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the Colorado Mined Land Reclamation Board for Hard Rock, Metal, and Designated <br />Mining Operations ("Rules"), specifically designed, engineered, and certified to <br />permanently contain fine-grained mill tailings produced from milling rock to protect <br />surface water and groundwater resources from acid forming material and acidic <br />leachate. The tailings impoundment liner design was signed and sealed by a <br />licensed Colorado professional engineer. The Division accepted certification of the <br />tailings impoundment on September 7, 2011. Placing mine dump materials onto <br />the liner or any acceptable method of placing mine dump materials onto the liner <br />were not addressed in any of the analyses of the tailings impoundment liner. <br />4. The approved Mining Plan for the site, Exhibit C to permit number M- <br />2009-076 ("Mining Plan"), provides that the EPF tailings impoundment "will be <br />built up on the down-slope face from the coarser fraction of the waste stream by <br />hydraulic placement and hydraulic classification." <br />5. The Mining Plan states, under the Important Impoundment Stability <br />Measure heading, among other things: "Carefully adhering to the operating and <br />embankment construction parameters previously set forth ensures proper impoundment <br />stability behavior. These parameters prescribe a method of tailings impoundment <br />technique, dewatering practices, and embankment geometry relationships." <br />6. The approved Environmental Protection Plan for the site, Exhibit T to <br />permit number M-2009-076, stated: "The proposed operation is essentially <br />converting an area containing pre-existing abandoned waste rock into an <br />impoundment for processed tailings that are inert and void of acid forming material." <br />7. On September 17, 2015, the Division conducted an inspection of the <br />site ("September 2015 Inspection"). Patrick Maher attended the inspection on <br />behalf of Operator. During the inspection, the Division observed that Operator had <br />placed mine dump materials on the tailings impoundment liner. Mr. Maher <br />informed the Division that he observed weathering of the exposed portion of the <br />liner. In order to protect the liner from further weathering, Operator covered the <br />liner with on-site mine dump material which included country rock, waste rock, and <br />soil. The Division observed that the material placed on the liner consisted of large <br />angular pieces of rock up to twenty-four inches in diameter and pieces of timber <br />from two to six feet in length. The Division cited a problem in regard to the <br />placement of mine dump materials onto the tailings impoundment liner. <br />8. In the report of the September 2015 Inspection, the Division noted that <br />the impoundment liner was not designed for unprocessed waste rock. The Division <br />also noted that the placement of mine dump materials onto the liner and the <br />method of placement was not accounted for in any of the analyses in the design of <br />the liner, and as a result the Division cannot be certain that the liner is fully intact. <br />Venture Resources, Inc. <br />Hukill Gulch Millsite, M-2009-076 <br />MV -2016-007 <br />2 <br />