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lead, and fluorides may he attrihuted to natural (v.e., not mining related) conditions, <br />since elevated levels for those parameters are not found in Seneca II spoil wells. <br />In the case of Fluorides, the three wells (B P1, it and 19) that have elevated levels have <br />historically displayed hvgh levels. Those wells are also unique in displaying a podium <br />bicarbonate type water: with almost no calcium, magnenvum, or sulfates; and with <br />relatively high pH values. It is suspected that the high fluoride values era related to <br />this type of water chemistry (Hem, 1989, pg. 121). All three wells exist within the Seneca <br />II permit boundary. <br />In the case of iron, the one Wedge Underburden well (7) exhibiting high levels may have <br />high than usual concentrations of iron pyrite in the rock. The high levels of iron <br />displayed in the two alluvial wells 132 and 33) may De the result of organic matter and <br />plant debris present in the alluvium (Hem, 1989, pg. 77). All three wells exist within <br />the Seneca II permit boundary. <br />The one high lead value observed' at alluvial Well 31A is considered to be an erroneous <br />value. This, or no other alluvial or spoils well at Seneca II has ever exhibited such a <br />high value. <br />High sulfate values may, in part, be due'to recharge from the spoil aquifer. However, it <br />must be noted that the CDOH has no ground water agricultural standard for sulfate. This <br />Calvfornia standard is presented here merely for comparative purposes. It should also be <br />noted that the one Grassy Creek alluvial well (71) upstream of Seneca II also exhibits <br />high sulfate values. <br />High manganese values may, an part, be due to recharge from the spoil aquifer, although <br />high values are often common, especially in alluvial ma terval (Hem, 1989, pga. 86-891 Of <br />the thirteen wells displaying high values, only five (SLGAL70, SLGAL3IA, SLGAL6, SSP62, <br />and SWU7) are indicating an increasing trend. The one Grassy Creek alluvial well upstream <br />of Seneca II (71) also displays high values. It should be noted that the CDOH standard of <br />0.2 mg/1 is used to protect crops grown rn souls with a pH value lower than 6. 0. In soils <br />with a higher pH (as aze found in the Seneca II region), a more appropriate standard would <br />be 10 mg/1. (EPA, 1976) . This year, none of the Seneca II alluvial wells displayed a <br />value higher than 6.4 mg/1, and no spoil we119 displayed a value higher than 1.33 mg/1. <br />9 <br />