2012-02-28_REVISION - M1980244 (85)

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During the onsite audit, the only ponding observed on the heaps was at the lime infiltration basins that CC &V constructed on top of the Phase IV leach area. Slaked lime is placed in the basins and allowed to infiltrate into the heap to enhance alkalinity. The temporary basins are constructed on the heap bench just ahead of the next lift of ore material that is being placed on the VLF. Once the lime in the basins is allowed to infiltrate into the heap, the basins are covered by the progressing ore lift. CC &V indicated that during the time the basins are exposed, there is constant activity (e.g., trucks dumping) in the area of the advancing dump face, which serves to deter wildlife. Additionally, the solution typically infiltrates quickly and/or forms a slurry composition. Therefore, CC &V has not implemented any temporary protective measures in the past. Nonetheless, CC &V updated its Wildlife Protection Plan to include additional exclusionary measures to deter wildlife from standing process solution in active areas of the leaching and process facilities. The lime infiltration basins observed during the audit have since been covered with ore. CC &V first implemented operation of the lime infiltration basins in the second quarter of 2009, during the period between ICMC audits. During this onsite recertification audit, the CC &V Leach Pad Supervisor indicated that measures (such as ripping with a dozer) have been implemented as necessary to promote infiltration and rectify any ponding that has occurred in the lime infiltration basins over this period. Therefore, in the auditor's professional judgment, the ponding observed during this audit was an isolated incident, which was quickly remedied. Furthermore, the operation demonstrated that measures are taken to prevent reoccurring ponding and updated its Wildlife Protection Plan to implement additional protective measures, if they become necessary in the future. These factors form the basis for the finding of full compliance under this Standard of Practice. The audit field inspection combined with the results of the wildlife mortality monitoring demonstrate that the CC &V procedures for applying leach solutions, inspecting the leach areas, and remediating ponding issues are being effectively implemented to minimize ponding and protect wildlife. 4.5 Implement measures to protect fish and wildlife from direct and indirect discharges of cyanide process solutions to surface water. The operation is: • in full compliance ❑ in substantial compliance ❑ not in compliance...with Standard of Practice 4.5. Discuss the basis for the Finding/Deficiencies Identified: The regulatory standard for cyanide in surface water (0.02 mg /1 WAD cyanide) applicable to the Cresson Project is based on calculated flows in Cripple Creek and "reasonable potential analysis." The Arequa Gulch "use protective status" is Cold Water Cresson Project Name of Mine September 22, 2010 Signature of Lead Auditor Date Page 15 of 36