SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

• s INFORMATION SHEET STOCKTON COGENERATION COMPANY SAN JOAQUIN COUNTY The Stockton Cogeneration Company(SCC) owns a 49.9 megawatt net sales (nominal 60 megawatt gross output) cogeneration plant in Stockton. The operator of the facility is Air Products Manufacturing Corporation. The facility is a coal and petroleum coke fired circulating fluidized bed steam electric cogeneration plant that generates steam and electric power. The steam and some of the electricity are supplied to the neighboring Corn Products Corporation facility, and the remaining electricity produced is sold to Pacific Gas and Electric Company. The Discharger generates dechlorinated cooling tower blowdown together with other internal low volume wastes that are discharged from Outfall 001 to North Littlejohns Creek. All other sanitary and process wastewater generated by this facility is discharged to the City of Stockton Municipal Utilities System and is not covered by this NPDES permit. The Discharger requested in their Report of Waste Discharge dated 23 November 1999 an increase in the maximum allowable discharge flow to 1.3 mgd from the 0.9 mgd in their previous WDRs (Order No. 95-148). In evaluating such a request the Board must consider anti-degradation pursuant to 40 CFR 131.12 and SWRCB Resolution No. 68-16. Historical effluent data finds the toxicity of the effluent to be less than downstream receiving waters and dissolved oxygen to higher than both the receiving water and applicable Basin Plan water quality objectives. These are considered benefits to the receiving water. Also, constituents for which the Discharger has permanent or interim effluent limits are not bioaccumulative nor are they responsible for downstream impairment or 303(d) listing. Based on these findings the Board finds that the proposed increase in the maximum allowable discharge will have an insignificant impact on beneficial uses and is therefore acceptable. The Discharger applies up to 100,000 gallons per day to a 7.4-acre vacant industrial lot and also utilizes effluent for landscape irrigation on site. The Discharger has previously been granted a waiver of discharge requirements for land application of non-contact cooling water. This permit contains requirements that must be met in order for the Discharger to continue to apply effluent to land. The previous Order contained provisions concerning storm water. This Order does not contain such provisions, and the Discharger must seek coverage under the General Order. The State Water Resources Control Board adopted Order No. 97-03-DWQ (General Permit No. CAS000001) specifying waste discharge requirements for discharges of storm water associated with industrial activities, excluding construction activities, and requiring submittal of a Notice of Intent by industries to be covered under the permit. Federal regulations require effluent limitations for all pollutants that are or may be discharged at a level that will cause or have a reasonable potential to cause, or contribute to an in-stream excursion above numerical or water quality standard. The Discharger is required to provide information as to whether the levels of priority pollutants, including CTR and NTR constituents, and constituents for which drinking water maximum contaminant levels prescribed in the California Code of Regulation, in the discharge cause or contribute to an in stream excursion above a water quality objective. If the discharge has the reasonable potential to cause or contribute to an in-stream excursion above a water quality objective, the Discharger is required to submit information to calculate effluent limitations for those constituents.