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parcel, with its headgate on Fish Creek just above the Bond Creek confluence, washed out in <br />1997, and has not been used since. <br />Based on impact projection analysis performed in the Seneca II Mine permit Tab 7, Section <br />VII.A.1.c., total dissolved solids (TDS) increases in the Fish Creek stream flow as a result of <br />surface water discharges from NPDES8 (Seneca) and NPDES4 (PSCM) and will be on the order <br />of an increase of 76 and 74 mg/l for the months of June and July, respectively. This projection <br />equates to TDS concentrations in the Fish Creek streamflow ranging from 497 to 607 mg/1. The <br />significance of these predicted increases in the TDS concentrations in the Fish Creek AVF are <br />negligible. It has been demonstrated in Tab 7, Section VII.B.1.c., that crops grown in the area <br />can tolerate TDS concentrations in excess of 2,000 mg/l. Predicted TDS concentrations of Fish <br />Creek streamflow of only 497 to 607 mg/1 will in no way result in water quality changes that <br />significantly and adversely affect the composition, diversity or productivity of the vegetation <br />dependent on subirrigation and in no way limits the adequacy of the water for flood irrigation. <br />Table 14 provides June and July TDS values at Site SSF11 (upper Fish Creek) and Site SSF13 <br />(lower Fish Creek) from 2003 to 2015. The maximum increase of TDS between the sites in June <br />was 50 mg/1(average = 25 mg/1) compared to a predicted 76 mg/1 increase. The maximum <br />increase of TDS between the sites in July was 70 mg/l (average = 21) compared to a predicted 74 <br />mg/l increase. There were fewer July samples collected over the twelve year period than June <br />samples. This is due to the fact that Fish Creek is monitored in July only if either Sites SSC 10 <br />(lower Cow Camp Creek) or SSB12 (lower Bond Creek) are flowing. Sites SSC10 and SSB12 <br />usually dry up in late summer although the upstream Outfalls 004 and 008 flow continuously. <br />This reduction in flow is due to stream channel infiltration and evapotranspiration along the <br />lower reaches of both Cow Camp and Bond Creeks. Table 14 indicates that the predicted TDS <br />values in June and July of 497 and 607 mg/l were occasionally exceeded at Site SSF13. This is due <br />to the baseline TDS values at Site SSF11 being higher than expected. In any case, the observed <br />TDS increases between the two sites were always less than the predicted values. Also, the highest <br />TDS value at the downstream site, SSF13, on Table 14, 680 mg/l, is still far less than 2,000 mg/1 <br />crop tolerance level indicated above. Therefore, TDS increases on Fish Creek due to the two <br />mines will not cause any negative impact to crops in the area. <br />34 <br />