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Exhibit D CMLRB 112 Permit Application <br />Agile Stone Systems. Inc. <br />• zones where the mining benches, originally left at 50' vertical height and 50' deep <br />benches at the end of mining, will be drilled and shot back to 25' depth of bench and the <br />rock talus left at slopes no greater than l:l. The rubble-ized zones will grade into area of <br />revegetated mining bench, as described in more detail in the Reclamation Exhibit E. A <br />cross section drawing of the proposed highwall configuration is included in this <br />application. <br />The configuration was analyzed for safety factor utilizing a BHP Engineering GALENA <br />SLOPE STABILITY ANALYSIS SYSTEM Version 2.Oa. Assumptions in the program <br />input included 0.15 Earthquake Loading Factor, reflecting the earthquake/seismic history <br />for this part of central Colorado from the Seismicity Map of The State of Colorado, <br />USGS Map MF-2036. Most granite mining will take place above 5,780' elevation <br />beginning in Phase I. Subsequent mining to the southeast will drop lower to maintain a <br />visual barrier and to correspond to the storm water retention berm built along the <br />southern boundary of the mined area. All mining will be above the expected water table <br />for this azea. No water was identified in exploratory pits and drilling in the granite water <br />at these levels. Phreatic surface and piezomtric water pressure factors aze not expected to <br />impact the highwall safety analysis. (Azurite, Inc. 10/97) <br />Factor of Safety results aze estimated to be a minimum of 2.5 and above, with many of <br />the failure projections resulting in 4.0 or greater. Due to the high degree of competency <br />of this crystalline rock, it is reasonable to assume that the highwall configuration plan as <br />• proposed will result in a long term stable rock face which will no[ create a hazard to <br />wildlife or the general public. (Azurite, Inc., 10/97) <br />• <br />[7 <br />