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2.04.7 <br />Water inflow into the mine is associated with sandstone channels or <br />fractures in the roof or flow from fractures in the floor. The pattern of water <br />inflow is one of steadily decreasing flow as the face mines through an area <br />and advances away from it. <br />Most areas dry up completely within several weeks of being mined. Where <br />areas don't dry up completely, water inflow subsides to less than 1 g.p.m. per <br />30 feet of entry to a few areas with 1-3 g.p.m. per 30 feet of entry. These <br />represent "damp" to "light drippers" as defined by NIOSH in their Coal Mine <br />Roof Rating System. The Bowie No. 2 Mine, D-Seam and B-Seam may also <br />encountered mine inflows from faults, fractures (if present) and perched <br />water bearing zones within the coal, the overburden, and the floor rock. <br />Faults are expected to yield more flow than either roof seeps or floor rock in <br />underground mining due to the secondary permeability created by the <br />fractures within the shear zones. Storativity within shear zones is usually <br />high which results in a higher initial inflow when the fault is first encountered <br />by underground mining and eventually slows to a rate dictated by the <br />permeability of the shear zone rock or slower up gradient medium. However, <br />the West Mains were mined though a fault which did not yield appreciable <br />mine inflows. <br />Mine inflows in the D-Seam are expected to subside when mining is <br />complete in the down dip portions of the mine and production shifts to the <br />west panels. See the Map 14, D-Seam Mine Plan for timing. <br />Mine inflows in the B-Seam will likely be similar to those experienced in the <br />D-Seam with inflows increasing as the B-Seam workings extend to the North <br />down dip. <br />w <br />PR-08 2.04 - 39 - 7/03 <br />A PPkovfD <br />4~zs~o3 <br />