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Mayo and Associates, LC <br />encountered in [he mine roof typically had initial discharge rates of 10 gpm or less and <br />~ flow rates declined rapidly (Mayo and Associates, 1996a). <br />Floor seeps likely issue from the Kenilworth Member of the Staz Point Sandstone <br />underlying mined coal seams. Some ofthis water is under considerable artesian pressure, <br />as evidenced by the well at SC-12G. The well penetrates the Kenilworth Member about <br />150 feet below the Rock Canyon Seam. The shut-in pressure of the well is 115 psi, <br />which means the pressure surface is about 115 feet above the base of the coal seam. <br />Appreciable dewatering of the Kenilworth Member via floor seeps did not occur, <br />because: 1) coal mining did not disturb the Kenilworth Member and, 2) the thick section <br />of $lackhawk Formation sepazating the coal and the Kenilworth has a low vertical <br />hydraulic conductivity. However as discussed below, where fault zone damage <br />intercepted the Kenilworth Member fault-related groundwater inflows occurred. <br />Considerable groundwater entered the mine from northwest trending faults located along <br />the east side of the mine. Initial discharge rates from the damage zone varied greatly, and <br />the dischazge declined substantially over time. One fracture flow site, UG-11E is of <br />particular interest in that the initial flow rate was 640 gpm in 1990 (Figure 6). The flow <br />rate declined to about 200 gpm during the first yeaz and has subsequently declined to less <br />than 100 gpm. The combined factors of isotopic composition, solute composition, and <br />discharge data suggest that much of the water up welled from the underlying Kenilworth <br />Member along the fault damage zone (Mayo and Associates, 1996a). The 3H content (0.0 <br />~~ <br />Evaluatioa of Potential Groundwater Inflows 23 February 24, 2004 <br />Associated with E Seam Mining, <br />West Elk Mine, Somerset, Colorado <br />