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San Luis Project <br />CDRMS Annual Report <br />March 23, 2011 <br />Page 3 <br />As specified in TR-31 and TR-32 monitoring plans, monthly and quarterly pond analysis <br />were conducted and reported to the Division. <br />The tailing embankment piezometers were inspected monthly. Each of these installations <br />either remained dry or contained less than 12 inches of accumulated water within the <br />piezometer casing. Results of these inspections were reported to the Division in monthly <br />reports. <br />The tailing collection pond leak detection system was evacuated monthly and quarterly <br />sampled and analyzed in accordance with the applicable technical revision monitoring <br />plan. Laboratory analytical reports were submitted to the Division upon receipt from the <br />laboratory. The 2010 collection pond leak detection system return flow rates ranged from <br />21 to 26 GPAD. <br />Water treatment plant sludge removal was conducted twice during the 2010 calendar <br />year; approximately 232 tons of sludge were removed from the water treatment pond and <br />placed to the drying pad containment and subsequently to the tailing facility for final <br />placement. <br />Technical Revisions/Permit Amendments <br />BMRI continued implementations of TR-26 as approved on May 23, 2000. BMRI has <br />been actively managing the West Pit and Rito Seco alluvial hydrologic systems since July <br />1999, and the water management techniques developed in TR-26 has been fully <br />implemented accordingly. The water management techniques employed since the <br />submission of TR-26 to the Division has reversed and maintained the West Pit hydrologic <br />gradient at a groundwater elevation (8582 ft amsl) below the Rito Seco stream channel <br />elevation since February 8, 2000 eliminating any surface water expressions. <br />Groundwater recovery wells M-32 and M-33 installed during the 2000 calendar year to <br />capture and remove contaminates contained in the Rito Seco alluvial groundwater system <br />continued to be operated throughout the 2010 calendar year. Groundwater recovered <br />from these wells was pumped back to the West Pit water treatment plant, treated and <br />discharged in accordance with the Colorado Department of Public Health and <br />Environment discharge permit. Groundwater elevations in the vicinity of these wells <br />were maintained below an elevation of 8540 ft amsl to ensure groundwater capture and <br />prevent down gradient migration of contaminates contained within the Rito Seco alluvial <br />groundwater system. <br />During 2010, BMRI submitted or withdrew no permit amendment(s) or technical <br />revision(s).