2011-10-12_INSPECTION - M1980244

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OBSERVATIONS PERMIT #: M- 1980 -244 INSPECTOR'S INITIALS: BMK INSPECTION DATE: September 21, 2011 1) The Division conducted a monitoring and construction progress inspection of the site on 9/21/11. Present during the inspection were Tim Comer of CC &V and Joe Hickey of Amec the design engineer's representative, conducting the QA /QC for the construction portion of the operation. 2) The Phase V leach pad construction area was inspected. Along the upper portion of the south facing slopes north of the pregnant pond, clay, geomembarne and drain cover were being deployed at different portion of the pad. The deployed liner was walked and inspected and found to be in good repair. According to Joe Hickey Ames construction plans to complete as much if not all the liner deployment before the end of this construction season. While in the area Kim Morrison of AMEC, the design engineer for Phase 6 ( AM 10) met us in the area to discuss the yearly slope stability inspection that CC &V is required to conduct on the existing leach facility. The Division requested for her evaluation to include impacts of the hydro jex process on the overall slope stability of the pad. She agreed to include that in her slope stability evaluation of the pad. 3) The inspection continued to the existing valley heap leach pads I thru V. The pads were actively being leached at the time of the inspection. The phase IVC pad inter phase ditch area was inspected and found to be in good repair. CC &V is going to submit a TR to extend the berm along this area. While inspecting the pad, the following readings were collected from the pregnant ponds high and low solution collection pressure transducers. 4) Phase I high volume solution collection transducer # 1 was recorded at 25.0 # 2 was at 41.0 and # 3 was at 41.6. The low volume solution collection transducer # 1 was at 0.34 and # 2 was at 0.41. The piezometers for the pond was at 44.5 for # 1 and 31.5 for # 2. The phase II high volume solution collection transducer # 4 was recorded at 13.0 # 5 was at 14.0 and # 6 was at 13.9. The low volume solution collection transducer # 1 was recorded at 0.50 and # 2 was at 0.71. The phase IV High volume solution collection transducer # 7 was recorded at 12.4 # 8 was at 11.0 # 9 was at 10.4 and # 10( pipe) was at 9.7.The low volume solution collection transducer # 1 recorded at 12.6 and # 2 was at 12.7 inches of hydro static head. The phase V high volume solution collection transducer # 311 was recorded at 12.94 # 312 was at 13.09 # 313 was at 13.02 and # 314 was at 12.94. The low volume solution collection transducer # 1 was recorded at 12.3 and # 2 was at 13.1 inches of hydrostatic head.( All other pressure transducer readings are in feet of hydrostatic head) 5) The external pond was inspected. It was holding about the same amount of water as observed during the last inspection. The low volume solution collection transducer for the pond were at 9.7 for # 1 and 15.6 for # 2. The under drain discharge area was inspected. Both the south and 4 inch pipes were discharging. All the water from these ponds is pumped back to the heap leach as make up water All the lower ponds were dry with the exception of the large lower pond which was holding a very small amount of water. After the inspection discussed the next sampling time in Areqau and under drain. CC &V is going to drill a deeper aquifer well after samples are collected. The deep well will have the same numeric protection levels as the upper aquifer well CRMW -3B, which is a compliance well. The sulfate standards set by the Division for this well had exceeded the numeric protection levels twice in 2011. The Division has been working with the operator on the appropriate remedial action such as pumping back the 1.5 gpm total yield to the pump back station as make up water. Page 2 of 4