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Cripple Creek & Victor Gold Mining Company Squaw Gulch Valley Leach Facility Design <br />EXECUTIVE SUMMARY <br />The Cripple Creek & Victor Gold Mining Company (CC &V) operates the Cresson Project located <br />west of the city of Victor in Teller County, Colorado. Phase I and Phase II of the Cresson <br />Project Valley Leach Facility (VLF) were designed in 1993 and constructed in phases during <br />1994 through 1996. In July 1998, CC &V submitted a design for Phase III of the VLF. <br />Construction on Phase III began in 1999 and was completed in 2000. In March 2000, CC &V <br />submitted a design for Phase IV. The construction on Phase IV began in 2001 and was <br />completed in 2004. In August 2008, CC &V submitted a design for Phase 5 of the VLF, which is <br />currently under construction. CC &V is proposing a new VLF located in the Squaw Gulch, north <br />of the current Cresson Project VLF. The Squaw Gulch VLF design includes the following <br />elements: <br />• Relocation of a portion of Highway 67 in Squaw Gulch to accommodate the new <br />VLF; <br />• Construction of a toe berm across Squaw Gulch to stabilize the VLF and provide <br />the foundation for the new Highway 67 alignment; <br />• Installation of a temporary multi -plate tunnel on Highway 67 to provide access for <br />construction equipment during installation of the toe berm; <br />• Construction of a new VLF with a footprint area encompassing Squaw /Anaconda <br />and Swede Gulches; <br />• Construction of an earthen platform adjacent to the VLF to accommodate <br />relocation of the mill; and <br />• Installation of a dedicated Pregnant Solution Storage Area (PSSA) for the VLF. <br />The Squaw Gulch VLF area will consist of an additional +/- 15 million square feet (surface area <br />corrected for slope) of geomembrane -lined area in the Ore Storage Area (OSA) and new <br />Pregnant Solution Storage Area (PSSA). These structures will include the use of composite <br />liner systems, similar to those approved and used for the Cresson Project VLF. <br />Surface grading within the limits of the Squaw Gulch VLF will be conducted in a manner which <br />results in foundation slopes that are generally 2.5H:1 V (horizontal:vertical) or shallower, with the <br />exception of localized areas within the OSA where slopes of up to 2.0H:1 V will be constructed. <br />Though the current stacking plan reflects an ore height of only 700 feet, the design has been <br />developed based on loading associated with stacking ore to a maximum height of 800 feet <br />above the lined surface using an in -place ore dry density of 110 pounds per cubic foot (pcf). <br />The Squaw Gulch VLF final ore topography is shown on Figure 1. Cross sections through the <br />Squaw Gulch VLF are shown on Figure 2. <br />The water balance for sizing of the Squaw Gulch VLF PSSA includes the following components: <br />(i) operating volume; (ii) draindown volume; (iii) solution accumulation due to seasonal climatic <br />variation at a 95- percent confidence level; (iv) 100 - year /24 -hour design storm event; and (v) <br />available pore space of the ore within the PSSA. <br />Project No.: 74201125G0 <br />1 September 2011 <br />amec's' <br />