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material (Hem, 1989, pgs. 86-89). This standard is used to protect crops • <br />grown in soils with a pH value lower than 6.0. In January 2008, CDPHE <br />revised their ground water agricultural standard to reflect this pH <br />qualifier. In soils with a higher pH (as are found in the Seneca II-W <br />region), a more appropriate standard would be 10 mg/l (EPA, 1976). This <br />year, none of the Seneca II-W wells displayed a value higher than 2.02 <br />mg/l. <br />One well, WW14, exhibited a boron value of 1100 ug/1, which exceeded the <br />CDPHE standard of 750 ug/l. This well commonly exceeds the boron <br />standard. According to the CDPHE, the 750 ug/1 standard is set for <br />sensitive crops (CDPHE, Reg. 41, May 2008), and that the limit otherwise <br />is 5000 ug/l. None of these sensitive plant species are grown <br />commercially in this area. <br />Well WOV17 exhibited elevated values for selenium and zinc this year. <br />These values are attributed to the elevated TDS values noted at this <br />well this year (see previous Wadge Overburden section). More data will • <br />be needed to determine if these values are anomalies. <br />At the Seneca II-W shop well, Well 201TC, CDPHE 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 a <br />value of 7.86 mg/1. The secondary standard for manganese (0.05 mg/1) was <br />exceeded with a value of 0.152 mg/1. Both of the standards are normally <br />exceeded at this well. However, bottled water is consumed at Seneca II- <br />W. Also, since the aquifer for the shop well (Trout Creek Sandstone) <br />starts at 280 feet below the Wadge Coal and is separated by confining <br />shale layers, water from this well should not be affected by mining and, <br />therefore, reflects the natural characteristics of the aquifer. <br />Ground Water Points of Compliance <br />A GWPOC have been established in the Dry Creek alluvium for the Seneca <br />II-W Mine. Appendix 15-3B of the Seneca II-W PAP provides the details. <br />The ground water standards for Dry Creek Alluvial Well DCAL-02 are <br />10