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Limited Site Investigation Corral Hollow sho in center,Tracy,California photoionization detector[PID)), colors,odors encountered and visual observations of unusual conditions.A global positioning system (GPS) unit was used to survey sampling locations. Field Observations Soil generally consisted of loose, brown silty sand.Traces of clay and gravel were observed in the borings. Dark gray soil was observed in borings SB-1 and SB-2 at a depth of approximately 2.5 to 4 feet bgs. No staining or odors were observed during the collection of the soil samples. Headspace PID readings were not elevated (less than 5 parts per million)during the sampling activities. Borehole Abandonment and Investigation-Derived Waste The borings were abandoned by grouting in accordance with San Joaquin County boring permit requirements, under the observation of a County Inspector. Neat-cement grout was used to seal each hole from the bottom up,to approximately 0.5 foot bgs.The remainder of the boring was filled with concrete,which was dyed black,to match the existing pavement. One 55-gallon drum of soil cuttings was generated during the sampling activities.The drum was sealed, labeled and is being temporarily stored at the rear(on the north side)of the OSH store. Disposable personal protective equipment(PPE)and sampling equipment was placed in plastic bags and disposed in an onsite industrial dumpster,the contents of which are routinely disposed of in a municipal landfill. Analytical Results The soil samples were submitted to Curtis&Tompkins Laboratories,certified by the California Department of Health Services through Environmental Laboratory Accreditation Program.The samples were analyzed for the following: • TPHcr and TPHd using U.S. Environmental Protection Agency(EPA) Method 8015M • PAHs using EPA Method 8270-SIM TPHcr was detected at concentrations ranging from 8 milligrams per kilogram (mg/kg)to 630 mg/kg. TPHd was reported at concentrations ranging from 4.9 mg/kg to 220 mg/kg.The highest TPH concentrations were detected in sample SB-7-1-1.5, located in the central-eastern portion of the investigation area (Figure 2).TPH results were qualified by the lab because the detected compounds did not match the standard for a number of the results. However, based on examination of the chromatograms,the soil samples appear to contain a mixture of crude oil and diesel and are highly weathered.Analytical results are presented in Table 1. PAHs were reported in the three samples analyzed. Chrysene was detected in the samples at concentrations ranging from 9.6 micrograms per kilogram (ug/kg) and 33 ug/kg; pyrene was detected in samples SB-3-1-1.5 and SB-7-1-1.5 at concentrations of 8.4 ug/kg and 25 ug/kg, respectively. Sample SB-7-1-1.5 also had detections of fluoranthene(6.1 ug/kg), benzo(a)anthracene (14 ug/kg), and benzo(a)pyrene (5.5 ug/kg). Based on the results,samples collected from the 5.5-6 foot and 7.5-8 foot intervals are not recommended for analysis. Terraphase Engineering Inc. Page 3 of 5