2010-12-17_REVISION - C1981019 ‎(130)‎

• Permit No: C1981019
• IBM Index Class Name: Revision
• Doc Date: 12/17/2010
• Doc Name: Exhibit 6 Item 7 Geology Pre-Feasibility Part 2
• Type & Sequence: PR3
• Media Type: D
• Archive: No

• mineralogy is also predictable where these properties are known. However, in the rase of the
Colowyo data reflected here, the relationship is not as sound as expected, which may reflect;
- Genuine variation between seams due to differences in ash type (possible) or rank
(unlikely).
Inter - laboratory variability and/or inconsistency in the handling and storage of coal
samples.
A disconnect between the moisture and ASG analyses, giving rise to errors in the
conversion to dry basis.
Variability induced by the ASG test procedure, which is based on lump coal at ambient
conditions.
•
Further investigation is required to ensure the integrity of the base data for tonnage and coal
quality estimation. TS recommends these apparent anomalies be investigated and resolved
with the laboratory's input.
Once corrected, this relationship can be used to calculate theoretical dry basis tonnages in
the current geological model and mining schedules, as an intermediate step in the reserve
calculation process. To calculate in situ coal tonnages, the dry density is adjusted to in situ
(bed) moisture by applying the accepted change of basis formula. The average estimated
densities of Collom coal at various bases are presented in Table 2 -2.
Reporting Basis Average Average Ash Average
Moisture I %) N Relative Density
In situ (as analysed)
14.4
15.1
1.47
Air dried (calculated)
6.0
16.2
1.52
Dry basis (calculated)
0
17.1
1.66
Table 2 -2:
Relative Density Reported at
Varying Moisture Bases
The in situ relative density
is estimated to average
1.47, which
is higher than the figure
currently used by CCC.
2.3.4 Coal Quality - Specific Energy
Significant differences in specific energy have been observed at CCC between different
exploration and analytical program groups. There is normally a strong relationship between
ash and energy on a dry basis.
Results from the Utah International, early KEC drilling programmes and the Mine Area drilling
show good apparent internal consistency (R' values of 0.983, 0.998 and 0.986 respectively),
• but show some scatter. The Mine Area drilling shows a slightly higher energy content than
the others. The Grace drilling and the Mine Area Quality Control drilling do not show such
1110
T1NTn
Ts Ref: DRAFT Version: 1 9 1n1 11--