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2.1 GROUND WATER-LEVEL CHANGES <br />2.1.1 SUMMARY <br />Significant mine acti~~ties during 1994 include the continued expansion of the A, :D and <br />H pit areas, and a decrease in dewatering well pumpage in D pit. <br />Annual precipitation for 1994 was 11.29 inches, down from 18.71 inches in 1993 and <br />below average precipitation. This is the second lowest total occurring during the time period from <br />1978 to 1994 (Figure 2-1). Recharge in this geographic setting is directly related to precipitation. <br />The effects of natural recharge variations on the respective aquifers can be observed in <br />wells located in undisturbed areas away from the influence of mining activities. Wel] GC3 <br />exhibited the alluvial water level response with a small spring and summer increase due to recharge <br />and a fall decline. The net August, 1993 through August, 1994 change was -7.0 ft. This net negative <br />• <br />change (or decline in water-level elevation) is due to the significant reduction in precipitation that . <br />occurred during 1994. The effects on the 3rd White aquifer are observed in wells GC2 and GP9. <br />Both wells show a general decline since 1987 with seasonal variations. The August, 1993 through <br />August, 1994 changes are -0.7 ft. (GC2) and +0.2 ft. (GP9). The HI aquifer (GC1, GP7) is <br />characterized by a flat water level trend with variations over a one foot range. The August, 1993 <br />through August, 1994 changes are -0.60 ft. and +0.06 ft., respectively. The KLM aquifer (GP2, <br />GPS) has showm a declining trend, stabilizing in recent years with variations over a one foot range. <br />The August, 1993 through August, 1994 net changes are -0.2 ft. and -0.5 ft, respectively. The QR <br />aquifer response (GPl) has been an overall decline from 1990 to 1994 with variations over an eleven <br />foot range. The ]994 water-level elevations declined throughout the yeaz. The August, 1993 <br />through August, 1994 net change was -2.9 ft. <br />2-2 <br /> <br />