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until a maximum of 233 ft3 per day (1.24 gpmi near the end of <br />the five year period when the maximum cross sectional area is <br />available for flow. The total amount o4 inflow is small due <br />to the minimal transmissivity of the coal seam and the small <br />size of the operation. <br />The flow into the line sink with recharge was taken as the <br />total inflow from the Harvey Gap subcrop. This flaw also <br />increased throughout the five year mine life to a maximum of <br />91 ft3 (0.47 gpm or 0.063 cfs?. This depletion is 0.2% of the <br />maximum flow of ~ 40 cfs released from the dam. The depletion <br />is 3.2% of the minimum flow of ~ 2 cfs released from the dam. <br />The depletion is negligible. <br />The radius of influence is bounded on the west at 400 feet by <br />the subcrop. The eastern line sink reches a maximum distance <br />of 237 feet. The line dip sink distance becomes negative <br />since the radius of influence is calculated from the original <br />position of the sink and the mine progression in the down dip <br />direction is faster than the expanding distance of influence. <br />The small transmissivity and size of the oeration result in a <br />small area close to the mine being influenced. No ground <br />water uses are affected within this distance of influence. <br />Hydrology - Water Quality Impacts. No impacts to ground water <br />• qualit>• are anticipated since flow is into the mine area and <br />then is used in the mining operation or pumped to the <br />sedimentation pond. <br />The impact of the mine on Harvey Gap was evaluated for three <br />possible impacts: <br />1. Flow depletion through ground water interception by <br />the mine <br />2. Discharge of the sediment pond to Harvey Gap <br />3. Runoff from the coal refuse pile <br />As discussed in the Modeling section, the depletion of flow <br />due to the mine is 0.2% of the maximum flow and 3.2 % of the <br />minimum flow in Harvey Gap. Since no quantity of water or <br />dissolved solids is being added to Harvey Gap, no water <br />quality impact is predicted. <br />The inflow to the mine is small so the quantity will be used <br />in the mining operation or pumped to the sedimentation pond. <br />Runoff from the site will be flowing to the pond. The ponds <br />are designed for the 24 hour containment of the 10 year-24 <br /> <br />63 Revised 5/87 <br />