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on the hillsides where springs and seeps occasionally emerge as a <br /> result of landslides/sumps. <br /> 2. Probable Hydrologic Consequences of the West Elk Mine <br /> A determination of the probable hydrologic consequences of the proposed <br /> mining and reclamation activities at the West Elk Mine has been made by <br /> the applicant, and is found in Section 2.05.6(3) of the permit document. <br /> The operator has projected the impacts based on past experience, expected <br /> rates of water use and water discharge, hydrogeologic conditions associated <br /> with refuse disposal areas, location and extent of surface disturbance and <br /> hydrogeologic conditions associated with underground mine locations. <br /> During the past two permit terms, the West Elk Mine has mined the <br /> F Seam. During the next five years, West Elk will mine the B and <br /> E Seams. Activity in these seams will involve longwall mining methods, <br /> with very little or no activity in the F Seam. <br /> The Probable Hydrologic Consequences section of the permit is divided <br /> into two main subsections: Ground Water Effects and Surface Water <br /> Effects. <br /> a. Ground Water Effects <br /> There are no immediate demands on ground water in the vicinity of <br /> the West Elk Mine. Domestic water for the mine will be supplied by <br /> surface water from the North Fork of the Gunnison River, as there is <br /> limited potential to use ground water as a resource. The primary <br /> concern with ground water quality and quantity is the possible impact <br /> on springs, the potential for mine water discharge and ground water <br /> quality impacts in the mine facilities area. <br /> The underground mining methods in use at the West Elk Mine can <br /> affect ground water in two ways. First, development mining in areas <br /> where ground water is present in or near the coal seam can cause <br /> localized movement of this water into the mine workings. To date, <br /> ground water movement of this type has occurred in areas of low <br /> cover which are highly fractured (near outcrops and near stream <br /> channels) and where sandstone channels bearing water immediately <br /> overlie the coal seam. Secondly, retreat mining can cause subsidence <br /> and the fracturing of overlying ground water aquifers. Again, water <br /> usually moves into the mine workings. The permeability of the F and <br /> B Seam and overlying strata is very low and the areal extent and <br /> quantity of water stored in these units is small. <br /> Prior to construction of the mine, the applicant made an estimate of <br /> mine inflow by using preliminary pump test results and the <br /> McWhorter hydrogeologic model. The mine flow estimates assist in <br /> 30 <br />