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<br /> <br />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 5.4 feet <br /> during the 2000-01 period. This followed a decrease of 39.7 feet in 1998-99 and 11.2 feet in <br /> 1999-2000. The 1998-99 water year showed a substantial change probably due to the mining <br /> of LW-12. <br /> Hole 32-7M became dry after longwall mining passed directly beneath this hole. <br />' <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 />' <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 33-8L increased 12.3 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 last year's 31.2 foot decrease. Such recovery could be caused by <br />' natural sealing of cracks allowing water to escape to the nearby underground workings. <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 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 /> <br />i~ 6 <br />