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ARS„ Prior to initiating drilling activities, a site-specific Health and Safety Plan (HASP) was prepared, and a tailgate safety meeting was conducted with all site workers. 3.2 Location of Borings Soil boring locations are shown on Figure 2 and Figure 3. The four borings, B-1 through B-4, were arrayed from northwest to southeast on the northeast corner of the property, in an expected downgradient (northeast) direction from the possible location of the former Site gas station. 3.3 Drilling and Sampling of Soil Borings The four investigative soil borings (B-1 through B-4) were drilled by Gregg Drilling of Martinez, California. The borings were drilled to approximately 30 feet in depth using direct- push hydraulically-driven soil coring equipment. For each boring, continuous four-foot soil cores were collected to total depth in a clear plastic acetate tube, nested inside a stainless steel core barrel. After each four-foot core barrel was brought to the surface and exposed, the core was sliced lengthwise to expose the soil core, examined, logged, and field screened for hydrocarbons by a qualified scientist using sight, smell, and an organic vapor monitor (OVM). All coring and sampling equipment was thoroughly cleaned and decontaminated between each sample collection by triple rinsing first with water, then with dilute tri-sodium phosphate solution, and finally with distilled water. Cleaning rinseate was contained onsite in a sealed drum pending laboratory results. Subsurface soils were sampled at approximately five-foot intervals starting at about ten feet in depth. After the sample and core barrel were raised to the surface, each sample was collected as follows: (1) The filled acetate tube was exposed for visual examination; (2) The selected sample interval was collected by cutting the sample and acetate plastic tubing to the desired length (typically about six inches); (3) The ends of the selected sample were quickly wrapped with Teflon sheets or aluminum foil, capped with plastic end caps, labeled and wrapped tightly with tape; and (4) The sealed soil sample was labeled and immediately placed in cold storage for transport to the analytical laboratory under formal chain-of-custody. Following completion of all sampling activities, the investigative borings were grouted to match existing grade using a cement\sand slurry. Soil cuttings generated during this investigation were stored onsite in sealed DOT-approved containers. 3.4 Laboratory Analysis of Soil and Groundwater Samples A total of 14 soil samples from the four borings were analyzed for the following parameters: USEPA 8260B Total Petroleum Hydrocarbons as Gasoline Range Organics (TPH-G) USEPA 8260B Benzene, Toluene, Ethylbenzene, Xylenes (BTEX) USEPA 8260B Oxygenates (TBA, MTBE, DIPE, ETBE, and TAME) PHASE II ENVIRONMENTAL SITE ASSESSMENT Page 4 3310 & 3330 E. MAIN ST., STOCKTON, CA