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URS Mr. Johnny Yoakum San Joaquin Environmental Health Department February 21,2012 Page 2 SCOPE OF WORK To determine the presence or absence of chemical impacts in the sensitive areas idenitifed in the Phase 1 ESA , URS proposes the following scope of work: • Up to nine soil borings will be advanced on the Property. The proposed soil borings will be located adjacent to the former USTs, OWS, and septic system as shown in Figure 2. • The soil borings will be advanced using direct-push drilling equipment(i.e., Geoprobe)and will be continuously sampled using direct push technology(DPT)sampling methodologies to a maximum depth of 25 feet below ground surface(bgs). Soil samples will be collected using a 1.5-inch diameter, 4-foot long stainless steel sampling probe that will be lined with disposable acetate liners. • At least one groundwater sample will be collected from each of the three site features. Groundwater is anticipated to be at approximately 25 feet bgs. • Borings will be abandoned in accordance with local regulations and patched with concrete or asphalt. SOIL SAMPLE SELECTION FOR CHEMICAL ANALYSIS Soil samples collected will be screened for volatile organic compounds (VOCs) with a MiniRAE 3000 photo-ionization detector (PID) equipped with a 10.6 eV lamp. The sample intervals with the highest PID reading or any odor or visual evidence of contamination will be selected for analysis. In the absence of detectable PID readings or other evidence, the sampling interval at the terminal depth of the boring or at the soil/water interface (if the boring extended below the water table) will be selected by the field geologist for analysis. Soil samples will be preserved for laboratory analysis by cutting off the appropriate depth interval from the liner and sealing the ends with Teflon® paper and caps. The sample containers will then be labeled and placed on ice in a cooler pending delivery to the analytical laboratory. Soil samples collected for headspace analysis will be placed into plastic bags and allowed to degas a minimum of 1/2 hour in a warm environment to reach volatile equilibrium. The groundwater sample will be collected by using 0.5-inch outside-diameter screen of Schedule 40 PVC. Additional five-foot PVC sections will be added to advance the screen to the desired sample depth. The groundwater will then be collected using a steel bailer and transferred to pre-cooled sample containers. Soil and groundwater samples collected from the former USTs will be analyzed for Total Petroleum Hydrocarbons (TPH)-gasoline range organics(GRO)by Method 826013, and TPH-diesel range organics