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<br />Major point source mine inflows are related to two air shafts and one <br />power access bore hole. These sources account for approximately 8 gpm of <br />the total 123 gpm of inflow to the mine. These inflows represent <br />dewatering of perched overburden aquifers, which were intersected during <br />boring operations. The coal seam was observed to be weeping at three <br />different mine faces. These weeping faces are contributing 5 gpm. These <br />inflows represent the 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 i gpm. This indicates that the Mew 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 <br />0.04 gpm/acre. The total inflow rates measured for the mined-out areas <br />would be the sum of the inflows from weeping coal faces, <br />subsidence-induced fractures, any unsealed drill holes in these areas, <br />and vertical leakage through overburden strata. The major source of mine <br />inflows in these areas is probably the weeping coal faces, resulting from <br />dewatering of the coal aquifer. Coal faces on the western edge of the <br />New Elk permit boundary are near the coal seam aquifer recharge area. <br />These workings could quickly capture any recharge waters and channelize <br />flows of water down the dip of the coal seam to the seals, where the <br />inflows were measured. Weeping coal faces were also observed as a major <br />source of 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 />At the New Elk Mine site, several historic and existing coal refuse piles <br />are located on the alluvial flood plain of the Middle Fork of the <br />Purgatoire River. None of these is now being used by the mine. As a <br />result of Permit Revision 1, a new refuse disposal area was established <br />north of the mine across Highway 12. Processing waste is carried to this <br />facility by means of a conveyor system from the prep plant. This is the <br />only coal waste disposal facility a rrently in use at the New Elk Mine. <br />Runoff and seepage from the new refuse disposal facility is contained by <br />Pond no. 8. This pond has never discharged since its construction. <br />Consequently, except in a rare case of pond discharge, no impact on water <br />quality in the Middle Purgatoire should be made by runoff and seepage <br />from this facility. <br />-20- <br />