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�•r %NOV TRIPLE E PRODUCE CORPORATION GROUND WATER TREATMENT AND DISPOSAL FACILITIES SAN JOAQUIN COUNTY INFORMATION SHEET Triple E Produce Corporation operates a fresh market tomato packing facility that uses a chlorination process for preparing tomatoes for market. Ground water beneath the Dischargers' property is contaminated with trihalomethane (THM) constituents. The extent of the contaminated ground water extends from the Discharger's property to approximately 1500 feet north of Linne Road. The primary THM of concern is chloroform, a byproduct of the Discharger's tomato preparation operations. Chloroform in the ground water has been historically as high as 1,900 µg/1 with a more recent average high(Mar 94 through Mar 95) of approximately 500 µg/1. In an effort to lower the chloroform concentrations in the ground water the Discharger has been using in-situ bioremediation techniques since May 1993. The bioremediation technique has been some what successful, however, it has not stopped the migration of the chloroform plume. To control the spread of the chloroform plume in groundwater, the Discharger has proposed to install a new extraction well(XW-1) and to continue pumping monitoring well MW-4A. Installation of XW-1 will increase the ground water extraction rate from 5 gpm to approximately 25 gpm. The extracted ground water will be pumped to an existing aeration pond north of Linne Road for treatment and disposal. There it will be aerated using a spray fountain to remove chloroform contamination. During the summer months, the Discharger estimates that all but 3 gallons per minute (gpm) of the treated ground water will either be evaporated or percolated back to the ground water aquifer. During the winter months, when the evaporation rates are less, the Discharger estimates that approximately 10 gpm will have to be disposed of in an alternative manner. The extra treated ground water that does not evaporate or percolate from the aeration pond, will be pumped to the existing tomato wash water treatment plant for further chloroform removal prior to being sprinklered beneath sixteen acres of apricots adjacent the Dischargers tomato packing facilities. During the winter months, the tomato wash water treatment plant is not in use, making it available without restriction for further treatment of the extracted ground water. During the summer months when the fresh tomatoes are being processed the wash water treatment is used, making it necessary to schedule the ground water treatment operations around the wash water treatment schedule. The WDRs .requires the Discharger to prepare and submit an operations plan for all treatment and disposal operations. Analyses have shown that the existing aeration pond's treatment process has a chloroform removal efficiency of greater than 90%. To be protective of the ground water beneath the aeration pond and to ensure compliance with the State Water Resources Control Board Resolution 68-16,Statement of Policy With Respect To Maintaining High Quality Of Waters In California (Anti-Degradation Policy), the monthly average effluent limit in the aeration pond was set at 20 µg/l. The 20 µg/1 will comply Resolution 68-16 because the contaminant level in the ground water has a greater concentration than the percolating ground water from the aeration pond and the fact that the aeration pond is above the portion of the contaminated ground water plume that will be pulled into the extraction wells. The existing tomato wash water treatment plant uses a low profile air stripping tower that should effectively remove trihalomethane constituents from the pumped ground water to less than 0.5 µg/l. Effluent that is discharged to the apricot orchard spray field will have an effluent limit of 0.5 µg/1 in the WDRs. This lower effluent limit was set in order to comply with Resolution 68-16 since the ground water beneath the apricot orchard spray field has not been impacted by the chloroform or trihalomethane constituents. The beneficial uses of underlying ground water are domestic, industrial, and agricultural supply. To assess the effectiveness of the extraction system in controlling and remediating the migration of the chloroform plume,a ground water monitoring system is required to be installed and a ground water monitoring plan is required to be implemented. Each of the ground water disposal areas is required to have up and down gradient ground water monitoring.