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standard for sulfate, 250 mg/1, was exceeded with a value of 570 mg/1. <br />Well STC5 has historically exhibited sulfate concentrations higher than <br />the secondary drinking water standard for this parameter. However, <br />bottled water is consumed at Seneca II. <br />Ground Water Quality Summary. TDS values at six out of the sixteen <br />wells sampled the year displayed increasing TDS trends. TDS trends at <br />all other wells were either stable or decreasing. CDPHE agricultural <br />ground water standards for pH, fluoride, iron and selenium were exceeded <br />at certain monitoring wells. In the area surrounding Seneca II, ground <br />water is not being pumped for irrigation or livestock watering purposes, <br />nor has the CDPHE classified any aquifer in this region for any use. <br />The above discussion is provided only to serve as a comparative basis to <br />judge ground water quality. Domestic wells that provide drinking water <br />for local residents are not from aquifers impacted by mining. <br />Surface Water <br /> <br />Table 7 lists pertinent information on all NPDES, stream, and spring <br />monitoring sites at the Seneca II Mine. A complete description of the <br />surface water monitoring program may be found on Pages 7-336 to 7-355 of <br />the Seneca II PAP, and is summarized on pages 7-349/350. The NPDES <br />permit may be found in Appendix 7-2. All NPDES Discharge Points are <br />monitored monthly for field parameters (flow, temperature, pH, and <br />electrical conductivity) and NPDES lab parameters. Stream Monitoring <br />Sites SSG1, SSG2, SSG3 and SSLG5 are sampled three times a year for <br />field parameters and full-suite water quality. The first sample of the <br />year is collected during the spring runoff (March or April), the second <br />sample is collected after the spring runoff (May or June), and the third <br />sample is collected during base flow conditions (September). Full-suite <br />lab samples collected at all these sites were analyzed using the surface <br />water long list, Table 8. The two stream sites on Fish Creek (Sites <br />SSF11 and 13), and the two on Fish Creek tributaries (Sites SSC10 and <br />SSB12), are monitored monthly from may through July for field parameters <br />and full-suite lab samples. When no flow is observed at both the Cow <br />Camp and Bond Creek sites (Sites 10 and 12), the two Fish Creek sites <br />8