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for 1992 only, chile the second shows historical data from July, 1982 to September, 1992. The mean weekly flows for the past several years were: 1992YY (Pater Yeer) = 0.131 cfs 1991YY = 0.189 tfs 1990YY = 0.135 cfs 1989YY = 0.214 tfs 1988YY = 0.180 cfs 1987YY = 0.110 cfs 1986YY = 0.294 cfs 1985CY (Calendar Yesr) = 0.357 cfs 1984CT = 0.447 cfs 1983CY = 0.154 cfs (reservoir did not completely fill until March 7, 1983) Review of hydrographs end the above table shows that floe the past six years has been loner than previously measured. This is largely due to relatively lower snowmelt runoff • during this period. Also affecting flow from the 004 pond is the reduced diameter of the discharge culvert modified on May 29, 1987 (36 inches to b inches). Review of Table 15 (Appendix A) shows the water et this site to be a NgCa-S04 type. TDS has consistently increased since 1982 primarily due to a concurrent increase in upgradient mined area and ground water resaturation in the spoils. Also responsible for the increase in TDS in 1987 through 1992 is the decreased spring snowmelt runoff for this period as compered to 1984 through 1986. Reduced runoff and subsequent evaporation during the summer tends to concentrate dissolved solids, resulting in increased TDS over time. Surface Water Site sY-S2-6. This site monitors Cow Camp Creek less than 1/4 mile downstream of the NPDES 004 discharge and an adjacent diversion ditch. Review of a hydrogreph consisting of all data from May, 1981 to September, 1992 shoos that spring runoff has been lower than normal the last six years. Peak floes at this site have been reduced further by the reduction of the discharge culvert diameter in 1987 at the NPDES 004 site discussed earlier. • Review of Table 16 (Appendix A) shows that Site 6 displays a MgCa-504 type cater. TDS values have increased every year (excepting 1991) as a result of the TDS increases noticed 13