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In excess of 500 gpm was estimated as initially issuing from the fracture zone. This flow exceeded the capacity of the mine's pumping system and a section of the mine was flooded for some period of time. Ultimately the flow from the fracture zone was controlled, and the flooded section cleared. Currently the water flow from the fracture zone totals somewhat less than 200 gpm. Such flow will reduce the potentiometric surface for the aquifer over a significant surrounding area. The apparent depth of the aquifer is, however, such that no wells in the area apparently produce from it. As a result no reduction of use of water from this aquifer has occurred or is anticipated for the future. 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 afoot 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). While essentially unavoidable, their impact is not significant with regard to 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 welts 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 througfi the overburden to the mine workings. The overburden strata acts as an aquitard, restricting the downward movement of water. This small water toss from the stream/alluvial aquifer system would have an insignificant impact on Purgatoire River flows or alluvial ground water levels. 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. -16-