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Well 81-19 (flowing) was tested by a "shut-in" testing procedure. Results <br />• of this testing yielded a value for permeability of 0.14 gpd/f t. <br />Recharge to the White Sandstone is expected to occur largely in the <br />area of outcrop, and possibly by infiltration from surface water bodies, <br />where conditions are favorable. Discharge to surface springs and streams <br />may also occur, where the sandstone lies near the surface, and where it is <br />saturated. Some discharge from the aquifer to the underground workings of <br />the No. 9 Mine is also probable. <br />3.4.2.5 Hydrology of the Coal Units <br />/ Two coal seams are presently being mined within the permit area. A <br />• / third coal seam, the "E" Seam, will be extracted in constructing the "E" Seam <br />/ access. The "P" seam is mined in the No. 9 Mine. Stratigraphically, this <br />seam lies between the Twentymile Sandstone and the White Sandstone. The <br />"F" seam is mined in the No. 5 Mine. Stratigraphically, this seam lies <br />/ between the Trout Creek and Middle Sandstone. The "E" Seam is located <br />/ approximately 40 to 100 feet below the "F" Seam. (See Figure III-1). Mine <br />inflows to the No. 5 Mine presently average approximately 830 gpm, and <br />inflows to the No. 9 Mine average approximately 250 gpm. Plots of the <br />mine discharges are presented on Figures III-l7h and 17i. <br />In their unbroken state, most coals have an intrinsically low <br />permeability. However, where these coals are fractured by naturally <br />occurring stresses or by induced stresses (associated with extraction of <br />adjacent coals), permeability can be increased substantially. There has <br />(REV. 2/14/86) <br />III-50 <br />