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Lohman's (1952) formula for nonsteady flow to a well of constant drawdown, <br />• and (3) McWhorters (1981) methodology for calculating inflow to mines from <br /> a coal seam. Because Empire Energy has no direct measurements of the <br /> hydrologic properties of the coal; estimates have been made. <br /> Transmissivity (i) and storativity (S) values for equivalent coal beds at <br /> the nearby Northern Coal Mine were obtained (Table 19). Specific yield <br /> (Sy) was estimated to be 0.10. Although the coal thickness (b) can vary, <br /> an average thickness of 12 feet was used. These values were then applied <br /> to the McWhorter method and used to try to duplicate the past measured <br /> flows in the No. 9 Mine. The values of T and 5 were varied until a <br /> reasonable match to observe flows was obtained. The values of T and S <br /> that produced the best were 30 ftz/day (225 gpd/ft.) and 0.002 <br /> respectively. It was found that the values for transmissivity and <br />• storativity used for the No. 9 Mine produced a reasonable fit to observed <br /> flows in the No. 5 Mine as well. These values are 225 gpd/ft and 0.002 <br /> respectively. <br />/ Because the "E" Seam is geologically similar to the "F" Seam (No. 5 <br />/ Mine) and "P" Seam (No. 9 Mine), it is assumed to have similar hydrologic <br />/ properties. Since the average thickness of the "E" Seam is approximately <br />/ 10 feet at the "E" Seam access areas, the transmissivity of the seam is <br />/ estimated to be ten - twelfths of the "F" and "P" Seam transmissivity: 25 <br />/ ftz/day (187 gpd/ft). Also, because the "E" Seam access is at the subcrop <br />/ of the seam, the area is partially to completely unsaturated. Drill hole <br />/ DR-4 encountered no water in the seam. Based upon this information at <br />/ least one-third of the "E" Seam access area is unsaturated. The estimated <br />/ average head in the rest of the area is only 20 ft. Therefore, during <br />(REV. 2/14/86) <br />III-71 <br />