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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 and <br />' 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 open <br />workings. At that time it showed virtually no response to room-and-pillar mining. In February <br />' 1988 longwall panel 1 was mined to within about 900 feet of this hole. Obviously, longwall <br />mining disrupts the mined zone more than room-and-pillar mining, and the water level in <br />TW2-17M did show a response to mining at that time. The water level decreased 2.6 feet <br />' during the 2001-02 period. This followed a decrease of 39.7 feet in 1998-99, 11.2 feet in <br />1999-2000, and 5.4 feet in 2000-2001. The 1998-99 water year showed a substantial change <br />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 />' All other middle facies holes experienced what is considered normal fluctuations of water level <br />with a gradual decrease in water levels reflective of drier conditions. <br />' The hydrographs of the "lower sandstone facies" are designated by the letter "L" following the <br />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 />The water level in Hole 30-8M increased 6.0 feet. This was the only well that measured an <br />increase in water level. The cause for the rise is unknown but could represent a recovery in <br />the water table since 1997-98's 46 foot decrease. Mining has not advanced into this area to <br />date. <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 Gassified as "aquitards" in that they will <br />yield water but at very slow rates. Mining in the B Seam so far has encountered only small <br />flows of water and the mine is essentially dry. Previously, water leaking out of caved areas <br />was routed to the sumps at the end of gateroads. No underground water has been pumped <br />out of the mine since the January 31, 1996 underground fire. <br />6 <br />