ENVIRONMENTAL
IMPACT ASSESSMENT
- E I A -
Prof. S.Chieng
Ci vil Engineering
UBC
Suggested references
B. F. Noble (2006). Introduction to Environmental
Impact Assessment. Oxford University Press.
K.S. Hanna (2005) Environmental Impact Assessment:
practice and participation. Oxford University Press.
Wood, C. (2002). Environmental Impact Assessment:
a Comparative Review (2
nd
Edition). Harlow, Prentice
Hall.
What is E I A ?
An important procedure for ensuring that
the likely effects of new development on the
environment are fully understood and
taken into account before the development
is allowed to go ahead.
The International
The International Association for Impact
Assessment (lAIA) defines ElA as:
The process of identifying, predicting, evaluating and
mitigating the biophysical, social, and other relevant
effects of development proposals prior to major
decisions being taken and commitments made.
What is it really ?
Environmental Impact Assessment is an
activity (or a tool) which identifies, predicts,
interprets and communicates information,
and proposes ameliorative measures, about
impacts of a proposed action or
development proposal on human health
and the well-being of the ecosystem upon
which human survival depends.
environmentally sound and sustainable design
better compliance with standards
savings in capital and operating costs
reduced time and costs for approvals
increased project acceptance
better protection of the environment and
human health
Benefits of EIA include :
Generalized
E I A Process
Flowchart
Engineering/Economic/Social Planning
Project + Mitigation
Environmental Planning
Engineering/Economics/Social Planning
Environmental Impact Assessment
Project + Mitigation
Sequential
Parallel
Engineering/Economic/Social Planning/Environment Project
Integrated
Engineering/Economic/Social Planning
Project + Mitigation
Environmental Planning
Parallel
Screening
Is an EIA needed?
Many projects may have no significant
environmental effects
A screening mechanism seeks to
identify those projects with potentially
significant adverse environmental
effects
Scoping
The scope of an EIA is the issues and
impacts it addresses
Scoping is the process of deciding which of
a projects possible alternatives and impacts
should be addressed in the EIA
Scoping is carried out in discussions
between the developer, the competent
authority, relevant agencies and, ideally, the
public
Baseline studies
Following the scoping phase, it is essential
to assemble all the relevant information on
the current status of the environment
The baseline study should anticipate the
future state of the environment assuming
the project is not undertaken - the no
action alternative
This provides the baseline against which
future impacts can be assessed
Predictions
How any project component may give
rise to an impact
Probability of impacts occurring
Magnitude of each impact
Spatial and temporal of each impact
Impact assessment
(Evaluation)
Impact assessment involves evaluating the
significance of the impacts identified
Significance can be determined through
professional judgement, reference to
regulations etc.
Potential for bias in determining what is
significant
The conclusions of the impact assessment
can ultimately be used by decision-makers
when determining the fate of the project
application
Mitigation
Negative impacts on the environment
identified during the EIA can be alleviated
through mitigation measures
The mitigation hierarchy: Avoid - Reduce
- Remedy - Compensate - Enhance
Impacts remaining after mitigation are
known as residual impacts
In EIA, an Environmental Impact Statement
should include details on
any adverse environmental effects which
cannot be avoided should the proposal be
implemented
alternatives to the proposed action
Environmental Impact Statement (EIS)
EIS preparation / review
EIS is a formal document which includes
information on the development and
information relating to screening, scoping,
baseline studies, predictions, etc.
EIS preparation / review
Once complete, the EIS is submitted
to the competent authority (along with
the planning application)
The EIS is often reviewed (either
formally or informally)
The review enables the competent
authority to decide whether the EIA is
adequate, accurate and unbiased
The EIS should include the following information, although not
necessarily in this order:
Executive summary;
Statement of project objectives;
Identification and description of project alternatives;
Rationale for selection of the preferred option;
Detailed project description of the preferred option;
Description of the existing environment;
Description and evaluation of the predicted impacts;
Identification of, and commitment to mitigation and enhancement
measures and appropriate post-Environmental Impact Assessment (EIA)
studies (Compliance Schedule); and
Documentation of the public participation program.
