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JJW proposes to collect soil vapor from 6 locations at a depth of 5 feet below the surface. The locations will be at the former UST locations (figure 2). It is anticipated that all of the locations will be on the JC Trucking property, The exact locations will be determined in the field after locating Underground utilities and depending on accessibility. All soil vapor sampling and analytical processes will follow the California Department of Toxics Substances Control / Los Angeles Regional Water Quality Control Board (DISC/LAWQCB) "29 January 2003 Advisory -- Active Soil Gas Investigations" protocols (DTSC protocols). The soil vapor samples will be collected using a direct push sampling rig such as a Strataprobe by a subcontract that is expertly familiar with the DTSC protocols. Probe rods will be hydraulically driven or hammered into the subsurface to the sampling depth and then withdrawn slightly to open the sampling port at the probe tip. Each probe rod has an internal, inert, low dead volume, disposable tubing that transfers the soil vapor sample from the probe tip to the surface for sampling. The internal tubing is replaced after each vapor sample. Following DTSC protocols, the subcontractor will wait a minimum of 20 minutes after probe emplacement for equilibration, and sample the vapor probe location using an inert, disposable syringe or a clean glass syringe. While the sample is being drawn, a leak check compound will be applied around the probe rod, ground-surface interface, and exposed sample tubing as per DTSC protocols. Additionally, the first sample location will be placed at the expected location of highest contamination and a purge volume test performed as outline in the DTSC protocols. Once sampled, the sample syringe will be transferred to an on-site mobile analytical laboratory familiar with the DTSC protocols and analyzed within a few minutes. Since TPH-gasoline, BTEX components, MtBE, and lead scavengers are the volatile compounds that have been noted previously at the subject site, and are common compounds of concern for vapor intrusion, the soil vapor samples will be analyzed for the following parameters: -- Total petroleum hydrocarbons as gasoline (TPH-gasoline) (EPA method 8260); -- The aromatic volatile fuel components benzene, toluene, ethylbenzene, and xylenes (BTEX) (EPA method 8260); -- Fuel oxygenate methyl-t-butyl ether (MtBE) (EPA method 82606); -- The lead scavengers 1,2 dichloroethane (1,2 DCA) & 1,2-dibromoethane (EDB) (EPA method 8260). The mobile analytical laboratory will have sufficiently low reporting limits as will be required for input into the DTSC version of the Johnson & Ettinger Soil Gas Screening Model as per the VI document. Following completion of the on-site investigation and vapor intrusion risk modeling, the activities and findings of the vapor intrusion site assessment will be summarized in the subsequent semi-annual groundwater monitoring report. JJW GEOSCIENCES Inc.