2012-02-28_REVISION - M1980244 (85)

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6.2 Operate and monitor cyanide facilities to protect worker health and safety and periodically evaluate the effectiveness of health and safety measures. The operation is: • in full compliance ❑ in substantial compliance ❑ not in compliance...with Standard of Practice 6.2. Describe the basis for the Finding/Deficiencies Identified: SOPs on Emergency Response, Cyanide Spillage, and HCN Gas stress the importance of maintaining cyanide solutions above pH 10 and to closely monitor pH when levels fall below this. The pH of the cyanide solutions in the ADR Plant are maintained by application of caustic during the batch mixing process, and pre- treatment batch mixing process. In addition lime is added to the leach pads to maintain the alkalinity of the leach solution. The pH of barren and pregnant solutions is monitored through collection and analysis of grab samples. In addition to the sampling program, there are inline pH- meters located at each of the carbon trains that provide backup data if required. The cyanide related SOPs specify when personal gas- monitoring units must be used for specific operations and when operators or maintenance personnel work in areas where there is a potential for HCN exposure Toxipro personal HCN detectors used. The monitors are calibrated to alarm at 4.7 ppm and 10 ppm. Fixed HCN SensAlert monitoring systems are located in ten areas of the ADR Plant where there is a potential for generation of HCN gas. The systems are each equipped with visual and audible alarms that trigger at 4.7 ppm and 10 ppm. SensAlert readouts boxes are located in the control room where HCN levels may be monitored by process operators. At the time of the audit the readouts ranged for 0.0 to 0.4 ppm. The HCN monitors are maintained and calibrated as recommended by the manufacturer and maintenance records are retained. Documented procedures are also in place and signage present throughout the ADR Plant and VLF that alert workers to hazards and specify the PPE requirements when performing activities where there may be a potential for exposure to cyanide. Workers have been trained in these procedures, as well as emergency response in the event of a cyanide release. Placement of warning signage was observed to be generally good. Cyanide warning signs are posted at frequent intervals around the VLF, on the doors of the ADR building and on piping and vessels inside and outside the ADR Plant. Piping containing cyanide was also well marked to show flow direction. With few exceptions, signage was observed to be clean, clear and posted in visible places. Exceptions were noted on overhead piping in the areas of the ADR Plant, where grime made signage illegible. Subsequent to this onsite recertification audit, CC &V modified the inspection procedure Cresson Project Name of Mine September 22, 2010 Signature of Lead Auditor Date Page 25 of 36