other sources. Where threatened ecological community distributions are less well known, existing vegetation maps and point
location data are used to produce indicative distribution maps.

Threatened, migratory and marine species distributions have been derived through a variety of methods. Where distributions are well known and if
time permits, maps are derived using either thematic spatial data (i.e. vegetation, soils, geology, elevation, aspect, terrain, etc) together with point
locations and described habitat; or environmental modelling (MAXENT or BIOCLIM habitat modelling) using point locations and environmental data
layers.

Where very little information is available for species or large number of maps are required in a short time-frame, maps are derived either from 0.04
or 0.02 decimal degree cells; by an automated process using polygon capture techniques (static two kilometre grid cells, alpha-hull and convex hull);
or captured manually or by using topographic features (national park boundaries, islands, etc). In the early stages of the distribution mapping
process (1999-early 2000s) distributions were defined by degree blocks, 100K or 250K map sheets to rapidly create distribution maps. More reliable
distribution mapping methods are used to update these distributions as time permits.

Only selected species covered by the following provisions of the EPBC Act have been mapped:
- migratory and
- marine
The following species and ecological communities have not been mapped and do not appear in reports produced from this database:

- threatened species listed as extinct or considered as vagrants

- some species and ecological communities that have only recently been listed
- some terrestrial species that overfly the Commonwealth marine area
- migratory species that are very widespread, vagrant, or only occur in small numbers
The following groups have been mapped, but may not cover the complete distribution of the species:
- non-threatened seabirds which have only been mapped for recorded breeding sites
- seals which have only been mapped for breeding sites near the Australian continent
Such breeding sites may be important for the protection of the Commonwealth Marine environment.

Coordinates
-13.78637 123.31754
Acknowledgements
This database has been compiled from a range of data sources. The department acknowledges the following
custodians who have contributed valuable data and advice:
-Office of Environment and Heritage, New South Wales
-Department of Environment and Primary Industries, Victoria
-Department of Primary Industries, Parks, Water and Environment, Tasmania
-Department of Environment, Water and Natural Resources, South Australia
-Department of Land and Resource Management, Northern Territory
-Department of Environmental and Heritage Protection, Queensland
-Department of Parks and Wildlife, Western Australia
-Environment and Planning Directorate, ACT
-Birdlife Australia
-Australian Bird and Bat Banding Scheme
-Australian National Wildlife Collection
-Natural history museums of Australia
-Museum Victoria
-Australian Museum
-South Australian Museum
-Queensland Museum
-Online Zoological Collections of Australian Museums
-Queensland Herbarium
-National Herbarium of NSW
-Royal Botanic Gardens and National Herbarium of Victoria
-Tasmanian Herbarium
-State Herbarium of South Australia
-Northern Territory Herbarium
-Western Australian Herbarium
-Australian National Herbarium, Canberra
-University of New England
-Ocean Biogeographic Information System
-Australian Government, Department of Defence
Forestry Corporation, NSW
-Geoscience Australia
-CSIRO
-Australian Tropical Herbarium, Cairns
-eBird Australia
-Australian Government – Australian Antarctic Data Centre
-Museum and Art Gallery of the Northern Territory
-Australian Government National Environmental Science Program
-Australian Institute of Marine Science
-Reef Life Survey Australia
-American Museum of Natural History
-Queen Victoria Museum and Art Gallery, Inveresk, Tasmania
-Tasmanian Museum and Art Gallery, Hobart, Tasmania
-Other groups and individuals

The Department is extremely grateful to the many organisations and individuals who provided expert advice
and information on numerous draft distributions.

Please feel free to provide feedback via the Contact Us page.

© Commonwealth of Australia
Department of the Environment
GPO Box 787
Canberra ACT 2601 Australia
+61 2 6274 1111
EPBC Act Protected Matters Report
This report provides general guidance on matters of national environmental significance and other matters
protected by the EPBC Act in the area you have selected.

Information on the coverage of this report and qualifications on data supporting this report are contained in the
caveat at the end of the report.

Information is available about Environment Assessments and the EPBC Act including significance guidelines,
forms and application process details.

Report created: 03/09/19 15:03:57

Summary
Details
Matters of NES
Other Matters Protected by the EPBC Act
Extra Information
Caveat
Acknowledgements

This map may contain data which are

©Commonwealth of Australia
(Geoscience Australia), ©PSMA 2010

Coordinates
Buffer: 1.0Km
Summary
Matters of National Environmental Significance
This part of the report summarises the matters of national environmental significance that may occur in, or may
relate to, the area you nominated. Further information is available in the detail part of the report, which can be
accessed by scrolling or following the links below. If you are proposing to undertake an activity that may have a
significant impact on one or more matters of national environmental significance then you should consider the
Administrative Guidelines on Significance.

World Heritage Properties: 2

National Heritage Places: 6
Wetlands of International Importance: 5
Great Barrier Reef Marine Park: None
Commonwealth Marine Area: 2
Listed Threatened Ecological Communities: 1
Listed Threatened Species: 100
Listed Migratory Species: 99

Other Matters Protected by the EPBC Act

This part of the report summarises other matters protected under the Act that may relate to the area you nominated.
Approval may be required for a proposed activity that significantly affects the environment on Commonwealth land,
when the action is outside the Commonwealth land, or the environment anywhere when the action is taken on
Commonwealth land. Approval may also be required for the Commonwealth or Commonwealth agencies proposing to
take an action that is likely to have a significant impact on the environment anywhere.

The EPBC Act protects the environment on Commonwealth land, the environment from the actions taken on
Commonwealth land, and the environment from actions taken by Commonwealth agencies. As heritage values of a
place are part of the 'environment', these aspects of the EPBC Act protect the Commonwealth Heritage values of a
Commonwealth Heritage place. Information on the new heritage laws can be found at
http://www.environment.gov.au/heritage

A permit may be required for activities in or on a Commonwealth area that may affect a member of a listed threatened
species or ecological community, a member of a listed migratory species, whales and other cetaceans, or a member of
a listed marine species.

Commonwealth Land: 9
Commonwealth Heritage Places: 18
Listed Marine Species: 195
Whales and Other Cetaceans: 34
Critical Habitats: None
Commonwealth Reserves Terrestrial: 1
Australian Marine Parks: 31

Extra Information
This part of the report provides information that may also be relevant to the area you have nominated.

State and Territory Reserves: 63

Regional Forest Agreements: None
Invasive Species: 38
Nationally Important Wetlands: 15
Key Ecological Features (Marine) 20
Details
Matters of National Environmental Significance
World Heritage Properties [ Resource Information ]
Name State Status
Shark Bay, Western Australia WA Declared property
The Ningaloo Coast WA Declared property

National Heritage Properties [ Resource Information ]

Name State Status
Natural
Shark Bay, Western Australia WA Listed place
The Ningaloo Coast WA Listed place
The West Kimberley WA Listed place
Indigenous
Dampier Archipelago (including Burrup Peninsula) WA Listed place
Historic
Dirk Hartog Landing Site 1616 - Cape Inscription Area WA Listed place
HMAS Sydney II and HSK Kormoran Shipwreck Sites EXT Listed place

Wetlands of International Importance (Ramsar) [ Resource Information ]

Name Proximity
Ashmore reef national nature reserve Within Ramsar site
Eighty-mile beach Within Ramsar site
Hosnies spring Within Ramsar site
Roebuck bay Within Ramsar site
The dales Within Ramsar site

Commonwealth Marine Area [ Resource Information ]

Approval is required for a proposed activity that is located within the Commonwealth Marine Area which has, will have, or is
likely to have a significant impact on the environment. Approval may be required for a proposed action taken outside the
Commonwealth Marine Area but which has, may have or is likely to have a significant impact on the environment in the
Commonwealth Marine Area. Generally the Commonwealth Marine Area stretches from three nautical miles to two hundred
nautical miles from the coast.

Name
EEZ and Territorial Sea
Extended Continental Shelf

Marine Regions [ Resource Information ]

If you are planning to undertake action in an area in or close to the Commonwealth Marine Area, and a marine
bioregional plan has been prepared for the Commonwealth Marine Area in that area, the marine bioregional
plan may inform your decision as to whether to refer your proposed action under the EPBC Act.

Name
North
North-west
South-west

Listed Threatened Ecological Communities [ Resource Information ]

For threatened ecological communities where the distribution is well known, maps are derived from recovery
plans, State vegetation maps, remote sensing imagery and other sources. Where threatened ecological
community distributions are less well known, existing vegetation maps and point location data are used to
produce indicative distribution maps.
Name Status Type of Presence
Monsoon vine thickets on the coastal sand dunes of Endangered Community likely to occur
Dampier Peninsula within area

Listed Threatened Species [ Resource Information ]

Name Status Type of Presence
Birds
Accipiter hiogaster natalis
Christmas Island Goshawk [82408] Endangered Species or species habitat
known to occur
Name Status Type of Presence
within area
Anous tenuirostris melanops
Australian Lesser Noddy [26000] Vulnerable Breeding known to occur
within area
Calidris canutus
Red Knot, Knot [855] Endangered Species or species habitat
known to occur within area

Calidris ferruginea
Curlew Sandpiper [856] Critically Endangered Species or species habitat
known to occur within area

Calidris tenuirostris
Great Knot [862] Critically Endangered Roosting known to occur
within area
Chalcophaps indica natalis
Christmas Island Emerald Dove, Emerald Dove Endangered Species or species habitat
(Christmas Island) [67030] known to occur within area

Charadrius leschenaultii
Greater Sand Plover, Large Sand Plover [877] Vulnerable Roosting known to occur
within area
Charadrius mongolus
Lesser Sand Plover, Mongolian Plover [879] Endangered Roosting known to occur
within area
Diomedea amsterdamensis
Amsterdam Albatross [64405] Endangered Species or species habitat
likely to occur within area

