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Golden Eagle Mine of 208 gpm of which 74 gpm came from the roof <br />and floors, 34 gpm came from leaks associated with dri:Ll holes <br />•~ <br />and shafts, and 100 gpm came from a fault. Mine water inflow <br />is collected in sumps and discharged from the mine by pumping. <br />The average monthly discharge from the mines has ranged from 15 <br />gpm to 308 gpm averaging 118 gpm over the last 6 year:a. When <br />relating calculated discharge to the inflow :results, <br />correlation of inflow to discharge is r~=_latively close. If the <br />period of discharge during the months of August are examined <br />(that month in which the inflow studies were conducted) results <br />of inflow vs discharge are equal. Additional underground <br />seepage which cannot be measured is possibly contributing <br />somewhat to the rate of discharge. <br />The Maxwell, Blue and Red coal seams are the predominant <br />sources of non-fault related inflow, with minor contributions <br />from channel sands with localized areal extent. Examination of <br />representative drill hole data acquired since 1980 ;suggests <br />that the water level can vary from 195.4' to 484.2' above the <br />top of the Maxwell Coal. The drawciown analysis found in y <br />.. <br />_ <br />Exhibit _6 was performed using a range of saturated thicknesses. <br />a_ <br />Coal seam transmissivity values from t <br />he WWI. Report <br />_ <br />ranged from 0.56 to 1.98 ft2/day, with an average coal <br />transmissivity of 1.27 ft2/day. These: established the three <br />cases (I, II, and III). Coal permeability was set at 2.1 x 10-` <br />ft/day. The effective saturated thickness of the leaking <br />overburden aquifer .was set at 195.4 ft for Case A, and 484.3 ft <br />for Case B in the 1994 Greystone Report in Exhibit 6. The <br />leakance values ranged from 722 ft to 2:137 ft with discharge to <br />the mine per foot of perimeter ranged from 0.152 to 0.448 <br />ftZ/day. These results were then applied to the perim~=_ter and <br />areal extent of the mine, to determine mine inflow i=rom the <br />face and roof respectively. The perimeter of the life-of-mine <br />is 52,000 feet and the areal extent i.s estimated to be 4.34 <br />square miles, or 1.21 x 108 square feet.. Three scenarios were <br />examined: the existing configuration oi' the Golden Eagle Mine, <br />the configuration for the current permit term, and the life-of- • <br />2.05-37 (Revised 04/27/94) <br />