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sow, %%owl INTRODUCTION r This workplan presents a proposed soil investigation at two fuel dispensers at the Pacific Gas and Electric Company(PG&E) Stockton Service Center. The service center is located at 4040 West Lane in Stockton, California (Figure 1). Three dispensers are located south of the Fleet Services Building (Figure 2): two unleaded gasoline dispensers (UNL1 and UNI-2) on a fuel island located about 20 feet south of the Fleet Services Building; and one diesel dispenser on a fuel island located about 50 feet from the building (Figure 3). The purpose of the proposed investigation is to assess the extent of hydrocarbons in soil in the vicinity of the diesel dispenser and gasoline dispenser UNI-11 based upon the results of an October 2003 investigation. BACKGROUND In October 2003, the three fuel dispensers were upgraded with under dispenser containment(UDC). Additionally, the waste oil tank (WOT) original double-walled piping was replaced with enhanced double-walled piping (Figure 3). This work was performed by Paradiso Mechanical, Inc. (San Leandro, CA) in order to comply with State Water Resources Control Board Underground Storage Tank Regulations Title 23 Division 3 Chapter 16 CCR SB 989. Three years earlier, in December 2000, new dispensers were installed. Impacted soils were excavated and removed from around UNI-2 and the diesel dispenser. Approximately three cubic yards of soil was removed from around UNI-2 and 22 yards were removed from around the diesel dispenser(IT Corp, 2001). Figure 4 shows the outlines of those excavations During the 2003 dispenser and piping upgrade, Geo-Logic(Crockett, CA) collected five soil samples from the excavations: one sample was collected from just beneath each of the three dispensers and two samples were collected along the WOT piping (Figure 4). The samples were collected at depths of 4 to 4.5 feet. Geo-Logic did not observe any evidence of hydrocarbon contamination at any of the three dispenser soil sample locations except at UNL1, where there was a slight hydrocarbon odor at two feet below ground surface (bgs), but no odor at the sample depth of four feet. Geo-Logic did not observe any evidence of ` ~ hydrocarbon contamination in the WOT piping trench, including the two WOT soil sample locations. Ms. Michelle Le of the San Joaquin County Environmental Health Department(EHD)witnessed the sampling. The dispenser soil samples were chemically analyzed for diesel; gasoline; benzene, toluene, ethylbenzene and xylenes (BTEX); and MTBE. The UNL1 and UNI-2 samples were additionally analyzed for four other fuel oxygenates. The WOT piping soil samples were chemically analyzed for LUFT 5 metals (cadmium, chromium, lead, nickel, and zinc) and volatile organic compounds (VOCs). Results of the sampling and analysis are presented in a report prepared by Geo-Logic (Appendix A). Following the upgrades, the excavations were backfilled with clean imported fill, and the surface concrete was repaired. 402.331-04.10.doc 1