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in the third quarter of 1996 due to the D pit mining. The backfill aquifer in this area is <br />monitored in GD-3 and GF-11 and indicates similar water when compared with GD-2 and <br />GF-6. Therefore, a backfill well in this area is not deemed necessary. <br />2.1 GROUND WATER-LEVEL CHANGES <br />2.1.1 SUMMARY <br />Significant mine activities during 1996 included the continued expansion of the A, <br />D and H pit areas. Pit D dewatering was slightly higher in 1996 than in 1995, while the D <br />pit dewatering wells volume of pumping increased greater than three times. Dewatering in <br />the A and H pits was nearly twice and four times their 1995 volumes. <br />Annual precipitation for 1996 was 17.75 inches, six percent larger than the site's <br />average precipitation. This is two inches less than the 1995 value (Figure 2-1). Recharge • <br />in this geographic setting is directly related to precipitation. <br />The effects of natural recharge variations on the respective aquifers can be <br />observed in wells located in undisturbed areas away from the influence of mining activities. <br />Well GC-3 exhibited the alluvial water level response with a smaller increase in 1996 due <br />to recharge than observed in 1995 and a larger fall decline. The net August, 1995 through <br />August, 1996 change was -3.1 ft. This decline is due to the smaller precipitation that <br />occurred during 1996. The effects on the 3rd White aquifer are observed in wells GC-2 and <br />GP-9. These wells show awater-level rise in late 1995 and 1996, indicating some lag from <br />seasonal precipitation variations. The HI aquifer (GC-f, GP-7) is characterized by a flat <br />water level trend with variations over a one to two foot range. The August, 1995 through <br />.~ , <br />2-2 <br />