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conductivity are higher in the fall and spring and lower in the winter. Higher • temperatures are expected with the onset of warmer weather and generally warmer cechazge water and warmer temperatures in the rock strata which conveys the flow in these near surface springs. With a decrease in flow and accompanying decrease in solvent volume, EC readings are expected to increase in the late spring through winter quarters. As the springs are recharged by snow melt, the EC readings show a decrease. Many trace elements were consistently found to be below the detectable limits for both springs for the 1996 water year. These same trace elements have historically been found to be below detectable limits. They are aluminum, arsenic, cadmium, copper, iron, mercury, nitrite, nitrate, nitrate/nitrite, lead, phosphate, and selenium. The other trace elements tested at a detectable level are for the most part consistent throughout the water year, with some characteristic variations between the two springs. RESULTS -MONITORING WELLS FOR 1996 WATER YEAR Three wells were sampled during the 1996 sampling period. The wells sampled were designated 10-B, 17-B, and 94-1. Well 10-B is located approximately 400' east of the northeast rim of the south pit. Well 17-B is 600' west of the comer of the northwest permit boundary within Carbon Junction Canyon. Well 94-1 is located adjacent to the east edge of the south pit. Well 17-B is located upgradient of any disturbance related to • mining. Wells 10-B and 94-1 are located within the area disturbed by mining. As such they would be expected to show any changes resulting from the mining disturbance. Depth to water for the wells has remained consistent in the 1996 water year. The pH is slightly basic for all three wells. The temperature of the wells is slightly higher in the fourth, second, and third quarters, and lower during the winter quarter. This temperature regime could be explained by recharge from snow melt during the winter months. The shallowest well, 17-B, shows the greatest fluctuation in water temperature during the year, lending further credence to the recharge hypothesis. Well 17-B is also characteristically lower in calcium, bicarbonate, electrical conductivity, magnesium, ammonia, sulfate, and total dissolved solids than are wells 10-B and 94-1. This appears to be characteristic of the groundwater at this location and not related to mining activity, as wells 10-B and 94-1 have not illustrated rises in these parameters during the sampling record. Many of the trace elements found to be below the detection limits for the springs sampled were also found to be below detection limits for the wells sampled. These trace elements are arsenic, cadmium, iron, mercury, nitrite, nitrate, nitrate/nitrite, and selenium. Other trace elements found at detectable limits are consistent within each well at levels that do not indicate high or low fluctuations of these elements. Overall, elements that are detectable and those that are not have been consistent throughout the • well sampling program at the Carbon Junction Mine. 3