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Soil Excavation Report J B Terminal/Blincoe Trucking 6700 Grantlme Road, Tracy, CA Project No W0322 01 Page 2 groundwater levels rose into the petroleum hydrocarbon contaminated soils left in place contaminants were released into the groundwater and higher levels were detected in well MW 1 Additionally, in the summer and fall of 1992 petroleum hydrocarbons impacted downgradient wells MW2 and MW4 (On July 30, 1992 and October 15, 1992 petroleum hydrocarbon analytes were detected in wells MW2 and MW4, respectively ) Water elevation data is summarized on Table 3 Based upon the fact that petroleum hydrocarbon contaminated soils left in place were introducing slugs of contaminants to the groundwater during the irrigation season RESNA Industries, on behalf of our client, recommended the removal of the impacted soil SCOPE OF WORK The following scope of work was based upon the information outlined above The work scope was designed to remove impacted soil in the vicinity of the former tank and product lines (Figure 2) All field work was performed under the supervision of RESNA personnel in accordance with the Site Safety Plan (Attachment 1) . Soil Excavation and Sampling To prevent residual petroleum hydrocarbon contaminants in the soil from acting as a source of degradation to the groundwater, the soil in the vicinity of the former storage tank and product lines was excavated Excavation took place on March 11 through 16, 1993 Depth to groundwater is approximately 12 feet below grade at this time of year therefore the total depth of excavation was less than 12 feet A backhoe capable of excavating to 15 feet below grade was used for excavation Excavation proceeded until field evidence (PID readings, odor, discoloration) indicated all contaminated soil had been removed Approximately 200 cubic yards of soil were excavated Clean overburden was separated from contaminated soil prior to stockpiling on site Petroleum impacted soil was underlain and covered with plastic sheeting A Photoionization Detector (PID) was used during excavation to assist in evaluating the lateral extent of soil impaction Figure 2 depicts the soil stockpile locations Following excavation five confirmation sidewall samples were collected from the excavation The exact number and locations of the samples was determined in the field by the geologist supervising the excavation, in cooperation with San Joaquin County Environmental Health Division (Figure 2) All verification soil samples were collected from the backhoe bucket at least three inches below the surface of the soil The samples were collected in prewashed brass liners Each liner was • sealed with a Teflon sheet and plastic caps, sealed in air-tight bags, and preserved on ice pending shipment to RESNA Environmental Laboratory, certificate #1211 R-32693 FNL