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' No holes were encountered, however, there was wet ground in the area after mining. The area later dried. Longwall panel 3 was mined past this location in April 1990. The next TW2-7U reading after that (6121!90) showed a water level drop of almost 80 feet. The water level in 2-7U eventually showed a drop similar to, though of much smaller magnitude, that shown by TW2-7U. After the drop, both holes exhibited a rising trend. Longwall panel 4 was mined past the location ' in August 1991, with no apparent immediate response from either hole. During this monitoring period both holes were found to have a dry obstruction, 2-7U at 127 feet and TW2-7U at 157 ' feet. Ground movement between the two longwall panels north and south of this location may have caused a kink in these holes. ' Monitor hole 36-2U was mined past in a gateroad during August 1993. There are numerous drill holes at this location and one hole was encountered during mining. The hole encountered ' underground was seeping at the measured rate of 0.25 gallons per minute. It is not known 'rf the hole mined through is one of the monitor holes (36-2U and 36-2L) or one of the exploration holes drilled on this location. During this water year 36-2U showed a decrease of about 6.8 feet ' compared to the average water level of the previous monitoring period. The 35-4 site is located within longwall panel 7 and was mined through in October 1994. Monitor hole 35-4U now shows a dry plug at 232 feet, probably a kinked or sheared casing. It appears unlikely that 35-4U will provide useable data in the future. Water Level at monitor hole 4-20U ' remained practically unchanged. The data collected during this water year continues to demonstrate that there is very limited vertical permeability between the upper and middle monitoring zones. ' The 'siltstone-coal facies' monitoring holes are designated by an 'M' following the hole number. These monitor holes are open through the interval containing the D Seam which is currently being mined. ' Monitor hole TW2-17M was by-passed by mining first in November 1985 but was not intercepted in the workings. It is apparently located in a pillar completely surrounded by open workings. At that time it showed virtually no response to room-and-pillar mining. In February 1988 longwall panel 1 was mined to within about 900 feet of this hole. Obviously, longwall mining disrupts the ' mined zone more than room-and-pillar mining, and the water level in TW2-17M did show a response to mining at that time. The average water level showed a decline of approximately 7 feet during this period. Hole 2-7M is apparently more sensitive to room-and-pillar mining. The water level in this hole had been dropping since mid-1987 when room-and-pillar mining approached to within about 700 ' 9