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Figures 11 through 13. The water levels in the adjacent streams show the typical seasonal pattern of relatively rapid increase and decline due to spring runoff. In addition they show the general decline in water levels due to the relatively low runoff since 1987. While the seasonal variation in the water levels in the Foidel Creek alluvium is readily apparent, no impact from the mining is evident. The average water level in the 001-5-5, AV-1 and 008-AV-2 wells, adjusted for differences in spring runoff, has not changed since monitoring began in 1979. The alluvial well immediately downgradient from Pond A (Well 009-S-10) shows a slight water level decline compared with previous years sue to much lower discharge volumes. The water level data for the Fish Creek alluvial wells do not show any impact from the reclaimed Mine 2 Area. Water Quality The water quality data area summarized in Tables 12 through 17 for the Foidel Creek alluvial wells and Tables 18 through 23 for the Fish Creek alluvial wells. The historic field conductivities for the Foidel Creek wells are plotted on Figure 14, and for the Fish Creek wells on Figure 15. Seasonal variation in conductivity is apparent in the wells. This is probably due to the flushing effect of relatively low dissolved solids surface water which recharges the alluvial aquifers during spring runoff.. • There was a small increase in the average salt content of the Foidel Creek alluvial groundwater starting in the 1987 water year and continuing through the 1993 water year. This is probably due to the relatively low runoff which has persisted since 1987. The water quality in the Foidel Creek alluvial wells show a downstream increase in total dissolved solids and conductivity and change from a sodium-bicarbonate type to a mixed calcium-sodium-bicarbonate- sulfate type. The change is apparent in the reach between the 009- 5-10 well and the 001-5-5 well. This is primarily attributable to recharge of alluvium by Foidel Creek water which receives sediment pond discharges, containing elevated concentrations of dissolved solids, calcium and sulfate, in the reach of Foidel Creek above the 001-5-5 well. The sediment pond water is largely derived from spoil runoff and spoil springs. The spoil springs, in particular, are characterized by high sulfate, calcium and dissolved solids concentrations. There is no indication of any significant increase in trace metals in the alluvial groundwater during 1993. The water quality data for the Fish Creek alluvial wells upstream and downstream of Mine 2 do not indicate any impacts (Figure 15). The 006-AW-2 well, downgradient from the discharge point, does show a higher conductivity during the baseflow period than in previous years related to underground mine discharge. The data does not indicate any significant changes in the trace metals concentrations. The iron and manganese levels in the wells, •