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<br />2.1.2 WATER-LEVEL CHANGES <br />The water.-level changes for the period of record are <br />presented on figures in Appendix A. Depth to water and water- <br />level elevation are tabulated in this appendix, also. Many wells <br />reflect changes in annual precipitation amounts. Figure 2-1 (page <br />2-17) presents precipitation at Trapper Mine. Table A-1 on page <br />A-39 in Appendix A presents the water-level data for wells GA1, <br />GA2, GB1 and GB2. Water-level changes for well GA1, which is <br />completed in the QR aquifer, are shown on the hydrograph on Figure <br />A-1 of Appendix A. The Q coal seam was mined less than 1000 feet <br />from this well to the east during 1988 and was not mined during <br />1989 and 1990. The Q and R coal seam was mined less than 2300 feet <br />• to the west during 1990. Water levels were rapidly rising in 1984 <br />and had declined to an average rate of three feet per year during <br />1986. These rises are thought to be due to increased recharge from <br />the increased precipitation in 1983 and 1984 (see Figure 2-1). <br />Water levels declined at a higher rate from 1987 through 1990 with <br />the water levels dropping approximately 42 feet in the last three <br />years. The 1990 rate of decline in water level is greater than the <br />previous 3 years. At least some of this decline is thought to be <br />due to a decline in the recharge from the decline in <br />precipitation. Some of the decline is also likely to be caused by <br />. - the adjacent mine dewatering in the D and E pits: <br />.. .Water levels for well GA2 (see. Figure',A-2),.which is. completed <br />• in the KLM aquifer, had responded similarly in most years with a <br />water-level rise each Spring followed by a decline for the <br />2-4 <br />