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not include the units of concentration (mg/1 or ug/1) for each <br />parameter. The units used for each parameter are the same as those <br />listed on the standards table (Table 9) and are also the same as those <br />used in the water quality reports. The frequency column on Table 10 <br />indicates the number of exceedences out of the total number of samples <br />(i.e. , 1/2 indicates one exceedence out of two 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 CDOH 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. <br />Parameter # of Sites / # of Excursions <br />manganese (CDOH irrigation) 11/16 <br />Review of this summary indicates that only one CDOH surface water <br />agricultural use standard was exceeded. The manganese standard was <br />exceeded at seven sites. However, as noted previously in the ground <br />water discussion, the relatively low CDOH standard of 0.2 mg/1, <br />according to the EPA, applies to plants grown in acidic soils. In <br />alkaline soils, as are found in the Seneca II region, a more appropriate <br />(EPA) standard would be 10 mg/1. The maximum manganese value observed <br />this year at any NPDES outfall was 0.43 mg/1 at NPDES 003. All stream <br />sites had manganese values less than 1.0 mg/1. It should also be noted <br />that the site on Grassy Creek (SSG1) that is upstream of Seneca II <br />discharges also experienced exceedences of the 0.2 mg/1 standard. <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 (excluding ammonia <br />and sulfide) are: <br /> <br />20 <br />