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S Memo to Berhan Keffelew CRESSON Leak Collection Audit page 2 discussion of the leak collection, leak detection and piezometer monitoring facilities. We also discussed CC&VG's monitoring frequencies, analytical sampling requirements, and reporting procedures. We first inspected the area of the saturated pool immediately adjacent to the toe dam. Ore was first placed to allow access to the foundation area for the three pump cans. Three 20' thick lifts of ore have been placed, bringing a portion of the sump area to approximately 10' below the toe dam crest. The pumps have been placed in the pump cans and the pregnant solution circulation system has been largely installed. Two approximately 100' x 300' grids of solution dripper piping have been installed above the ore. Solution has been transported from Ponds 5 and SA and placed on the ore. Sodium Cyanide has been added temporarily to the solution at the site of the ore. Next I inspected the five leak detection sumps. Sump No. 1, the most northern of the sumps, had accumulated approximately 1 milliliter of fluid. The sump No. 1 collection area is completely above the area currently exposed to processing solution. Frost was evident on the walls of the sump and the exposed length of pipe. I suspect the small amount of fluid is the result of melting frost, rather than in inflow from the leak detection pipe. The other four leak detection sumps evidenced some frost but had accumulated no fluid in their collection sumps. No leakage has been detected to date. As of the February 17, 1995 inspection by Berhan Keffelew and Mike Long, none of these conditions had changed. Leak Collection System Performance The composite liner design approved for the CRESSON Mine Heap Leach Pad saturated pool area provides for the collection of leaking processing fluids in a leak collection granular filter layer beneath the primary geomembrane liner. Within the saturated pool area of the pad, the leak collection filter material is underlain by a composite geomembrane liner and clay layer. Outside the saturated pool area, the remainder of the pad is underlain by the composite liner.t C &VG is r o maintain the head on the c site liner below 2.0 feet. Head is monitored outsi e the saturate poo ive vibrating wire piezometers placed immediately above the geomembrane liner. Head is monitored within the leak collection filter layer by pressure transducers installed in immediate proximity to the redundant pumps which withdraw fluid from the 30' x 100' collection sump. The fluids pumped from the sump are monitored by a flow meter to determine the volume of fluid pumped. In accordance with the permit fluids pumped from the leak collection system are returned to the processing circuit. CC&VG is