2009-09-21_PERMIT FILE - C1981010 ‎(13)‎

• Permit No: C1981010
• IBM Index Class Name: Permit File
• Doc Date: 9/21/2009
• Doc Name: Trapper G-Pit Landslide Mining Assesment, January 2008
• Section_Exhibit Name: Appendix T
• Media Type: D
• Archive: No

January 15, 2008
LIST OF TABLES
Page ii
Page
Table 1. Summary of Laboratory Testing Results ...................................................................8
Table 2. Mechanical Properties Used in the ZD-02 Spoil Calibration FLAC31) Model .........24
Table 3. Results from Spoil Strength Calibration Cases ........................................................26
Table 4. Mechanical Properties Used in the G-Pit Spoil Stability FLAC Model ....................28
Table 5. Summary of Results for Cases Analyzed .................................................................30
Table 6. Estimate Recoverable Reserves from Landslide Area ..............................................53
LIST OF FIGURES
Page
Figure 1. Aerial Photograph with Location of Initial Characterization Boreholes and
Outlines of Landslide Extent and Massive Slide Block ............................................. ..4
Figure 2. Post-Landslide Topographic with Location of Initial Characterization Boreholes,
Phase 11 Boreholes, and Water Monitoring Holes .................................................... ..5
Figure 3. Projection of Previous Characterization Boreholes 05-G1-CCR through
05-G5-CCR to Approximate Location in Landslide ................................................. ..7
Figure 4. Stress-Strain Curve for Q-Floor Mudstone Sample from 07-GI7-CCR from 227 ft
Below Collar ........................................................................................................... ..9
Figure 5. Lithology for Borehole 07-GI 1-CCR ...................................................................... 12
Figure 6. Lithology for Borehole 07-GI2-CCR ...................................................................... 13
Figure 7. Lithology for Borehole 07-G13-CCR ...................................................................... 14
Figure 8. Lithology for Borehole 07-GI4-CCR ...................................................................... 15
Figure 9. Lithology for Borehole 07-G15-CCR ...................................................................... 16
Figure 10. Lithology for Borehole 07-G16-CCR ...................................................................... 17
Figure 11. Lithology for Borehole 07-G17-CCR ...................................................................... 18
Figure 12. Lithology for Borehole 07-GX5-CCR ..................................................................... 19
Figure 13. Lithology for Borehole 07-GX6-CCR ..................................................................... 20
Figure 14. Surveyed Section ofZ-Dip Cut #2 Pit Spoil Failure Showing Pre-Slide and
Post-Slide Profile .................................................................................................... 24
Figure 15. Conceptual 3D Model of Z-Dip Cut #2 Pit Spoil Pile .............................................. 25
Figure 16. Unstable Velocity Contours and Large Displacement Vectors for Cases where
Spoil Strength is at the Limit of Equilibrium from Model of Z-Dip Cut #2 Pit
Spoil Pile ................................................................................................................ 26
Figure 17. FLAC Model Cross Section Simulation of G-Pit Spoil Pile with a Slope of 37.6°
Illustrating Material Groups and Groundwater Table ............................................... 29
Figure 18. Contours of Velocity at Equilibrium for 1.3H:1 V Slope Angle and 68-ft-high
Pile Under Saturated Residual Strength Condition for Q-Floor Mudstone Bedding
Dipping at 13° ......................................................................................................... 31
Figure 19. Contours of Velocity at Equilibrium for 1.3H:1 V Slope Angle and 30-ft-high
Pile Under Saturated Residual Strength Condition for Q-Floor Mudstone Bedding
Dipping at 25° ......................................................................................................... 32
Figure 20. Elevation Contours of Q-Seam Floor in Feet Above MSL in the K-Pit Area of
the Mine ................................................................................................................. 34
Figure 21. Slope Contours of the Q-Seam Floor in Degrees in the K-Pit Area .......................... 35
Figure 22. Highwall Stability Failure at G-Test Pit in 2001 ...................................................... 36
Figure 23. Highwall Slope Stability Failure at G-Strike Pit After August 2004 Failure ............ 37
Agapito Associates, Inc.