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.~ ug/1) with a value of 10.9 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 ni ckel, and 50 ug/1 for cadmium. This spring <br /> eventually flows into Pond 002, which did not exceed the nickel or <br /> cadmium standards. <br />L <br /> <br />Table 11 shows the CDOH receiving stream standards for Fish Creek (Yampa <br />Segment 13b). 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 are: <br />Parameter # of Sites / # of Excursions <br />Iron, Total Rec. 2/2 <br />Sulfide 3/3 <br />One sample (from NPDES8) had a selenium value that was less than an <br />elevated detection limit (5 ug/1 vs. a normal detection limit of 1 <br />ug/1), which was higher than the CDOH standard of 4.6 ug/1 (chronic). <br />The cause of this elevated detection limit was a decision by the <br />laboratory to dilute the samples prior to analyses in order to reduce <br />the effects of interferences (such as high salinity). <br />All iron excursions were the result of high suspended solids. None of <br />the iron excursions were at a NPDES site. <br />Three samples experienced exceedences of the sulfide standard (0.002 <br />mg/1 un-ionized) this year. One of these excursions was from a stream <br />above Seneca's discharges. The analytical method available to SCC <br />detects both dissolved sulfides and acid-soluble metallic sulfides <br />present in suspended matter. It is suspected that a large portion of the <br />sulfides detected is of the latter type, which would bias the un-ionized <br />results high. Any dissolved sulfides present in surface water should <br />eventually oxidize to sulfates. <br />In September 2003 (effective January 2004), the CDOH resegmented Grassy <br />Creek from Yampa Segment 12 to Segment 13e. Regulation 33 was further <br />21 <br />