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sites had manganese. values less than 0.50 mg/1. it should also be noted <br />that the site on Grassy Creek (SSGl) that is upstream of Seneca II <br />discharges also experienced exceedences of the 0.2 mg/1 standard. <br />Spoil Spring 6 exceeded the nickel standard for irrigation (200 ug/1) <br />with a value of 210 ug/1. However, this water is not used for <br />irrigation. The National Academy of Science suggests a livestock <br />standard of 1000 ug/1 for nickel. <br />Table 11 shows the CDOH receiving stream standards for Fish Creek (Yampa <br />Segment 13 b). Table 12 provides a comparison of those standards to <br />water quality data collected this year from NPDES and stream sites in <br />the Fish Creek basin. Standards that were exceeded (excluding ammonia <br />and sulfide) are: <br />Parameter # of Sites / # of Excursions <br />Selenium (chronic) 2/2 <br />Nitrite 2/2 <br />NPDES4 and NPDESS exceeded the chronic (30 day average) selenium <br />standard once each, but not the acute (one day max.) standard. The CDOH <br />standard is for they dissolved form, SCC analyzes the total recoverable <br />form. The same two samples also exceeded the nitrite standard. Nitrites <br />will rapidly oxidize to nitrates. All of these excursion occurred in <br />April, when high flows in Fish Creek would have diluted these <br />concentrations. <br />In addition, a toted of six samples (from NPDES4 and 8 and SSB12) had <br />chromium values that were less than an elevated detection limit (20 ug/1 <br />vs. a normal detection limit of 10 ug/1), which was higher than the CDOH <br />standards of 11 ucr/1 (chronic) and 16 ug/1 (acute). Likewise, one <br />sample (from NPDES4) had a copper value that was less than an elevated <br />detection limit (50 ug/1 vs. a normal detection limit of 10 ug/1), which <br /> was higher than the: CDOH standard of 29 ug/1 (chronic). The cause of <br /> these elevated detection limits was a decision by the laboratory to <br />21 <br />