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disposal areas, location and extent of surface disturbance and hydrogeologic <br /> conditions associated with underground mine locations. <br /> During the first two permit terms, the West Elk Mine mined the F Seam. <br /> During the third permit term, West Elk mined the B Seam exclusively. <br /> Activity in these seams involve longwall mining methods, with very little or <br /> no activity in the F Seam. During the next permit term West Elk plans to <br /> mine the B-seam for most of the period, with access to and development of <br /> the E-seam beginning toward the end of the 5-year permit term. <br /> The Probable Hydrologic Consequences section of the permit is divided into <br /> two main subsections: Groundwater Effects and Surface Water Effects. <br /> a. Groundwater Effects <br /> There are no immediate demands on groundwater in the vicinity of the <br /> 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 groundwater as a resource. The primary <br /> concern with groundwater quality and quantity is the possible impact on <br /> springs, the potential for mine water discharge and groundwater quality <br /> impacts in the mine facilities area. <br /> The underground mining methods in use at the West Elk Mine can <br /> affect groundwater in two ways. First, development mining in areas <br /> where groundwater is present in or near the coal seam can cause <br /> localized movement of this water into the mine workings. To date, <br /> groundwater movement of this type has occurred in areas of low cover <br /> which are highly fractured (near outcrops and near stream channels) <br /> and where sandstone channels bearing water immediately overlie the <br /> coal seam. Secondly, longwall mining can cause subsidence and the <br /> fracturing of overlying groundwater aquifers. Again, water usually <br /> moves into the mine workings. The permeability of the F and B Seam <br /> and overlying strata is very low and the areal extent and quantity of <br /> 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 McWhorter <br /> hydrogeologic model. The mine flow estimates assist in identifying the <br /> magnitude of mine discharge and to assess the potential impact on <br /> natural patterns of groundwater recharge and discharge. <br /> In the past, the West Elk Mine has experienced three types of mine <br /> inflows. The first type of inflow is due to primary permeability which <br /> is groundwater flow through the competent portions of the F Seam and <br /> lower Barren Member. The second type of inflow occurs in the coal <br /> 36 <br />