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Prior to encountering the water bearing fracture zone in the Second Right entries, dewatering of the Maxwell and Allen coal seams (the coal seam aquifer) was anticipated to create a drawdown in the piezometric surface in the coal aquifer in and around the mine. Drawdown of a foot or more could extend outward as far as 2 to 3 miles from the Golden Eagle Mine (See Exhibit 6 of the Golden Eagle permit application). While essentially unavoidable, their impact is not significant as regards the quantity of water available in the area. No wells in the area of the mines have been identified as drawing water from either the Maxwell or Allen coal seam. Most domestic wells in the area produce from alluvial aquifers. The survey of water wells in the permit and adjacent area did identify some shallow windmill wells producing from bedrock aquifers above the Golden Eagle Mine workings south of the Purgatoire. These wells appear to result from localized, perched water tables or from minor coal seam aquifers in the area. The quality of the water is reported to be similar to that of seepage from coal and suggests the latter source. Golden Eagle workings lie approximately 200' under Windmill No. 6 (see Map 7). No seepage is reported for the workings at this point; the well remains functional. The relatively impermeable sediments separating the water source and the mine would appear to prevent any impact by the mine on shallow overlying bedrock aquifers. Undermining of the Purgatoire River might be expected to deplete 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.3/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 acts 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. The Golden Eagle Mine has undergone only development mining to this point. Thus, there has not been any pillaring or longwall mining which would result in subsidence. There are no subsided areas in the Golden Eagle 14ine 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 New Elk Mine. The calculated inflow rate per acre of mined-out workings at the New Elk Mine is 0.04 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 New Elk Mine. Since the Golden Eagle and New Elk Mines have similar geology and mining operations, subsidence inflows are also not expected to be significant in the Golden Eagle Mine. Future mining plans at Golden Eagle 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. -19-