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Page 7 <br />over other periods which is attributed to dilution of the groundwater by <br />surface runoff from sno•~rmelt. Samples taken early in the snowmelt period <br />will sometimes show higher than average TDS concentrations caused by the <br />infiltration from snowmelt 'flushing" Qroundwater into the drainages. <br />The streams and alluvial wells do not show either an increase or <br />decrease in TDS concentration attributable to mining, and other than the <br />exceptions noted above, the levels are within the range of values found <br />during baseline. The permit application predicted an essentially unchanged <br />influence on Trout Creek from mining until the Moffat Area is mined and the <br />results during 1984 are consistent with this prediction. <br />Total Suspended Solids <br />The Total Suspend e3 Solids (TSS) concentrations in both Trout Cree'r, <br />and Oak Creek showed dramatic, expected increases during the sno~.nnelt <br />runoff period. Trout Creek TSS levels caent from the 10-20 mg/1 range <br />during the baseflow period to 1800-4500 mg/1 for the samples taken during <br />the runoff from snowmelt. There is no indication that the mine had any <br />negative effect on these concentrations since they decrease along the mine <br />and the NPDF.S samples show that the effluent from the ponds was within the <br />allowable concentrations throughout the year. The most likely reason for <br />these unusually high concentrations is the erosion and disturbance caused <br />by ±he channel changes noted previously in the discussion of the monitoring <br />locations. It is possible that the 1985 TSS concentrations may again be <br />unusually high even if the flows are not as the channel adjustments begun <br />in 1984 continue. <br />