Diomedea epomophora
Southern Royal Albatross [89221] Vulnerable Species or species habitat
may occur within area

Diomedea exulans
Wandering Albatross [89223] Vulnerable Species or species habitat
may occur within area

Erythrotriorchis radiatus
Red Goshawk [942] Vulnerable Species or species habitat
likely to occur within area

Erythrura gouldiae
Gouldian Finch [413] Endangered Species or species habitat
known to occur within area

Falcunculus frontatus whitei

Crested Shrike-tit (northern), Northern Shrike-tit Vulnerable Species or species habitat
[26013] likely to occur within area

Fregata andrewsi
Christmas Island Frigatebird, Andrew's Frigatebird Endangered Breeding known to occur
[1011] within area
Geophaps smithii blaauwi
Partridge Pigeon (western) [66501] Vulnerable Species or species habitat
likely to occur within area

Leipoa ocellata
Malleefowl [934] Vulnerable Species or species habitat
may occur within area

Limosa lapponica baueri

Bar-tailed Godwit (baueri), Western Alaskan Bar-tailed Vulnerable Species or species habitat
Godwit [86380] known to occur within area

Limosa lapponica menzbieri

Northern Siberian Bar-tailed Godwit, Bar-tailed Godwit Critically Endangered Species or species habitat
(menzbieri) [86432] known to occur within area

Macronectes giganteus
Southern Giant-Petrel, Southern Giant Petrel [1060] Endangered Species or species habitat
may occur within area
Name Status Type of Presence
Macronectes halli
Northern Giant Petrel [1061] Vulnerable Species or species habitat
may occur within area

Malurus leucopterus edouardi

White-winged Fairy-wren (Barrow Island), Barrow Vulnerable Species or species habitat
Island Black-and-white Fairy-wren [26194] likely to occur within area

Malurus leucopterus leucopterus

White-winged Fairy-wren (Dirk Hartog Island), Dirk Vulnerable Species or species habitat
Hartog Black-and-White Fairy-wren [26004] likely to occur within area

Ninox natalis
Christmas Island Hawk-Owl, Christmas Boobook Vulnerable Species or species habitat
[66671] known to occur within area

Numenius madagascariensis
Eastern Curlew, Far Eastern Curlew [847] Critically Endangered Species or species habitat
known to occur within area

Papasula abbotti
Abbott's Booby [59297] Endangered Species or species habitat
known to occur within area

Pezoporus occidentalis
Night Parrot [59350] Endangered Species or species habitat
may occur within area

Phaethon lepturus fulvus

Christmas Island White-tailed Tropicbird, Golden Endangered Breeding likely to occur
Bosunbird [26021] within area
Polytelis alexandrae
Princess Parrot, Alexandra's Parrot [758] Vulnerable Species or species habitat
known to occur within area

Pterodroma mollis
Soft-plumaged Petrel [1036] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Rostratula australis
Australian Painted-snipe, Australian Painted Snipe Endangered Species or species habitat
[77037] known to occur within area

Sternula nereis nereis

Australian Fairy Tern [82950] Vulnerable Breeding known to occur
within area
Thalassarche carteri
Indian Yellow-nosed Albatross [64464] Vulnerable Foraging, feeding or related
behaviour may occur within
area
Thalassarche cauta cauta
Shy Albatross, Tasmanian Shy Albatross [82345] Vulnerable Species or species habitat
may occur within area

Thalassarche cauta steadi

White-capped Albatross [82344] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Thalassarche impavida
Campbell Albatross, Campbell Black-browed Albatross Vulnerable Species or species habitat
[64459] may occur within area

Thalassarche melanophris
Black-browed Albatross [66472] Vulnerable Species or species habitat
may occur within area

Turdus poliocephalus erythropleurus

Christmas Island Thrush [67122] Endangered Species or species habitat
likely to occur within area

Tyto novaehollandiae kimberli

Masked Owl (northern) [26048] Vulnerable Species or species habitat
likely to occur
Name Status Type of Presence
within area
Fish
Milyeringa veritas
Blind Gudgeon [66676] Vulnerable Species or species habitat
known to occur within area

Ophisternon candidum
Blind Cave Eel [66678] Vulnerable Species or species habitat
known to occur within area

Mammals
Balaenoptera borealis
Sei Whale [34] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Balaenoptera musculus
Blue Whale [36] Endangered Migration route known to
occur within area
Balaenoptera physalus
Fin Whale [37] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Bettongia lesueur Barrow and Boodie Islands subspecies
Boodie, Burrowing Bettong (Barrow and Boodie Vulnerable Species or species habitat
Islands) [88021] known to occur within area

Bettongia lesueur lesueur

Burrowing Bettong (Shark Bay), Boodie [66659] Vulnerable Species or species habitat
likely to occur within area

Bettongia penicillata ogilbyi

Woylie [66844] Endangered Species or species habitat
known to occur within area

Conilurus penicillatus
Brush-tailed Rabbit-rat, Brush-tailed Tree-rat, Vulnerable Species or species habitat
Pakooma [132] known to occur within area

Crocidura trichura
Christmas Island Shrew [86568] Critically Endangered Species or species habitat
likely to occur within area

Dasyurus geoffroii
Chuditch, Western Quoll [330] Vulnerable Species or species habitat
may occur within area

Dasyurus hallucatus
Northern Quoll, Digul [Gogo-Yimidir], Wijingadda Endangered Species or species habitat
[Dambimangari], Wiminji [Martu] [331] known to occur within area

Eubalaena australis
Southern Right Whale [40] Endangered Species or species habitat
likely to occur within area

Isoodon auratus auratus

Golden Bandicoot (mainland) [66665] Vulnerable Species or species habitat
likely to occur within area

Isoodon auratus barrowensis

Golden Bandicoot (Barrow Island) [66666] Vulnerable Species or species habitat
known to occur within area

Lagorchestes conspicillatus conspicillatus

Spectacled Hare-wallaby (Barrow Island) [66661] Vulnerable Species or species habitat
known to occur within area

Lagorchestes hirsutus Central Australian subspecies

Mala, Rufous Hare-Wallaby (Central Australia) [88019] Endangered Translocated population
known to occur within area

Lagorchestes hirsutus dorreae

Rufous Hare-wallaby (Dorre Island) [66663] Vulnerable Species or species habitat
known to occur
Name Status Type of Presence
within area
Lagostrophus fasciatus fasciatus
Banded Hare-wallaby, Merrnine, Marnine, Munning Vulnerable Species or species habitat
[66664] known to occur within area

Macroderma gigas
Ghost Bat [174] Vulnerable Species or species habitat
known to occur within area

Macrotis lagotis
Greater Bilby [282] Vulnerable Species or species habitat
known to occur within area

Megaptera novaeangliae
Humpback Whale [38] Vulnerable Breeding known to occur
within area
Mesembriomys gouldii gouldii
Black-footed Tree-rat (Kimberley and mainland Endangered Species or species habitat
Northern Territory), Djintamoonga, Manbul [87618] may occur within area

Osphranter robustus isabellinus

Barrow Island Wallaroo, Barrow Island Euro [89262] Vulnerable Species or species habitat
likely to occur within area

Perameles bougainville bougainville

Western Barred Bandicoot (Shark Bay) [66631] Endangered Species or species habitat
known to occur within area

Petrogale concinna monastria

Nabarlek (Kimberley) [87607] Endangered Species or species habitat
known to occur within area

Petrogale lateralis lateralis

Black-flanked Rock-wallaby, Moororong, Black-footed Endangered Species or species habitat
Rock Wallaby [66647] known to occur within area

Phascogale tapoatafa kimberleyensis

Kimberley brush-tailed phascogale, Brush-tailed Vulnerable Species or species habitat
Phascogale (Kimberley) [88453] known to occur within area

Pipistrellus murrayi
Christmas Island Pipistrelle [64383] Critically Endangered Species or species habitat
known to occur within area

Pteropus natalis
Christmas Island Flying-fox, Christmas Island Fruit-bat Critically Endangered Roosting known to occur
[87611] within area
Rhinonicteris aurantia (Pilbara form)
Pilbara Leaf-nosed Bat [82790] Vulnerable Species or species habitat
known to occur within area

Saccolaimus saccolaimus nudicluniatus

Bare-rumped Sheath-tailed Bat, Bare-rumped Vulnerable Species or species habitat
Sheathtail Bat [66889] likely to occur within area

Xeromys myoides
Water Mouse, False Water Rat, Yirrkoo [66] Vulnerable Species or species habitat
may occur within area

Plants
Asplenium listeri
Christmas Island Spleenwort [65865] Critically Endangered Species or species habitat
known to occur within area

Keraudrenia exastia
Fringed Keraudrenia [66301] Critically Endangered Species or species habitat
known to occur within area

Pneumatopteris truncata
fern [68812] Critically Endangered Species or species habitat
known to occur within area
Name Status Type of Presence
Tectaria devexa
[14767] Endangered Species or species habitat
likely to occur within area

Reptiles
Aipysurus apraefrontalis
Short-nosed Seasnake [1115] Critically Endangered Species or species habitat
known to occur within area

Aipysurus foliosquama
Leaf-scaled Seasnake [1118] Critically Endangered Species or species habitat
known to occur within area

Caretta caretta
Loggerhead Turtle [1763] Endangered Breeding known to occur
within area
Chelonia mydas
Green Turtle [1765] Vulnerable Breeding known to occur
within area
Cryptoblepharus egeriae
Christmas Island Blue-tailed Skink, Blue-tailed Snake- Critically Endangered Species or species habitat
eyed Skink [1526] likely to occur within area

Ctenotus zastictus
Hamelin Ctenotus [25570] Vulnerable Species or species habitat
known to occur within area

