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<br />The mapping of mine inflows indicate that faults and fractures are not a <br />source of mine inflows. No point source inflows were observed along <br />faults and fractures. This indicates that faults and fractures are <br />healed with impermeable clays and/or are not vertically extensive. <br />Major point source mine inflows are related to 2 air shafts and 1 power <br />access bore hole. These sources account for approximately 8 gpm of the <br />total 123 gpm of inflow to the mine. These inflows represent dewatering <br />of perched overburden aquifers, which were intersected during boring <br />operations. <br />The coal seam was observed to be weeping at 3 different mine faces. <br />These weeping faces are contributing 5 gpm. These inflows represent the <br />dewatering of the coal seam aquifer. <br />One channel sandstone was encountered in the 1 P.S, workings which <br />contributes 3 gpm. This channel sand is probably draining ground water <br />from the coal seam. <br />Only one minor inflow was observed issuing from the mine floor. The rate <br />of inflow was estimated to be 1 gpm. This indicates that the New Elk <br />Mine is not significantly impacting the quantity of ground water in <br />underlying aquifers. <br />The major source of mine inflows measured in the New Elk Mine are from <br />weeping seals which close off old mined-out areas. The total quantity of <br />mine inflows from mined-out areas was measured to be 106 gpm. The total <br />area which contributes to these inflows is about 2800 acres. The <br />calculated inflow rate per unit area for the mined-out workings is 0.04 <br />gpm/acre. The total inflow rates measured for the mined-out areas would <br />be the sum of the inflows from weeping coal faces, subsidence-induced <br />fractures, any unsealed drill holes in these areas, and vertical leakage <br />through overburden strata. The major source of mine inflows in these <br />areas is probably the weeping coal faces, resulting from dewatering of <br />the coal aquifer. Coal faces on the western edge of the New Elk permit <br />boundary are near the coal seam aquifer recharge area. These workings <br />could quickly capture any recharge waters and channelize flows of water <br />dawn the dip of the coal seam to the seals, where the inflows were <br />measured. Weeping coal faces were also observed as a major source of <br />inflow in the Golden Eagle. <br />After mining ceases, water will be depleted from the stream/alluvial <br />aquifer systems which will not be returned. This depletion will persist <br />as the mine workings fill with water. Once the mine workings have <br />filled, surface flows and alluvial ground water flows should closely <br />approximate the flows which existed before mining occurred. <br />The water discharged from the New Elk Mine is a sodium bicarbonate type <br />water with an average pH of 7.8 and an average total dissolved solids <br />content of 1138 mq/1 (See Exhibit 10 of renewal application). Under <br />Q7-10 low flow conditions of 1.6 CFS in the Middle Purgatoire, an average <br />maximum discharge of 180 gpm from the mine would increase TDS value in <br />-23- <br />