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I ~ All iron excursions were the result of high suspended solids. Both sites are upstream of Seneca's discharges. There was one copper value (from NPDES2) that had an elevated detection limit higher than the chronic standard. The cause of this elevated detection limit was a decision by the laboratory to dilute the sample prior to analyses in order to reduce the effects of interferences (such as high salinity). Likewise, there was one selenium value (from NPDES2) that had an elevated detection limit higher than the chronic standard. One site, NPDES2, experienced a mercury value of 0.3 ug/1. Lab error is suspected, since the value before the excursion, and the three samples after the excursion, were all below the detection limit, 0.2 ug/1. The standard for mercury is 0.01 ug/1. Only two samples experienced exceedances of the sulfide standard (0.002 mg/1 un-ionized). These samples are from streams above Seneca's • discharges. However, any dissolved sulfides present in surface water should eventually oxidize to sulfates. NPDES Effluent Criteria (Permit No, CO-0000221). Three excursions of NPDES effluent criteria occurred this year. NPDES4 experienced an excursion of the total recoverable iron limit, 1.0 mg/1, on April 7 with a value of 1.47 mg/1. The site was receiving snowmelt runoff at the time, and the excursion was a result of relatively high suspended solids, 26 mg/1. This site was in compliance for iron for all months after the excursion. Both NPDES4 and NPDESS failed chronic WET tests performed in July. Accelerated WET tests for both sites passed the limits, indicating that the toxic episode was transitory (or may have never existed in the first place, i.e. lab error). Surface Water Summary. Water discharged from the Seneca II Mine is not • used directly for irrigation. Indirectly, although, water discharged from the mine is significantly diluted by water from either Fish Creek 23