SITE INFORMATION AND CORRESPONDENCE_FILE 1

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INFORMATION SHEET OCCIDENTAL CHEMICAL AGRICULTURAL PRODUCTS, INC. LATHROP, SAN JOAQUIN COUNTY As of 1 January 1983, Occidental Chemical Agricultural Products, Inc. (OCAP, for- merly Occidental Chemical Company) conveyed to the J.R. Simplot Company (Simplot) certain property and assets of the agricultural chemical production facility located at 16777 South Howland Road, one mile south of Lathrop in San Joaquin County, Section 35, T1S, R6E, MDB&M. Not included in the conveyance, but retained by OCAP, were the ground water remedial system, its supporting laboratory, records, and equipment, the phosphoric acid production plant, and the aqua recovery system. Under terms of the Stipulation and Judgment Approving Settlement (No. CIV S-79-989 MLS, hereafter Stipulation) entered as of 3 April 1981 in the civil action between the United States of America and the State of California versus Occidental Chemical Company, OCAP is responsible for mitigation, cleanup, and abatement of any contam- ination of ground water attributable to operations at the Lathrop facility. Per- formance of obligations under the Stipulation is unconditionally guaranteed by Occidental Petroleum Corporation. Conveyance of the Lathrop facility from OCAP to Simplot does not alter this responsibility. Samples of the ground water collected in the vicinity of the Lathrop property contain sulfates, dibromochloropropane (DBCP), sulfolane, ethylene dibromide (EDB), lindane and other isomers of BHC, dimethoate and disyston. The ground water will be cleaned up by containing the contaminated ground water through computer based placement of five extraction wells, treating the extracted ground water through activated carbon adsorption, and disposing of the treated water to a confined and unuseable aquifer isolated from useable shallower ground water. The activated carbon adsorption treatment will remove the toxic organic chemicals to levels below established drinking water standards or state action levels. Sulfolane, a rela- tively nontoxic (chronic and acute) chemical, will not be efficiently removed (<15%) by the carbon adsorption system. Sulfates found in the ground water at levels as high as 6800 mg/1, will not be removed by the activated carbon adsorption system. The effect of not removing the sulfate and sulfolane will be insignificant as the injection aquifer is unuseable for domestic or agricultural uses because of high chloride levels (>1000 mg/1) and the aquifer is confined and isolated from useable waters by a thick blue clay cap commonly referred to as the Corcoran clay layer. The ground water remedial system commenced operation 21 June 1982 under waste discharge requirements established by Order No. 82-099. Performance of the ground water remedial system is regulated jointly by the Board, State Department of Health Services, State Department of Justice and US EPA through the Stipulation. TRP:dg 3/02/83