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The middle "siltstone-coal facies" monitoring holes are designated by an "M" following the <br />hole number. These monitor holes are open through the interval containing the D Seam <br />and B Seam. <br />Monitor hole TW2-17M was by-passed by mining first in November 1985 but was not <br />intercepted in the workings. It is apparently located in a pillar completely surrounded by <br />open workings. At that time it showed virtually no response to room-and-pillar mining. In <br />February 1988 longwall panel 1 was mined to within about 900 feet of this hole. <br />Obviously, longwall mining disrupts the mined zone more than room-and-pillar mining, and <br />the water level in TW2-17M did show a response to mining at that time. The water level <br />has steadily decreased since 1988 with a decrease of 7.8 feet during the 2003-04 period. <br />This followed a decrease of 39.7 feet in 1998-99, 11.2 feet in 1999-2000, 5.4 feet in 2000- <br />2001, 2.6 feet in 2001-2002, and 9.0 feet in 2002-2003. The 1998-99 water year showed <br />a substantial change probably due to the mining of LW-12. <br />Hole 32-7M became dry after longwall mining passed directly beneath this hole in 2001. <br />The water level in Hole 30-8M decreased 37.5 feet. The cause of this decrease is most <br />likely the advancement of mining development nearer to the well. This well is scheduled <br />to be mined through in 2006. <br />All other middle facies holes experienced what is considered normal fluctuations of water <br />level. <br />The hydrographs of the "lower sandstone facies" are designated by the letter "L" following <br />the hole number. <br />Hole 32-7L was mined through by the longwall in early 2001. Prior to being mined through <br />the hole was plugged to above the coal seam with Baroid Holeplug. <br />All other lower facies holes experience what is considered normal seasonal fluctuations of <br />water level. <br />From the baseline data, all three zones should be classified as "aquitards" in that they will <br />yield water but at very slow rates. Mining in the B Seam so far has encountered only <br />small flows of water and the mine is essentially dry. Typical flows are in the order of 6 to 8 <br />gpm with occasional short term increases when localized perched water tables are <br />encountered. Previously, water leaking out of caved areas was routed to the sumps at the <br />end of gateroads. No underground water has been pumped out of the mine since the <br />January 31, 1996 underground fire. <br />6 <br />