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Well TR-7A measured during 1991 are similar to the levels measured in 1983 and 1984. The slight recovery <br />• from 1984 through 1988 is apparently the result of a shift in the location of mining to an area further up dip. <br />Water level fluctuations since 1983 are greater in Well 81-01 as compared to Wells TR-7A and 83-01 as <br />would be expected since this well is closer to the location of mine dewatering. <br />The water levels in Well 83-02 show a different pattern. The water level decline of about 150 feet from 1987 <br />to mid 1989 in Well 83-02 is determined to be related to mine dewatering as Mine 5 workings approached <br />the location of the well. The more abrupt 200 foot decline in water levels observed near the end of 1989 <br />and beginning of 1990 is thought to be a drawdown response due to subsidence as its location is only a <br />few hundred feet horizontally from an F seam longwall panel which was mined in a similar time frame. The <br />slight recovery in water level which appeared in Well 83-02 during the later part of 1991 may be related to <br />sealing of subsidence fractures. <br />• Wells TR-4 and 83-03 are located at greater distance horizontally from the active operations for Mines 5 and <br />6. Water levels In Well TRH appear to be related to the fluctuations observed on all three of the <br />downgradient Middle Sandstone Wells, 81-01,83-01 and 83-02. The water level decline in TR-4 prior to 1984 <br />and the subsequent recovery up to 1988 closely parallels the [rends observed in Wells 81-01 and 83-01. <br />The decline during the first part of 1991 also parallels the trend in these two wells. However, the rapid <br />decline during the last part of 1989 and the first part of 1990 appears to follow the trend observed in Well <br />83.02 although the magnitude of decline is considerably less. <br />Well 83-03 is the Middle Sandstone monitoring well located furthest (more than 1.5 miles) from active <br />underground operations for Mines 5 and 6. The water levels in Well 83-03 show pattern that requires further <br />explanation given that potentiometric levels at the well are under flowing artesian conditions. The overall <br />trend from 1984 through 1991 suggests a decline in potentiometric levels of about 15 feet. However, the <br />occasional sharp decline followed by rapid recovery which appear in the time plot are likely the result of <br />3 <br />