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conducted by a State-licensed (C57) drilling company. The CPT borings will be advanced to an estimated depth of approximately 90 feet. The borings will advanced using a direct CPT rig that will log soil lithology from approximately five feet bgs to the maximum depth explored. A groundwater sample will be collected from a separate borehole advanced adjacent to each of the CPT borings using a modified Hydropunch°sampler. Prior to groundwater sampling, a water level meter will be used to confirm that the drive rods do not contain water. The sampler will then be driven to approximately three feet below the desired sampling depth and then retracted three feet to expose the disposable Schedule 20 polyvinyl chloride (PVC) screen and allow groundwater to enter the Hydropunch® sampler. The water samples will be collected by lowering a 3/4-inch diameter stainless steel bailer through the drive rods to groundwater. The groundwater will be bailed from the drive rods and decanted into 40-milliliter glass vials. Following the collection of the samples, the drive rods will be retracted, leaving the disposable drive tip and four-foot length of PVC well screen in the hole. Following completion, the CPT borings will be grouted through the drive rods from the total depth explored to surface grade with neat cement. Groundwater Sample Analyses Groundwater samples collected from the borings will be submitted under chain-of-custody procedures to a State-certified laboratory. The groundwater samples will be analyzed for total petroleum hydrocarbons quantified as gasoline (TPHg) utilizing EPA Method 801513; and benzene, toluene, ethylbenzene, and xylenes (BTEX), methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), di-isopropyl ether (DIPE), tertiary amyl ether (TAME), tertiary butyl alcohol (TBA), 1,2-dichloroethane (1,2-DCA), 1,2-dibromoethane (EDB), and naphthalene utilizing EPA Method 8260B. On-site Soil Boring Advancement and Soil Vapor Probe Installation In order to evaluate site conditions with respect to Petroleum Vapor Intrusion to Indoor Air and Direct Contact and Outdoor Air Exposure criteria of the Policy, two soil borings are proposed to be advanced at the approximate locations shown on Figure 3. Soil samples will be collected from each of these three borings at depths of approximately 4.5, 6, 10, and 11 feet bgs and analyzed for TPHg, by EPA Method 801513, and BTEX and naphthalene by EPA Method 826013. Two additional shallow soil borings will be advanced to depths of six feet bgs to facilitate the collection of soil vapor samples near the existing building at the locations shown on Figure 3. These soil borings will be completed as soil vapor sampling probes using '/4" or '/8" tubing and a filter point. To protect the integrity of the soil vapor sampling probes, the end of the tubing extending to the ground surface will be capped and a watertight wellhead will be set in concrete over the probe. At least 48 hours after installation, each vapor probe will be purged and sampled according to current California Department of Toxic Substances Control (DTSC) soil vapor sampling guidelines using laboratory-supplied manifolds and stainless steel Summa canisters. Each vapor sample will be analyzed for volatile organic compounds including BTEX, naphthalene, and a leak detection compound by EPA Method TO-15. REPORT PREPARATION Upon completion of the field activities, a report will be prepared describing the field activities and laboratory analytical results and will include an assessment of the extent of the petroleum 5 1 P a g e