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Direct Push Borings The field activities will include the advancement of approximately 9 direct-push borings placed at the proposed locations shown on Figure 2. Because of the presence of the concrete pad at the fuel pump island,two boring locations will require coring prior to emplacement of the direct-push probe. Soil samples will be collected from the direct-push borings using a hydraulically driven soil sampler equipped with an acetate liner. Soil samples will be collected at the approximate depths of 0.3 in (1 foot), 1 in (3 feet) and 2 in(6 feet) from seven of the borings and from 0.3 in(1 foot) and 1 in (3 feet) from two of the borings (shallow borings). The soil depths may be adjusted according to the geophysical survey findings and existing site conditions. Four surface samples will also be collected. Approximately 29 samples will be retained for testing. Each soil sample will be secured with Teflon sheets, plastic end caps and tape; labeled; and placed in a chilled cooler pending delivery to the analytical laboratory. The soil samples will be delivered to Creek for chemical analyses under standard chain-of-custody procedures. The soil borings will be backfilled to the ground surface with a slurry of neat Portland cement. Geologic conditions observed in the borings will be recorded on the boring logs prepared under the direction of a California Certified Engineering Geologist (CEG) utilizing the Unified Soil Classification System. Descriptions of the soils recovered from the borings will be included in the Site Investigation Report. Quality assurance/quality control (QA/QC)procedures will be performed during the field exploration activities. These procedures will include decontamination of sampling equipment before each sample is collected; and providing chain-of-custody documentation for each soil sample submitted to the laboratory. The soil sampling equipment will be cleansed between each direct-push boring by washing the equipment with an Alconox solution followed by a double rinse with deionized water. Rinseate water and excess soil from the borings will be contained within 209-liter(55-gallon) drums and stored onsite pending laboratory analysis and subsequent removal to an appropriate disposal facility. The soil samples will be field screened with a photo-ionization detector(PID)to obtain a preliminary indication of potential hydrocarbon impacts in the subsurface soils. The headspace readings will be recorded in the field and presented on the boring logs included in the Site Investigation Report. Laboratory Analyses Selected soil samples will be analyzed under a standard ten-day laboratory turn-around time for the following: • TPHd and TPHmo by Environmental Protection Agency(EPA) Test Method 8015 Modified (all soil samples). • O&G by EPA Test Method 1664(all soil samples). • Soil pH by EPA Test Method 9045 (two soil samples). • Four surface soil samples will analyzed for Title 22 metals by elements scan using ICAP EPA Test Method 6010. Waste Extraction Test (WET) will be performed using EPA Test Method 7000 on one sample if the elements exceed ten times their respective soluble threshold limit concentrations(STLC). Project No.S8475-06-70 -3- April 30,2003