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-zz- Surface water is also used for domestic, livestock, and municipal purposes. PROBABLE HYDROLOGIC CONSEQUENCES DF MINING A. The Golden Eagle Mine Mining activities at the Golden Eagle Mine began in 1916. Most of the activity has been in the development of surface facilities and mains in anticipation of future coal production. Hydrologic effects from this operation would be expected to increase with future mining activities. Most of these effects have been assessed in the applicant's hydrologic analysis provided in Exhibit 6 of the original permit application. Underground mining activities at the Golden Eagle Mine are expected to temporarily dewater the Maxwell and Allen coal seams (the coal seam aquifer). The average mine discharges measured during the third quarter of 1983 at the Golden Eagle Mine are higher than those measured during the period when the hydrologic report contained in Exhibit 6 was prepared. The present discharge rate is 30 gallons per minute (gpm), whereas the previously reported discharge rate was 15 gpm. This increased discharge rate can be attributed to lower water consumption, since the mine is inactive. During mining, water was consumed through absorption into coal exiting the mine and increased evaporation into the ventilation air. Currently, coal is not mined and ventilation air volumes are reduced. The applicant has estimated that inflow to the Golden Eagle Mine from the coal seam and roof would be between 159 gpm and 193 gpm depending upon the average transmissivity of the material encountered. This dewatering will create a drawdown of the piezometric surface in the coal seam in and around the mine. Drawdown of afoot or more could extend outward as far as 2 to 3 miles from the Golden Eagle .Mine (see Exhibit 6 of the Maxwell permit application). Undermining of the Purgatoire River might be expected to dep]ete flow in the stream/alluvial aquifer system. Using an estimated value of effective vertical permeability of 0.00021 ft/d, the downward flow of water from the body of alluvium was estimated to be 441 ft..i/d or only 2.3 gpm. This calculation was made for vertical leakage of surface water through the overburden to the mine workings. The overburden strata act as an aquitard, restricting the downward movement of water. This small water loss from the stream/alluvial aquifer system would have an insignificant impact on Purgatoire River flows or alluvial ground water levels. An inflow study for the Golden Eagle Mine was conducted in November, 1983. This study consisted of the mapping of all mine inflows, measuring or estimating inflow rates, and determining inflow sources. The information on Golden Eagle Mine inflows is contained in the WFC Submittal 3 and the Golden Eagle Mine Map submitted December 1, 1983. Fault and fracture systems have not been encountered in the Golden Eagle Mine to date. The applicant, however, anticipates encountering fault and fracture systems similar to those encountered in the adjacent New Elk Mine. The faults and fractures are dry in the New Elk Mine and are anticipated to be dry in the Golden Eagle Mine, as well. There are no mine inflows through the floor of the Golden Eagle Mine. Therefore, the mine is not impacting underlying aquifers.