2016-08-22_INSPECTION - M1980244

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V NG W ,` O N • Newmont Mining Corporation 6363 South Fiddler's Green Circle,Suite 800 Greenwood Village,CO 80111 T 719-689-2977 F 719-689-3254 www.newmont.com SENT CERTIFIED, RETURN RECEIPT REQUESTED REcEIyED 7015-1660-0000-0779-7181 AUG 222016 DMSIOIV OF August 17, 2016 MI NI NO SAFE TION Mr. Timothy Cazier, P.E. Environmental Protection Specialist Colorado Department of Natural Resources Division of Reclamation, Mining and Safety Office of Mined Land Reclamation 1313 Sherman Street, Room 215 Denver, Colorado 80203 Re: Permit No. M-1980-244-, Cripple Creek & Victor Gold Mining Company("CC&V"), Cresson Project; — Response to DRMS Squaw Gulch Valley Leach Facility (SGVLF) Process Solution Storage Area(PSSA)piezometer question Dear Mr. Cazier: As a follow up to the corrective action request generated during the July 19, 2016 CC&V site inspection,we offer the following: Background The problem identified by DRMS was, "The SGVLF PSSA piezometer outside the drawdown cone area indicated the water level outside the pump drawdown area—17 feet lower than in the pump drawdown area, a trend opposite of what would be expected". The corrective action reqired by DRMS was, "CC&V must resolve to the Division's satisfaction the apparent discrepancy in the SGVLF PSSA piezometer limit with respect to the 80 percent storage capacity". Resolution At the time of the inspection, the piezometer outside the influence of the drawdown cone was calibrated to a different relative elevation due to the geometry of the liner sloping up from the caissons. The piezomenter was recalibrated on August 41h, 2016 to reflect the elevation of the four caissons in the PSSA which is 9336 feet. The 80%capacity elevation of the PSSA will remain at 9434 feet. With the newly calibrated elevation,the transducer readout appropriately measures water level to ensure readings are consistent with the 80%volume limit. Please note, Mr