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' 2 <br />' According to Bear's reclamation contractor (per MCC interview), water apparently continued to <br />flow into the drawdown tunnel and was pumped from the tunnel until and including the time the <br />tunnel was being demolished and backfilled, just a few weeks prior to the appearance of the flow <br />' at the Edwards Mine portal area. <br />MCC understands that it would seem important that MCC had predicted in its own PHC revision <br />' application that the Edwards Mine portal would be one of the various locations that water would <br />express, if inflows into Bear occurred from the NW Panels sealed sump. Although the Edwards <br />' Mine portal is the first listed in the PHC of potential outflow locations, based on elevations <br />available from the Bear's final mine map, it would not be the first location where inflows from the <br />sealed sump would flow. Instead, any inflows would more likely first flow to and accumulate in <br />' the northeast (and lowest, down-dip elevation) portion of the Bear B-seam workings. It is also <br />important to emphasize that all portal locations for the Bear C-seam and B-seam mines were <br />listed as potential mine water discharge locations, as the seal materials were assumed to be less <br />' dense and more porous (and at least one contains a pipe) than the in-situ outcrop barrier, thus <br />would be the paths of least resistance for any water Row. No flows have been observed at the <br />other portal locations to date. <br />' The following responses are presented under the headings and in the same order as the <br />discussions and questions in your March 30, 1998 letter. <br />1 Hvdrolo is Impact Monitoring - <br />' 1) Prior to starting longwall mining of the 11 NE panel, MCC was able to develop two entries <br />from the northwest corner of the 11 NE panel toward the northeast corner ofthe NW Panels <br />sealed sump and complete one in-mine horizontal drill hole into the sump. The drill hole (called <br />' NW Sump #1) is approximately 232 feet in length and is cased with six-inch steel pipe fitted with <br />a high pressure knife valve (see the attached drill hole completion). No water was encountered <br />during drilling of the hole until it was only 17 feet from the sealed sump -even with an estimated <br />' 65 feet of water pressure at this location for nearly one year. Flows from the drill hole have been <br />measured to be just over 1900 gpm when the valve was opened for sampling. <br />' 2) The Rollins Sandstone monitoring well LP-1 is located west and up-dip of the western end of <br />the NW panels sealed sump and as such would not be affected by MCC's use of the sump. MCC <br />t had continued attempts to measure water levels in monitoring well LP-1, even though the casing <br />had apparently sheared or was blocked at about 75' below the top of the casing some time in late <br />1995. Please note that the blockage was documented several months prior to completing <br />' longwall mining of the 7NW panel and more than a year prior to pumping large volumes of water <br />into the sealed sump. Numerous shallow failures have been documented over the years in the <br />Lone Pine Gulch area and is the likely cause of the well damage. <br />1 3) All of the holes listed were drilled for coaVgeology exploration only and were subsequently <br />sealed and abandoned. None of the wells were completed nor left open as monitoring wells. <br />1 <br />