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1 <br />1 <br /> <br /> <br /> <br /> <br /> <br /> <br />1 <br /> <br />1 <br /> <br />1 <br /> <br />1 <br />1 <br /> <br /> <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 11.2 feet <br />during the 1999-2000 period. This followed a decrease of 39.7 feet the previous water year <br />showing a substantial change probably due to the mining of LW-12. <br />Hole 32-7M showed a decrease of 36.9 feet in water level. As with 32-7U, this drop in water <br />level can be attributed to mine development within 240 feet in the B seam. <br />All other middle facies holes experience what is considered normal seasonal fluctuations of <br />water level. <br />The hydrographs of the "lower sandstone facies" are designated by the letter "L" following the <br />hole number. <br />Hole 32-7L showed a decrease of 61.6 feet in water level. As with 32-7U and 32-7M, this <br />drop in water level can be attributed to mine development within 240 feet in the B seam. <br />Hole 33-8L showed a decrease of 31.2 feet in water level. Mine development in B-Mains had <br />progressed to within about 1100 feet of this hole at the time of the measurement. The upper <br />and middle holes in this group did not experience notable changes. <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 />6 <br />