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undisturbed areas downstream of the active mine. In reviewing the TDS concentrations shown in Figure 3, the trend noticed during Che baseline studies is further demonstrated. Peak TDS levels in Trout Creek occur in early spring prior to the period of peak flow. This is caused by the uptake of dissolved solids during the spring runoff from the portion of the watershed in which the Edna Mine is located. Although TDS concentrations in the mine runoff may be quite high when compared to concentrations occurring above the mine, the discharge of this runoff is small relative to that of Trout Creek so a large increase in the Trout Creek discharge is not observed. As previously noted, sampling resumed at TR-C in April 1985. The TDS concentrations in Trout Creek along the mine reach the highest levels at this point. This is not unexpected, for, as mentioned in the baseline study, the cause for the higher TDS levels occurring at TR-C i9 related t0 the relative positions of TR- C and TR-D to the active mining area. The dilution of TDS concentrations in the stream flow since 1988 has not been as pronounced as in previous years. The reason for this is not clearly understood, for active mining directly above TR-C did not begin until 1990. it is possible that the trend prior to 1990, therefore, was reflecting an increase in farming activities along the western side of Trout Creek in the vicinity of the Edna Mine. All values for TDS, except one, are consistent with the baseline samples. The sample taken at TR-C (TDS 1658 mg/1) in December of 1985 appears to be an anomaly, perhaps the result of a laboratory analytical error as TR-D does not reflect an influx of TDS. Total Suspended Solids (TSS) show a general continuing decrease in concentration from 1984 (Figure 3). As previously discussed, the flooding which occurred in 1989 caused some rather dramatic changes to the stream channel. The TSS values obtained since 1988 suggest that the reaches along Trout Creek that were affected during the high flows of 1989 have again stabilized with TSS values being consistent with values obtained during ' baseline sampling. The samples taken in late May of 1988 suggest some bank caving may still have been occurring during peak flow periods in the spring. This is indicated by a substantial increase of TSS values occurring at TR-C and TR-D when compared to the other upstream sampling stations. Calcium (Figure 4) is the dominant cation in Trout Creek with magnesium (Figure 9) and sodium (Figure 6) occurring in lesser concentrations. While the relative proportions of these parameters change slightly between the