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and the coal seam may act as a unified unit, due to the <br />• rubbilization associated with subsidence, and the recharge area <br />for this new, thicker, water bearing zone will increase to <br />include the area over the mine workings. Alternatively, the <br />recharge area may stay the same, as the fine grained sediments <br />in the intergrading sandstone, siltstone, and shale sequences <br />within the overburden may fill the fracture zones, thereby <br />healing them. <br />The water quality of the water filling the mine will <br />reflect the quality of the water observed within the coal seam <br />and within the mine water discharge. This will not materially <br />change the quality of the water acquired from the Maxwell seam, <br />but may result in a degradation of quality of some of the <br />original water bearing zones. <br />7 Alluvial waters adjacent to the disturbed areas will <br />a <br />~pi 1 ,,Q~show evidence of diminished water quality associated with mine <br />~~I waste piles, sedimentation ponds and other direct recharge from <br />surface waters running across the facilities area. The quality <br />• will improve with time, in conjunction with flooding of the <br />alluvium which will result both from leaching of the salts and <br />dilution. <br />The elevation changes associated with subsidence may <br />have long-term consequences for surface water flow patterns at <br />the site. Longwall subsidence can result in subsidence the <br />thickness of the coal seam down the center of the panel, with <br />less change in elevation along the edges of each panel. These <br />impacts are lessened with increasing overburden thickness. <br />This could cause ponding and depressions within stream channels <br />or irrigation ditches, or may damage water storage structures. <br />Long-term surface water quality impacts will probably not be <br />detectable. Mine water discharges will end, and the <br />predominant source of degraded waters will be derived from the <br />exchange of water between the alluvium and the river. <br />Dewaterincr Mapping of mine inflows has been performed <br />annually and the results have been included in the Annual <br />• Hydrology Reports. In 1993, Basin observed inflows at the <br />2.05-36 (Revised 04/27/94) <br />