2016-09-13_REVISION - M1980244 (3)

Home Browse Search

�c1 t,NEWMON T Newmont Mining Corporation v- TR85 6363 South Fiddler's Green Circle Suite 800 (1 Greenwood Village CO 80111 led T 719-689-2977 1 F 719-689-3254 ✓4 Violations: MV— www newmont com 1995-007, 1995-050, 1995-070 2015-0050,2016-035 SENT CERTIFIED, RETURN RECEIPT REQUESTED 7015-1660-0000-0779-7358 8 September 2016 RECEIVED Mr. Timothy Cazier, P.E. G `�G Environmental Protection Specialist �/$EP 13 2016 Colorado Department of Natural Resources Division of Reclamation, Mining and Safety DIVISION OF RECLAMATION Office of Mined Land Reclamation MINING AND WETY 1313 Sherman Street, Room 215 Denver, Colorado 80203 Re: Permit No. M-1980-244: Cripple Creek & Victor Gold Mining Company ("CC&V"); Cresson Project; — High Grade Mill Permanent Fresh Water Line Reroute—TR#85 r// L--- Dear Mr. Cazier: As requested in the Division of Reclamation, Mining and Safety's (DRMS) June 16, 2016 Inspection Report, Newmont Mining Corporation (Newmont) hereby submits the following Technical Revision (TR) #85 that proposes the installation of the permanent fresh water line reroute to supply water to the High Grade Mill (HGM). The design for the permanent fresh water line was developed by AMEC Foster Wheeler in response to a failure of a fresh water pipeline identified by Newmont on May 23, 2016 and is described below. A verbal notification was made to DRMS on May 24, 2016 and a written Update was provided on June 9, 2016. A temporary fresh water line, approved August 2, 2016 in TR #80, has been used in the interim to supply water to the HGM. Background On Monday, May 23, 2016 a loss of approximately 300 gallons per minute of fresh water was noticed at the mill. A pipeline inspection found a water leak at the toe of the East Cresson Overburden Stockpile Area (ECOSA) near where the fresh water line is buried under the facility. The fresh water was captured in the existing stormwater collection system; specifically in the ECOSA Toe Road BMP 20 Sump, which flows into the Rip Rap Ditch, and ends in the larger EMP 020 sediment pond. On Tuesday, May 24, 2016 a ditch was dug to ensure all freshwater flows directly into EMP 020 bypassing the other stormwater structures. An internal geotechnical inspection was completed on the entire face of the ECOSA dump determining the stability of the ECOSA is not compromised. Since the date of this event, daily inspections and weekly scans have been conducted by the geotechnical, environmental, projects, and operations departments. No change in conditions has been observed. On August 2, 2016 TR #80 was approved by DRMS which allowed for the installation of a temporary fresh water line. The installation of this line allowed Newmont the ability to shut off the Grassy Valley Pipeline which was feeding the broken pipeline. No water is currently