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Mr. Robert Meleg - 5 - 22 July 2003 Public Works Director constructed wetlands. If the City wishes to proceed with this project, it will need to submit additional information demonstrating that the application of this treatment technology is BPTC and protective of underlying groundwater quality. The RWD indicates that the City has issued industrial user permits to three primary industrial users: (1) California Fruit and Tomato Kitchens (CF&TK), a tomato processor, (2)Don Francisco Foods (DFF), a cheese manufacture, and(3)Norries Industries (NI), an army ammunition producer. The two food processing industries monitor and have effluent limits for pH, BOD loading,flow, and temperature. The ammunition producer monitors and has limits for pH, total dissolved solids (TDS),flow, and temperature. The RWD recommends conducting additional monitoring of all industrial users weekly for TDS, and annually for general minerals and heavy metals. Some studies have been conducted already to reduce the salt loadings. The additional monitoring will provide information to characterize the overall quality of wastewater discharged to the WWTF. Existing monitoring already shows effluent EC is approximately 400 µmhos/cm greater than the EC during the non-cannery season. The RWD indicates that NI will reduce the number of backwash cycles of its ion exchange units, which would reduce TDS discharged to the WWTF by 10 percent. The RWD also indicates that the City expects CF&TK to reduce its TDS contribution to the WWTF by 10 percent but does not identify the sources of TDS at CF&TK or how TDS will be reduced. Because groundwater monitoring within the WWTF vicinity indicates water quality limits are exceeded in groundwater for salinity constituents, the City should conduct thorough inspections of each industrial user to identify all high salinity sources and, if deemed necessary, require the industrial user to implement additional salinity source control and reduction and, where appropriate, remove such sources from its discharge stream (e.g.,brine wastes). The City should determine whether or not CF&TK utilizes lye in its peeling process. Implementation of non-lye peeling technology may be required to ensure this industrial discharge does not contribute to pass-through for salinity constituents. The RWD contains additional constitutes to further characterize the quality of the effluent during the non-cannery season (mid-July to October) and proposes conducting further monitoring to characterize the effluent during the cannery season. The additional effluent monitoring data indicates that the majority of the total nitrogen in the effluent is in the form of organic or ammonia nitrogen. In June 2003, the monthly average nitrogen concentrations were characterized as follows: total nitrogen (21 mg/), total Kjeldahl nitrogen (21 mg/L), nitrate (as N) (non-detect), and ammonia(as N) (10 mg/L). Previously, the City assumed that total nitrogen consisted primarily of ammonia and nitrate and negligible concentrations of organic nitrogen. Representative monitoring during the cannery season will likely reveal that a large portion of the nitrogen is in organic form, significantly increasing the overall total nitrogen concentration, and the discharge's potential impact on groundwater. The RWD includes a brief description of the City's efforts to investigating recycling all its effluent. The RWD indicates that it would take approximately 780 acres of land to recycle all of its effluent, which would take several years to fully implement.