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feet. This area was mined past in June 1988 and the water level had continued to drop, although no monitor holes were intercepted underground. In April 1990, LW3 was mined past this location. The water level had dropped beyond our measurement capability from March 1990 through July 1994, however, the new equipment shows a dry blockage at 437 feet. Longwall panel 4 was mined past this location in August 1991. ' The hydrographs of the 'lower sandstone facies' are designated by the letter 'L' following the hole ' number. The original hole 2-17L was plugged in early fall 1985 as it was feared the mine would intercept it. As it turned out, the hole was never encountered in the workings. As required by DMG, a new hole was drilled and completed in the °lower sandstone facies'. From the time the ' new hole was completed, the water levels in this hole have fallen. During May 1986, mining in gate road 2nd East intercepted an exploration hole, (21012-9) that had been drilled in 1978. This ' hole had been plugged with heavy mud but leaked from both the mine roof and floor when the hole was intercepted. Water flow from the hole in the roof was about 3 gpm (gallons per minute) and was plugged with a packer. The flow from the hole in the floor was on the order of 1 gpm and ' was plugged by pumping an expanding grout into the hole. This exploration hole is located about 1500 feet from 2-17L and the leak in the floor may have reduced the piezometric pressure in the "lower sandstone facies' at 2-17L During March of 1987, another exploration hole (21012-10) ' was intercepted by mining in gate road 3rd East. This hole also leaked at about the same rate from roof and floor. The hole in the roof was plugged with expanding foam grout. The hole in the ' floor was plugged with Portland Cement pumped down a one inch line to about 100 feet. The leaks in both 21012-9 and 21012-10 are probably responsible for the fall in water levels detected at 2-17L during the fourth water year. Mining of LW-1 approached to within 500 feet of this hole ' in February 1988. During this monitoring period, the water level ranged from 406.0 to 412.0 feet. Perhaps the combination of leaking exploration holes and floor cracking as coal was removed by ' the longwall have reduced the piezometric pressure enough to drop the water level to this point. Monitor holes 2-7L and TW2-7L are on the same location and apparently also responded to the t two leaking exploration hoes. Longwall panel 3 was mined past this location in April 1990 and the water level had dropped below 300 feet. Longwall panel 4 was mined past this location in ' August 1991. Well 2-7L has a dry blockage at 650 teet while TW2-7L has a dry blockage at 660 feet. During this monitoring period, the average water level in monitor hole 36-2L has remained unchanged at a depth of 188 feet. Monitor hole 35-4L was found to have a dry obstruction at 438 feet. The 35-4 location was mined through in October 1994. The hole is venting air and has ' been capped. 10 ' 1