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temperature fluctuation in Well WR-1 is somewhat greater than expected suggesting the flow to the perched aquifer, although subsurface, is very shallow. Specific Conductivity/Total Dissolved Solids Specific conductivity (Figure 23) and total dissolved solids (Figure 24) values for the three alluvial wells have remained fairly constant over the period of record, except for 1995. While Conductivity and TDS values at sites TR-3 and TR-4 are consistent with values obtained during the baseline studies, these parameters and several others have elevated rapidly and remained elevated at TR-1.5. The source of the elevated values is not readily identifiable. However, a few factors that may be contributing to the elevated levels have been observed. First, The area surrounding TR-1.5 was inundated with water from beaver dam building activity in the early summer. This activity may have enabled the alluvial water to become stagnant and allowed an increase in the concentrations of various constituents due to a longer residence time. The beaver dam was removed and the area had drained by mid- • summer. Second, shortly after the area had drained a telephone cable was buried in the alluvial valley floor immediately upstream of TR-1.5 which may have disturbed the alluvial soils. If the elevated Conductivity and TDS levels are primarily the result of the previously mentioned activities, it is anticipated that the concentrations will return to more historic levels during future monitoring periods. As previously discussed in the surface water section, data taken between October 1990 and August 1992 is believed to be invalid due to instrument errors. Conductivity and TDS values in Well WR-1 have progressed from elevated levels each spring to lower concentrations in the fall for the past several years. This phenomenon is caused by infiltration of snowmelt water leaching various minerals within the unsaturated zone of reclaimed spoil. As the enriched flow is released over the course of the summer, the conductivity values lessen to that of the stagnant saturated zone. In late 1995, the levels of Conductivity and TDS decreased significantly. This phenomenon may be explained by at least two possible scenarios. First, a significant portion of the runoff on West Ridge no longer infiltrates directly into the spoil and becomes enriched prior to being discharged at the • downslope spring due to the construction of the terraces. Instead, water is directed to the West Ridge Pond where subsurface leakage from the pond may 32