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• per year. Potential reductions in groundwater flow as a result of mine <br />drainage and dewatering are approximately 4.7% of possible flows from the <br />affected strata within the groundwater basin. <br />Based upon this comparative approach, this reduction in flows is not <br />significant. It should also be noted that figures for Southfield Mine <br />inflow rates may be somewhat high reflecting the additional contributions <br />of vertical seepage through subsidence fractures from overlying abandoned <br />and flooded mine workings in the Vento Coal Seam. <br />It is anticipated that down-gradient reductions in groundwater flows will <br />be temporary and will be limited to the period of active mining and <br />dewatering and a relatively short interval thereafter. Upon completion <br />of mining, EFCI will abandon and seal the underground mine workings. With <br />relatively constant inflows to the workings, the mine will gradually flood <br />and recharge to down-gradient areas will be re-established. In addition, <br />there is the potential for localized increases in down-gradient flows as <br />• a result of increases in hydrostatic pressure as water builds up in the <br />abandoned workings and increased availability of water in the resulting <br />perched groundwater reservoir provides a source of recharge. <br />As EFCI has developed certain new mining areas there have been significant <br />increases in groundwater inflows, with measured flow rates well above <br />normal inflow rates experienced in other active working areas. These <br />elevated mine inflows have been documented in Southfield's Annual <br />Hydrology Reports and are believed to represent vertical seepage through <br />subsidence fractures which intersect overlying abandoned and flooded mine <br />workings on the Vento Coal Seam approximately one hundred feet above the <br />interval disturbed by Southfield's operations. If this is assumed to be <br />the case, Southfield's ongoing development and mining activities may <br />result in some dewatering of perched groundwater aquifers contained in <br />these overlying mine workings. <br />This potential hydrologic impact is not expected to be significant since <br />. the associated groundwater resources have no history of beneficial use. <br />Primary factors limiting use include depth, and the availability of <br />alternative surface and groundwater sources which are more accessible and <br />2.05.6-42 <br />