2011-09-12_INSPECTION - M1980244

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OBSERVATIONS PERMIT #: M -1980 -244 INSPECTOR'S INITIALS: BMK INSPECTION DATE: August 17, 2011 1) The Division conducted a monthly monitoring and construction progress inspection of the site on 7/17/11. The main purpose of the inspection in addition to the site monitoring inspection was to have a meeting with Dr. Adrian Brown, CC &V'S consultant to go over with the Division's David Bird and myself about the ongoing long term geochemistry investigations the operator had conducted to date in the diatreme. Dr Brown explained the results of both the dynamic and static investigations the mine had conducted to date and went in detail about the results. He also went in detail about the recent extensive sulfate study in Areqau gulch he conducted as result f the Division's request. The sulfate reading in both the compliance and monitoring wells have been showing an upward trend for the last 5 years. Until the last quarter's samples, the readings had never exceeded the numeric protection level set for the compliance well CRMW -3B63. He explained the long -term trends for sulfate in the drainage and his recommendations for the future. He also explained the extensive ground water testing being conducted in Grassy Valley to determine the connection with the diatreme and Carlton Tunnel discharge. 2) After the meeting the Division conducted the physical inspection of the existing valley leach facility and construction progress of the phase V leach pad area. The facility was active at the time of the inspection. While in the area, the following readings were taken from the high and low volume solution collection transducers. The Phase I high volume solution collection transducer # 1 was recorded at 20.8 , # 2 was at 20.9 and # 3 was at 17.9. The low volume solution collection transducer # 1 was at 0.28 and # 2 was at 0.47. The piezometers for the pond were at 35.6 and 28.6 feet. The phase II &III high volume solution collection transducer #4 was at 15.0, # 5 was at 16.9 and # 6 was at 14.8 . The low volumes solution collection transducer # 1 was at 0.52 and # 2 was at 0.64. The piezometer for the pond was recorded at 31.9. The phase IV high volume solution collection transducer # 7 was recorded at 11.9 ,# 8 was at 10.2 # 9 was at 10.3 and # 10 was at 9.6. The low volume solution collection transducer # 1 was recorded at 12.4 and # 2 was at 12.7 inches of hydrostatic head. The phase V high volume solution collection transducer # 311 was at 12.84, # 312 was at 13.33, # 313 was at 12.92 and #314 was at 13.34. The low volume solution collection transducer 41 1 was at 16.4 and # 2 was at 15.7 inches of hydrostatic head.( All other pressure transducer readings are in feet of hydrostatic head). The Phase IV C leach pad inter phase ditch was inspected and found to be in good repair. 3) The under drain discharge area was inspected. All the lower ponds were dry with the exception of the pond above the interceptor ditch, which was holding a very small amount of water. The NPDES discharge point AG 1.5 was inspected ad it was dry. The under drain discharge points 001 and south under drain were both discharging at the time of the inspection. The south under drain was discharging at 8 gpm and the 4 inch pipe or AG 01 was discharging at 0.179 gpm. No samples were collected at the time of the inspection. 4) The Phase V leach pad construction area was inspected.Drain cover was being placed along the south facing slopes along the west and east side of the lined area. AMEC QA.QC personnel were on site observing the deployment of the liner. Since the construction season began in late Aoril a total of 1.2 millon square feet of geomembrane has been deplyed and 1.8 million square feet of area has been lined with 12 inches of clay. The deployed liner was walked and inspected and found to be in good repair. Page 2 of 4