Cyrtodactylus sadleiri
Christmas Island Giant Gecko [86865] Endangered Species or species habitat
known to occur within area

Dermochelys coriacea
Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Foraging, feeding or related
behaviour known to occur
within area
Egernia stokesii badia
Western Spiny-tailed Skink, Baudin Island Spiny-tailed Endangered Species or species habitat
Skink [64483] known to occur within area

Emoia nativitatis
Christmas Island Forest Skink, Christmas Island Critically Endangered Species or species habitat
Whiptail-skink [1400] known to occur within area

Eretmochelys imbricata
Hawksbill Turtle [1766] Vulnerable Breeding known to occur
within area
Lepidochelys olivacea
Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Foraging, feeding or related
behaviour known to occur
within area
Lepidodactylus listeri
Christmas Island Gecko, Lister's Gecko [1711] Critically Endangered Species or species habitat
known to occur within area

Liasis olivaceus barroni

Olive Python (Pilbara subspecies) [66699] Vulnerable Species or species habitat
known to occur within area

Natator depressus
Flatback Turtle [59257] Vulnerable Breeding known to occur
within area
Ramphotyphlops exocoeti
Christmas Island Blind Snake, Christmas Island Pink Vulnerable Species or species habitat
Blind Snake [1262] likely to occur within area

Sharks
Carcharias taurus (west coast population)
Grey Nurse Shark (west coast population) [68752] Vulnerable Species or species habitat
known to occur within area

Carcharodon carcharias
White Shark, Great White Shark [64470] Vulnerable Species or species habitat
known to occur
Name Status Type of Presence
within area
Glyphis garricki
Northern River Shark, New Guinea River Shark Endangered Breeding likely to occur
[82454] within area
Glyphis glyphis
Speartooth Shark [82453] Critically Endangered Species or species habitat
may occur within area

Pristis clavata
Dwarf Sawfish, Queensland Sawfish [68447] Vulnerable Breeding known to occur
within area
Pristis pristis
Freshwater Sawfish, Largetooth Sawfish, River Vulnerable Species or species habitat
Sawfish, Leichhardt's Sawfish, Northern Sawfish known to occur within area
[60756]
Pristis zijsron
Green Sawfish, Dindagubba, Narrowsnout Sawfish Vulnerable Breeding known to occur
[68442] within area
Rhincodon typus
Whale Shark [66680] Vulnerable Foraging, feeding or related
behaviour known to occur
within area

Listed Migratory Species [ Resource Information ]

* Species is listed under a different scientific name on the EPBC Act - Threatened Species list.
Name Threatened Type of Presence
Migratory Marine Birds
Anous stolidus
Common Noddy [825] Breeding known to occur
within area
Apus pacificus
Fork-tailed Swift [678] Species or species habitat
likely to occur within area

Ardenna carneipes
Flesh-footed Shearwater, Fleshy-footed Shearwater Foraging, feeding or related
[82404] behaviour likely to occur
within area
Ardenna pacifica
Wedge-tailed Shearwater [84292] Breeding known to occur
within area
Calonectris leucomelas
Streaked Shearwater [1077] Species or species habitat
known to occur within area

Diomedea amsterdamensis
Amsterdam Albatross [64405] Endangered Species or species habitat
likely to occur within area

Diomedea epomophora
Southern Royal Albatross [89221] Vulnerable Species or species habitat
may occur within area

Diomedea exulans
Wandering Albatross [89223] Vulnerable Species or species habitat
may occur within area

Fregata andrewsi
Christmas Island Frigatebird, Andrew's Frigatebird Endangered Breeding known to occur
[1011] within area
Fregata ariel
Lesser Frigatebird, Least Frigatebird [1012] Breeding known to occur
within area
Fregata minor
Great Frigatebird, Greater Frigatebird [1013] Breeding known to occur
within area
Hydroprogne caspia
Caspian Tern [808] Breeding known to occur
within area
Macronectes giganteus
Southern Giant-Petrel, Southern Giant Petrel [1060] Endangered Species or species habitat
may occur within
Name Threatened Type of Presence
area
Macronectes halli
Northern Giant Petrel [1061] Vulnerable Species or species habitat
may occur within area

Onychoprion anaethetus
Bridled Tern [82845] Breeding known to occur
within area
Phaethon lepturus
White-tailed Tropicbird [1014] Breeding known to occur
within area
Phaethon rubricauda
Red-tailed Tropicbird [994] Breeding known to occur
within area
Sterna dougallii
Roseate Tern [817] Breeding known to occur
within area
Sternula albifrons
Little Tern [82849] Breeding known to occur
within area
Sula dactylatra
Masked Booby [1021] Breeding known to occur
within area
Sula leucogaster
Brown Booby [1022] Breeding known to occur
within area
Sula sula
Red-footed Booby [1023] Breeding known to occur
within area
Thalassarche carteri
Indian Yellow-nosed Albatross [64464] Vulnerable Foraging, feeding or related
behaviour may occur within
area
Thalassarche cauta
Tasmanian Shy Albatross [89224] Vulnerable* Species or species habitat
may occur within area

Thalassarche impavida
Campbell Albatross, Campbell Black-browed Albatross Vulnerable Species or species habitat
[64459] may occur within area

Thalassarche melanophris
Black-browed Albatross [66472] Vulnerable Species or species habitat
may occur within area

Thalassarche steadi
White-capped Albatross [64462] Vulnerable* Foraging, feeding or related
behaviour likely to occur
within area
Migratory Marine Species
Anoxypristis cuspidata
Narrow Sawfish, Knifetooth Sawfish [68448] Species or species habitat
known to occur within area

Balaena glacialis australis

Southern Right Whale [75529] Endangered* Species or species habitat
likely to occur within area

Balaenoptera bonaerensis
Antarctic Minke Whale, Dark-shoulder Minke Whale Species or species habitat
[67812] likely to occur within area

Balaenoptera borealis
Sei Whale [34] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Balaenoptera edeni
Bryde's Whale [35] Species or species habitat
likely to occur within area

Balaenoptera musculus
Blue Whale [36] Endangered Migration route known to
Name Threatened Type of Presence
occur within area
Balaenoptera physalus
Fin Whale [37] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Carcharodon carcharias
White Shark, Great White Shark [64470] Vulnerable Species or species habitat
known to occur within area

Caretta caretta
Loggerhead Turtle [1763] Endangered Breeding known to occur
within area
Chelonia mydas
Green Turtle [1765] Vulnerable Breeding known to occur
within area
Crocodylus porosus
Salt-water Crocodile, Estuarine Crocodile [1774] Species or species habitat
likely to occur within area

Dermochelys coriacea
Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Foraging, feeding or related
behaviour known to occur
within area
Dugong dugon
Dugong [28] Breeding known to occur
within area
Eretmochelys imbricata
Hawksbill Turtle [1766] Vulnerable Breeding known to occur
within area
Isurus oxyrinchus
Shortfin Mako, Mako Shark [79073] Species or species habitat
likely to occur within area

Isurus paucus
Longfin Mako [82947] Species or species habitat
likely to occur within area

Lamna nasus
Porbeagle, Mackerel Shark [83288] Species or species habitat
may occur within area

Lepidochelys olivacea
Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Foraging, feeding or related
behaviour known to occur
within area
Manta alfredi
Reef Manta Ray, Coastal Manta Ray, Inshore Manta Species or species habitat
Ray, Prince Alfred's Ray, Resident Manta Ray [84994] known to occur within area

Manta birostris
Giant Manta Ray, Chevron Manta Ray, Pacific Manta Species or species habitat
Ray, Pelagic Manta Ray, Oceanic Manta Ray [84995] known to occur within area

Megaptera novaeangliae
Humpback Whale [38] Vulnerable Breeding known to occur
within area
Natator depressus
Flatback Turtle [59257] Vulnerable Breeding known to occur
within area
Orcaella heinsohni
Australian Snubfin Dolphin [81322] Species or species habitat
known to occur within area

Orcinus orca
Killer Whale, Orca [46] Species or species habitat
may occur within area

Physeter macrocephalus
Sperm Whale [59] Species or species habitat
may occur within area

Pristis clavata
Dwarf Sawfish, Queensland Sawfish [68447] Vulnerable Breeding known to occur
Name Threatened Type of Presence
within area
Pristis pristis
Freshwater Sawfish, Largetooth Sawfish, River Vulnerable Species or species habitat
Sawfish, Leichhardt's Sawfish, Northern Sawfish known to occur within area
[60756]
Pristis zijsron
Green Sawfish, Dindagubba, Narrowsnout Sawfish Vulnerable Breeding known to occur
[68442] within area
Rhincodon typus
Whale Shark [66680] Vulnerable Foraging, feeding or related
behaviour known to occur
within area
Sousa chinensis
Indo-Pacific Humpback Dolphin [50] Breeding known to occur
within area
Tursiops aduncus (Arafura/Timor Sea populations)
Spotted Bottlenose Dolphin (Arafura/Timor Sea Species or species habitat
populations) [78900] known to occur within area

Migratory Terrestrial Species

Cecropis daurica
Red-rumped Swallow [80610] Species or species habitat
known to occur within area

Cuculus optatus
Oriental Cuckoo, Horsfield's Cuckoo [86651] Species or species habitat
known to occur within area

Hirundo rustica
Barn Swallow [662] Species or species habitat
known to occur within area

Motacilla cinerea
Grey Wagtail [642] Species or species habitat
known to occur within area

Motacilla flava
Yellow Wagtail [644] Species or species habitat
known to occur within area

Rhipidura rufifrons
Rufous Fantail [592] Species or species habitat
known to occur within area

Migratory Wetlands Species

Acrocephalus orientalis
Oriental Reed-Warbler [59570] Species or species habitat
known to occur within area

