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WASTE DISCHARGE REQMENTS -6- STOCKTON COGENERATIM, COMPANY SAN JOAQUIN COUNTY considered as dissolved when compared to dissolved criteria. Of seven samples collected and analyzed for arsenic biannually between January 1997 and January 2000, all were above the State of California Proposition 65 Regulatory Drinking Water Level of 5 µg/l for arsenic. Effluent concentrations ranged between 20 and 26 µg/l. Data indicates that the source of the arsenic is the groundwater that is the supply for the majority of the cooling tower feedwater. There is no arsenic added in any part of the SCC operation. Because development of effluent limits will now consider beneficial uses of North Littlejohns Creek, this Order provides for a time schedule for meeting the effluent limitation for arsenic. A compliance schedule is being allowed under Provision G.3 and is authorized to be included in this Order based on 40 CFR §122.47. 22. The water quality objective for the protection of agricultural use for molybdenum is 10 µg/1 as an annual average. Of seven samples collected and analyzed for molybdenum biannually between January 1997 and January 2000, four samples were at or below 5.0 µg/1, one was 9.0 µg/l, one was 15 µg/l, and one was non-detect with a detection limit of 20 µg/l. The data indicates that there is a reasonable potential for the discharge to cause or contribute to an in-stream excursion above the water quality objective for molybdenum. An effluent limit for molybdenum of 10 pg/l annual average is included in this permit in order to protect the beneficial uses of the receiving stream. 23. Previous permits issued for this facility contained a receiving water limitation requiring the discharge to not cause receiving water dissolved oxygen to fall below 5.0 mg/l. However,because the beneficial use of cold freshwater habitat applies to this stream segment, the Basin Plan water quality objective for dissolved oxygen of 7.0 mg/l is applicable. This permit applies a water quality objective to North Littlejohns Creek that has never been applied to this specific area of the water body. It is unknown if the Discharger is currently capable of meeting this receiving water limitation. This order provides for a time schedule for meeting the receiving water limitation. The time schedule is authorized to be included in this order based on 40 CFR §122.47. The Board considers the application of a water quality objective that has never been applied to North Littlejohns Creek as a new interpretation of the Basin Plan. 24. Section 13267(b) of California Water Code provides that: "In conducting an investigation specified in subdivision (a), the regional board may require that any person who has discharged, discharges, or is suspected of discharging, or who proposes to discharge within its region, or any citizen or domiciliary, or political agency or entity of this state who has discharged, discharges, or is suspected of discharging, or who proposes to discharge waste outside of its region that could affect the quality of the waters of the state within its region shall furnish, under penalty of perjury, technical or monitoring program reports which the board requires. The burden, including costs of these reports, shall bear a reasonable relationship to the need for the reports and the benefits to be obtained from the reports." 25. The action to adopt an NPDES permit is exempt from the provisions of Chapter 3 of the California Environmental Quality Act (CEQA) (Public Resources Code Section 21100, et seq.), requiring