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stantec ` • November 30,2009 Page 2 of 3 Reference: Soil Investigation Work Plan ❑ Underground Utility Location and Clearance: In accordance with Underground Service Alert (USA) guidelines, Stantec will mark the locations of the proposed soil borings in white paint and notify USA at least 48 hours prior to commencing drilling activities. In addition, Stantec will contract a private utility locator to confirm that proposed drilling locations are free of detectable subsurface utilities. Prior to the onset of drilling, all borings will be air-knifed to a minimum depth of 5 feet below ground surface(bgs). Task 2— Direct-Push Soil Borings The investigation will include the advancement of seven direct-push soil borings as shown in Figure 2. The soil borings will be conducted in the vicinity of the two in-ground hoists. Locations were also based on discussions with Mr. George Pagano of PG&E during the site visit on November 23, 2009. Soil Sampling Procedures Soil borings will be advanced by Woodward Drilling, a California C-57 licensed driller, using direct-push drilling equipment. Borehole sampling will be conducted under the supervision of a California Professional Geologist. Soil encountered in the borings will be visually classified by a Stantec geologist in accordance with the Unified Soil Classification System (USCS). All boring locations are in concrete and will be concrete cored. Mr. George Pagano stated that the concrete is believed to be 6-inches thick. After concrete coring, borings will be air-knifed to a depth of 5 feet below ground surface (bgs), to confirm the absence of shallow subsurface utilities or other obstructions. After confirming that cleared boreholes are free of utilities and any other obstructions, direct-push undisturbed soil cores will be collected from the surface to a depth of 15 feet below ground surface(bgs)or refusal. Soil cores will hydraulically driven in 2- or 4-foot cores with acetate sleeves. Samples will be separated from cores by cutting the desired depth interval from the acetate sleeve and then capped at both ends. Soil will be screened in the field using a photoionization detector (PID) for the presence of volatile organic compounds (VOCs). Laboratory Analysis It is anticipated that three soil samples will be collected from each of the borings at depths of approximately 5, 10, and 15 feet bgs. The number and depths of the actual sample locations will be determined in the field based on soil screening and visual observations The samples will be submitted under chain-of-custody protocol to Calscience Laboratories for analysis of Total Petroleum Hydrocarbons as hydraulic oil (TPH-ho) by EPA Method 8015 with silica-gel cleanup. Laboratory analysis will be performed with standard 5-day turnaround time (TAT). Task 3— Report Preoaration Following the completion of the soil boring activities, Stantec will submit a brief technical report describing the methods and findings of the investigation. The report will include tabulated chemical testing results, soil boring logs, a site plan illustrating the soil boring locations, and complete laboratory analytical reports and chain-of-custody records.