2012-04-19_REPORT - M1977004 (2)

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Pitch Reclamation Project Colorado Mined Land Reclamation Board — 2011 Annual Reclamation Report EXECUTIVE SUMMARY Homestake Mining Company of California (Homestake) operated the Pitch Uranium mine in Saguache County, Colorado from 1979 until 1984. The mine extracted uranium ore and trucked it to their mill in Grants, New Mexico. In 1984, operation was suspended and the mine was placed in a care and maintenance status. Incremental reclamation and revegetation of mine site disturbances were performed throughout the period of 1985 to 1993. In 1993, Homestake initiated the process of permanently closing the mine. Since 1993, closure and reclamation activities have included pit wall grade -down and partial backfilling of the North Pit to reduce pit wall movement, the contouring and revegetation of the approximately 230 acres of disturbed area, construction of a plug in the Pinnacle Adit to reduce seepage and improve water quality, monitoring of slope stability in the North and South pits; monitoring of the phreatic surface in the Indian and Tie Camp waste rock dumps, construction of surface water controls, and the dismantling and removal of the Radium Treatment Plant (RTP) as well as associated foundation materials and soils that were placed in the Tie Camp Creek Disposal Cell. During 2011, Homestake maintained the remaining mine facilities and fulfilled permit and license related compliance programs which included the following activities: • Monitored water quality discharged at the point of compliance (POC), SW -33, and submitted monthly discharge monitoring reports to the Water Quality Control Division of the Colorado Department of Public Health and Environment (CDPHE) per the requirements of the Colorado Discharge Permit System (CDPS) permit #CO- 0022756 renewal effective January 1, 2010; • Continued activities under the conditions of the Radioactive Materials License (RML) issued by the Colorado Department of Health and Environment — Hazardous Materials & Waste Management Division (Permit #150 -01, Amendment 14); • Continued improvements in the drainage, stabilization, and reclamation in the constructed wetlands area (site of the former Radium Treatment Plant); • Erosion repairs on the northwest side of the Indian Creek rock dump near the clay stockpile and low grade stockpile; • Grading of tension cracks on the East Wall of the South Pit and in the slump area of the South Pit to eliminate pooling of water; • Grading on the second bench of the Tie Camp Creek rock dump to reduce erosion; • Repair work on the Tie Camp Creek Disposal Cell including grading for drainage control, harrowing, scarifying and seeding to enhance erosion control and drainage management on the top of, and around, the disposal cell; • Geotechnical monitoring of pit wall slopes on the south and east walls of the North Pit, the east wall of the South Pit and the Indian Creek and Tie Camp Creek waste rock dumps; • Monitoring of Tension cracks above the east wall of the North Pit; • In August both piezometers IC10300 and IC10370 were sealed and were replaced with two new piezometers IC10300R and IC10370R at approximately the same locations. • Monitoring of the groundwater levels in piezometers within the area of Pinnacle workings and monitoring of springs and seeps potentially influenced by the resaturation of the historical underground workings; Pitch 2011 Reclamation Finalreport 19Apr12 Doc ES -1