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[J ' Monitor holes 2-7U and TW2-7U are located on the same Location. Although the water levels in the two holes have been comparable, fluctuations and trends in each hole have in the past been quite dissimilar. A longwall gateroad (4th East) was developed past this location in June 1988. No holes were encountered, however, there was wet ground in the area after mining. The area has since dried. Longwall panel 3 was mined past this location in April 1990. The next TW2-7U reading ' after that (6/21/90) showed a water level drop of almost 80 feet. The water level in 2-7U has, during this reporting period, shown a drop similar to, though of much smaller magnitude, that shown by ' TW2-7U during the previous period. After the drop, both holes exhibited a rising Vend. Longwall panel 4 was mined past the location in August 1991, with no apparent immediate response from either hole. However, during this monitoring period both holes showed a drop in water level, again, ' with the drop in TW2-7U a much greater magnitude than that in 2-7U. The fact that these two holes completed in the same zone within a short distance of each other respond so differently further indicates the isolated nature of water bearing sVata within the same zone. There are three other monitor holes at this same location, one in the middle zone and two in the lower. ' Monitor hole 36-2U showed a water level drop of about 6 feet between the June 1992 and August 1992 readings. By August 1992 gateroad development mining had progressed to within about 1000 feet of this hole. ,S '~ .r` ~~/a - f'."-- /'~'/ /• ' Monitor hole 35-4U showed a 2-Toot drop in the August 1992 reading. Gateroad development mining passed within about 500 feet of this hole in early 1992. Monitor hole 4-20U continues to display a slow declining trend."y'~I`,,, '~ ~~~ I'~ •: i ; ~ , ;, 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 water level has continue to show a slow decline during this period. ' ~~ l ~ Spa, ~;- :.- ~ ~q~=! ya > i~R ,', ~... ~ ' Z y,~ - o/.,, Mining activity approached to w`ithin~about 500 feet of 35-4M in early 1992. The first three readings of this monitoring period showed a stable water level and then the last reading showed a drop of 9 -~ 'I ~~