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�./ 20 KLEIN FELDER limit lateral migration of crude oil, recover free product with a vacuum truck and to remove contaminated oil saturated soil. Limited soil sampling and analyses and backhoe exploration was performed to assess the lateral and vertical limits of oil-impacted soil. Oil impacted soil was reported at depths ranging from 5 to 9 feet below ground surface (bgs), although vertical migration was noted as "ongoing." Therefore, the oil still appeared vertically mobile, potentially migrating to deeper depths over time. The apparent lateral extent of oil impacted soil is shown on Cambria's Figure 3 in this report, which shows an irregular shape area at approximate maximum dimensions of 380 by 380 feet. Chevron estimated that approximately 400 barrels were recovered (16,800 gallons) and that approximately 350 barrels still remain in onsite soil at the site (14,700 gallons). Based upon a visual survey of oil impacted soil, conducted by Kleinfelder and Siegfried Engineering, Inc. the area of impacted soil was estimated to encompass approximately 2.2 acres, extending north, east, west, and south of the pipeline rupture location (See Plate 2). Please note the footprint area has since been revised (see Plate 4). Based upon aerial photo review of the spill area, it appears the largest amount of oil settled to the east and northeast of the rupture following the crop lines and surface topography. San Joaquin County Environmental Health Division (SJC/EHD) requested a workplan for the purpose of assessing the limits of contaminated soils and groundwater quality beneath the site. That workplan (File No. 42428 / ST04P118) was prepared by Kleinfelder, dated March 22, 2004 and was 'submitted to SJC/EHD for review and comment. This workplan was subsequently approved.by SJC/EHD. The following summarizes Kleinfelder's findings from implementation of that workplan. On May 19 and 20, 2004, a pushprobe soil and groundwater assessment was conducted. A total of twenty-nine (29) push probes were advanced during the field activities. A total of twenty two 4- point composite soil samples, 26 discrete soil samples and four groundwater samples were submitted for chemical analyses for purgeable and extractable petroleum hydrocarbons and benzene, toluene, ethylbenzene, and xylenes (BTE3) compounds. Twenty five (25) shallow probes were advanced to total depths ranging from approximately 8 to 24 feet bgs. Four deeper groundwater pushprobes were advanced to total depths ranging from 44 to 58 feet bgs. Groundwater was noted approximately 43 feet bgs in these four deeper borings. A summary of Kleinfelder's findings are summarized as follows: 1) Twelve discrete soil samples were collected and analyzed from perimeter pushprobe borings at depths ranging from 5 to 43 feet bgs. Based on this data, it is Kleinfelder's opinion that petroleum impacted soil has not migrated laterally a significant distance beyond the footprint area. Please note this finding does not include potential soil vapor migration of volatile compounds, since soil vapor sampling was not conducted as part of this assessment. 2) A total of four grab groundwater samples were collected, one in the footprint area-and three from perimeter locations. Relatively low concentrations of petroleum constituents were 44843.T04/ST04RI 121 r Page 2 of 9 Copyright 2004,Kleinfelder,Inc. September 2,2004