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within the Seneca II permit boundary. Well 71 is upstream of Seneca II <br />discharges. <br />High manganese values may, in part, be due to recharge from the spoil <br />aquifer, although high values are often common, especially in alluvial <br />material (Hem, 1989, pgs. 86-89). Of the fourteen wells displaying high <br />values, only seven (SGAL70, SLGAL3IA, SLGAL32, SLGAL6, SSP61, SSP62 and <br />SWU7) are indicating an increasing trend. The one Grassy Creek alluvial <br />well upstream of Seneca ZZ (71) also displays high values. It should be <br />noted that, while the CDOH uses a standard of 0.2 mg/1, the EPA states <br />that this standard is used to protect crops grown in soils with a pH <br />value lower than 6.0. In soils with a higher pH (as are found in the <br />Seneca II region), a more appropriate standard would be 10 mg/1 (EPA, <br />1976). This year, none of the Seneca IZ alluvial wells displayed a <br />value higher than 7.45 mg/1, and no spoil wells displayed a value higher <br />than 0.96 mg/1. <br />Finally, water quality analyses performed on samples obtained at the <br />Seneca II shop well (STCS) for this year were compared against both <br />human health (mandatory) and secondary (i.e., recommended but not <br />mandatory) drinking water standards developed for ground water by the <br />CDOH. No human health standards were exceeded. The CDOH secon dary <br />standard for sulfate, 250 mg/1, was exceeded twice with values of 420 <br />and 410 mg/1. Well STCS has historically exhibited sul fate <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 four 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 />(o <br />