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lon composition and concentrations in the alluvial wells is very • similar to the ion composition and concentrations of the Middle Creek water below the mine (Station 29) but significantly lower in TDS, SO4 and cations than Foidel Creek above the mine. These results indicate that the water quality of the alluvium at the mine represents a composite of Foidel Creek and Middle Creek similar to the surface water quality in Middle Creek below the confluence. Concentrations of TDS and major ions in the alluvium appear to have stabilized since 1990. The data does not indicate any significant change in the trace metals concentrations although iron and manganese concentrations are extremely variable. The marked increase in manganese concentrations during late 1993 in well 008- AV-2 is likely the result of elevated suspended solids in the samples, as the water levels decreased later in the season. The low water levels had a more dramatic effect on the sample due to the fact that the sediments, which collect in the bottom of the well, were agitated by bailing and showed up in the sample. Spoils Two wells in the Mine 3 spoils were installed in 1985 to monitor water levels and water quality in mine spoils. The location of these spoil wells is provided in Figure 2. One spoil well, 008-SP-4A has remained dry since it was installed. During 1992, this was determined to be the result of a separated casing. As a result of this finding, CYCC installed a replacement spoil monitoring well (008-SP-4B) near the northern embankment of Pond M3S (Site 76). Due to the timing of this installation, CYCC did not provide monitoring information for the replacement well until the 1993 AHR submittal. Water Levels - The plot of the historic water levels in spoil well 008-SP-5A and new well 008-SP-4B is presented on Figure 10. The water level has a similar pattern to that of the alluvial wells; it rises during spring runoff and then declines during the summer and fall. The general trend in water levels in spoil well 008-SP-5A exhibits a relatively slight decline similar to that of overburden well 008-79-06. This trend appears to represent a climatic influence, suggesting that water levels in the spoil have equilibrated and are not fluctuating due to past mine disturbance. Water Quality - The water quality data is summarized in Tables 12 and 13 for the spoil wells. The historic dissolved solids concentrations for the wells are plotted on Figure 11. While highly variable, the dissolved solids concentration does not appear to be increasing but in fact, shows a slight decrease since 1989. The water is a calcium-sulfate type with high bicarbonate and relatively low SAR. The water is higher in dissolved solids than the background bedrock levels and the spoil spring discharges. The data does not indicate any significantly high trace metals concentrations except for relatively high dissolved manganese which appears to have declined dramatically in well 008-SP-5a during • Paqe 4