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mandatory) drinking water standards developed for ground water by the <br />CDOH. No human health standards were exceeded. The CDOH secondary <br />standard for sulfate, 250 mg/1, was exceeded twice with values of 450 <br />and 540 mg/1. Well STC5 has historically exhibited sulfate <br />concentrations higher than the secondary drinking water standard for <br />this parameter. However, bottled water is consumed at Seneca II. <br />Ground Water Quality Summary. TDS values at ten out of the nineteen <br />wells sampled the year displayed increasing TDS trends, although two of <br />those wells recently display stable trends. TDS trends at all other <br />wells were either stable or decreasing. CDOH agricultural ground water <br />standards for pH, fluoride, iron, and manganese were exceeded at certain <br />monitoring wells. In the area surrounding Seneca II, ground water is <br />not being pumped for irrigation or livestock watering purposes, nor has <br />the CDOH classified any aquifer in this region for any use. The above <br />discussion is provided only to serve as a comparative basis to judge <br />ground water quality. Domestic wells that provide drinking water for <br />local residents are not from aquifers impacted by mining. <br />Surface Water <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. NPDES <br />Discharge Point 003 is monitored weekly for field parameters (flow, <br />temperature, pH, and electrical Conductivity). Points 002, 004 and 008 <br />are monitored monthly for field parameters. All four NPDES sites are <br />monitored monthly for NPDES parameters. Stream Monitoring Sites SSG1 <br />and SSG2 are monitored for field parameters monthly from March through <br />October. Both of these sites, as well as Sites SSG3 and SSLGS, are <br />sampled three times a year for full-suite water quality. The first <br />sample of the year is collected during the spring runoff (March or <br />April), the second sample is collected after the spring runoff (May or <br />June), and the third sample is collected during base flow conditions <br />(September). Full-suite lab samples collected at all these sites were <br />11 <br />