Actitis hypoleucos
Common Sandpiper [59309] Species or species habitat
known to occur within area

Arenaria interpres
Ruddy Turnstone [872] Roosting known to occur
within area
Calidris acuminata
Sharp-tailed Sandpiper [874] Roosting known to occur
within area
Calidris alba
Sanderling [875] Roosting known to occur
within area
Calidris canutus
Red Knot, Knot [855] Endangered Species or species habitat
known to occur within area

Calidris ferruginea
Curlew Sandpiper [856] Critically Endangered Species or species habitat
known to occur within area

Calidris melanotos
Pectoral Sandpiper [858] Species or species
Name Threatened Type of Presence
habitat known to occur
within area
Calidris ruficollis
Red-necked Stint [860] Roosting known to occur
within area
Calidris tenuirostris
Great Knot [862] Critically Endangered Roosting known to occur
within area
Charadrius bicinctus
Double-banded Plover [895] Roosting known to occur
within area
Charadrius leschenaultii
Greater Sand Plover, Large Sand Plover [877] Vulnerable Roosting known to occur
within area
Charadrius mongolus
Lesser Sand Plover, Mongolian Plover [879] Endangered Roosting known to occur
within area
Charadrius veredus
Oriental Plover, Oriental Dotterel [882] Roosting known to occur
within area
Gallinago megala
Swinhoe's Snipe [864] Roosting likely to occur
within area
Gallinago stenura
Pin-tailed Snipe [841] Roosting likely to occur
within area
Glareola maldivarum
Oriental Pratincole [840] Roosting known to occur
within area
Limicola falcinellus
Broad-billed Sandpiper [842] Roosting known to occur
within area
Limnodromus semipalmatus
Asian Dowitcher [843] Roosting known to occur
within area
Limosa lapponica
Bar-tailed Godwit [844] Species or species habitat
known to occur within area

Limosa limosa
Black-tailed Godwit [845] Roosting known to occur
within area
Numenius madagascariensis
Eastern Curlew, Far Eastern Curlew [847] Critically Endangered Species or species habitat
known to occur within area

Numenius minutus
Little Curlew, Little Whimbrel [848] Roosting known to occur
within area
Numenius phaeopus
Whimbrel [849] Roosting known to occur
within area
Pandion haliaetus
Osprey [952] Breeding known to occur
within area
Philomachus pugnax
Ruff (Reeve) [850] Roosting known to occur
within area
Pluvialis fulva
Pacific Golden Plover [25545] Roosting known to occur
within area
Pluvialis squatarola
Grey Plover [865] Roosting known to occur
within area
Thalasseus bergii
Crested Tern [83000] Breeding known to occur
within area
Tringa brevipes
Grey-tailed Tattler [851] Roosting known to occur
within area
Tringa glareola
Wood Sandpiper [829] Roosting known to occur
Name Threatened Type of Presence
within area
Tringa nebularia
Common Greenshank, Greenshank [832] Species or species habitat
known to occur within area

Tringa stagnatilis
Marsh Sandpiper, Little Greenshank [833] Roosting known to occur
within area
Tringa totanus
Common Redshank, Redshank [835] Roosting known to occur
within area
Xenus cinereus
Terek Sandpiper [59300] Roosting known to occur
within area

Other Matters Protected by the EPBC Act

Commonwealth Land [ Resource Information ]
The Commonwealth area listed below may indicate the presence of Commonwealth land in this vicinity. Due to
the unreliability of the data source, all proposals should be checked as to whether it impacts on a
Commonwealth area, before making a definitive decision. Contact the State or Territory government land
department for further information.
Name
Commonwealth Land -
Commonwealth Land - Christmas Island National Park
Defence - BROOME TRAINING DEPOT
Defence - EXMOUTH ADMIN & HF TRANSMITTING
Defence - EXMOUTH VLF TRANSMITTER STATION
Defence - LEARMONTH RADAR SITE - VLAMING HEAD EXMOUTH
Defence - NORFORCE DEPOT - DERBY
Defence - RAAF BASE CURTIN
Defence - YAMPI SOUND TRAINING AREA

Commonwealth Heritage Places [ Resource Information ]

Name State Status
Natural
Ashmore Reef National Nature Reserve EXT Listed place
Christmas Island Natural Areas EXT Listed place
Mermaid Reef - Rowley Shoals WA Listed place
Ningaloo Marine Area - Commonwealth Waters WA Listed place
Scott Reef and Surrounds - Commonwealth Area EXT Listed place
Yampi Defence Area WA Listed place
Indigenous
Oombalai Area WA Within listed place
Historic
Administrators House Precinct EXT Listed place
Bungalow 702 EXT Listed place
Drumsite Industrial Area EXT Listed place
HMAS Sydney II and HSK Kormoran Shipwreck Sites EXT Listed place
Industrial and Administrative Group EXT Listed place
Malay Kampong Group EXT Listed place
Malay Kampong Precinct EXT Listed place
Phosphate Hill Historic Area EXT Listed place
Poon Saan Group EXT Listed place
Settlement Christmas Island EXT Listed place
South Point Settlement Remains EXT Listed place

Listed Marine Species [ Resource Information ]

* Species is listed under a different scientific name on the EPBC Act - Threatened Species list.
Name Threatened Type of Presence
Birds
Name Threatened Type of Presence
Acrocephalus orientalis
Oriental Reed-Warbler [59570] Species or species habitat
known to occur within area

Actitis hypoleucos
Common Sandpiper [59309] Species or species habitat
known to occur within area

Anous minutus
Black Noddy [824] Breeding known to occur
within area
Anous stolidus
Common Noddy [825] Breeding known to occur
within area
Anous tenuirostris melanops
Australian Lesser Noddy [26000] Vulnerable Breeding known to occur
within area
Anseranas semipalmata
Magpie Goose [978] Species or species habitat
may occur within area

Apus pacificus
Fork-tailed Swift [678] Species or species habitat
likely to occur within area

Ardea alba
Great Egret, White Egret [59541] Breeding known to occur
within area
Ardea ibis
Cattle Egret [59542] Species or species habitat
may occur within area

Arenaria interpres
Ruddy Turnstone [872] Roosting known to occur
within area
Calidris acuminata
Sharp-tailed Sandpiper [874] Roosting known to occur
within area
Calidris alba
Sanderling [875] Roosting known to occur
within area
Calidris canutus
Red Knot, Knot [855] Endangered Species or species habitat
known to occur within area

Calidris ferruginea
Curlew Sandpiper [856] Critically Endangered Species or species habitat
known to occur within area

Calidris melanotos
Pectoral Sandpiper [858] Species or species habitat
known to occur within area

Calidris ruficollis
Red-necked Stint [860] Roosting known to occur
within area
Calidris tenuirostris
Great Knot [862] Critically Endangered Roosting known to occur
within area
Calonectris leucomelas
Streaked Shearwater [1077] Species or species habitat
known to occur within area

Catharacta skua
Great Skua [59472] Species or species habitat
may occur within area

Charadrius bicinctus
Double-banded Plover [895] Roosting known to occur
within area
Charadrius leschenaultii
Greater Sand Plover, Large Sand Plover [877] Vulnerable Roosting known to occur
within area
Name Threatened Type of Presence
Charadrius mongolus
Lesser Sand Plover, Mongolian Plover [879] Endangered Roosting known to occur
within area
Charadrius ruficapillus
Red-capped Plover [881] Roosting known to occur
within area
Charadrius veredus
Oriental Plover, Oriental Dotterel [882] Roosting known to occur
within area
Chrysococcyx osculans
Black-eared Cuckoo [705] Species or species habitat
known to occur within area

Diomedea amsterdamensis
Amsterdam Albatross [64405] Endangered Species or species habitat
likely to occur within area

Diomedea epomophora
Southern Royal Albatross [89221] Vulnerable Species or species habitat
may occur within area

Diomedea exulans
Wandering Albatross [89223] Vulnerable Species or species habitat
may occur within area

Fregata andrewsi
Christmas Island Frigatebird, Andrew's Frigatebird Endangered Breeding known to occur
[1011] within area
Fregata ariel
Lesser Frigatebird, Least Frigatebird [1012] Breeding known to occur
within area
Fregata minor
Great Frigatebird, Greater Frigatebird [1013] Breeding known to occur
within area
Gallinago megala
Swinhoe's Snipe [864] Roosting likely to occur
within area
Gallinago stenura
Pin-tailed Snipe [841] Roosting likely to occur
within area
Glareola maldivarum
Oriental Pratincole [840] Roosting known to occur
within area
Haliaeetus leucogaster
White-bellied Sea-Eagle [943] Species or species habitat
known to occur within area

Heteroscelus brevipes
Grey-tailed Tattler [59311] Roosting known to occur
within area
Himantopus himantopus
Pied Stilt, Black-winged Stilt [870] Roosting known to occur
within area
Hirundo daurica
Red-rumped Swallow [59480] Species or species habitat
known to occur within area

Hirundo rustica
Barn Swallow [662] Species or species habitat
known to occur within area

Larus novaehollandiae
Silver Gull [810] Breeding known to occur
within area
Larus pacificus
Pacific Gull [811] Breeding known to occur
within area
Limicola falcinellus
Broad-billed Sandpiper [842] Roosting known to occur
within area
Limnodromus semipalmatus
Asian Dowitcher [843] Roosting known to occur
Name Threatened Type of Presence
within area
Limosa lapponica
Bar-tailed Godwit [844] Species or species habitat
known to occur within area

Limosa limosa
Black-tailed Godwit [845] Roosting known to occur
within area
Macronectes giganteus
Southern Giant-Petrel, Southern Giant Petrel [1060] Endangered Species or species habitat
may occur within area

Macronectes halli
Northern Giant Petrel [1061] Vulnerable Species or species habitat
may occur within area

