SITE INFORMATION AND CORRESPONDENCE CASE 2

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INFORMATION SHEET ORDER NO. 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, and rice syrup solids; to a lesser extent they process tea and vegetable 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 has grown greatly since the mid-1990s. 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; an aerated skimmer; and a combination centrifuge and rotary screen to dewater the solids from the skimmer and the DAF units. Prior to discharge, the wastewater is stored in a 13,000 gallon tank. Solids are contained in bins, transported off-site, and used for animal feed. The Discharger optimized operation of the treatment system equipment in 2001, resulting in significant reductions in the BOD concentration of wastewater applied to land. Treated wastewater is currently discharged to 17.6 acre and 16.0 acre land application areas and a 9.2 acre landscaped area. The Discharger has proposed to reconfigure the land areas, selling 7.5 acres of the 17.6 acre land area and adding a new 29.7 acre land application area. The changes will result in a net increase of land area from 46.3 acres to 68.5 acres. The Discharger plans to flood irrigate the land application areas and sprinkler or drip irrigate the landscaped areas. The current average wastewater generation rate is approximately 240,000 gpd. Accounting for near-term growth of the facility, the Discharger anticipates an average generation rate of 429,000 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 flow rates to the land application areas are 370,000 and 429,000 gpd. However, until improvements are made to the proposed additional land application areas and the Executive Officer approves a technical report describing the improvements, the annual average flow to the existing