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4� 40 <br /> No specific reference is made in the Basin Plan to irrigation of food <br /> crops by receiving waters which contain otherwise adequately treated <br /> effluent. Since one of the functions of the Basin Plan is to provide <br /> guidance to the RWQCB in setting specific waste discharge requirements <br /> for projects in the region, the City does not understand why the CVRWQCB <br /> is proposing to apply such a stringent MPN standard at this time when it <br /> is NOT required by the Basin Plan. <br /> Existing Water Quality in Dredger Cut <br /> Testing of water quality in Dredger Cut, Highline Canal and White Slough <br /> by the City as a part of its self monitoring program has shown that the <br /> background coliform levels in the receiving waters are substantially <br /> higher than Lodi ' s discharge. As a result, the discharge from the White <br /> Slough Water Pollution Control Facility is currently improving the <br /> coliform levels in the receiving waters. Water quality monitoring has <br /> shown that there are high coliform concentrations in Highline Canal , <br /> which is tributary to Dredger Cut and which drains a large area of dairy <br /> farms and feedlots. In addition, the coliform concentrations in White <br /> Slough are considerably higher than current discharge requirements. <br /> Adopting a more stringent disinfection standard for the Lodi discharge <br /> will not significantly improve the coliform concentrations in Dredger <br /> Cut, Highline Canal or White Slough. <br /> Disinfection Standard Based on Title 22 Is Not Warranted <br /> A stringent disinfection standard based on Title 22 of the California <br /> Code of Regulations is not warranted in this situation because: <br /> ° Receiving water quality does not currently meet Title 22 Standards <br /> • Title 22 applies to irrigation of food crops with RECLAIMED EFFLUENT <br /> ONLY <br /> • Recreational use of Dredger Cut is extremely limited <br /> ° Other less expensive mitigation measures are available <br /> Title 22, which is referenced in the September 9th letter, applies to <br /> situations where RECLAIMED EFFLUENT ONLY, not a mixture of effluent and <br /> receiving water, is used for the irrigation of food crops. In the Lodi <br /> project, highly treated and disinfected secondary effluent will be <br /> discharged to Dredger Cut during the period from May 15 through October <br /> 15 EXCEPT during periods when effluent quality does not meet waste <br /> discharge requirements or when industrial flows are not sufficient to <br /> satisfy the irrigation demands of the City' s land disposal areas. Highly <br /> treated secondary effluent, when it is discharged to Dredger Cut during <br /> the irrigation season, will be diluted with other Delta waters before it <br /> is used for irrigation of food crops. The EIR estimated an average <br /> dilution of at least 6 to 1 will be achieved in Dredger Cut. The <br /> proposed disinfection requirement does not make any allowance for this <br /> dilution. <br /> In fact, there are only two situations where Title 22 requires an MPN of <br /> 2.2 (monthly median)/23 (daily maximum) total coliform/100 mL when <br /> RECLAIMED EFFLUENT ONLY is used to irrigate food crops: <br /> 1) Spray irrigation of food crops or in situations where food crops will <br /> be in direct contact with RECLAIMED EFFLUENT. In this case, Title 22 <br /> requires that the effluent be treated by coagulation and filtration in <br /> 4 <br /> J <br />