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• <br /> <br />down-gradient from the VLF and the external storage pond and provides an <br />effective means of managing near-surface alluvial groundwater and further <br />protecting surrounding water resources. <br />CC&V has adopted a 0.2 mg/1 WAD cyanide limit to protect local ground water <br />resources. This is also a requirement of the State Mining Permit. Two ground <br />water compliance monitoring wells are located downgradient of the VLF and the <br />pumpback system. Monitoring data indicate that no groundwater exceedances <br />have occurred for cyanide. <br />CC&V operates a VLF and does not generate any tailings. It is understood that <br />some tailings historically treated with cyanide were present in the VLF footprint <br />area and were partially moved and regraded as part of the basin preparation. <br />No mill tailings were used for remediation of underground workings, however, <br />because they did not have the necessary geotechnical properties to be used as fill. <br />Filling of historic mine workings under the VLF typically involved backfill with <br />cemented development rock, coarse shaft backfill, cement plugs, and cover and <br />grading using structural fill. Construction records indicate that similar <br />engineered practices were employed prior to placement of sub-base or liner <br />installation at the VLF. QA/QC records were reviewed for all four phases of <br />leach pad construction and found to be acceptable. <br />Monthly reports required by the Colorado Department of Public Health and <br />Environment for the past 12 months were reviewed. There were no recorded <br />events during this timeframe in which cyanide concentrations in ground water <br />exceeding 0.20 mg/1 (WAD); beneficial uses have not been impaired. <br />The surface water standard for Arequa Gulch is 0.020 mg/1 (WAD), and has not <br />been exceeded. Arequa gulch is normally dry, however, and a review of <br />environmental records shows that no surface water has been measured at the <br />compliance point since 2002. <br />4.7 Provide spill prevention or containment measures for process tanks <br />and pipelines. <br />• <br />The operation is: <br />Cresson Project <br />Name of Mine <br />10 September 2007 <br />Date <br />^ in full compliance <br />^ in substantial compliance <br />^ not in compliance ...with Standard of Practice 4.7 <br />-'~~~ ~ <br />~--~- <br />Signature of Lead Auditor <br />Page 19 of 41 <br />