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Table 10 provides a comparison of all surface water quality data this year to agricultural standards. This Paradox database generated table does not include the units of concentration (mg/1 or ug/1) for each parameter. The units used for each parameter are the same as those listed on the standards table (Table 9) and are also the same as those used in the water quality reports. The frequency column on Table 10 indicates the number of exceedences out of the total number of samples (i.e., 1/2 indicates one exceedence out of two samples). Below is a summary of standards that were exceeded. Given in parenthesis is the source and use of each standard. Although the CDOH does not indicate between livestock and irrigation uses in their surface water agricultural standards, they have done so in their similar ground water agricultural standards (see 'Cable 5). For the sake of discussion, SCC chooses to use those ground water use standards classifications (livestock or irrigation) for surface water use evaluation. of Sites / # of Excursions Manganese (CDOH irrigation) Cadmium (CDOH irrigation) Nickel (CDOH irrigation) 10/16 1/1 1/1 This summary indicates that only three CDOH surface water agricultural use standards were exceeded. The manganese standard was exceeded at ten sites. However, as indicated in the recently revised CDOH Regulation 31, the standard of 0.2 mg/1, applies to plants grown in acidic (<6.0 pH) soils. In alkaline soils, as are found in the Seneca II region, a more appropriate (EPA) standard would be 10 mg/1. The maximum manganese value observed this year at any NPDES outf all was 0.66 mg/1 at NPDES 003. All stream sites had manganese values less than 0.60 mg/1, and all spoil springs were less than 10 mg/1. It should also be noted that the site on Grassy Creek (SSG1) that is upstream of Seneca II discharges also experienced exceedences of the 0.2 mg/1 standard. Spoil Spring 6 exceeded the nickel standard for irrigation (200 ug/1) with a value of 260 ug/1, and the cadmium standard for irrigation (1C L 20