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• facilities began. Water is siphoned from the Wadge Is¢toundment (NPDES 002) into a holding <br />pond. Overflow from the holding pond is dlverted into the shop ditch vhicR flows into <br />NPDES 003. Water is pumped from tRe holdlnq pond to the wasR rack, drains into a settling <br />pond, and then into the same shop ditch. This operation has Increased the flow at NPDES <br />003 while decreasing the flow at NPDES 002. Tvo other events that affected the long-term <br />hydtograph include the diversion away from NPDES 003 of runoff from a fly ash pit operated <br />Dy Colorado-Ute Electric Association in October, 1950, and the diversion away from NPDES <br />003 of rvnoff contained in the Northwest Diversion Ditch (see the Seneca II Permit <br />Application, Exhibit 7-7, Surface Water Frydrology Hap and also the 1982 Seneca II Ali) in <br />April, 1952. Finally, discharge wlumes at the 003 site nave Deen affected by the <br />reduction in diameter of the discharge culvert (36 inches to 6 inches) which occurred on <br />July 19, 1988. No con¢+arison of thIS years' flows to prior years is presented since the <br />operation of the truck wash system tends to greatly influence the floe conditions at Pond <br />003. Aevlev of the TD9 plot indi cater a slightly increasing trend. <br />Surface Water Site 9W-92-2 (SSG2). This site is the furthest downstream surface water <br />site In the Little Grassy and Gzasay Creek Qrainages prior to exiting the permit area. <br />• Therefore, it is the most significant monitoring site with respect to showing the <br />cumulative effects o£ mining in this area. Review of the hydrograph of monthly flow <br />measurements again shows the highest peak floes since 1993 and 1986. Review of the TDS <br />plot indicates an increasing trend. <br />Springs. <br />Spring data may be found after the surface eater data presented in Appendix E. Spring <br />(native) data provided are a eater quality report for the year, historlc floe measurement, <br />and a historic listing of percent millequivalents and TDS. Spoil spring data provided are <br />eater quality data for the year, historic floe measurements, and a LOWESS plot of field <br />conductivities (corrected to 25° C slnee 10/1/39). In addition, a floe Rydroqraph and TDS <br />LOWE39 plot are provided for Spoil Spring M1. In Appendix E, springs (native) have a SSPG <br />prefix, while spoil springs have a SSSPO prefix. <br />6pringe M1, 2 and 3. These springs all exist close to the north permit boundary. Spring <br />M1 vas not flowing during its June, 1995 visit. During 1995, Spring M2 exRibited a TDS <br />• valve of 1940 mq/1. Due to their loeati on, St is unlikely that either spring is Impacted <br />by mining. TRe last time that flow was noted at Spring M3 vas In 1954. <br />13 <br />