Merops ornatus
Rainbow Bee-eater [670] Species or species habitat
may occur within area

Motacilla cinerea
Grey Wagtail [642] Species or species habitat
known to occur within area

Motacilla flava
Yellow Wagtail [644] Species or species habitat
known to occur within area

Numenius madagascariensis
Eastern Curlew, Far Eastern Curlew [847] Critically Endangered Species or species habitat
known to occur within area

Numenius minutus
Little Curlew, Little Whimbrel [848] Roosting known to occur
within area
Numenius phaeopus
Whimbrel [849] Roosting known to occur
within area
Pandion haliaetus
Osprey [952] Breeding known to occur
within area
Papasula abbotti
Abbott's Booby [59297] Endangered Species or species habitat
known to occur within area

Phaethon lepturus
White-tailed Tropicbird [1014] Breeding known to occur
within area
Phaethon lepturus fulvus
Christmas Island White-tailed Tropicbird, Golden Endangered Breeding likely to occur
Bosunbird [26021] within area
Phaethon rubricauda
Red-tailed Tropicbird [994] Breeding known to occur
within area
Philomachus pugnax
Ruff (Reeve) [850] Roosting known to occur
within area
Pluvialis fulva
Pacific Golden Plover [25545] Roosting known to occur
within area
Pluvialis squatarola
Grey Plover [865] Roosting known to occur
within area
Pterodroma macroptera
Great-winged Petrel [1035] Foraging, feeding or related
behaviour known to occur
within area
Pterodroma mollis
Soft-plumaged Petrel [1036] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Name Threatened Type of Presence
Puffinus assimilis
Little Shearwater [59363] Foraging, feeding or related
behaviour known to occur
within area
Puffinus carneipes
Flesh-footed Shearwater, Fleshy-footed Shearwater Foraging, feeding or related
[1043] behaviour likely to occur
within area
Puffinus pacificus
Wedge-tailed Shearwater [1027] Breeding known to occur
within area
Recurvirostra novaehollandiae
Red-necked Avocet [871] Roosting known to occur
within area
Rhipidura rufifrons
Rufous Fantail [592] Species or species habitat
known to occur within area

Rostratula benghalensis (sensu lato)

Painted Snipe [889] Endangered* Species or species habitat
known to occur within area

Sterna albifrons
Little Tern [813] Breeding known to occur
within area
Sterna anaethetus
Bridled Tern [814] Breeding known to occur
within area
Sterna bengalensis
Lesser Crested Tern [815] Breeding known to occur
within area
Sterna bergii
Crested Tern [816] Breeding known to occur
within area
Sterna caspia
Caspian Tern [59467] Breeding known to occur
within area
Sterna dougallii
Roseate Tern [817] Breeding known to occur
within area
Sterna fuscata
Sooty Tern [794] Breeding known to occur
within area
Sterna nereis
Fairy Tern [796] Breeding known to occur
within area
Stiltia isabella
Australian Pratincole [818] Roosting known to occur
within area
Sula dactylatra
Masked Booby [1021] Breeding known to occur
within area
Sula leucogaster
Brown Booby [1022] Breeding known to occur
within area
Sula sula
Red-footed Booby [1023] Breeding known to occur
within area
Thalassarche carteri
Indian Yellow-nosed Albatross [64464] Vulnerable Foraging, feeding or related
behaviour may occur within
area
Thalassarche cauta
Tasmanian Shy Albatross [89224] Vulnerable* Species or species habitat
may occur within area

Thalassarche impavida
Campbell Albatross, Campbell Black-browed Albatross Vulnerable Species or species habitat
[64459] may occur within area

Thalassarche melanophris
Black-browed Albatross [66472] Vulnerable Species or species
Name Threatened Type of Presence
habitat may occur within
area
Thalassarche steadi
White-capped Albatross [64462] Vulnerable* Foraging, feeding or related
behaviour likely to occur
within area
Thinornis rubricollis
Hooded Plover [59510] Species or species habitat
known to occur within area

Tringa glareola
Wood Sandpiper [829] Roosting known to occur
within area
Tringa nebularia
Common Greenshank, Greenshank [832] Species or species habitat
known to occur within area

Tringa stagnatilis
Marsh Sandpiper, Little Greenshank [833] Roosting known to occur
within area
Tringa totanus
Common Redshank, Redshank [835] Roosting known to occur
within area
Xenus cinereus
Terek Sandpiper [59300] Roosting known to occur
within area
Fish
Acentronura australe
Southern Pygmy Pipehorse [66185] Species or species habitat
may occur within area

Acentronura larsonae
Helen's Pygmy Pipehorse [66186] Species or species habitat
may occur within area

Bhanotia fasciolata
Corrugated Pipefish, Barbed Pipefish [66188] Species or species habitat
may occur within area

Bulbonaricus brauni
Braun's Pughead Pipefish, Pug-headed Pipefish Species or species habitat
[66189] may occur within area

Campichthys galei
Gale's Pipefish [66191] Species or species habitat
may occur within area

Campichthys tricarinatus
Three-keel Pipefish [66192] Species or species habitat
may occur within area

Choeroichthys brachysoma
Pacific Short-bodied Pipefish, Short-bodied Pipefish Species or species habitat
[66194] may occur within area

Choeroichthys latispinosus
Muiron Island Pipefish [66196] Species or species habitat
may occur within area

Choeroichthys sculptus
Sculptured Pipefish [66197] Species or species habitat
may occur within area

Choeroichthys suillus
Pig-snouted Pipefish [66198] Species or species habitat
may occur within area

Corythoichthys amplexus
Fijian Banded Pipefish, Brown-banded Pipefish Species or species habitat
[66199] may occur within area

Corythoichthys flavofasciatus
Reticulate Pipefish, Yellow-banded Pipefish, Species or species
Name Threatened Type of Presence
Network Pipefish [66200] habitat may occur within
area
Corythoichthys haematopterus
Reef-top Pipefish [66201] Species or species habitat
may occur within area

Corythoichthys intestinalis
Australian Messmate Pipefish, Banded Pipefish Species or species habitat
[66202] may occur within area

Corythoichthys schultzi
Schultz's Pipefish [66205] Species or species habitat
may occur within area

Cosmocampus banneri
Roughridge Pipefish [66206] Species or species habitat
may occur within area

Cosmocampus maxweberi
Maxweber's Pipefish [66209] Species or species habitat
may occur within area

Doryrhamphus baldwini
Redstripe Pipefish [66718] Species or species habitat
may occur within area

Doryrhamphus dactyliophorus
Banded Pipefish, Ringed Pipefish [66210] Species or species habitat
may occur within area

Doryrhamphus excisus
Bluestripe Pipefish, Indian Blue-stripe Pipefish, Pacific Species or species habitat
Blue-stripe Pipefish [66211] may occur within area

Doryrhamphus janssi
Cleaner Pipefish, Janss' Pipefish [66212] Species or species habitat
may occur within area

Doryrhamphus multiannulatus
Many-banded Pipefish [66717] Species or species habitat
may occur within area

Doryrhamphus negrosensis
Flagtail Pipefish, Masthead Island Pipefish [66213] Species or species habitat
may occur within area

Festucalex cinctus
Girdled Pipefish [66214] Species or species habitat
may occur within area

Festucalex scalaris
Ladder Pipefish [66216] Species or species habitat
may occur within area

Filicampus tigris
Tiger Pipefish [66217] Species or species habitat
may occur within area

Halicampus brocki
Brock's Pipefish [66219] Species or species habitat
may occur within area

Halicampus dunckeri
Red-hair Pipefish, Duncker's Pipefish [66220] Species or species habitat
may occur within area

Halicampus grayi
Mud Pipefish, Gray's Pipefish [66221] Species or species habitat
may occur within area

Halicampus macrorhynchus
Whiskered Pipefish, Ornate Pipefish [66222] Species or species habitat
may occur within
Name Threatened Type of Presence
area
Halicampus mataafae
Samoan Pipefish [66223] Species or species habitat
may occur within area

Halicampus nitidus
Glittering Pipefish [66224] Species or species habitat
may occur within area

Halicampus spinirostris
Spiny-snout Pipefish [66225] Species or species habitat
may occur within area

Haliichthys taeniophorus
Ribboned Pipehorse, Ribboned Seadragon [66226] Species or species habitat
may occur within area

Hippichthys cyanospilos
Blue-speckled Pipefish, Blue-spotted Pipefish [66228] Species or species habitat
may occur within area

Hippichthys heptagonus
Madura Pipefish, Reticulated Freshwater Pipefish Species or species habitat
[66229] may occur within area

Hippichthys parvicarinatus
Short-keel Pipefish, Short-keeled Pipefish [66230] Species or species habitat
may occur within area

Hippichthys penicillus
Beady Pipefish, Steep-nosed Pipefish [66231] Species or species habitat
may occur within area

Hippichthys spicifer
Belly-barred Pipefish, Banded Freshwater Pipefish Species or species habitat
[66232] may occur within area

Hippocampus angustus
Western Spiny Seahorse, Narrow-bellied Seahorse Species or species habitat
[66234] may occur within area

Hippocampus breviceps
Short-head Seahorse, Short-snouted Seahorse Species or species habitat
[66235] may occur within area

Hippocampus histrix
Spiny Seahorse, Thorny Seahorse [66236] Species or species habitat
may occur within area

Hippocampus kuda
Spotted Seahorse, Yellow Seahorse [66237] Species or species habitat
may occur within area

Hippocampus planifrons
Flat-face Seahorse [66238] Species or species habitat
may occur within area

Hippocampus spinosissimus
Hedgehog Seahorse [66239] Species or species habitat
may occur within area

Hippocampus subelongatus
West Australian Seahorse [66722] Species or species habitat
may occur within area

