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Jimucrrt, 15, 2008 pilge I <br />1.0 INTRODUCTION <br />This report is the culmination ofa year-long characterization effort and analyses. It has <br />been organized to present results of recent laboratory testing of core from the landslide area and <br />results of the core logging. This data has been used to characterize the rock mass. An <br />assessment of the spoils stability is presented to identify the maximum spoil pile heights. <br />Observations and recommendations are presented as they apply to future mining of reserves <br />within the G-Pit and K-Pit area. <br />The objective ofthis work has not been to reanalyze the stability of the landslide. One of <br />the conclusions from this study, in fact, is that reanalysis is not necessary because no substantial <br />changes have been identified since the original analysis of the landslide. Given uncertainties in <br />rock strength variations and groundwater variations across the site, reanalysis is not necessarily <br />expected to be more accurate. This report is not intended to serve as the mine design for the <br />G-Pit and K-Pit area of the mine. Trapper Mining, Inc. (TMI) will consider results from these <br />efforts and recommendations to develop a detailed mine design. <br />1.1 Background <br />A large landslide occurred in the G-Pit and K-Nit area of the Trapper Mine over the <br />weekend of October 8. 2006. A site visit was conducted and a report was issued by Agapito <br />Associates, Inc. (AAI) documenting geotechnical and mining conditions immediately after the <br />landslide.] Additionally, a geotechnical scope of work was developed to examine causes and <br />assess likelihood ofsimilar events occurring in the future. The scope included (])calibration of <br />a slope stability model to conditions existing at the time of landslide failure. (2) assess risks to <br />other mining areas. (3) characterize post-landslide condition of rock mass in landslide, <br />(4) provide technical support for regulatory issues, (5) assess implications to remaining reserves, <br />(6) and evaluate the Icasibility of future mine plans from geotechnical perspective. <br />Preliminary model analysis ofG-Pit andL-Dip Pit stability were presented to TMI in an <br />interim report which addressed Colorado Division of Reclamation, Mines, and Safety (DRMS) <br />preliminarily questions about the landslides The modeling analysis details for the G-Pit <br />landslide analyses were documented in a stand-aline report." This report presented our <br />understanding ofthe causes of the landslide given information existing at the time on the most <br />likely conditions and failure mechanisms. Results confirmed that the untimely combination of <br />( I ) saturation from heavy recent rains, (2) a weaker than expected mudstone seam just above the <br />L-seam, and (3) insufficient buttress material in the old G-Strike Pit most likely lead to the <br />landslide initiation. <br />Agapito Associates, Inc. (2006), "Trip Report on G-Pit Landslide of October 8, 2006." prepared for Trapper <br />Mining, Inc., November 30. <br />Agapito Associates, Inc. (2006), "Scope of Work and Budget Estimate for Investigation of G-Pit Landslide and <br />Impacts to Future Mining." prepared for Trapper Mining, inc., October 24. <br />Agapito Associates, Inc. (2007), "Interim Report of G-Pit and L.-Pit Stability Analyses-Task 4," prepared for <br />'Trapper `lining. Inc.. February 7. <br />Agapito Associates, Inc. (2007), "G-Pit Landslide Stability Report Task 2," prepared for Trapper Mining, Inc.. <br />March 9. <br />Agapito Associates, Inc.