Sec. 1502.10 (US NEPA) Recommended format of EIS.
Agencies shall use a format for environmental impact statements which will
encourage good analysis and clear presentation of the alternatives including the
proposed action. The following standard format for environmental impact
statements should be followed unless the agency determines that there is a
compelling reason to do otherwise:
(a) Cover sheet.
(b) Summary.
(c) Table of contents.
(d) Purpose of and need for action.
(e) Alternatives, including proposed action
(f) Affected environment.
(g) Environmental consequences
(h) List of preparers.
(i) List of Agencies, Organizations, etc. to which EIS copies are sent.
(j) Index.
(k) Appendices (if any), including supporting data
(a) Cover sheet
title of proposed action
list of responsible agencies
contact person at agencies
designation of EIS as draft, final or supplement
date by which comments must be received
(b) Summary
major conclusions
areas of controversy
issues to be resolved
(c) Table of contents.
(d) Purpose of and need for action.
(e) Alternatives, including proposed action
(f) Affected environment.
(g) Environmental consequences
environmental impacts of alternatives, including proposed action
adverse environ. effects which cannot be avoided if proposal is implemented
mitigation measures to be used & residual effects of mitigation
relation between short-term uses of the environ. & maintenance &
enhancement of long-term productivity
irreversible or irretrievable commitments of resources if proposal is
implemented, discussion of :
- direct and indirect effects and their significance
- possible conflicts between actions and objectives of land use
plans, policies, controls....etc.
- natural resource requirements and conservation strategy
- effects on historic and cultural resources, built environment, and
quality of life
- means to mitigate adverse impacts
(h) List of preparers.
(i) List of Agencies, Organizations, etc. to which EIS copies are sent.
(j) Index.
(k) Appendices (if any), including supporting data
Public consultation
EIA requires that, as much as possible, both
technical (scientific) and philosophical (value)
issues be dealt with.
public consultation is an integral part of EIA
different view points are brought forward, concerns
aroused are identified, potential conflict areas are
pinpoints, and the comfort level of decision makers
is raised.
Monitoring
Monitoring should determine:
the accuracy of the original predictions
the degree of deviation from the
predictions
the possible reasons for any deviations
the extent to which mitigation measures
have achieved their objectives
EIA tools
1. Ah hoc methods
these are perhaps the oldest and crudest
approaches to EIA. These methods focus
on broad areas of possible impacts rather
than specifying specific parameters to be
investigated. There are often based on
objectivity and intuition.
2. Checklists
Checklists are a variant of the Ah Hoc
method. A prescribed list of parameters is
considered in the assessment process. While
the list of environmental parameters are
investigated for possible impacts, the explicit
establishment of direct cause-effect links to
the project activities are not required.
EIA tools contd
Sample checklist - for a bridge construction project
Proposed project acti vities Yes No
dredging
blasting
pier construction
traffic diversion
Affected physical components
water quantity
water quality
soil quality
soil stability
air quality
Affected biological components
fish populations
spawning habitat
bird habitat
wildlife habitat
Affected socio-economic components
employment
noise
health
3. Matrices
Two-dimensional tables used to identify
impacts arising from the interaction between
project activities and specific environmental
components.
Leopold matrix
Peterson matrix
Component interaction matrix
etc
EIA tools contd
Ex. Leopold matrix
-9 3 -8 2 B
-8 2 A
e d c b a
1
2
8
1
7
5
Project actions
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Example of a section of the Leopold Matrix
Sample of an
Impact
Assessment
Matrix
Sample of an Three-Dimensional Impact Matrix
EIA tools contd
4. Map overlay
A series of maps (transparencies) is used to
identify, predict, assign relative significance
to, and communicate impacts of the project.
It is geographically reference. GIS system is
normally used these days.
EIA tools contd
5. The Battelle environmental evaluation
system
Designed by Battelle Columbus Laboratories,
USA to assess the impacts of water resource
developments, water quality management plans,
highways, nuclear power plants and other
projects. The system is essentially a very
sophisticated checklist.
Sample : Checklist for Huasai-Thale Noi Road Project, Thailand
Note:
Provide detailed explanation
on each of the check in
the Checklist.