Hippocampus trimaculatus
Three-spot Seahorse, Low-crowned Seahorse, Flat- Species or species habitat
faced Seahorse [66720] may occur within area

Lissocampus fatiloquus
Prophet's Pipefish [66250] Species or species habitat
may occur within area
Name Threatened Type of Presence
Maroubra perserrata
Sawtooth Pipefish [66252] Species or species habitat
may occur within area

Micrognathus brevirostris
thorntail Pipefish, Thorn-tailed Pipefish [66254] Species or species habitat
may occur within area

Micrognathus micronotopterus
Tidepool Pipefish [66255] Species or species habitat
may occur within area

Mitotichthys meraculus
Western Crested Pipefish [66259] Species or species habitat
may occur within area

Nannocampus subosseus
Bonyhead Pipefish, Bony-headed Pipefish [66264] Species or species habitat
may occur within area

Phoxocampus belcheri
Black Rock Pipefish [66719] Species or species habitat
may occur within area

Phycodurus eques
Leafy Seadragon [66267] Species or species habitat
may occur within area

Phyllopteryx taeniolatus
Common Seadragon, Weedy Seadragon [66268] Species or species habitat
may occur within area

Pugnaso curtirostris
Pugnose Pipefish, Pug-nosed Pipefish [66269] Species or species habitat
may occur within area

Solegnathus hardwickii
Pallid Pipehorse, Hardwick's Pipehorse [66272] Species or species habitat
may occur within area

Solegnathus lettiensis
Gunther's Pipehorse, Indonesian Pipefish [66273] Species or species habitat
may occur within area

Solenostomus cyanopterus
Robust Ghostpipefish, Blue-finned Ghost Pipefish, Species or species habitat
[66183] may occur within area

Stigmatopora argus
Spotted Pipefish, Gulf Pipefish, Peacock Pipefish Species or species habitat
[66276] may occur within area

Stigmatopora nigra
Widebody Pipefish, Wide-bodied Pipefish, Black Species or species habitat
Pipefish [66277] may occur within area

Syngnathoides biaculeatus
Double-end Pipehorse, Double-ended Pipehorse, Species or species habitat
Alligator Pipefish [66279] may occur within area

Trachyrhamphus bicoarctatus
Bentstick Pipefish, Bend Stick Pipefish, Short-tailed Species or species habitat
Pipefish [66280] may occur within area

Trachyrhamphus longirostris
Straightstick Pipefish, Long-nosed Pipefish, Straight Species or species habitat
Stick Pipefish [66281] may occur within area

Urocampus carinirostris
Hairy Pipefish [66282] Species or species habitat
may occur within area
Name Threatened Type of Presence
Vanacampus margaritifer
Mother-of-pearl Pipefish [66283] Species or species habitat
may occur within area

Mammals
Dugong dugon
Dugong [28] Breeding known to occur
within area
Reptiles
Acalyptophis peronii
Horned Seasnake [1114] Species or species habitat
may occur within area

Aipysurus apraefrontalis
Short-nosed Seasnake [1115] Critically Endangered Species or species habitat
known to occur within area

Aipysurus duboisii
Dubois' Seasnake [1116] Species or species habitat
may occur within area

Aipysurus eydouxii
Spine-tailed Seasnake [1117] Species or species habitat
may occur within area

Aipysurus foliosquama
Leaf-scaled Seasnake [1118] Critically Endangered Species or species habitat
known to occur within area

Aipysurus fuscus
Dusky Seasnake [1119] Species or species habitat
known to occur within area

Aipysurus laevis
Olive Seasnake [1120] Species or species habitat
may occur within area

Aipysurus pooleorum
Shark Bay Seasnake [66061] Species or species habitat
may occur within area

Aipysurus tenuis
Brown-lined Seasnake [1121] Species or species habitat
may occur within area

Astrotia stokesii
Stokes' Seasnake [1122] Species or species habitat
may occur within area

Caretta caretta
Loggerhead Turtle [1763] Endangered Breeding known to occur
within area
Chelonia mydas
Green Turtle [1765] Vulnerable Breeding known to occur
within area
Crocodylus johnstoni
Freshwater Crocodile, Johnston's Crocodile, Species or species habitat
Johnston's River Crocodile [1773] may occur within area

Crocodylus porosus
Salt-water Crocodile, Estuarine Crocodile [1774] Species or species habitat
likely to occur within area

Dermochelys coriacea
Leatherback Turtle, Leathery Turtle, Luth [1768] Endangered Foraging, feeding or related
behaviour known to occur
within area
Disteira kingii
Spectacled Seasnake [1123] Species or species habitat
may occur within area

Disteira major
Olive-headed Seasnake [1124] Species or species
Name Threatened Type of Presence
habitat may occur within
area
Emydocephalus annulatus
Turtle-headed Seasnake [1125] Species or species habitat
may occur within area

Enhydrina schistosa
Beaked Seasnake [1126] Species or species habitat
may occur within area

Ephalophis greyi
North-western Mangrove Seasnake [1127] Species or species habitat
may occur within area

Eretmochelys imbricata
Hawksbill Turtle [1766] Vulnerable Breeding known to occur
within area
Hydrelaps darwiniensis
Black-ringed Seasnake [1100] Species or species habitat
may occur within area

Hydrophis atriceps
Black-headed Seasnake [1101] Species or species habitat
may occur within area

Hydrophis coggeri
Slender-necked Seasnake [25925] Species or species habitat
may occur within area

Hydrophis czeblukovi
Fine-spined Seasnake [59233] Species or species habitat
may occur within area

Hydrophis elegans
Elegant Seasnake [1104] Species or species habitat
may occur within area

Hydrophis inornatus
Plain Seasnake [1107] Species or species habitat
may occur within area

Hydrophis mcdowelli
null [25926] Species or species habitat
may occur within area

Hydrophis ornatus
Spotted Seasnake, Ornate Reef Seasnake [1111] Species or species habitat
may occur within area

Hydrophis pacificus
Large-headed Seasnake, Pacific Seasnake [1112] Species or species habitat
may occur within area

Lapemis hardwickii
Spine-bellied Seasnake [1113] Species or species habitat
may occur within area

Lepidochelys olivacea
Olive Ridley Turtle, Pacific Ridley Turtle [1767] Endangered Foraging, feeding or related
behaviour known to occur
within area
Natator depressus
Flatback Turtle [59257] Vulnerable Breeding known to occur
within area
Parahydrophis mertoni
Northern Mangrove Seasnake [1090] Species or species habitat
may occur within area

Pelamis platurus
Yellow-bellied Seasnake [1091] Species or species habitat
may occur within area
Whales and other Cetaceans [ Resource Information ]
Name Status Type of Presence
Mammals
Balaenoptera acutorostrata
Minke Whale [33] Species or species habitat
may occur within area

Balaenoptera bonaerensis
Antarctic Minke Whale, Dark-shoulder Minke Whale Species or species habitat
[67812] likely to occur within area

Balaenoptera borealis
Sei Whale [34] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Balaenoptera edeni
Bryde's Whale [35] Species or species habitat
likely to occur within area

Balaenoptera musculus
Blue Whale [36] Endangered Migration route known to
occur within area
Balaenoptera physalus
Fin Whale [37] Vulnerable Foraging, feeding or related
behaviour likely to occur
within area
Delphinus delphis
Common Dophin, Short-beaked Common Dolphin [60] Species or species habitat
may occur within area

Eubalaena australis
Southern Right Whale [40] Endangered Species or species habitat
likely to occur within area

Feresa attenuata
Pygmy Killer Whale [61] Species or species habitat
may occur within area

Globicephala macrorhynchus
Short-finned Pilot Whale [62] Species or species habitat
may occur within area

Globicephala melas
Long-finned Pilot Whale [59282] Species or species habitat
may occur within area

Grampus griseus
Risso's Dolphin, Grampus [64] Species or species habitat
may occur within area

Indopacetus pacificus
Longman's Beaked Whale [72] Species or species habitat
may occur within area

Kogia breviceps
Pygmy Sperm Whale [57] Species or species habitat
may occur within area

Kogia simus
Dwarf Sperm Whale [58] Species or species habitat
may occur within area

Lagenodelphis hosei
Fraser's Dolphin, Sarawak Dolphin [41] Species or species habitat
may occur within area

Megaptera novaeangliae
Humpback Whale [38] Vulnerable Breeding known to occur
within area
Mesoplodon densirostris
Blainville's Beaked Whale, Dense-beaked Whale [74] Species or species habitat
may occur within area
Name Status Type of Presence
Mesoplodon ginkgodens
Gingko-toothed Beaked Whale, Gingko-toothed Species or species habitat
Whale, Gingko Beaked Whale [59564] may occur within area

Mesoplodon grayi
Gray's Beaked Whale, Scamperdown Whale [75] Species or species habitat
may occur within area

Orcaella brevirostris
Irrawaddy Dolphin [45] Species or species habitat
known to occur within area

Orcinus orca
Killer Whale, Orca [46] Species or species habitat
may occur within area

Peponocephala electra
Melon-headed Whale [47] Species or species habitat
may occur within area

Physeter macrocephalus
Sperm Whale [59] Species or species habitat
may occur within area

Pseudorca crassidens
False Killer Whale [48] Species or species habitat
likely to occur within area

Sousa chinensis
Indo-Pacific Humpback Dolphin [50] Breeding known to occur
within area
Stenella attenuata
Spotted Dolphin, Pantropical Spotted Dolphin [51] Species or species habitat
may occur within area

Stenella coeruleoalba
Striped Dolphin, Euphrosyne Dolphin [52] Species or species habitat
may occur within area

Stenella longirostris
Long-snouted Spinner Dolphin [29] Species or species habitat
may occur within area

Steno bredanensis
Rough-toothed Dolphin [30] Species or species habitat
may occur within area

Tursiops aduncus
Indian Ocean Bottlenose Dolphin, Spotted Bottlenose Species or species habitat
Dolphin [68418] likely to occur within area

Tursiops aduncus (Arafura/Timor Sea populations)

Spotted Bottlenose Dolphin (Arafura/Timor Sea Species or species habitat
populations) [78900] known to occur within area

Tursiops truncatus s. str.

