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.~ Well G81 is completed in the sandstone below the I coal (RLM <br />aquifer) and is located at the base of the A pit, where the H and I <br />coal seams are mined. Mining occurred in this area during 1985. The <br />few water level measurements in this well prior to 1981 are erratic. <br />Two of the four levels are much greater than the recent levels while <br />the other two are extremely less (see Table A-1). Figure A-3 shows <br />that water levels are declining at a steady rate during the last three <br />years. This decline could be due to the mining through this unit in <br />the E pit, a vertical leakage upward in the A pit or to a natural <br />water level change. <br />Water levels in well GB2, which is completed in the Third White <br />Sandstone, were very steady until 1982 when a drop in water level of <br />approximately six feet occurred over a two year period. Water levels <br />the last year have been stable. <br />Well GBS monitors the HI aquifer at the base of the A pit. Water <br />levels (see Figure A-5) in this well were steady until 1979 when water <br />levels started to decline. The rate of decline wars rapid during 1982 <br />and 1983 and a gradual water level rise has occurred in 1984 and 1985. <br />The majority of this water level response is thought to be caused by <br />the A pit dewatering. <br />• The GC wells are approximately three miles from the nearest <br />mining in the H and I coal seams. Well GC1 is completed in the HI <br />aquifer and has shown a considerable amount of water level fluctuation <br />which is all thought to be natural. Figure A-Ii shows that water <br />levels have varied over fifteen feet during the period of record for <br />this well. Water levels were declining during most of 1985 in well <br />GC1, but had risen steadily for most of 1983 and 1984. <br />The recent water levels from the Third White Sandstone well (GC2) <br />indicate that water levels have recently declined in the well. The <br />alluvial well, GC3, hydrograph at this site sFiows a significant <br />variation within time, but does not seem to make as consistent of a <br />pattern as water levels in the HI aquifer. The alluvial aquifer is <br />probably influenced by smaller recharge events than the HI aquifer, <br />Figure A-9., A-10, and A-11 present the water level changes in the <br />QR, HI and Second White Sandstone aquifers, respectively, at the GE <br />site. Water levels in all three of these aquifers started to decline <br />toward the end of 1977. Water levels stopped declining in early 1980, <br />early 1979, and mid 1978 in wells GE1, GE2, and GE3, respectively. <br />All three aquifers seem to be starting to gradually recover in 1985. <br />Water level declines were the greatest in the QR aquifer and least in <br />the Second White Sandstone. These large drawdown:> are likely to be <br />• caused by mine dewatering. The timing of the drawdowns fit the <br />dewatering of Pit C from 1977 to early 1979, but they have not <br />2-2 <br />