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sufficient baseline water quality information to evaluate the <br /> changes in water quality that could result from the impacts of <br /> this refuse stockpile. Conductivity and TDS from samples of <br /> monitoring well GP-I showed slightly higher levels in 1986. <br /> However, this does not appear to be a continuing problem. <br /> Concentrations of iron during 1991 were higher than the <br /> baseline monitoring data, which the operator believes may be <br /> associated with B development waste. Concentrations of iron <br /> will be monitored to see if the elevated levels continue. <br /> A leachate study of the F Seam refuse was conducted and <br /> included in the application for the permanent refuse disposal <br /> site in Exhibit 51 of the permit application. In addition, the <br /> effects of B Seam refuse on leachate were also evaluated and <br /> can be found in Exhibit 56. The permeability contrast found in <br /> the pile will cause most of the leachate water to perch within <br /> the refuse pile and above the native soils. A shallow water <br /> mound will build within the pile and cause the water to migrate <br /> laterally to small seepage area at the edge site. During 1991, <br /> there were no visible flows from the pile toe and midsection <br /> underdrain. <br /> Upper Refuse Disposal Area - The upper waste rock pile was <br /> approved, with stipulations on June 14, 1986. This pile has <br /> not been constructed and construction is not proposed for this <br /> permit term. The final pile will cover approximately 40 acres <br /> and contain five million tons of coal reject and developmental <br /> waste rock. The primary predicted impact to ground water is <br /> the development of leachate from precipitation infiltration <br /> through the pile. The approved plan calls for the installation <br /> of five lateral subdrains to collect this leachate. The drains <br /> will help prevent the formation of a large perched leachate <br /> aquifer that may effect the stability of the pile. Additionally, <br /> the drains will intercept most of the leachate and prevent it <br /> from entering the shallow colluvial aquifers. The subdrains <br /> will daylight into surface channels where the leachate will flow <br /> to a sediment pond. As this pile is constructed, spoil wells <br /> will be installed. There are a number of stipulations which <br /> must be addressed prior to beginning the construction of the <br /> upper refuse pile. <br /> ii. Mitigation of Ground Water Impacts - <br /> The applicant anticipates no degradation of ground water <br /> quality during mining. The applicant will treat any mine water <br /> effluent as necessary to meet water quality standards prior to <br /> discharge and there will be no uncontrolled mine water <br /> discharge after mining is complete which might otherwise <br /> 33 <br />