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1 <br />rating curve for the channel cross section with flow measurements being taken <br />on a sporadic basis rather than in conjunction with water quality sampling <br />periods. A further discussion of the channel stability is provided in the <br />discussion on TSS. <br />Surfaces Water Quality <br />The general characteristics: temperature (Figure 1), pH (Figure 2) and <br />1 specific conductivity (Figure 2) exhibit the same trends as found during the <br />baseline studies. Temperature follows the seasonal trend established during <br />baseline. However, it is interesting to note that the period of record does <br />~~ appear to suggest a general warming of the creek waters. Trout Creek remained <br />' alkaline throughout the year with slight variations in pH occurring <br />seasonally. Specific conductivity shows the same trend as the baseline <br />studies, as expected. <br />Tot:~l Dissolved Solids (TDS) concentrations in Trout Creek show the <br />expected pattern of increasing levels as stream flow passes the mine area and <br />then begins to improve downstream with the introduction of inflow from <br />undisttrbed areas downstream of the active mine. In reviewing the TDS <br />concentrations shown in Figure 3, the trend noticed during the baseline <br />studies is further demonstrated. Peak TDS levels in Trout Creek occur in <br />early spring prior to the period of peak flow. This is caused by the uptake <br />of dissolved solids during the spring runoff from the portion of the watershed <br />in which the Edna Mine is located. Although TDS concentrations in the mine <br />runoff may be quite high when compared to concentrations occurring above the <br />mine, the discharge of this runoff is small relative to that of Trout Creek so <br />a large increase in the Trout Creek discharge is not observed. As previously <br />noted, sampling was resumed at TR-C in April 1985. The TDS concentrations in <br />Trout Creek along the mine reach the highest levels at this point. This is <br />not unexpected and as mentioned in the baseline study, the cause for the most <br />elevated TDS levels occurring at TR-C are related to the relative positions of <br />' TR-C and TA-D to the active mining area. All values for TDS, except one, are <br />consistent with the baseline samples. The sample taken at TR-C (TDS = 1658 <br />mg/1) in December of 1985 appears to be an anomaly, perhaps the result of a <br />laboratory analytical error as TR-D does not reflect an influx of TDS. <br />_~ <br />