SITE INFORMATION AND CORRESPONDENCE_FILE 1

Home Browse Search

U �.J Wendy L. Cohen -3- 15 March 1994 7 xylenes up to 862 ppb. The single ground water sample from Trench A contained TPH-D at 68 ppm, ethylbenzene at 7 ppb, and total xylenes at 183 ppb. Also in September 1992, Erler & Kalinowski, Inc. (EKI) completed another investigation of the area working for Texaco and Chevron. This report is not in our files. The investigation included drilling of five additional monitoring wells, three on the Dividend Property (MW-20 through MW-22) and two within the Southern Railroad right-of-way (MW-23 and MW-24). Eight soil borings also were drilled in the right-of-way (SB-1 through SB-8). Sample analysis for the soil and ground water were included in a subsequent report. Every soil boring had petroleum contamination which ranged from 1,841 through 23,907 ppm total recoverable petroleum hydrocarbons (TRPH). Ground water samples ranged from nondetect to 4,900 ppb total extractable petroleum hydrocarbons (TEPH) and up to 5,900 ppb total purgeable petroleum hydrocarbons. After the submittal of the last TTI report, the Dividend Development Corporation took legal action against Texaco Trading and Transporation, Inc. and Chevron Pipeline Company for the site contamination. Within less than a year the action was settled out of court with an agreement that Texaco and Chevron would clean up the petroleum contamination on the site under the direction of the Regional Board. Recent Submittal In November 1993 EKI submitted a Remediation Plan for the Dividend Property, prepared for Texaco and Chevron. This report states that the remedial design objective for the ground water is to prevent migration of floating heavy hydrocarbons onto the Dividend Property. The remedial design objective for the soil is based upon the results of risk assessments performed for other similar sites in California. The plan also contains a review of alternative remedial actions for the soil and ground water. The selected remedial action for the contaminated soil is no action, except for a proposed notice to be given to workers and future residents for excavations below 4-5 feet bgs where contamination exists. The selected remedial action for the ground water is to install interceptor trenches along the edge of the property line adjacent to the Southern Pacific right-of- way. In addition, the plan calls for passive skimming of free product from sumps constructed at the end of the interceptor trenches. In summary, 48 test pits and trenches have been dug, 17 soil borings drilled, and 22 monitoring wells installed. Soil and ground water are contaminated with petroleum hydrocarbons. Ground water contamination has been measured up to the following levels: 4,900 ppb TEPH, 5,900 ppb TRPH, 170 ppm TPH-motor oil, 68 ppm TPH-D, 5.1 ppb benzene, 183 ppb total xylenes, and free product floating in monitoring wells and trenches. The soil is contaminated up to 23,907 ppm TRPH.