2016-01-29_REPORT - C1992080 (2)

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OAKRIDGE ENERGY, INC. CARBON JUNCTION MINE (C-1992-080) ANNUAL HYDROLOGIC REPORT WATER YEAR 2015 The Oakridge Energy, Inc. Carbon Junction Mine (CDRMS Permit No. C-1992-080) is located approximately 2.5 miles southeast of Durango, Colorado. The mine is located on Ewing Mesa near the junction of Highways 160 and 550. The mine site is located in the upper drainage basin of Carbon Junction Canyon. Carbon Junction Canyon is an intermittent tributary of the Animas River. Much of the Carbon Junction Canyon drainage has a steep grade with a total drainage basin of 0.8 square miles. Hydrologic sampling and data collection was conducted at the Carbon Junction Mine between 1982 and 2006. The mine site was originally permitted by the Colorado Division of Reclamation, Mining and Safety (CDRMS), formerly the Colorado Mined Land Reclamation Division, in 1983 and re -permitted under Oakridge Energy, Inc. in 1993. Coal mining activity was initiated on the site on a minor scale. The extent of coal mining activities at the Carbon Junction Mine included opening both the North and South pits. Ancillary activity included construction of a permanently reclaimed spoils area, sediment control structures, topsoil stockpiles, and a pad for equipment. Permanent reclamation at the mine site was initiated in 1998 and completed in August 2006, with the only outstanding reclamation being the two sediment ponds and topsoil piles. After approval of Technical Revision 15 and Minor Revision 06 (demonstrating achievement of natural sediment generation levels on the reclamation) by CDRMS, reclamation of the sediment ponds and sediment control system commenced, with backfilling and topsoiling completed in December 2008. Revegetation of the reclaimed sediment ponds took place in April 2009. In March 2009, Oakridge Energy requested that quarterly sediment pond inspections be terminated, given that the sediment ponds had been reclaimed. In April 2009 CDRMS concurred with the request. With the approval of Technical Revision 16 in June 2010 approving the retention of the stabilized remaining topsoil stockpiles (4 and 7), there is no earthwork reclamation remaining at the mine. During discussions concerning Technical Revision 13 during 2005 and 2006, Oakridge Energy and CDRMS agreed to terminate groundwater (well) and surface water (spring and seep) monitoring at the mine site, effective in 2006. It was concluded that the limited mining activities at the mine did not negatively impact the hydrologic balance over the course of the operation. There is no remaining hydrologic monitoring at the mine. Quarterly sediment pond inspections were terminated with the reclamation of the sediment control system. With the reclamation of the sediment ponds, a request for termination of the CDPS discharge permit was submitted to the Colorado Department of Public Health and Environment (Health Department). The termination request was not processed by the Health Department. ;/.�,� ��, .;,^,`��-\`.-, /\,•,,.,..,,. � ��.�, .. ... Carbon Junction Mine Page 1 Annual Hydrologic Report for Water Year 2015