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<br />' Monitor hole 36-2U was mined past in a gateroad during August 1993. There are numerous drill <br />' holes at this location and one hole was encountered during mining. The hole encountered <br />underground was seeping at the measured rate of 0.25 gallons per minute. It is not known if the <br />hole mined through is one of the monitor holes (36-2U and 36-2L) or one of the exploration holes <br />drilled on this location. During this period the location was mined past with longwall panel seven. <br />Between the first and last readings during this monitoring period 36-2U showed a water level drop <br />of about 43 feet. <br />' Between the last two readings, monitor hole 35-4U showed a drop of about 40 feet as the longwall <br />' face approached. The location was mined through in October 1994. It appears unlikely that 35-4U <br />will provide useable data in the future. Monitor hole 4-20U appears to have stabilized. <br />The data collected during this water year continues to demonstrate that there is very limited vertical <br />permeability between the upper and middle monitoring zones. <br />' The 'siltstone-coal facies' monitoring holes are designated by an 'M' following the hole number. <br />These monitor holes are open through the interval containing the D Seam which is currently being <br />' mined. <br />Monitor hole TW2-17M was by-passed by mining first in November 1985 but was not intercepted <br />in the workings. It is apparently located in a pillar completely surrounded by open workings. At that <br />time it showed virtually no response to room-and-pillar mining. In February 1988 longwall panel <br />t 1 was mined to within about 900 feet of this hole. Obviously, longwall mining disrupts the mined <br />zone more than room-and-pillar mining, and the water level in TW2-17M did show a response to <br />mining at that time. The water level showed a decline of 5.5 feet during this period. <br />' The water level in monitor hole 35-4M had dropped below 300 feet as the longwall face approached <br />t to within about 1500 feet at the last reading. As noted above, this location is within LW-7 and was <br />mined through in October 1994. <br />' Hole 2-7M is apparently more sensitive to room-and-pillar mining. The water level in this hole has <br />been dropping since mid-1987 when room-and-pillar mining approached to within about 700 feet. <br />This area was mined past in June 1988 and the water level has continued to drop, although no <br />monitor holes were intercepted underground. In April 1990, LW3 was mined past this location. The <br />March 1990 water level had dropped beyond our measurement capability and remained so during <br />' this monitoring period. Longwall panel 4 was mined past this location in August 1991. <br />' The hydrographs of the 'lower sandstone facies" are designated by the letter °L' following the hole <br />number. The original hole 2-17L was plugged in early fall 1985 as it was feared the mine would <br />1 9 <br /> <br />