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• monitored at the same frequency as Site 11. The increase in TDS values, <br />from Site 11 to Site 13, was from 700 to 740 mg/1 (6$ increase) in May. <br />It was dry in July through September of this year. <br />On Page 7-247 of the Seneca II Mine Probable Hydrologic Consequences <br />(PHC), predictions were made for the TDS increases to be observed on <br />Fish Creek during the months of June and July due to discharges from the <br />Seneca II Mine. In June, an increase from 421 to 497 mg/1 (18$) is <br />predicted. In July, an increase from 533 to 607 mg/1 (13$) is <br />predicted. However, neither lower Bond Creek nor lower Cow Camp Creek <br />was flowing in June or July this year. As stated in the previous <br />paragraph, only a 6$ increase in TDS was noted between the two sites in <br />May. It appears that the Seneca II Mine has little impact on Fish <br />Creek. Water discharged from the mine is lost to stock ponds, <br />evapotranspiration, and the alluvium as it flows through Twentymile <br />Park. Dissolved solids from mine discharges are diluted during the <br />• snowmelt runoff in March and April (prior to the irrigation season) by <br />high stream flows with relatively low TDS concentrations. The natural <br />conditions in Twentymile Park appear to have a much greater impact on <br />the water quality of Fish Creek. <br />Little Grassy Creek Drainage. Two monitoring sites lie within the <br />Little Grassy Creek drainage: Site 5, located in the southwest portion <br />of the permit area and NPDES Discharge Point 002, also known as the <br />Wadge Impoundment. <br />- Surface Water Site SW-S2-5 (SSLGS). Site 5 drains the upper reaches <br />of Little Grassy Creek which are undisturbed by mining. A comparison of <br />its hydrograph to that of NPDES 002 indicates that Site 5 is a <br />relatively minor contributor to the flow in this basin. <br />- NPDES Discharge Point 002 (NPDES2). Hydrographs are presented in <br />Appendix D. The hydrographs consist of two pages, the first is for data <br />• this year, and the second shows all historical data. The following <br />table lists the average flow values for each water year. <br />IS <br />