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Water moves downslope and discharges as seeps and <br />springs. It also appears that mine inflows are <br />controlled by the amount of precipitation (mostly <br />snowmelt), depth of overburden and location and extent <br />of fracture zones and not by the extent of the <br />underground workings. <br />Mountain Coal Company predicts that the West Elk Mine <br />will have no significant impact on the quality and <br />quantity of ground water and springs. Representative <br />water quality samples from wells located in the lower <br />coal member show that ground water is suitable for <br />discharge to the North Fork. <br />The B seam, which will be mined during the next five <br />year permit term, lies ten feet above the Rollins <br />Sandstone unit. The operator states that based on data <br />from the mining and reclamation plan and recent <br />drilling, it is reasonable to assume that the North <br />Fork of the Gunnison River recharges and receives <br />discharge from the Rollins Sandstone in a small area on <br />the northern edge of the West Elk property. It is <br />evident from available data that the Rollins behaves <br />similarly to the Barren member and Coal members in the <br />permit area except the extreme northern edge where it <br />has an alluvial contact with the North Fork. Ground <br />water pore pressure is expected to be 100 feet above <br />the Rollins Sandstone in the permit area. Since there <br />is a unit downward gradient, mining in the B seam will <br />not impact the Rollins Sandstone. <br />The Rollins Sandstone is considered a marginal aquifer <br />in terms of yield and water quality and, to MCC's <br />knowledge, has no points of usage in the mine <br />vicinity. Review of data for the region indicates that <br />none of the other mines in the area have monitored the <br />Rollins Sandstone. Since the Somerset Mine has been <br />active since 1906, any potential for severe water <br />quality impact would probably be evident by this time. <br />The water quality data for R-l, a well completed in <br />Rollins Sandstone and drilled by Mountain Coal Company <br />in 1976, indicates total dissolved solids generally <br />outside the range acceptable for drinking water. <br />The majority of Mountain Coal Company's hydrologic <br />monitoring concentrates on mine water discharges and <br />wells associated with B seam mining. Disturbances and <br />changes to water quality, if they occur, will be <br />manifested in B seam discharge water and B seam <br />monitoring wells prior to any potential impacts to the <br />Rollins Sandstone. The B seam is separated from the <br />Rollins by siltstones, shales, and another coal seam. <br />It is unlikely that the Rollins Sandstone would be used <br />-38- <br />