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exceedances above the Method Detection Limit (MDL) / the number of <br />exceedances between the MDL and the Practical Quantitation Level (PQL) / <br />censored, that is, the number of sample values below the MDL but the MDL <br />was higher than the standard / the total number of samples. Below is a <br />summary of standards that were exceeded. Given in parenthesis is the <br />source and use of each standard. Although the CDPHE does not indicate <br />between livestock and irrigation uses in their surface water <br />agricultural standards, they have done so in their similar ground water <br />agricultural standards (see Table 5). For the sake of discussion, SCC <br />chooses to use those ground water use standards classifications <br />(livestock or irrigation) for surface water use evaluation. Of all the <br />surface water sites downstream of Seneca II-W, only Sites WSDS (Dry <br />Creek), WSSF3 (Sage Creek), WSH7 (mid-Hubberson Gulch) and WSHF1 (lower <br />Hubberson Gulch) have their waters used for irrigation. Following is a <br />list of standards exceeded this year. <br />Parameter # of Sites / # of Excursions <br />Manganese (CDPHE irrigation) 6/7 0 <br />This summary indicates that only one CDPHE surface water agricultural <br />use standards was exceeded. The manganese standard was exceeded at six <br />sites. However, as indicated in the recently revised CDPHE Regulation <br />31, the standard of 0.2 mg/1, applies to plants grown in acidic (<6.0 <br />pH) soils. In alkaline soils, as are found in the Seneca II-W region, a <br />more appropriate (EPA) standard would be 10 mg/1. The maximum manganese <br />value for any surface water site observed this year was 1.65 mg/l at <br />NPDES6. Premining manganese values often exceeded the 0.2 mg/l standard. <br />Table 12 shows the CDPHE receiving stream standards for Dry Creek (Yampa <br />Segment 13d) and Sage Creek (Yampa Segment 13e). Sage Creek was <br />resegmented by the CDPHE in 2003. Regulation 33 was further revised in <br />December 2005 and August 2008. These standards were based on the <br />presence of fish in the lower portions of the creeks. However, the upper <br />portions that Seneca II-W discharges into have no fish present. All <br />chemical standards for 13d and 13e are currently the same. Table 13 <br />provides a comparison of those standards to water quality data collected <br />20