JORC TECHNICAL REPORT

OF PT. Sinar Peridotindo

7.2 Topographic Survey

In April year 2014, PT. SEAL engaged national geodetic contractor,

PT. Stalaktit Indonesia (PTSI) to perform a fully package ground topography
survey to cover 550 ha of Tumbang Hangai coal property. The work consisted
of obtaining bench mark networking and original digital terrain model (DTM).
Firstly, three pairs of local bench marks (BM) and eight series of pegging
were established on the tenement area by occupying three geodetic global
position system (GPS) instruments, Trimble 5700.

Using the Universal Transverse Mercator (UTM) 49 south coordinate

system under WGS 1984 spheroid, the local bench mark networking is measured
or linked to the N1.2047 National Geospatial Informatics Biro (BIG) reference
point, situated on Katingan Hilir district office. The BM survey complied
with Indonesia National Standard (SNI) 19-6724-2002.

Table 7.1: National Geospatial Informatics Reference Point coordinate list

GEOGRAPHIC UTM
NO
LATITUTE LONGITUTE ELEVATION EASTING NORTHING ELEVATION
N1.2047 1° 54' 45,39" 113° 23' 10,38" 60.91 765,456.42 9,788,413.80 17.30

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JORC TECHNICAL REPORT
OF PT. Sinar Peridotindo

Once these BMs were established, they were reduced to a mean-sea-level

elevation datum or geoid plan Earth Gravitational Model 2008 (EGM), which was
determined by a continuous 6-hour survey followed by level traverse between all
control stations.

The raw field data was processed by using Spectra Precision Survey Office
(SPCO) software. The final data processing came out with relative ellipse error of
within 95% level of confidence and summarized as below;

Table 7.2: BM Measurement Accuracy

Summary

Adjusted Grid
Coordinates

Point Easting Easting Error Northing Northing Error Elevation Elevation Error
ID (Meter) (Meter) (Meter) (Meter) (Meter) (Meter) Fixed

BM1 703489.674 0.036 9850974.212 0.030 53.035 0.144

BM2 702744.453 0.037 9849432.033 0.030 75.507 0.144
BM3 702441.803 0.037 9852239.897 0.031 50.815 0.146
N1_2 765456.426 ? 9788413.800 ? 17.304 ? ENe

Adjusted Geodetic Coordinates

Height Height Error

Point ID Latitude Longitude Fixed
(Meter) (Meter)
BM1 S1°20'51.32167" E112°49'44.04165" 96.586 0.144
BM2 S1°21'41.54329" E112°49'19.97525" 118.996 0.144
BM3 S1°20'10.14461" E112°49'10.11814" 94.390 0.146
N1_2 S1°54'45.39498" E113°23'10.38310" 60.914 ? ENe

Error Ellipse
Components

Semi-major axis Semi-minor axis

Point ID Azimuth
(Meter) (Meter)
B M1 0.049 0.032 121°
B M2 0.049 0.032 120°
B M3 0.050 0.033 121°

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 JORC TECHNICAL REPORT
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Distance Semi-major Semi-minor

No. Station a (mm) r (mm) Remaks
(km) axis (m) axis (m)
1 BM-01 88,055 0,049 0,032 58,523 88,255 a < r
2 BM-02 87,499 0,049 0,032 58,523 87,699 a < r
3 BM-03 89,692 0,050 0,033 59,908 89,892 a < r

Table 7.3: Local bench mark coordinate list

BENCH COORDINATE
NO MARK LONGITUTE LATITUTE EASTING NORTHING ELEVATION
1 BM-01 703489,674 9850974,212 53,035
2 BM-01A 703491,147 9851032,397 52,829
3 BM-01B 1° 20' 52,78713" 112° 49 ' 44,03083" 703489,306 9850929,195 52,619
4 BM-02 1° 21' 41,54329" 112° 49 ' 19,97525" 702744,453 9849432,033 75,507
5 BM-02A 1° 21' 40,24940" 112° 49 ' 17,19129" 702658,412 9849471,844 81,810
6 BM-02B 1° 21' 42,24491" 112° 49 ' 16,06598" 702623,575 9849410,571 74,318
7 BM-03 1° 20' 10,14461" 112° 49 ' 10,11814" 702441,803 9852239,897 50,815
8 BM-03A 1° 20' 10,30902" 112° 49' 11,33303" 702479,360 9852234,818 50,372

The scope of work also included point of observation survey, drill collar
pick up and drill site setting out by using electronic total station devices. A
range of topographic data was collected from various sources and of variable
quality. The survey was based on WGS 84 spheroid datum and Egm 2008 geoid
datum.

Ground survey data containing 4,205 points of observation were measured in

40 m to 50 m ray spacing within 12.544 km in length polygon. Polygon points
are linked to bench mark networking. A total of 93 drill collars were picked up by
ground survey. About 11 drill collars have low confidence level in
elevation accuracy compared to ground DTM. Local surveying was carried out
using electronic Total Station equipment in closed polygon scheme. All survey
works were carried out by professional in-house engineers. All outcrop
locations and drill hole collars were ground surveyed.

PT. SUMBER ENERGI ALAM September 3

JORC TECHNICAL REPORT
OF PT. Sinar Peridotindo

A range of topographic data was collected at properties from various

sources and of variable quality. The highest quality data was the ground survey
data described below:

 Block 550 ha has two datum points, 15 loops and 5,168 surveyed points
of observation,
 The ground survey work generated DTM with 1 meter contour interval
and maximum errors survey of approximately 0.3 m/km for horizontal
value and
0.02 m/km for vertical value.

PT SI generated DTM by using Spectra Precision survey office soft

program and produced a 1 meter contour interval of topography map. The DTM
has measured horizontal and vertical root mean square (RMSx-y-z), as shown in
table below;

Table 7.4 Horizontal and vertical root mean square loops closure summary

Poligon Lenght Point of Linier

observa Angle error fx (m) fy (m) fh (m)
Traverse (m) Accuracy
tions
South – East 3.776,32 48 – 00º 00’ 21” 0,152 0,032 0,020 1 : 24.242
South – West 6.517,82 68 00º 01’ 20” 0,305 0,223 –0,010 1 : 17.258
West 2.249,93 22 00º 00’ 36” 0,120 0,099 0,004 1 : 14.495

With regard to the devices being used and accuracy of quality control of the
data processing, the ground topography result is classified as high confidence
data.

PT. SUMBER ENERGI ALAM September 3