Bottlenose Dolphin [68417] Species or species habitat
may occur within area

Ziphius cavirostris
Cuvier's Beaked Whale, Goose-beaked Whale [56] Species or species habitat
may occur within area

Commonwealth ReservesTerrestrial [ Resource Information ]

Name State Type
Christmas Island EXT National Park (Commonwealth)

Australian Marine Parks [ Resource Information ]

Name Label
Name Label
Abrolhos Habitat Protection Zone (IUCN IV)
Abrolhos Multiple Use Zone (IUCN VI)
Abrolhos National Park Zone (IUCN II)
Abrolhos Special Purpose Zone (IUCN VI)
Argo-Rowley Terrace Multiple Use Zone (IUCN VI)
Argo-Rowley Terrace National Park Zone (IUCN II)
Argo-Rowley Terrace Special Purpose Zone (Trawl) (IUCN VI)
Ashmore Reef Recreational Use Zone (IUCN IV)
Ashmore Reef Sanctuary Zone (IUCN Ia)
Cartier Island Sanctuary Zone (IUCN Ia)
Dampier Habitat Protection Zone (IUCN IV)
Dampier Multiple Use Zone (IUCN VI)
Dampier National Park Zone (IUCN II)
Eighty Mile Beach Multiple Use Zone (IUCN VI)
Gascoyne Habitat Protection Zone (IUCN IV)
Gascoyne Multiple Use Zone (IUCN VI)
Gascoyne National Park Zone (IUCN II)
Joseph Bonaparte Gulf Multiple Use Zone (IUCN VI)
Joseph Bonaparte Gulf Special Purpose Zone (IUCN VI)
Kimberley Habitat Protection Zone (IUCN IV)
Kimberley Multiple Use Zone (IUCN VI)
Kimberley National Park Zone (IUCN II)
Mermaid Reef National Park Zone (IUCN II)
Montebello Multiple Use Zone (IUCN VI)
Ningaloo National Park Zone (IUCN II)
Ningaloo Recreational Use Zone (IUCN IV)
Oceanic Shoals Habitat Protection Zone (IUCN IV)
Oceanic Shoals Multiple Use Zone (IUCN VI)
Oceanic Shoals Special Purpose Zone (Trawl) (IUCN VI)
Roebuck Multiple Use Zone (IUCN VI)
Shark Bay Multiple Use Zone (IUCN VI)

Extra Information
State and Territory Reserves [ Resource Information ]
Name State
Adele Island WA
Airlie Island WA
Bardi Jawi WA
Barrow Island WA
Bedout Island WA
Bernier And Dorre Islands WA
Bessieres Island WA
Boodie, Double Middle Islands WA
Broome Bird Observatory WA
Broome Wildlife Centre WA
Browse Island WA
Bundegi Coastal Park WA
Cape Range WA
Coulomb Point WA
Dambimangari WA
Dirk Hartog Island WA
Jurabi Coastal Park WA
Karajarri WA
Lacepede Islands WA
Lesueur Island WA
Locker Island WA
Low Rocks WA
Lowendal Islands WA
Mitchell River WA
Montebello Islands WA
Muiron Islands WA
Murujuga WA
North Turtle Island WA
Nyangumarta Warrarn WA
Prince Regent WA
Name State
Round Island WA
Serrurier Island WA
Swan Island WA
Tanner Island WA
Unnamed WA26400 WA
Unnamed WA28968 WA
Unnamed WA36907 WA
Unnamed WA36909 WA
Unnamed WA36910 WA
Unnamed WA36913 WA
Unnamed WA36915 WA
Unnamed WA37168 WA
Unnamed WA37338 WA
Unnamed WA40322 WA
Unnamed WA40828 WA
Unnamed WA40877 WA
Unnamed WA41080 WA
Unnamed WA41775 WA
Unnamed WA44665 WA
Unnamed WA44669 WA
Unnamed WA44672 WA
Unnamed WA44673 WA
Unnamed WA44674 WA
Unnamed WA44677 WA
Unnamed WA51105 WA
Unnamed WA51162 WA
Unnamed WA51497 WA
Unnamed WA51583 WA
Unnamed WA51617 WA
Unnamed WA51932 WA
Unnamed WA52354 WA
Uunguu WA
Wilinggin WA

Invasive Species [ Resource Information ]

Weeds reported here are the 20 species of national significance (WoNS), along with other introduced plants
that are considered by the States and Territories to pose a particularly significant threat to biodiversity. The
following feral animals are reported: Goat, Red Fox, Cat, Rabbit, Pig, Water Buffalo and Cane Toad. Maps from
Landscape Health Project, National Land and Water Resouces Audit, 2001.

Name Status Type of Presence

Birds
Anas platyrhynchos
Mallard [974] Species or species habitat
likely to occur within area

Columba livia
Rock Pigeon, Rock Dove, Domestic Pigeon [803] Species or species habitat
likely to occur within area

Gallus gallus
Red Junglefowl, Domestic Fowl [917] Species or species habitat
likely to occur within area

Lonchura oryzivora
Java Sparrow [59586] Species or species habitat
likely to occur within area

Meleagris gallopavo
Wild Turkey [64380] Species or species habitat
likely to occur within area

Passer domesticus
House Sparrow [405] Species or species habitat
likely to occur within area
Name Status Type of Presence
Passer montanus
Eurasian Tree Sparrow [406] Species or species habitat
likely to occur within area

Streptopelia senegalensis
Laughing Turtle-dove, Laughing Dove [781] Species or species habitat
likely to occur within area

Sturnus vulgaris
Common Starling [389] Species or species habitat
likely to occur within area

Frogs
Rhinella marina
Cane Toad [83218] Species or species habitat
likely to occur within area

Mammals
Bos taurus
Domestic Cattle [16] Species or species habitat
likely to occur within area

Camelus dromedarius
Dromedary, Camel [7] Species or species habitat
likely to occur within area

Canis lupus familiaris

Domestic Dog [82654] Species or species habitat
likely to occur within area

Capra hircus
Goat [2] Species or species habitat
likely to occur within area

Equus asinus
Donkey, Ass [4] Species or species habitat
likely to occur within area

Equus caballus
Horse [5] Species or species habitat
likely to occur within area

Felis catus
Cat, House Cat, Domestic Cat [19] Species or species habitat
likely to occur within area

Mus musculus
House Mouse [120] Species or species habitat
likely to occur within area

Oryctolagus cuniculus
Rabbit, European Rabbit [128] Species or species habitat
likely to occur within area

Rattus exulans
Pacific Rat, Polynesian Rat [79] Species or species habitat
likely to occur within area

Rattus rattus
Black Rat, Ship Rat [84] Species or species habitat
likely to occur within area

Sus scrofa
Pig [6] Species or species habitat
likely to occur within area

Vulpes vulpes
Red Fox, Fox [18] Species or species habitat
likely to occur within area

Plants
Andropogon gayanus
Gamba Grass [66895] Species or species
Name Status Type of Presence
habitat likely to occur within
area
Cenchrus ciliaris
Buffel-grass, Black Buffel-grass [20213] Species or species habitat
likely to occur within area

Cryptostegia grandiflora
Rubber Vine, Rubbervine, India Rubber Vine, India Species or species habitat
Rubbervine, Palay Rubbervine, Purple Allamanda likely to occur within area
[18913]
Cylindropuntia spp.
Prickly Pears [85131] Species or species habitat
likely to occur within area

Dolichandra unguis-cati
Cat's Claw Vine, Yellow Trumpet Vine, Cat's Claw Species or species habitat
Creeper, Funnel Creeper [85119] likely to occur within area

Eichhornia crassipes
Water Hyacinth, Water Orchid, Nile Lily [13466] Species or species habitat
likely to occur within area

Jatropha gossypifolia
Cotton-leaved Physic-Nut, Bellyache Bush, Cotton-leaf Species or species habitat
Physic Nut, Cotton-leaf Jatropha, Black Physic Nut likely to occur within area
[7507]
Lantana camara
Lantana, Common Lantana, Kamara Lantana, Large- Species or species habitat
leaf Lantana, Pink Flowered Lantana, Red Flowered may occur within area
Lantana, Red-Flowered Sage, White Sage, Wild Sage
[10892]
Opuntia spp.
Prickly Pears [82753] Species or species habitat
likely to occur within area

Parkinsonia aculeata
Parkinsonia, Jerusalem Thorn, Jelly Bean Tree, Horse Species or species habitat
Bean [12301] likely to occur within area

Prosopis spp.
Mesquite, Algaroba [68407] Species or species habitat
likely to occur within area

Reptiles
Hemidactylus frenatus
Asian House Gecko [1708] Species or species habitat
likely to occur within area

Lycodon aulicus
Wolf Snake, Common Wolf Snake, Asian Wolf Snake Species or species habitat
[83178] likely to occur within area

Lygosoma bowringii
Christmas Island Grass-skink [1312] Species or species habitat
likely to occur within area

Ramphotyphlops braminus
Flowerpot Blind Snake, Brahminy Blind Snake, Cacing Species or species habitat
Besi [1258] known to occur within area

Nationally Important Wetlands [ Resource Information ]

Name State
"The Dales", Christmas Island EXT
Ashmore Reef EXT
Big Springs WA
Bunda-Bunda Mound Springs WA
Cape Range Subterranean Waterways WA
De Grey River WA
Eighty Mile Beach System WA
Hosine's Spring, Christmas Island EXT
Mermaid Reef EXT
Name State
Mitchell River System WA
Prince Regent River System WA
Roebuck Bay WA
Shark Bay East WA
Willie Creek Wetlands WA
Yampi Sound Training Area WA

Key Ecological Features (Marine) [ Resource Information ]

Key Ecological Features are the parts of the marine ecosystem that are considered to be important for the
biodiversity or ecosystem functioning and integrity of the Commonwealth Marine Area.

