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to 2,491 [0 3,028 mgl 1. The eater remains generally a MgCa-504 type, although the <br />percentage of sulfates have increased approximately 21 percent, and bicarbonates have <br />decreased since the beginning of the truck wash operation. This eater, as one could <br />expect, is of Similar quality to that found at NPDES 002. <br />Surface Nater Site SW-S2-2. This site is the furthest downstream surface eater site in <br />/ the Little Grassy and Grassy Creek drainages prior to exiting the permit area. Therefore, <br />// it is the most significant monitoring site with respect to shooing the cumulative effects <br />of mining in this area. Review of the hydrog ra ph of monthly floe measurements again shoos <br />the lower than normal floes for the past five years. <br />Dater at this site is a MgCa-S04 type. Table 16 (Appendix A) shows that TDS values have <br />generally increased over the period of record. During the last five years, increases in <br />mean TDS are largely attributable to changes in annual precipitation (lower), and slightly <br />higher contributions to TDS loads from truck cash operations associated with the 003 pond. <br />Sorinas. <br />Springs #1, 2 and 3. These springs all exist along the Northeast Diversion Ditch (see <br />Exhibit 7-7 of the Seneca 11 Permit Application Package). Review of Table 18 (Appendix A) <br />shows Spring #1 to historically exhibit a CaMg-HC03SO4 type eater with a relatively low <br />TDS value; however, no floe was observed at this site in the falls of 1987 through 1990. <br />Start ing in 1991, this and all other native springs (i.e., not spoil springs) had their <br />annual sample taken in the spring (usually May) instead of the fall (usually September). <br />No floe was observed for Spring #1 for its annual visit in May, 1991. During 1991, Spring <br />#2 exhibited a CeMg-SO4HC03 Type water and a slight increase in TDS. Due to their <br />location, it is unlikely that either spring is impacted by mining. the last time that <br />floe was noted at Spring #3 was in 1984, <br />Spring #5. This spring is located in the Cou Camp Lreek drainage but, due to its <br />location, is unlikely to be disturbed by mining, No floe was observed at this Site in the <br />falls of 1987 through 1990. A 1985 analysis shoos this eater type with an <br />to be a Mg-S0 <br /> 4 <br />extremely high TDS value of 14,200 mg/l. This high TDS value can be attributed to <br />localized geochemical conditions and not to mining impacts. In May, 1991, this spring's <br />floe was too low to warrant a lab sample (0.2 gpm ); however, an electrical conductivity <br />corrected to 25° C (EC 25°C) measuremenC of 7 <br />800 umholcm was observed <br /> , . <br />18 <br />