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REGIONAL BOARD RESPONSE (SWRCB/OCC FILE A-1483) -12- PETITION FOR REVIEW OF WASTE DISCHARGE REQUIREMENTS ORDER NOS. R5-2002-0083 AND R5-2002-0084 CITY OF STOCKTON REGIONAL WASTEWATER CONTROL FACILITY 22 filtration should be required. Subsequent installation of the flow monitoring station by USGS and recording of actual flows at Stockton demonstrated little or no dilution exists for days or weeks at a time. With this information it was concluded that Title 22 filtration is needed and the HRA study was not relevant. After consultation with the California Department of Health Services (DHS) regarding this project,DHS recommended the wastewater be treated to tertiary standards (filtered) to protect body contact water recreational uses. DHS has developed reclamation criteria, California Code of Regulations, Title 22, Division 4, Chapter 3, (Title 22) for the reuse of wastewater. Title 22 requires that for spray irrigation of food crops,parks, playgrounds, school yards and other areas of similar public access, that wastewater be adequately disinfected, oxidized, coagulated, clarified and filtered and that the effluent total coliform levels not exceed 2.2 MPN/100 ml as a 7-day median. To protect the beneficial use of domestic supply, irrigation, and contact recreation in a receiving stream with less than 20:1 dilution, DHS recommends treatment to Title 22 standards. In addition, filtration is an effective means of reducing viruses and parasites from the waste stream. Using SJR-flow data, dilution ratios over the 7-day and 30-day low flow periods during wet years are approximately 1.2:1 and 2.7:1. During dry years there may be no dilution over these averaging periods. During slack tide periods there will also be no available dilution. The Regional Board found that it is appropriate to apply DHS's reclamation criteria.and DHS's site- specific recommendations for the SJR to the discharge because the SJR is used for agriculture, domestic, and body contact water recreation purposes. The reclamation criteria are appropriate to apply since body contact water recreation would result in similar or greater exposure than the activities specifically included in those regulations and Title 22. Moreover, the more stringent disinfection criteria of Title 22 are appropriate since relatively undiluted effluent may be used for the irrigation of food crops or for golf courses and parks. Additionally,based on testimony of Lt. Dennis DeAnda from the Department of Fish and Game 4, Joseph Spano from the California Department of Health Services-5, and Bill Jennings of Deltakeeperb, subsistence fishing and shellfish harvesting are a common occurrence near the point of discharge year-round, which supports the requirement to provide tertiary treatment year-round rather than only during the summer. The State Board has previously held that the Regional Board can properly consider the reclamation(now recycled water) criteria where wastewater is discharged under circumstances that are analogous to the direct reuse of recycled water. See State Board Order WQ 86-14. The City has developed a Health Risk Assessment Study,which claims that tertiary treatment during the winter is unnecessary. However, the study did not assess the health risk due to shellfish harvesting. (Shellfish harvesting was not recognized as a potential health problem in the 1994 Permit, so it was not included in the HRA study.) DHS has reviewed the study and still recommends year-round Title 22 tertiary treatment for the protection of public health. 4 Transcript from the 26 April 2002 Central Valley Regional Water Quality Control Board hearing,Pgs 107-110 5 Ibid.Pgs. 115-116 6 Ibid.Pg. 106 7 12 April 2002 letter from DHS to CV RWQCB(Administrative Record,Binder 1,Item 13)