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Ground water quantity will be impacted during mining through the mining of the <br />recharge areas of aquifers and through depletions of ground water storage <br />(lowering of existing ground water levels) in aquifers by mine induced pit inflows. <br />Water which would ordinarily recharge the strata upgradient of the mine pit will be <br />diverted into the pit during mining. The recharge area within the permit area is <br />minor in comparison with respect to the entire recharge area of these aquifers up <br />and down gradient of the mine. Ground water currently stored within the aquifers <br />will be depleted by ground water flows from the aquifers into the pit (pit inflows) <br />as the mining operation moves down the dip of the coals. The applicant predicts <br />a maximum inflow rate of 200 gallons per minute which will lower water levels in <br />the aquifers. Following mining, the pumpage of pit waters will cease and a spoil <br />aquifer will be established. This spoil aquifer will recharge the bedrock aquifers <br />and ground water levels within the aquifers will approach pre-mining levels. <br />The depletion of recharge will impact the quantity of discharges from springs and <br />seeps downgradient of the mine, during and for a short period after mining. During <br />mining, some of the ground water which is tributary to the springs and seeps will <br />enter the pit, depleting spring and seep flows. Presently, springs and seeps from <br />the aquifers in the permit and adjacent areas are primarily dischazging to the stream <br />in Carbon Junction Canyon. Thus, there will be a depletion of stream flows. <br />However, pit inflow waters will be discharged to the surface stream, and the overall <br />impact to the quantity of surface water during mining will be minimal. Following <br />mining, ground water levels will return topre-mining levels. This will result in the <br />reestablishment ofspring and seep flows consistent with pre-mine rates. <br />The mining and processing of coal at the Carbon Junction Mine will impact the <br />quality of both surface and ground waters during and after mining. Mining will <br />disrupt the natural soils and rock strata in the disturbed areas of the mine operation. <br />Disruption of soils and rock strata will increase the exposure of previously <br />unexposed materials to both surface and ground waters. This exposure will result <br />in increased leaching and weathering of these materials, with a corresponding <br />increase in suspended solid and dissolved solid loads in surface waters and <br />increased dissolved solid loads in ground waters. <br />Suspended sediment levels will be minimized during mining by routing disturbed <br />drainages through sediment ponds. Sediment ponds will remain in place until <br />reclamation of the spoils and fill have been completed. <br />Total dissolved solid (TDS) levels in surface waters will increase during mining <br />through the leaching of exposed materials, concentration of TDS due to <br />evaporation in sediment ponds and mine pit, and through the operation of the coal <br />processing plants. The surface water discharges must meet the effluent limitation <br />imposed by NPDES permits prior to discharge. Therefore, the impacts to surface <br />water quality will be minimized during the mining operation. After the site has <br />n <br />