Name Region
Carbonate bank and terrace system of the Van North
Pinnacles of the Bonaparte Basin North
Shelf break and slope of the Arafura Shelf North
Ancient coastline at 125 m depth contour North-west
Ashmore Reef and Cartier Island and surrounding North-west
Canyons linking the Argo Abyssal Plain with the North-west
Canyons linking the Cuvier Abyssal Plain and the North-west
Carbonate bank and terrace system of the Sahul North-west
Commonwealth waters adjacent to Ningaloo Reef North-west
Continental Slope Demersal Fish Communities North-west
Exmouth Plateau North-west
Glomar Shoals North-west
Mermaid Reef and Commonwealth waters North-west
Pinnacles of the Bonaparte Basin North-west
Seringapatam Reef and Commonwealth waters in North-west
Wallaby Saddle North-west
Ancient coastline at 90-120m depth South-west
Perth Canyon and adjacent shelf break, and other South-west
Western demersal slope and associated fish South-west
Western rock lobster South-west
Caveat
The information presented in this report has been provided by a range of data sources as acknowledged at the end of the report.

This report is designed to assist in identifying the locations of places which may be relevant in determining obligations under the Environment
Protection and Biodiversity Conservation Act 1999. It holds mapped locations of World and National Heritage properties, Wetlands of International
and National Importance, Commonwealth and State/Territory reserves, listed threatened, migratory and marine species and listed threatened
ecological communities. Mapping of Commonwealth land is not complete at this stage. Maps have been collated from a range of sources at various
resolutions.

Not all species listed under the EPBC Act have been mapped (see below) and therefore a report is a general guide only. Where available data
supports mapping, the type of presence that can be determined from the data is indicated in general terms. People using this information in making
a referral may need to consider the qualifications below and may need to seek and consider other information sources.

For threatened ecological communities where the distribution is well known, maps are derived from recovery plans, State vegetation maps, remote
sensing imagery and other sources. Where threatened ecological community distributions are less well known, existing vegetation maps and point
location data are used to produce indicative distribution maps.

Threatened, migratory and marine species distributions have been derived through a variety of methods. Where distributions are well known and if
time permits, maps are derived using either thematic spatial data (i.e. vegetation, soils, geology, elevation, aspect, terrain, etc) together with point
locations and described habitat; or environmental modelling (MAXENT or BIOCLIM habitat modelling) using point locations and environmental data
layers.

Where very little information is available for species or large number of maps are required in a short time-frame, maps are derived either from 0.04
or 0.02 decimal degree cells; by an automated process using polygon capture techniques (static two kilometre grid cells, alpha-hull and convex hull);
or captured manually or by using topographic features (national park boundaries, islands, etc). In the early stages of the distribution mapping
process (1999-early 2000s) distributions were defined by degree blocks, 100K or 250K map sheets to rapidly create distribution maps. More reliable
distribution mapping methods are used to update these distributions as time permits.

Only selected species covered by the following provisions of the EPBC Act have been mapped:
- migratory and
- marine
The following species and ecological communities have not been mapped and do not appear in reports produced from this database:

- threatened species listed as extinct or considered as vagrants

- some species and ecological communities that have only recently been listed
- some terrestrial species that overfly the Commonwealth marine area
- migratory species that are very widespread, vagrant, or only occur in small numbers
The following groups have been mapped, but may not cover the complete distribution of the species:
- non-threatened seabirds which have only been mapped for recorded breeding sites
- seals which have only been mapped for breeding sites near the Australian continent
Such breeding sites may be important for the protection of the Commonwealth Marine environment.

Coordinates
-14.26314 100.97127,-9.8201 101.10456,-9.10922 102.59298,-8.28726 103.63709,-8.0651 105.36988,-8.10953 107.14709,-8.08732 109.39083,-
8.08732 110.36829,-8.3539 111.19026,-8.22061 112.03443,-8.30947 113.3007,-8.48719 114.43367,-8.55384 115.41114,-7.95403 115.85544,-
8.3539 116.01095,-8.66491 116.32196,-8.82042 116.8107,-8.7982 118.05475,-8.70934 118.76563,-8.15396 119.20994,-8.02067 120.00968,-
8.3539 120.27627,-8.66491 121.4981,-8.62048 122.58664,-8.3539 123.27531,-8.10953 125.18582,-8.04289 126.80753,-8.02067 128.02936,-
8.04289 128.87354,-8.88707 129.27341,-9.62017 129.62886,-9.86453 130.18424,-10.37548 129.80658,-10.64206 129.27341,-11.55289
129.18455,-12.06384 129.29563,-12.46371 129.56221,-13.99656 129.09569,-13.88548 128.42924,-13.86327 127.11854,-14.70744 125.58569,-
15.3739 125.31911,-15.57384 124.87481,-16.3958 124.76373,-16.66238 124.16392,-17.16723 124.11563,-17.79535 123.56411,-17.35105
123.36418,-16.79567 122.76437,-17.10668 122.34228,-18.46181 122.52,-18.75061 121.9424,-19.75029 121.27595,-20.12795 118.78785,-
20.48339 117.92146,-20.59447 116.94399,-20.83883 115.58886,-21.59415 115.18899,-21.99402 113.745,-23.19364 113.4562,-24.882
113.03412,-27.0813 113.25627,-27.83662 113.3007,-27.70333 113.07855,-28.23649 112.7231,-28.12541 111.39019,-27.68111 111.32355,-
27.74776 112.58981,-27.03687 112.83418,-26.32598 112.45652,-26.48149 111.23469,-25.70396 110.54602,-25.99276 110.14614,-25.81503
109.72405,-25.08193 110.41272,-24.90421 111.41241,-24.10447 112.16772,-23.08257 111.56791,-22.14953 111.34576,-21.48307 111.47905,-
20.90548 111.2569,-19.97244 111.34576,-19.52814 111.23469,-19.26156 111.8345,-18.95054 112.10108,-18.17301 112.10108,-17.92864
111.03475,-18.21744 110.70152,-18.72839 109.70184,-18.37295 109.03538,-17.23997 108.72437,-17.30662 108.48,-16.32915 107.52475,-
16.61795 106.88051,-16.64016 105.56981,-17.08447 105.05886,-16.64016 104.85893,-15.61827 105.36988,-15.95149 104.61456,-15.84042
104.03697,-16.21808 103.215,-16.01814 102.59298,-15.92928 101.85988,-14.97403 101.23785,-14.26314 100.97127
Acknowledgements
This database has been compiled from a range of data sources. The department acknowledges the following
custodians who have contributed valuable data and advice:
-Office of Environment and Heritage, New South Wales
-Department of Environment and Primary Industries, Victoria
-Department of Primary Industries, Parks, Water and Environment, Tasmania
-Department of Environment, Water and Natural Resources, South Australia
-Department of Land and Resource Management, Northern Territory
-Department of Environmental and Heritage Protection, Queensland
-Department of Parks and Wildlife, Western Australia
-Environment and Planning Directorate, ACT
-Birdlife Australia
-Australian Bird and Bat Banding Scheme
-Australian National Wildlife Collection
-Natural history museums of Australia
-Museum Victoria
-Australian Museum
-South Australian Museum
-Queensland Museum
-Online Zoological Collections of Australian Museums
-Queensland Herbarium
-National Herbarium of NSW
-Royal Botanic Gardens and National Herbarium of Victoria
-Tasmanian Herbarium
-State Herbarium of South Australia
-Northern Territory Herbarium
-Western Australian Herbarium
-Australian National Herbarium, Canberra
-University of New England
-Ocean Biogeographic Information System
-Australian Government, Department of Defence
Forestry Corporation, NSW
-Geoscience Australia
-CSIRO
-Australian Tropical Herbarium, Cairns
-eBird Australia
-Australian Government – Australian Antarctic Data Centre
-Museum and Art Gallery of the Northern Territory
-Australian Government National Environmental Science Program
-Australian Institute of Marine Science
-Reef Life Survey Australia
-American Museum of Natural History
-Queen Victoria Museum and Art Gallery, Inveresk, Tasmania
-Tasmanian Museum and Art Gallery, Hobart, Tasmania
-Other groups and individuals

The Department is extremely grateful to the many organisations and individuals who provided expert advice
and information on numerous draft distributions.

Please feel free to provide feedback via the Contact Us page.

© Commonwealth of Australia
Department of the Environment
GPO Box 787
Canberra ACT 2601 Australia
+61 2 6274 1111
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Document No: 2000-010-G000-GE00-G00000-HE-5880-00002 Unrestricted Page 593

“Copy No 01” is always electronic: all printed copies of “Copy No 01” are to be considered uncontrolled.
 Shell Australia Pty Ltd Revision 12

Prelude Environment Plan 05/01/2021

Document No: 2000-010-G000-GE00-G00000-HE-5880-00002 Unrestricted Page 594

“Copy No 01” is always electronic: all printed copies of “Copy No 01” are to be considered uncontrolled.
 Shell Australia Pty Ltd Revision 12

Prelude Environment Plan 05/01/2021

Document No: 2000-010-G000-GE00-G00000-HE-5880-00002 Unrestricted Page 595

“Copy No 01” is always electronic: all printed copies of “Copy No 01” are to be considered uncontrolled.