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3.1 FIELD PREPARATION Prior to beginning the field program, ETIC will arrange for access with the current Site owner, Mr. Overton. Once site access has been arranged, the proposed boring locations will be marked and checked for the presence of underground utilities by Underground Service Alert. A private utility-locating contractor will also be hired to identify the presence of underground utilities. Drilling permits will be obtained from San Joaquin County Environmental Health Department (SJCEHD). A health and safety plan will be prepared and implemented during drilling and sampling activities. Each soil boring on the Site will be hand augured to a minimum depth of 4 feet BGS to identify utilities prior to drilling. 3.2 DRILLING AND SOIL SAMPLING Based upon hydrogeologic information obtained from other sites in the vicinity, groundwater in the shallowest aquifer flows to the southeast. The results of previous soil and groundwater investigations performed at the Site indicate that additional characterization of the extent of contamination is needed within the area of, east, and south of the former UST excavation, in the vicinity of the former dispenser, and in the area of a sump located inside the existing warehouse. Soil and shallow groundwater samples will be collected from I I borings to further characterize petroleum hydrocarbon contamination in these areas. The proposed boring locations are shown on Figure 4. Drilling will be performed by a C57-licensed contractor, using a direct-push drilling rig. All drilling equipment and sampling tools will be decontaminated prior to beginning the field program. Reusable sampling equipment will be thoroughly washed with a Liqui-Nox solution, rinsed with tap water, and then rinsed with distilled water prior to each use. An ETIC geologist will supervise all drilling and sampling activities. Soil samples will be examined for lithologic identification and visible signs of contamination in accordance with the Unified Soil Classification System and the Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), American Society for Testing and Materials (ASTM) Designation D2488 (ASTM 2000), and the observations will be recorded in the field logs. Technical guidance for the program will be provided by a California Professional Geologist. A photo-ionization detector (PID) will be used to monitor for organic vapors. Measurements of headspace vapors from soil samples will be recorded on the boring logs. If any unusual stains or odors are evident in the soil, additional samples will be collected for laboratory analyses. Each soil boring will be drilled to a total depth of approximately 55 feet BGS. Soil samples will be collected from the I I borings at approximate 5-foot intervals, at changes in lithology, at the soil-water interface, and where contamination is evident. The samples will be submitted for laboratory analyses. Additional soil samples may be collected and held for subsequent analysis, 7