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-2- Water level declines in Wells TR-4, TR-7A and 81-01 from 1981-1984 were attributable to mining activity and advancement of the No. 5 mine. Based upon Figure 13, the hydraulic gradient is approximately 350 feet per mile in the southeast and is 150 feet per mile in the west. The difference in hydraulic gradient between these areas is either due to lower hydraulic conductivities in the southeast or mining activity has artificially induced a steeper gradient towards the mine. Except for Well TR-7 which had a datum error of several hundred feet on the 1983 Potentiometric Map, there has been little change in hydraulic gradient in 1984. Twenty-Mile Sandstone The Twenty-Mile Sandstone lies approximately 230 feet above the Middle Sandstone and approximately 300 feet below the "P" coal seam, No. 9 mine. Empire Energy presently has three monitoring wells, 259, No. 9, and 84-01 completed in the Twenty-Mile Sandstone. Well 259 is the only well with water level data. Figure 9 indicates that there has been relatively little change in water levels in the Twenty-Mile Sandstone from mid 1981-1985. Well 84-01, completed in December 1984 is suppose to monitor water levels in the Twenty-Mile Sandstone on a monthly basis. Up to the end of the second quarter 1984, no water level data has been submitted to the Division. White Sandstone The White Sandstone is the uppermost principal aquifer in this region and lies approximately 130 feet above the "P" coal seam. Wells, 81-03a, 81-04A and 81-19, (Figures 10, 11, and 12 respectively), are completed in the White Sandstone. Figure 10 indicates there was a sharp decline, approximately 35 feet, in water levels in well 81-03A from mid 1982 to the beginning of 1983. Since that time water levels have been steadily recovering up to the end of the third quarter 1984 when water levels have started to decline. Early water level declines from mid 1982 to 1983 suggest that No. 9 Mine activity may have impacted the White Sandstone aquifer. In recent years mining activity and advancement has either slowed down significantly or ceased completely, and has caused water levels to either stabilize or rise in well 81-03A. We11s 81-04A and 81-19 have been less impacted by the No. 9 Mine since they are further away from the No. 9 Mine than well 81-03A. Water levels in well 81-04A have not fluctuated more than 10 feet over the entire monitoring period. Except fora period from mid 1982 to the first quarter well 81-19 have not changed more than 10 feet. During 1982 to the first quarter 1983 water levels dropped app was the same period that water levels declined 35 feet Increased mine discharge and advancement may have been local ground water decline. 1983, water levels in the period from mid proximately 25 feet. It in well 81-04A. responsible for this Potentiometric Surface Map, Figure 14, indicates that there has been a change in the direction of ground water flow from 1983 to 1984. In 1983 the hydraulic gradient was to the north. In 1984 the hydraulic gradient was in r more of:saenorthbesterly direction.