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Cripple Creek & Victor Gold Mining Company Squaw Gulch Valley Leach Facility Design <br />• 925 feet long; <br />• Minimum crest width of 87 feet; <br />• 2.5H:1 V upstream slope; and <br />• 2H:1V downstream slope. <br />During construction of the PSSA embankment, a temporary tunnel and haul road will <br />be constructed over State Highway 67, as illustrated in Drawings A900 through A920. <br />This traffic separation will provide uninterrupted access to build the embankment. The <br />earthen embankment will be constructed using structural fill compacted to 95 percent <br />of the standard Proctor maximum dry density at or near the optimum moisture content. <br />Once construction of the embankment is complete, the highway will be constructed <br />across the embankment, meeting the standards the Colorado Department of <br />Transportation (CDOT). <br />4.5 Valley Leach Facility (VLF) Foundation <br />Preparation of the VLF foundation includes clearing and grubbing, placing compacted <br />structural fill during site grading, and placing SLF. The Phase I and II VLF site grading <br />plans are presented on Drawings A205 and A210. The site - grading plan was <br />developed to provide a stable VLF foundation while promoting internal drainage to the <br />PSSA. The VLF grading plan has been designed so that leach solution applied within <br />the lined area will flow into the ore and be collected by an internal HVSCS. <br />Growth media removed from the footprint of the VLF area will be stockpiled in an area <br />designated by CC &V for use during future reclamation activities. <br />The site - grading plan was developed based on the April 2010 topographic survey <br />information from Foresight West. In general, areas of the VLF where the natural grade <br />is in excess of 2.5H:1 V will be flattened to 2.5H:1 V by excavating or by compacting <br />structural fill in controlled horizontal lifts prior to SLF placement. However, there are <br />some areas within the VLF footprint that have been designed at a steeper slope up to <br />2H:1 V due to site constraints. These areas have been limited to locations within the <br />VLF where the steeper slopes will not affect stability of the facility. The final site <br />grading contours may vary from those shown on the foundation grading plan drawing <br />to suit natural conditions encountered during construction. Variations from the <br />designed grading plan will be evaluated to assess impact to the VLF performance and <br />stability. Typical cross sections for the VLF are shown on Drawing A150. <br />As discussed in Section 2.4 and presented in Appendix D, historic underground <br />workings are located within the limits of the VLF. These workings will need to be <br />remediated as part of the foundation preparation. The remediation details for the <br />underground workings are presented in Drawing A270. <br />Project No: 74201125G0 Page 19 <br />1 September 2011 <br />amec° <br />