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Reclamation Feasibility Report - Virginia Canyon <br /> <br />• <br />Water Quality Impacts <br />The waste rock piles at this site both exhibit severe erosion. In addition, the vegetation below the <br />waste rock has been killed for almost 600 feet below the piles. All vegetation has been killed for <br />approximately 200 feet below the piles, and the herbaceous vegetation has been killed almost to the <br />road below. Erosion appears to be principally from water flowing onto the waste rock from above. <br />The waste rock from these mines is extremely acid forming and has very high concentrations of <br />leachable arsenic and iron with high concentrations of leachable copper and lead. Results from the <br />2:1 leachate analysis are given below. <br />Site #80 <br />pH <br />S.U. Total Acidity <br />m l As <br />b Cd <br />b Cu <br />b Fe <br />b Mn <br />b Pb <br />b Zn <br />b <br />2.18 3380 1900 67 4900 670000 1800 6200 12000 <br />There is probably little direct erosion of the mine waste into stream. The stream is located about <br />700 feet from the upper pile and 500 feet from the lower pile. There may be some movement of <br />metals through leaching into the shallow ground water table during spring snowmelt. <br />Reclamation Measures <br />Because of poor access, the available reclamation options are limited. Removal of the mine waste <br />or in-situ cementation would require construction of a road into the site, which would result in a large <br />scar. Because of poor access, the recommended reclamation method is to construct diversions <br />around the site, and neutralize the waste rock with lime and limestone. The diversion ditches can be <br />constructed by hand, or by a small excavator that can negotiate through the trees with minimal <br />• damage. <br />65 <br />Figure 35. Upper Clarissa Adit and Shaft (Site #80)