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• 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 nine wells displaying high <br />values, only two (WHAL7-2 and WW14) are indicating an increasing trend <br />(both exist in the permit area). It should be noted that, while the CDOH <br />uses a standard of 0.2 mg/1, the EPA states that this standard is used <br />to protect crops grown in soils with a pH value lower than 6.0. In soils <br />with a higher pH (as are found in the Seneca II-W region), a more <br />appropriate standard would be 10 mg/1 (EPA, 1976). This year, none of <br />the Seneca II-W wells displayed a value higher than 2.99 mg/1. <br />One well, WW14, exhibited boron values, 970 and 1090 ug/1, which <br />exceeded the CDOH standard of 750 ugJl. According-to the CDOH, the 750 <br />ug/1 standard is set for sensitive crops (CDOH, Reg. 41, 1999), and that <br />the limit otherwise is 5000 ugJl. None of these sensitive plant species <br />are grown commercially in this area. <br />At the Seneca II-W shop well, Well 201TC, CDOH drinking water standards <br />were used to determine its suitability. No human health standards were <br />exceeded. The secondary standard for iron (0.3 mg/1) was exceeded with <br />values of 1.77 and 9.78 mg/1. The secondary standard for manganese (0.05 <br />mg/1) was exceeded with values of 0.165 and 0.227 mg/1. However, bottled <br />water is consumed at Seneca II-W. Also, since the aquifer for the shop <br />well (Trout Creek Sandstone) starts at 280 feet below the Wadge Coal and <br />is separated by confining shale layers, water from this well should not <br />be affected by mining and, therefore, reflects the natural <br />characteristics of the aquifer. <br />Ground Water Oualitv Summarv. Increasing TDS trends are beginning to be <br />observed at most wells downgradient of mining. However, two downgradient <br />wells, WSAL12 and WOV17, exhibit a stable TDS trend. <br />Agricultural ground water standards were exceeded this year at certain <br />monitoring wells. Tab 7 of the Seneca II-W PAP contains a section that <br />. discusses the suitability of using water from the various aquifers <br />monitored at the Seneca II-W Mine for irrigation or livestock watering. <br />I1 <br />