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May 28, 2009 <br />1.0 INTRODUCTION AND BACKGROUND <br />Page I <br />The K-Pit at Trapper Mine will be mined using a truck-and-shovel mining operation. In <br />October 2006, there was a landslide event in the entire K-Pit and adjacent G-Pit area (on the <br />east). The failure surface was rooted along the L Seam floor mudstone. The sliding block came <br />to rest against the spoil pile of G-Strike Pit.I Mining operation in K-Pit will require the <br />construction of a toe buttress. The reason for construction of this structure is rooted in the safety <br />of the operation, as this buttress will serve to stabilize the area against further movement down <br />slope. <br />Prior to construction of the buttress, the area to be filled will be properly prepared. <br />Topsoil will be salvaged wherever practical. The area underlying the toe of the fill will be <br />broken up to eliminate the potential for development of a slip plane. Using spoil generated <br />during mining of the K-Pit, the buttress will be constructed in lifts up from the existing <br />topography. Lifts will not exceed 100 vertical feet, and will typically be 25 to 50 vertical feet. <br />According to construction plans laid out by Trapper Mining, Inc. (TMI), these lifts will be placed <br />from the exterior of the buttress structure towards the center. A suitable berm will be <br />constructed at dump points, allowing end dumps to back up to the edge of the fill, and dump. As <br />conditions require, (more likely with increased lift height), trucks may dump short of the berm, <br />and use of a dozer to push the material to the lift edge may be required. Overall, the construction <br />plans may be modified, as required by field conditions. <br />The slopes of the fill structure are planned at a maximum of 3H: IV. They will also be <br />contoured to blend with existing topography. While lifts are being placed, each lift will be <br />constructed in such a manner that drainage is facilitated, and surface water accumulation is <br />avoided. This in turn will reduce the amount of infiltration into the buttress fill structure. The <br />K-Pit buttress will be left as a permanent feature. This should continue to prevent additional <br />movement in the landslide area. Following the construction of the buttress, topsoil will be <br />brought back to cover the fill, which will be permanently vegetated, in accordance with the <br />permit accorded to Trapper Mining, Inc. (TMI). <br />2.0 SLOPE STABILITY ANALYSIS <br />' The landslide-affected area in K-Pit will be mined using the truck-and-shovel method of <br />mining. The mining plan in the K-Pit area calls for the spoils to be placed in three separate <br />areas: (1) downdip of the K-Pit (as a toe buttress), (2) in Horse Gulch, and (3) in previously <br />mined K-Pit cuts. Within the K-Pit, mining will progress up to the R Seam and the spoils will be <br />set on the R Seam floor. A simplified stability analysis of the backfill spoil and downdip toe <br />buttress was performed to assess their stability after reclamation and this report was submitted to <br />' TMI.2 Based on results obtained during this analysis and operational changes, a new <br />configuration for the K-Pit toe buttress was developed by TMI. The revised toe buttress <br />configuration was given to Agapito Associates, Inc. :(AAI), to investigate the long-term global <br />' stability of the buttress structure. <br />1 Agapito Associates, Inc. (2007), "G-Pit Landslide Stability Report-Task 2" prepared for Trapper <br />Mining, Inc., March 19. <br />z Agapito Associates, Inc. (2008), "Simplified K-Pit with Toe Buttress Stability Analysis Report" <br />prepared for Trapper Mining, Inc., July 28. <br />Agapito Associates, Inc.