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January 15, 2008 Page 2 <br />Stability of hillside slopes in the Z-Dip Pit and A-Pit areas have been examined to assess <br />the potential for similar large-scale landslide events occurring elsewhere at the mine. The report <br />on the Z-Dip Pit stability5 had assumed rock properties and hydrologic conditions similar to <br />G-Pit stability analysis. This stability analysis was necessary because the Z-Dip Pit mining with <br />G-Test Pit downdip creates geometry similar to that of G-Dip Pit prior to the landslide. Results <br />predict that the hillside in Z-Dip Pit area has a high safety factor against sliding. The East-Panel <br />dip pit mining has similar hillside geometry with A-Pit downdip of mining. A stability analysis <br />of the East-Panel hillside was performed and documented in a report. Results from this analysis <br />predicted that the East-Panel hillside above A-Pit is expected to remain stable assuming similar <br />conditions thought to have triggered the G-Pit landslide. <br />The remaining geotechnical activities outlined in the scope document2 have been <br />completed. This report presents the results of the characterization efforts (including borehole <br />logging, lab testing, and spoils stability analysis) and addresses the geotechnical implications of <br />ground conditions on future mining and recoverable reserves. <br />1.2 Objectives <br />The overall objective for characterizing the landslide area is to demonstrate an <br />understanding of existing ground conditions so that a compatible mining strategy can be <br />developed to safely extract coal reserves in and below the landslide. Specific objectives include <br />the following: <br />Locate and characterize the shear zone(s) or slip plane(s) of the landslide. <br />Characterize the rock material within landslide block, and estimate the disturbance as it <br />influences coal recovery and excavation stability. <br />• Characterize lithology below the slide plane as it influences coal recovery and highwall <br />stability. <br />Quantify post-landslide rock strength properties and assess how differences might impact <br />conclusions from previous stability analyses. <br />Provide an indication of potential reserve recovery from seams within and below <br />landslide. <br />Provide recommendations for spoil pile heights on steep bedding of K-Pit area. <br />Provide an assessment of highwall stability in truck and shovel and dragline mining <br />areas. <br />1.3 Characterization Program <br />A two-phase characterization drilling program was developed. The first phase was <br />implemented in late fall 2006 soon after the landslide occurred. It was temporarily stopped prior <br />5 Agapito Associates, Inc. (2007), "Z-Dip Pit Stability Report Task 5," prepared for Trapper Mining, Inc., <br />March 19. <br />6 Agapito Associates, Inc. (2007), "Numerical Analysis of Highwall Mining Viability in East A Pit Considering <br />Landslide Potential," prepared for Trapper Mining, Inc., July 16. <br />Agapito Associates, Inc.