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This will short-circuit the flow of water through the coal seam <br />from its natural recharge area to its discharge area where the <br />coal seam daylights, as the water will be pumped out near the •.' <br />mine portal. This may result in an overall lowering of the <br />local water table, if there is vertical communication between <br />water bearing zones. Subsidence and the as:~ociated <br />rubbilization associated with mining ma.y increase the vertical <br />permeability in the overlying overburden and interrupt flows to <br />springs or wells located above the workings. There may be some <br />deterioration of water quality in the alluvial aquifers due to <br />recharge of surface water that has flowed through disturbed <br />areas or through the coal waste pile into the alluvium. <br />Changes to the surface water regime during mining will <br />include pumping of the river to provide water for mining, a net <br />increase in flow to the surface drainage system from the <br />pumping of mine inflows, and a change in the peak hydrograph of <br />waters flowing through the disturbed portions of they permit <br />area. Changes in the amount of flow will vary due to an <br />increase in the disturbance area and greater runoff, but <br />downstream, the presence of sedimentation ponds, will decrease <br />the peak and extend the release. of these waters to the North <br />Fork of the Purgatoire over a longer period of time: than a <br />typical storm event. Qualitative changes will include minor <br />increases in total dissolved solids {TDS), iron, and sodium <br />from mine water discharges, increased weathering of disturbed <br />areas, flow through the coal processing waste pile and <br />communication between the alluvium and the river. The <br />increased disturbance will result in an increase :in total <br />suspended solids (TSS) in surface waters within the disturbed <br />area, but an overall lower TSS level in surface waters below <br />the sedimentation ponds. Mine water discharges are treated for <br />elevated levels of TSS, but may result in effluEant with <br />slightly elevated levels of TSS. <br />Following the completion of mining, flooding of the <br />workings will allow the water table to rise again, and result <br />in the re-expression of springs. Physically, the overburden • <br />2.05-35 (Revised 04/27/94) <br />