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The impact of the proposed mine on ground water will be localized, with no <br /> significant impact expected on a regional basis. This is due primarily to the <br /> small quantity of ground water in the area. <br /> Water encountered within the mine will be utilized underground for dust <br /> suppression. As a result, only those inflows that temporarily exceed storage <br /> capacities and mine use requirements would potentially be discharged to the <br /> surface and lost from the ground water system. Pumping from approved mine <br /> water discharge locations ceased upon sealing of the"D" seam northern longwall <br /> district in 1996. The D Seam Dewatering System was reactivated to alleviate <br /> water levels within the"B" seam workings. Minor Revision No. 166 approved <br /> 1.37 acre expansion of the existing D Seam Dewatering pond to incorporate two <br /> additional sediment ponds to create a series of 3 interconnected sediment ponds. <br /> MR-166 was approved in October of 2015. With the approval of TR-68 and TR- <br /> 70, the Deserado Mine was approved for dewatering within the workings of the <br /> "B" seam. Excess water entering the mine workings is pumped to the surface <br /> where it is allowed to settle out or discharge through two series of sediment <br /> ponds, one being an artificial wetlands known as the B Seam Dewatering Pond <br /> System No. 1. The other is a series of three sediment ponds known as the B <br /> Seam Dewatering System No. 2. To the date of this findings document, only the <br /> B Seam Dewatering System No 1 and the D Seam Dewatering System have <br /> discharged into tributaries of Red Wash. <br /> Since January, 1997, prep plant thickener water has been disposed underground <br /> within down-dip, sealed sections of the "D" seam mine. No discernible effects <br /> on surface water or ground water quality are anticipated, although water levels <br /> will be reestablished sooner than would otherwise have been the case. <br /> Subsidence effects include fracturing of the material overlying the coal for a <br /> vertical distance of 30 to 40 feet due to caving of the roof material and surface <br /> subsidence and possible development of tension cracks on the surface due to <br /> differential settling. Observed ground water inflows during mining have been <br /> approximately 50 gpm. In fractured areas, increased flows of 100 to 300 gpm <br /> may be encountered for a short period of time. These flows will diminish as <br /> equilibrium is reestablished. Due to the low transmissivities of the aquifers, if <br /> caving should create a hydraulic connection from the mine to an aquifer within <br /> 30 to 40 feet of the coal, the additional inflow will be minimal. It is not probable <br /> that fracturing from the mine to the surface will occur as a result of subsidence <br /> and cause the flow of surface water to the mine. <br /> Subsequent to completion of mining, the ground water will slowly reestablish its <br /> pre-mining water levels. Due to the caving of the roof materials into the mine, an <br /> area of increased permeability will exist within the mine that will act as a "sump <br /> area" until equilibrium is established. However, due to the small quantity of <br /> water in the aquifers being discharged to the White River and its tributaries, the <br /> lack of ground water usage in the area, and the poor quality of ground water, <br /> xxx <br />