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lower waste pile. For the analysis, MCC assumed a 10-year <br /> 7-day low flow in the river, maximum leachate production, and <br /> that all of the leachate would reach the river undispersed and <br /> undiluted. The results of the analysis showed that the discharge <br /> would not jeopardize any receiving stream standards. The <br /> amount of discharge is so low in relation to the stream flow <br /> that there will be no adverse effects to the hydrologic balance <br /> outside the permit area. <br /> Upper Refuse Disposal Area - Potential impact to local surface <br /> water hydrology will be similar to that of the Lower Refuse <br /> Disposal Area and is discussed above. However, the upper pile <br /> has not yet been constructed and construction is not planned for <br /> this permit term. <br /> ii. Mitigation of Surface Water Impacts - <br /> Impacts to surface water during the five-year permit term are <br /> expected to be minimal. The operator predicts that no <br /> degradation of water quality in surface streams is expected. <br /> Drainage from the waste pile, mine water, and runoff from all <br /> disturbed areas will be passed through a sediment pond prior to <br /> discharge to the North Fork of the Gunnison River. <br /> The West Elk Mine has an extensive water monitoring plan to <br /> monitor surface water quality and quantity. West Elk is <br /> currently monitoring eleven stations. Seasonal (three times per <br /> year) water samples are taken at all surface water monitoring <br /> stations. Parameters measured include pH, conductivity, <br /> temperature, total dissolved solids, total suspended solids, total <br /> iron and total manganese. More specific details regarding <br /> MCC's water monitoring plan can be found beginning on page <br /> 2.05-57. <br /> 3. Summary and Findings <br /> The Division has examined the Probable Hydrologic Consequences due to <br /> mining operations for the ground water and surface water systems at the <br /> West Elk Mine. The Division finds that underground mining at the West <br /> Elk Mine will not have a significant impact on these water systems. The <br /> mine will take the necessary measures to ensure that mining will not affect <br /> the hydrologic regime (2.07.6(2)(c)). <br /> IV. Topsoil <br /> Baseline soils information can be found in Section 2.04.9 in Volume 1 in the permit <br /> document. A suitability analyses of the topsoil was performed before the site was <br /> disturbed. In most areas topsoil quality as seedbed material is considered moderate <br /> 43 <br />