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02 although the magnitude of decline is considerably less. Well 83-03 is the Middle <br />Sandstone monitoring well located furthest (more than 1.5 miles) from active <br />underground operations for Mines 5 and 6. The overall trend from 1984 through 1994 <br />suggests a similar trend to the other Middle Sandstone wells. The long term decline <br />could be a pressure response due to the overall drop in potentiometric levels in the <br />Middle Sandstone in the vicinity of Mines 5 and 6. Overall, the water levels in the <br />Middle Sandstone wells has either recovered or stabilized in 1994. <br />Monitoring results through year 1994 (Fig. 10) still show no apparent change in the <br />water levels in the Twentymile Sandstone that could be attributable to mining <br />activities. Water level plots indicate essentially no change. <br />Based upon the 1994 piezometric map (Figure 11), the groundwater gradient in the <br />Middle Sandstone ranges from 130 feet per mile to the southwest to 50 feet per mile <br />to the west-southwest. The drop in potentiometric levels in the Middle Sandstone unit <br />above the subsided longwall mine panels in the F and E coal seams has created a <br />potentiometric gradient to the south in the vicinity of the longwall panels. A piezometric <br />contour map of the Twentymile Sandstone is presented in Figure 12. The map <br />indicates that the gradient is approximately 220 feet per mile to the northwest and <br />shows essentially no change from 1991. <br />C-01.044 1994AHR Page 4 <br />