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• copper, 'von (both total and dissolved), lead, mercury, molybdenum, nitrite, nitrate, nitrate/nitrite, phosphate, selenium, and zinc. Total 'von levels at the Haulroad Spring were significantly higher than the other springs. RESULTS -MONITORING WELLS FOR WATER YEAR 1998 Three groundwater monitoring wells were sampled during the 1999 water year. The wells sampled are designated 17-B, 94-1, and 95-1. Well 17-B is 600' west of the corner of the northwest permit boundary within Carbon Junction Canyon. Well 94-1 is located adjacent to the east edge of the south pit. Well 95-1 is located approximately 850 feet south- southwest of the future pit boundary. Well 17-B is located upgradient of any disturbance related to mining. Well 94-1 is located within the area disturbed by mining, and well 95-1 is located downgradient and outside the proposed mining disturbance. As such, these wells (94-1 and 95-1) would be expected to show any changes resulting from the mining disturbance. Each of the wells was sampled twice during the 1999 water year. Sampling occurred during the first water year quarter (October 19), and third water year quarter (April 14 or 15). Summaries of sampling data from the groundwater wells for the 1999 water year aze contained in Tables 4, 5, and 6. The depth to water in wells 17-B and 95-1 remained relatively consistent during the 1999 • water yeaz. In well 94-1, depth to water has fluctuated in the last three water yeazs. Between the first and third calendar quarters of 1997, the depth to water in 94-1 increased from 22 to 64 feet. Between the first and second calendar quarters of 1998, the water level returned to 22 feet from 64 feet. Between the fourth calendaz quarter of 1998 and the second calendaz quarter of 1999, the water level in we1194-1 again dropped, this time to 76 feet. At this time there does not appeaz to be a definitive explanation for this occurrence. It is interesting to note this fluctuation, as no significant fluctuation in water level in the other monitoring wells has occurred either above or below the mine. Water temperature in the wells fluctuates regulazly with the seasons. Water temperatures are lowest during the winter months and highest during the summer months. Temperature generally fluctuates most in the shallowest well (17-B) and least in the deepest well (95-1). Temperature ranges for the 1999 water year remained within those observed previously for the wells. The pH for all wells changed from slightly basic during the end of water yeaz 1996 to slightly acidic at the beginning of water year 1997. During this water yeaz (1999), the pH of well 17-B remained weakly acidic. No pH measurement was obtained for well 17-B during the second calendar quarter this year. Well 94-1 returned to a more alkaline range and appeazs to be remaining there, while well 95-1 remained alkaline with a pH of 8.5 for this water year. -5-