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Well HGDAL4 is upgradient of the Loadout. It was drilled in 2005. It <br />displays an increasing TDS trend, with the peak TDS value occurred in <br />May 2012. <br />This year's ground water quality was compared against CDPHE ground water <br />agricultural use standards (CDPHE, Reg. 41, 2008) . Results of those <br />comparisons are presented in Table 4. <br />Both wells exceeded the manganese standard (0.2 mg /1) in both May and <br />September. It should be noted that, while the CDPHE uses a manganese <br />standard of 0.2 mg /l, the EPA states that this standard is used to <br />protect crops grown in soils with a pH value lower than 6.0. In January <br />2008, CDPHE revised their ground water agricultural standard to reflect <br />this pH qualifier. In soils with a higher pH (as are found in the HGT <br />region), a more appropriate standard would be 10 mg /1 (EPA. 1976. <br />"Quality Criteria for Water "). This year, neither of the Loadout wells <br />displayed a manganese value higher than 5.255 mg /l. <br />Downgradient Well HGDAL3 exceed the boron standard, 750 ug /1, with a <br />value of 880 ug /1 in September. According to the CDPHE, the 750 ug /1 <br />standard is set for sensitive crops (CDOH, Reg. 41, 2008), and that the <br />limit otherwise is 5000 ug /l. None of these sensitive plant species are <br />grown commercially in this area. <br />All four samples from both wells had cadmium values that were less than <br />an elevated detection limit (30 or 50 ug /l, vs. a normal detection limit <br />of 10 ug /1), which was higher than the CDPHE standard of 10 ug /1. <br />Likewise, the same samples had lead values that were less than an <br />elevated detection limit (200 or 400 ug /l, vs. a normal detection limit <br />of 20 ug /1), which was higher than the CDPHE standard of 100 ug /l. The <br />cause of this elevated detection limits was a decision by the laboratory <br />to dilute the sample prior to analyses in order to reduce the effects of <br />interferences (primarily, high salinity). <br />In a letter dated June 5, 2008, Tom Kaldenbach of the CDRMS stated that <br />"Groundwater points of compliance are unwarranted at the Hayden Gulch <br />Loadout...". He further concluded that "... any leachate originating at the <br />5 <br />