SITE INFORMATION AND CORRESPONDENCE CASE 2

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WASTE DISCHARGE REQUIREMENTS ORDER NO.115-2002-0071 -2- CALIFORNIA NATURAL PRODUCTS WASTEWATER TREATMENT FACILITY SAN JOAQUIN COUNTY 8. Products for retail sale are packaged on site. Aseptic packaging under sterile conditions requires hot water from boilers and regular acid/caustic tank and equipment cleaning cycles. Reverse osmosis (RO) is used to treat boiler feed water. RO reject water with a total dissolved solids concentration of approximately 1,200 mg/l is discharged to the process wastewater discharge tank. 9. The specific conductance of the water supply before use by the Discharger ranges from 470 µmhos/cm to 660 µmhos/cm. There is approximately a three-fold increase in total dissolved solids concentration in wastewater. In the past, the Discharger switched from ion exchange to reverse osmosis to reduce the amount of total dissolved solids in the process wastewater. 10. The facility is equipped with a clean in place system. Caustic and acid cleaning solutions (potassium hydroxide solution and nitric acid/phosphoric acid mixture) are recycled several times prior to discharge to the wastewater system. Caustic and acid solutions are neutralized, forming potassium nitrate. The trickling filter then consumes much of the nitrate. Residual potassium and nitrate are further taken up by the cropping activities in the land application areas. 11. CNP has been discharging process wastewater to land since the early 1980s; however, the discharge volume averaged less than 100 gallons per day(gpd)until approximately 1990. Based on the low flow and wastewater characteristics, WDRs were initially waived in accordance with the provisions of Regional Board Resolution 82-036; the Regional Board first adopted WDRs for this discharge in 1998. Much larger flows were discharged to land thereafter. 12. From 1980 to 1997, CND's disposal area was located near the processing facility. The previously used application area locations are presented on Attachment A. The 17.6 acre land application area was developed and irrigation pivots were installed in 1996. 13. In the year 2000, the Discharger trucked approximately 8,000 gallons per week of wastewater to the City of Lathrop Crossroads treatment facility, at the request of the City. This discharge has now been stopped since the City no longer needs the wastewater to assist in their denitrification process. 14. The City of Lathrop and the City of Manteca have permitted CNP to discharge up to 150,000 gpd of process and domestic wastewater to the Manteca wastewater treatment plant through the City of Lathrop's collection system on an interim basis. However,because of declining capacity at the Manteca treatment plant, a discharge maximum of 60,000 gpd was imposed. CNP typically has discharged approximately 50,000 gpd to the municipal system. The RWD states the Discharger will discharge approximately 60,000 gpd of wastewater to the municipal system,barring further restrictions by the City of Manteca or the City of Lathrop. 15. The flow to the municipal system utilizes capacity that is allocated to the City of Lathrop,but not yet used. CNP has purchased a capacity of 200,160 gpd in the expansion of the Manteca wastewater treatment plant that is currently in progress and is currently scheduled to become available in 2003. Additional interim unused future capacity allocated to the City of Lathrop may be temporarily available at the City of Manteca plant. 16. Based on projected increases in CND's wastewater flow rates, additional capacity at treatment plants or additional land application areas will be necessary. CNP has investigated discharging to