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-31- Undermining of the Purgatoire River might be expected to deplete-flaw 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. /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 Maxwell 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 Maxwell Mine inflows is contained in the WFC Submittal 3 and the Maxwell Mine Map submitted December 1, 1983. fault and fracture systems have not been encountered in the Maxwell Mine to date. The applicant, however, anticipates encountering fault and fracture systems similar to those encountered in the adjacent Allen Mine. The faults and fractures are dry in the Allen Mine and are anticipated to be dry in the Maxwell Mine, as well. There are no mine inflows through the floor of the Maxwell Mine. Therefore, the mine is not impacting underlying aquifers. The largest point source mine inflows were 3 to 10 gpm from 2 air shafts and 1 unsealed drill hole. These point source inflows are probably the result of dewatering of overlying perched aquifers penetrated by the drill hole and air shafts. The total mine inflow from point sources amounted to 16 gpm, or 53X of the total mine inflow (30 gpm). The remaining mine inflows were from weeping coal faces and weeping rock strata along the length of the rock slope incline. These weeping areas contribute inflows approximating 14 gpm, or 4TX of the total inflow. These weeps represent dewatering of the coal aquifer. The highest weep flows, totalling 11 gpm, are in the mine workings beneath the Apache Canyon stream channel. Mine workings beneath the Ciruela Canyon drainage only receive about 1 gpm from weeping coal faces. Development mining, to date, is not significantly impacting the overlying stream/alluvial systems. The Maxwell mine has undergone only development mining. Thus, there has not been any pillaring or longwall mining which would result in subsidence. There are no subsided areas in the Maxwell Mine from which the quantity of inflows resulting from subsidence can be measured. Empirical data on inflows to mined-out areas is, however, available from the Allen Mine. The calculated inflow rate per acre of mined-out workings at the Allen Mine is 0.03 gpm/acre. This value indicates a very low inflow per unit area, and represents inflows from sources other than subsided areas. Therefore, subsidence is not presently a significant source of mine inflows at the Allen Mine. Since the Maxwell and Allen Mines have similar geology and mining operations, subsidence inflows are not expected to be significant in the Maxwell Mine. Also, mining in the immediate future will be restricted to partial extraction and development mining at the Maxwell Mine. Therefore, subsidence-related inflows will not occur at this mine. Future mining plans include the use of longwall mining and pillaring in areas to the north and south of the Picketwire Valley, and partial extraction mining under the Picketwire Valley. Subsidence-induced mine inflows, therefore, would~be limited to areas outside of the Picketwire Valley.