2008-04-15_REVISION - M1980244 (309)

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Solution from the pregnant solution distribution tank is currently routed to the carbon trains at the ADR to extract gold and then into the barren solution tank for recycling back to the VLF for application. As part of the MLE Project, the solution enrichment circuit will be upgraded at the ADR. This allows for an option to circulate pregnant solution from Phases I, II and IV PSSAs onto Phase 5 VLF effecting enrichment of the gold in solution. As part of the enrichment circuit upgrade, pregnant solution from the Phases I, II and IV PSSAs can either be pumped to the pregnant solution distribution tank and into the carbon trains at the ADR or can be pumped to the enrichment tank for routing to the Phase 5 VLF. The enrichment tank is an existing tank located adjacent to the barren solution tark and within the existing ADR containment system. The enrichment tank has a capacity of 100,000 gallons. The pregnant solutions will be pumped from the enrichment tank to the Phase 5 VLF using four 800 horsepower pumps that will be identical to the current barren solution pumps. Fresh water will be added to the enrichment tank as necessary to maintain a flow of approximately 14,500 gpm to Phase 5 VLF. It should be noted that while it is expected that the majority of the leaching at Phase 5 VLF will utilize pregnant solution from Phases I, II, III and IV, the exact make up of fresh water and pregnant solution may vary in accordance with pregnant solution concentrations, economic considerations, and flow distributions indicated by the dynamic water balance model for the VLF. Once the solutions applied on the Phase 5 VLF reach the Phase 5 PSSA, the solution will be pumped to the pregnant solution distribution tank at a rate of approximately 14,000 gpm using three 250 horsepower pumps. The remaining approximately 750 gpm from the application rate will be consumed in the ore material as the ore reaches field capacity or lost as evaporation from the system. There is an additional pump online to serve as a backup to keep solution circulating in the event that one of the primary pumps goes down for any reason. At the pregnant solution distribution tank, the flows are routed to the existing ADR carbon trains for gold extraction and then recirculated to Phases I - IV via the barren pumps. Should line power go down for any reason, there will be backup generators that will provide power to keep the pumping operational. Three backup generators currently are in place adjacent to the ADR and provide the necessary power at the ADR in the event of power failuire to line power supply system. An additional three backup generators will be • Cripple Creek & Victor Gold Mining Company Cresson Project Mine Life Extension 7-4