SITE INFORMATION AND CORRESPONDENCE CASE 2

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INFORMATION SHEET ORDER NO. R5-2002-0071 CALIFORNIA NATURAL PRODUCTS WASTEWATER TREATMENT FACILITY SAN JOAQUIN COUNTY California Natural Products (CNP)processes rice and soy into food products such as rice syrup, rice milk,puddings, and rice syrup solids; to a lesser extent they process coffee, tea, and soups. The facility is located in Lathrop with surface water drainage to the San Joaquin River. Water is provided by the City of Lathrop's municipal supply. The plant does aseptic packaging under sterile conditions, requiring heated water from boilers and regular acid/caustic tank and equipment cleaning cycles. Reverse osmosis is used to treat boiler feed water. Operations are conducted year round, five to seven days a week with three shifts per day,with cleanup operations performed as required. CNP has been operating and discharging process wastewater to land since 1985; however,until 1990 the discharge volume averaged less than 100 gallons per day and the wastewater was land applied to two disposal areas within 14 acres of land located adjacent to the processing facility. The food processing facilities and wastewater discharge volume have grown greatly since the mid-1990s. Odor complaints were received in October 1987, July 1997, July 1998,March 2000, and July 2000. The odor was generally related to the land application area. The wastewater generated from the site activities is characterized by a high organic matter and solids content. CNP constructed a pretreatment facility in 1999 and 2000 to reduce the organic load in the process wastewater. Treatment of process wastewater consists of a holding/recycle tank; pH control, dissolved air flotation(DAF) clarifier; a 45-foot diameter, 20-foot high trickling filter; a 600 gallon per minute (gpm) lamella separator; and a combination centrifuge and rotary screen to dewater the solids from the lamella separator and the float from the DAF clarifier. Prior to discharge the wastewater is stored in a 13,000 gallon tank. Screened solids are contained in bins, transported off-site, and used for animal feed. The Discharger has optimized operation of the treatment system equipment in 2001, resulting in significant reductions in the BOD concentration of wastewater applied to land. The treated wastewater is currently discharged to a 17.6 acre land application area and a 9.2 acre irrigated landscape area. The Discharger has proposed to increase the wastewater land application area from 26.8 acres to 46.3 acres by adding a 3.5-acre landscaped area and a 16.0-acre land application area. The Discharger plans to flood irrigate the 17.6 and 16.0 acre land application areas and sprinkler or drip irrigate the landscaped area. The current average wastewater generation rate is 240,000 gpd. Accounting for near-term growth of the facility, the Discharger has proposed an average generation rate of 310,000 gpd. The Discharger currently has an agreement with the City of Manteca to discharge up to 60,000 gpd of wastewater to the municipal system. Based on the anticipated discharge of at least 60,000 gpd of wastewater to the municipal system, the expected annual average and monthly average