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Grassy Creek but water quality in Grassy Creek generally meets the standazds established for Fish Creek. Water quality in Fish Creek shows no significant impact associated with mining. Data collected at site SW-S2-13, downstream from mining activities meets receiving stream standazds. Pond outfalls (NPDES outfalls 002, 003, 004, and 008) are monitored according to the requirements of the Seneca II Mine NPDES permit (see section B of this document "Monitoring"). With the exception of the exceedence of total suspended solids (TSS) in September, 2001 at the Northwest Impoundment (003) and a WET test failure at dischazge point 008 in August, 1998, no parameters have exceeded NPDES limitations in the previous permit term. One exceedance of NPDES effluent criteria occurred in 2001 at the The Northwest Impoundment (003). NPDES 003 experienced an excursion of the 30 day average total suspended solids (TSS) limit of 35 mgll with a value of 38 mgll measured from a sample collected September 12, 2001. However, a retest of that sample resulted in a TSS value of only 8 mg/I. The TSS value on a sample collected on October 16, 2001 was back down to only 6 mg/1. In 1998 a WET test failure for dischazge point 008 occurred on samples collected August 5-10. Accelerated test were performed on split samples by two sepazate labs on samples collected August 26-31, 1998 and September 9-14, 1998. All subsequent tests performed passed, therefore, the incident is now closed. Increased Total Dissolved Solids Loadine An increase in_salinity, as.represented by TDS concentrations, is the major surface water impact caused by the Seneca II Mine. The disturbance of sedimentary rocks during the mining and reclamation process exposes more surface azea for the solution of minerals and increases the amount of solute available for transport to surface streams. An increase in TDS concentration between upstream and downstream stations on Grassy Creek has been observed at the Seneca II Mine. This effect has been appazent throughout the monitoring period, 1981 to 2002. In 1981 an average TDS concentration of 582 mg/1 was observed at the upstream site and an average TDS concentration of 1,600 mg/1 was observed at the downstream location. In 2002, a TDS concentration of 855 mg/I was observed at the upstream location and a concentration of 2,493 mg/1 was observed at the downstream site. An increase of 893 mgll between 1981 and 2002 at the downstream site is likely attributable to mining. An increase in TDS from 600 mg/] prior to mining in the Cow Camp Creek Drainage to approximately 3,941 mg11 has been observed in monitoring data 25