2012-02-28_REVISION - M1980244 (85)

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The facilities for mixing, unloading, and storage of cyanide have not changed since the June 2007 certification audit. They are located within the security perimeter of the mine, physically distant (2 -5 miles) from any dwellings or communities. CC &V employs a cyanide producer- designed dissolution system [i.e., the CyPlus® SLS (Solid -to- Liquid System)]. The SLS system is connected to the supplier's stainless steel ISO delivery tanks, water and caustic soda introduced, and the solution cycled between a stationary mixing tank and the delivery tank until all solid cyanide is dissolved. The final solution is then transferred to CC &V's solution storage tank. The mixing and storage tanks are both fitted with audible high -level alarms, and tank levels are monitored remotely by process operators in the ADR Plant control room. During the SLS process the cyanide delivery tanks are staged on a concreted pad sloped to a sump within the containment for the stationary mixing and storage tanks. The cyanide storage and mixing tanks are both located within a dedicated concrete impoundment; the impoundment and the entire adjacent ADR building are also underlain by an HDPE barrier that is sloped to drain to the VLF. At the time of this onsite recertification audit, there was not a written procedure for pumping out the offload sump, although CC &V stated that operators are properly trained. CC &V was requested to create a new SOP to address the procedure for pumping out the offload sump. Following the onsite audit, CC &V updated the appropriate inspection checklist provide guidance for identifying when pumping of the offload sump at the cyanide Offload and Storage Facility is required. CC &V also updated the affected SOPs to demonstrate that inspection and cleaning of the sump area are documented, and to provide appropriate standards and guidance for pumping out the sump. With respect to the secondary containment providing a competent barrier to leakage, a number of cracks and areas of spalling were noted within the impoundment. CC &V staff members were requested to initiate appropriate repairs, to adjust associated inspection guidelines to include appropriate visual standards for initiating maintenance or repair, and to conduct appropriate training in the requirements of the revised inspection/maintenance standards. All requested actions were completed prior to submittal of this SAR. The storage area is within the security perimeter of the mine, and there is no public access. However, during the observation of a solution mixing /offloading event, contractor maintenance actions were underway that included forklift traffic on the roadway immediately adjacent to the delivery tank apron. CC &V staff members were requested to modify cyanide mixing and offload procedures to require temporary barriers to block the roadway and thereby restrict access to the apron to authorized personnel only while mixing/offload activities were underway. Requested actions were completed prior to submittal of this SAR. No incompatible materials were being stored with cyanide solution except for a potential situation identified in the ADR Plant where an acid wash vessel used in the carbon Cresson Project Name of Mine September 22, 2010 Signature of Lead Auditor Date Page 7 of 36