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Stantec April 24, 2009 Ms. Kristi Shelton Drilling and Soil Sampling Direct-push soil borings will be advanced by Environmental Control Associates, Inc., and directed by a Stantec geologist. Soil borings will be cored continuously to approximately 20 feet bgs, and screened for the presence of volatile organic compounds using a photoionization detector. Up to three soil samples from each soil boring will be retained and analyzed for total petroleum hydrocarbons as gasoline, diesel, and motor oil using Environmental Protection Agency (EPA) Methods 8260B and 8015M. The two soil samples reporting the highest concentrations of petroleum hydrocarbons will be analyzed for CAM 17 metals by EPA Methods 6010/7470 for waste characterization purposes. Waste Management and Reporting Following completion of each soil boring to total depth, the boreholes will be backfilled with neat cement grout. Soil cuttings will be stored on-site in steel 55-gallon drums pending analysis and disposal. Following receipt of analytical results, soil chemical data will be transmitted to Board staff via electronic mail. Any substantial changes to the proposed remediation strategy based on the findings of the subsurface investigation will be transmitted to the Board in a brief letter report. REMEDIATION ACTIVITIES This section includes a description of the planned removal activities at the Site. Primary tasks associated with the excavation and removal of soils are described below and include the following: permitting, traffic control, site security, safety monitoring and controls, removal and disposal of impacted soils, and site restoration. Area of Remediation Stantec proposes excavating up to 146 tons of impacted soils, corresponding to an excavation approximately 15 feet by 15 feet by 11 feet deep centered on well MW-1. The proposed extent of excavation, pending review of the soil chemical results obtained during the pre-excavation soil investigation, is illustrated on Figure 3. Excavation will be performed by Engineering/Remediation Resources Group (ERRG) under supervision of a Stantec geologist. Site Preparation and Notifications The site is currently unoccupied. The area of proposed excavation area is surfaced with dirt and a small section of asphalt which forms an adjacent driveway. Prior to excavation, the asphalt will be removed using a backhoe or similar equipment and off-hauled to a recycling facility. Prior to excavation activities, Stantec will mark the work area in white paint, and notify Underground Service Alert at least five days before digging. Stantec has identified and mapped the on-site utilities during previous site work; however, Stantec will subcontract with a private utility locator to confirm the absence of underground utilities in the work area. Stantec will notify Board staff approximately five days before beginning excavation. Stantec will also provide pre-project notification to the San Joaquin Valley Air Pollution Control District in accordance with agency regulations. Based on the size of the proposed excavation, no grading permit is required from San Joaquin County. PG&E will notify the adjacent property owner of the pending work.