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Inspection Report - Problem 5 <br />The presence of sulfitic ore in the temporary ore stockpiles could cause this operation to be <br />classified as a Designated Mining Operation as defined in Rule 1.1(14). <br />Inspection Report - Corrective Action ' <br />The operator must, within 60 days, submit documentation the ore stockpiles do not have the <br />potential to produce acid mine drainage or documentation the ore stockpiles have been protected <br />from the potential to produce acid mine drainage or documentation the ore stockpiles have been <br />disposed of properly.. <br />Operator Response - Extension request for protection and disposal <br />August 24, 2009 <br />The Leadville Mill submitted a sample of the temporary ore stockpile material for analysis on <br />July 7, 2009. Evergreen Analytical, Inc. performed TCLP Metals, Leached analysis on the <br />material and Hazen Research, Inc. performed an acid base potential (ABPOT) analysis on the <br />material. This sample was a sealed split originally collected in February 2009, crushed and <br />composited by RDI, Inc. for other analysis. The TCLP analysis was performed on July 30, 2009 <br />and August 1, 2009. The ABPOT test was performed on July 27, 2009. Union Milling <br />Company received the results on August 12, 2009. <br />The ABPOT test indicates a potentially acidic material. The TCLP Metals, Leached analysis <br />detected lead in the material. The lead value is 5.Omg/L, exactly the toxicity threshold limit for <br />lead. All other tested metals (arsenic, barium, cadmium, chromium, mercury, selenium and <br />silver) are at undetectable limits. The test results note that the mercury analysis was performed <br />outside of the normal hold times. No other testing anomalies are noted. The test results are <br />attached. Since the lead value does not exceed the toxicity level, the material is not a hazardous <br />waste. <br />Based on the ABPOT test result, a extension of 30 days is requested to complete work to protect <br />the 3-stockpiles from the potential to produce acid mine drainage for an interim period; until the <br />3-stockpiles can either be placed in the on-site tailings storage facility (directly or through <br />milling) or combined with excess TSF construction material, blended to meet acceptable material <br />specifications and moved offsite for use or disposal. <br />Reinforced visqueen sheeting, approximately 20ft x 100ft sheets, will be placed over the piles, <br />edges folded and pinned, and held in place by tires, blocks, rocks and/or metal concrete forms. <br />The visqueen significantly reduces water infiltration into the stockpiles, minimizing acid mine <br />drainage potential. The water runoff from the visqueen is passed through a combination of <br />erosion and sediment control measures including natural minor depressions, constructed berms, <br />silt fence and vegetative filters.