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Subsurface Investigation Scope Prior to commencement of subsurface investigation activities, public utility locate services would be notified so that underground utilities can be located prior to the start of work. At the time of the site investigation, prior to the start of work, an on-site health and safety plan will be completed and signed by the on-site consultant and drillers (attached to this work plan). The proposed subsurface investigation would include up to eight direct push borings to collect subsurface soil samples within areas adjacent to trench drains,hoist/lifts, car wash sump, former and possible current locations of a spray-paint booth, and hazardous waste storage areas. The various borings would be advanced to depths ranging between up to approximately 30 feet below ground surface (bgs)depending on the location on the property. Continuous soil sampling would be performed on all borings, the soils identified and logged, and the soil cores reviewed for indications of contamination. At least one soil sample would be collected from each boring within areas of suspected impact or, if no indications of impact were observed, at a shallow point in the boring as well as at the deepest portion of the boring. If groundwater is encountered during drilling activities, a temporary screen will be set and a well-point groundwater sample will be obtained. Soil samples and/or groundwater samples would be analyzed for Volatile Organic Compounds (VOCs), Total Petroleum Hydrocarbons-Diesel Range Organics (TPH-DRO), Total Petroleum Hydrocarbons-Gasoline Range Organics (TPH-GRO), heavy metals (RCRA 8 Metals); and/or organochlorine pesticides. The Environmental Protection Agency analytical methods that may be used in this investigation are included as Attachment 1. A site plan with the approximate locations of the proposed borings is shown in Attachment 2. Boring locations may be modified based on site conditions and/or locations of existing utilities. A summary report of the investigation and analytical results would be prepared upon the completion of the field activities and receipt of the laboratory analytical report. Investigation Methods Direct push activities would be performed by Cascade Drilling, a California licensed driller — License Number C-57 938110,using a direct push drilling rig. Soil sampling would be accomplished using a two- inch diameter, four- or five-foot long, hollow stainless steel sampling tube lined with acetate sample liners advanced on stainless steel push rods. Each boring would be backfilled and cemented with a cement grout mixture consisting of approximately 95% Portland Cement and 5% Bentonite with the surface restored using a concrete or asphalt patch. All non-disposable sampling equipment would be steam cleaned or power washed in between each boring and at the end of the sampling event. Soil spoils and cuttings as well as decontamination water would be collected and stored in a separate lidded bucket or 55-gallon drum, depending on the amount of material, and the container labeled with a"non-classified waste material' label containing information on material, site name and address, generation date, and generator and contractor contact information. A copy of this label is attached to this work plan. Waste soil and decontamination water would remain on the site until receipt of the laboratory analyses when the appropriate disposal method, such as landfill, etc., can be determined. Sample Collection Methods Soil and/or groundwater samples will be collected in new, specially cleaned containers provided by the analytical laboratory and specific to the analysis to be performed. If appropriate for the analysis, each sample container will be filled completely so that no headspace is present in the containers. Sample containers will be labeled with the site name, samples designation, and date and time of collection and placed in a rigid cooler and chilled to approximately four degrees Celsius for transport to the analytical Work Plan for Limited Subsurface Environmental Sampling 221,226, 229,251, &270 Oak Street 2 "FluclManteca, California 95337 .G. ... .