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present in the alluvium (Hem, 1959, pg. 77). All wells with high iron values exist within the Seneca II permit boundary (except WSAL14). Well WSAL14 is a Sage Creek alluvial well that is downgradien[ of a premining area. Hagh sulfate values may, in part, be due to recharge from the spoil aquifer. Sowever, it must be noted that the CDOH hoe no ground rater agricultural standard for sulfate. This California standard is presented here merely fot comparative purposes. It should also be notetl that six of the twelve walla exhibi Ling high sulfate values did so prior [o mining. High manganese values may, in pazt, be due to r¢charge from the spoil aquifer, although high values are often common, especially in alluvial material (Hem, 1959, pga 56-59). Of the eleven rel is displaying high values, only three (WHAL7-2, WOV17, and WW14) are indicating an increasing trentl fall three exist in the permit area). Three wells in premining areas (WHALE-2, WSAL14, and WW4) also display high values. It should be noted that the CDOH standazd of 0.2 mg/1 is used to protect craps grorn in soils with a pH value lower than 6. 0. In soils with a higher pH (aa are found in the Seneca II-W region), a more appropriate standard would be 10 mg/1. (EPA, 1976). This yeas, none of the Seneca II-W wells displayed a value higher than 2.44 mg/1. At the Seneca II-W sho well (well 201TC) rater atandazda CDOH driNcin were used to • p , g de [ermine its suitability. No human health atandazda were azceeded. The secondary standard £or iron (0.3 mg/1) was exceeded with values of 7.24 and 7.52 mg/1. The secondary standazd for manganese (0.05 mg/1) was exceeded rith values o£ 0 .17 and 0.15 mg/1. Horever, bottled rater ie consumed at Seneca II-W. Also, since the aquifer for the shop well (Trout Creek Sandstone) etazta at 280 feet belor the Wedge Ccal and is separated by confining shale layers, rater from this cell should not be affected by mining and, therefore, reflects the natural chazacteriatica of the aquifer. TDS values at this well exhibit a level TDS trend. Ground Water Quality Su®ary. Increasing TDS trends are beginning to be observed at most wells dorngradient of mining. Horever, one dorngradient roll, WSAL13, exhibits a decreasing TDS trend, and another domgradient well, WW17, ezhiblts a stable TDS trend. Agricultural ground avatar standards rare e:ceaded this year at castain monitoring calla. Tab 7 of the Seneca II-W PAP contains a section that discusses the euitabili ty of using rater from the various aquifers monitored at the Seneca II-W Mina for irrigation or • (0