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,' Table 10 provides a comparison of surface water quality to agricultural <br />standards. This Paradox database generated table does not include the <br />units of concentration (mg/1 or ug/1) for each parameter. The units used <br />for each parameter are the same as those listed on the standards table <br />(Table 9) and are also the same as those used in the water quality <br />reports. The frequency column on Table 10 indicates the number of <br />exceedences out of the total number of samples (i.e., 1/2 indicates one <br />exceedence out of two samples) . Below is a summary of standards that <br />were exceeded. Given in parenthesis is the source and use of each <br />standard. Although the CDOH does not indicate between livestock and <br />irrigation uses in their surface water agricultural standards, they have <br />done so in their similar ground water agricultural standards (see Table <br />5). For the sake of discussion, SCC chooses to use those ground water <br />use standards classifications (livestock or irrigation) for surface <br />water use evaluation. Following is a list of standards exceeded this <br />year. <br />Parameter # of Sites / # of Excursions <br />Manganese (CDOH, SW, irrigation) 3/4 <br />Review of this list indicates that only one CDOH surface water <br />agricultural use standards was exceeded. The manganese standard was <br />exceeded at three 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 Yoast region, a more appropriate <br />(EPA) standard would be 10 mg/1. The maximum manganese value for any <br />surface water site observed this year was 1.06 mg/1. Premining manganese <br />values often exceeded the 0.2 mg/1 standard. <br />Table 11 shows the CDOH receiving stream standards for Sage and Grassy <br />Creeks (Yampa Segment 13 e, Reg. 33, 2003). These standards were based on <br />the presence of fish in the lower portions of the creeks. However, the <br />upper portions that the Yoast Mine discharges into have no fish present. <br />Table 12 provides a comparison of those standards to water quality data <br />collected this year from NPDES and stream sites in the Sage and Grassy <br />13 <br />