2012-02-28_REVISION - M1980244 (77)

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IS mi DTH 1. GENERAL FACILITY DESCRIPTION 1.1.The Squaw Gulch High Grade Mill Facilities (High Grade Mill) are being developed to allow enhanced gold recovery of various higher grade ore deposits that exist at the Cripple Creek & Victor Gold Mining Company's (CC &V) Cresson Project. The mined higher grade ore will be crushed in the existing CC &V primary and secondary crushing facilities. The crushed higher grade ore will be further reduced in size in the High Grade Mill to allow efficient capture of gold by flotation processes and in -tank leaching processes described below. The processed ore will then be agglomerated and placed on either the existing Arequa Gulch Valley Leach Facility (AGVLF) or proposed new Squaw Gulch Valley Leach Facility (SGVLF) where additional gold recovery will occur. The entire mill facilities will be constructed upon the liner system associated with the SGVLF. 2. PROCESS DESCRIPTION Design Summary Squaw Gulch High Grade Mill Facilities 2.1. Stockpile and Feed Systems - Higher grade ore stockpile and reclaim area 2.2.Grinding and Gravity Systems - Comminution Circuit 1/24/2012 Page 1 of 6 After the higher grade ore is crushed to approximately 3/4" in the existing crushing facilities, it is transferred by mine haul trucks from the existing Load Out Bin to the High Grade stockpile area. Three High Grade stockpiles will allow higher grade ore of differing rock type and grade to be segregated. A reclaim stockpile will be created by blending the differing ores from the three stockpiles with a front end loader. The high grade ore from the reclaim stockpile will be recovered with the Ore Apron Feeder, which will be located in the reclaim tunnel under the reclaim stockpile, which will feed the Rod Mill Feed Conveyor at a rate of approximately 250 tons per hour to transfer the high grade ore to the grinding circuit (comminution circuit) which will further reduce the particle size to approximately 1,000 microns in diameter. From the reclaim system, the high grade ore will be transferred to the grinding system. The reclaim system will be equipped with dust control devices or systems to minimize potential dust emissions during this process. The grinding system will consist of a single rod mill operating in conjunction with a ball mill at a rate of approximately 250 tons per hour of sized product at a circulating load of 250 %. Coarse ore reclaimed from the stockpile will be fed into the rod mill feed chute via the Rod Mill Feed Conveyor. Makeup water at an anticipated rate of 466 gallons per minute will be added to the new ore as it enters the rod mill. The rod mill will reduce the particle size of the ore from approximately %" dia. to approximately 1,000 microns in diameter. The rod mill discharge will flow by gravity through a trommel screen.