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which tabulate depth to water and water-level elevations for each monitoring well over the period • <br />of record. <br />Figure 2-1 presents total annual precipitation at Trapper Mine from 1978 to 1995. <br />Precipitation declined from a high in 1983 to a lo~v in 1988 and has increased from 199] to 1993 <br />with a significant decrease in 1994 followed by the third highest total since 1978 in 1995. Water <br />levels in many wells reflect the natural variation in recharge. These changes may lag the actual <br />events due to the time it takes the water to flow through the respective aquifers to the momtoring <br />wells. Shallow aquifers may even reflect monthly variations in precipitation and recharge. <br />Well GA-1 (QR aquifer) water levels (Figure A-1) were fairly steady in late 1991 and <br />eazly 1992, probably reflecting a balance in natural recharge and dewatering in the adjacent D pit. <br />A slight rise in water level was noted in December, 1992, followed by a large increase of 19.9 ft. <br />between March and June, 1993, remaining at that level for the rest of the year. A decline was • <br />observed in 1994 due primarily to a decrease in annual precipitation. Water levels continued the <br />decline seen in 1994 and remained low in 1995 most likely due to increased dewatering at Pit D. <br />The KLM and QR wells, used as a baseline for precipitation/recharge impacts on undisturbed <br />aquifers (GP-1, GP-2, and GP-6) showed increases in water-level elevation due to the increased <br />precipitation received during 1995. Well GA-2 (KLM aquifer) is adjacent to GA-1 and went dry in <br />1994 and has remained dry throughout 1995. <br />Figure A-2 presents water levels versus time for wells GB-1, GB-5, GF-5 and P-5. The <br />wells aze completed in the KLM, HI, HI backfilled and 2nd White Sandstone aquifers, respectively. <br />Figure A-2 shows steady increases in water levels for GB-1. The sharp decreases are representative <br />of periods after air-lift production. Recovery in this well may still be from the earlier air-lift • <br />2-4 <br />