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Cripple Creek & Victor Gold Mining Company Squaw Gulch Valley Leach Facility Design <br />overlain by three (3) feet of low volume solution collection fill (LVSCF), overlain by a <br />100 -mil smooth LLDPE geomembrane, overlain by two (2) feet of DCF. <br />The VLF ore stacking design was generally developed using 1.6H:1V overall side <br />slopes around the perimeter of the VLF, with the exception of the area upgradient of <br />the PSSA toe berm (2.5H:1V) and above the mill platform (2.0H:1 V). The maximum <br />ore depth over the liner is limited to 800 feet as determined by laboratory testing of the <br />liner material (contained in Appendices B.2 and B.6). However, based on topographic <br />constraints, the maximum ore depth as demonstrated by the proposed ultimate ore <br />configuration (Figure 1) is approximately 700 feet, as reported herein. <br />Native ground recontouring and grading within the limits of the VLF were developed so <br />that the foundation slopes would be 2.5H:1V or shallower, with the exception of <br />localized areas with slopes of 2H:1 V, as discussed in Section 4.5. The VLF ultimate <br />ore topography is shown on Drawing A100, and cross sections through the VLF are <br />shown on Drawing A150. <br />The pregnant solution generated during operation of the VLF will be contained within <br />the VLF internal PSSA. The PSSA will be constructed within the lower section of the <br />VLF on native ground and compacted fill. The PSSA is formed by the natural valley <br />side slopes and terminated by the PSSA containment embankment, or toe berm. This <br />embankment also forms part of the Highway 67 realignment. The proposed PSSA <br />embankment and a portion of the Highway 67 realignment are illustrated in Drawing <br />A207. <br />The majority of the OSA will be constructed on native ground and compacted fill. <br />Along the eastern edge, the OSA will be constructed along the regraded slopes of the <br />existing Squaw Gulch Overburden Storage Area (SGOSA) and the proposed mill <br />platform. Drawings A200 through A202 illustrate the proposed grading in the vicinity of <br />the future mill platform. <br />As part of the VLF design, a water balance was conducted to evaluate the volume of <br />solution that will be generated as a result of the operation of the proposed VLF. The <br />water balance model accounts for the following components: (i) normal operating <br />volume; (ii) solution accumulation due to seasonal climatic variations to a 95 percent <br />confidence interval; (iii) 12 -hour draindown during pump outages; (iv) excess water <br />during extreme climatic conditions (100 - year /24 -hour storm event); and (v) available <br />pore space of the ore within the PSSA. Additional capacity is maintained within the <br />PSSA to accommodate the minimum freeboard of 5 feet, as measured from lowest <br />point on the crest of the PSSA. <br />Operational and post closure surface water diversion systems have been designed <br />around the perimeter of the VLF. The operational diversion channel will be constructed <br />along the margins of the VLF, as illustrated in Drawings A500 and A510 for Phases 1 <br />and 2 of the VLF, respectively. During construction and operation of the VLF, <br />temporary surface water diversion channels will be constructed to route surface water <br />Project No.: 74201125G0 Page 3 <br />1 September 2011 <br />amec° <br />