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between the Trout Creek Sandstone and the Middle Sandstone. • WATER LEVELS The potentiometric levels, represented by water levels in the two Trout Creek Sandstone wells, recovered to the levels measured in 1986 through 1988. The recovery of the two wells is apparently from reduction in pumping for use since both wells are used for water supply as well as monitoring. The 1991 levels in both the No. 5 Mine Well and the Okie Plaza Well appear to be 25 to 50 feet lower than the levels measured when monitoring was Initiated in 1985 and 1987, respectively. Water level fluctuations of 20 to 40 feet are also observed but no seasonal pattern is evident or expected. It is likely that the Fluctuations are related to pumping for use. Since the base of the E coal seam in the vicinity of No. 5 Mine Well is above the current potentiometric level In this well, it is not likely that the recent fluctuations in potentiometric levels in the Trout Creek Sandstone is related to mine dewatering in the ovedying E and F coal seams. However, in the past when • potentiometric levels in the Trout Creek were higher and mining of the F coal seam occurred further down dip at lower elevations, dewatering of the coal could have reduced potentiometric levels in the Trout Creek Sandstone. This would require an upward flow in response to the gradient created by mine dewatering. Upward flows may have occurred in the vicinity of fault zones such as in the 2 West Main where water quality monitoring of past water inflows to the No. 5 Mine along a fault zone indicated an ion chemistry similar to ground water in the Trout Creek Sandstone. The water levels in the Middle Sandstone show fluctuations which are apparently related to dewatering and subsidence associated with Mines 5 and 6. The declines in the levels in Wells 81-01 and 83-01 between 1988 and 1990 appear to have leveled off since the middle of 1990. Water levels in these two wells and in 2