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I. Surface Water A. Trout Creek All the proposed mining will take place in Trout Creek drainage. Trout Creek is a perennial stream. From the baseline study it was determined that peak flows occur in early to mid June and flows are well in excess of 100 cfs from May through July. Low flows of approximately 10 cfs occur in late fall, just before winter freeze-up, and in early spring. Three sites were utilized for the baseline flow study and two of these sites are part of the ongoing monitoring program. TR-a is at the upstream edge of the mine and TR-b is downstream of the permit boundary. The quantity data submitted in the 1982 and 1983 hydrologic monitoring reports is similar to that of the baseline with higher flows from above normal precipitation. The gauge rating curves were recalibrated in 1983. The recalibration showed that while low flow data was fairly accurate, high flow data could be questionable. This is due in part to the changes the channel is going through at the location of TR-b. These changes have caused interference in the communication between the stilling basin and stream. It may be necessary to change the location of TR-b if it does not appear that the channel is stabilizing. There were 4 water quality sampling points established along Trout Creek for the baseline study. They were placed upstream of mining (TRA), adjacent to old mine spoils (TRB), adjacent to the Moffat Area (TRC) and downstream of mining (TRD). In the baseline study the 2 sites adjacent to the permit area had the poorest water quality, with TRC the worst while the quality improved downstream from mining at the site TRD due to dilution. The poor water quality at sites TRB and TRC is due to drainage from unreclaimed mine spoils. Numerous springs occur at the toe of the spoils slope and drain directly into Trout Creek. The water upstream in Trout Creek is of a calcium bicarbonate type while immediately downstream from the mine the chemical character is of a calcium sulfate type. The water quality criteria established by EPA in 1972 were used for the baseline study. The most often exceeded criteria at all the stations were iron, zinc, and manganese, however these values were exceeded less than 40% of the time. Nickel and silver also periodically exceeded the criteria. Several values (nitrate, sulfate, sodium, calcium and magnesium) increased substantially from the upstream site to the downstream site, but are still within the recommended criteria. The worst TDS levels during the baseline study occurred at the stations adjacent to the mine area with some improvement at the downstream station. Maximum value at TRA was 535 mg/1, TRB was 768 mg/1, TRC was 629 mg/1 and TRD was 565 mg/1. The numerous springs that drain directly into the creek in the vicinity of sites TRB and TRC have been sampled at TDS levels as high as approximately 3,000 mg/l. From this data it is apparent that Trout Creek has a tremendous dilution effect on spoils water quality.