2008-04-15_REVISION - M1980244 (329)

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• the VLF and external storage pond) is typically dry, indicating that there is no indirect discharge to surface water from the VLF. The VLF is operated as a zero- discharge facility, and review of engineering reports and operating records indicates that this operating target has been met throughout the life of the CC&V operation. The key objectives of the model are to maintain an optimum water balance which maximizes gold extraction, minimizes water use, avoids discharge situations, optimizes cyanide use, and maintains sufficient volumes in the internal/external pumping systems so the pumps do not cavitate. The model is reviewed daily by the Metallurgical Group and twice a week in an inter-group meeting involving Metallurgical, Process Operations, and Environmental Resources staff. Meeting summary notes are kept; action items are established with assignments and schedules. SOPs have been established for the continuous optimization of the water balance; procedures require routine precipitation measurement, recording, and input to the probabilistic model and related control strategies. SOPs define methods for actively moving water between the six major operating areas of the VLF to maintain in-heap "freeboard", which is monitored on an hourly basis. At any point in time, the operator has instantaneous data available for the area under leach and associated flows. Four primary phases are further broken down into six areas and a number of sub-units. Makeup or excess volumes are recorded to enable cross-system solution transfers and modifications to application rates, or new ore additions. Downgradient monitoring provisions include low level and high volume indicators; the Leak Detection, Collection, and Recovery System (LDCRS); a transducer network; and several other redundant cross-checks. Routine monitoring and maintenance inspections are also performed daily by the Metallurgical, Process Operations and Environmental Resources Group personnel. The water balance considers the following inputs/criteria: • Solutions are applied to six major areas on the VLF; these six areas are further subdivided and individually monitored. Cresson Project Name of Mine ~--~' Signature of Lead Auditor 10 September 2007 Date Page 14 of 41