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rh'9 KLEINFELDER on Plate 4. It is estimated that approximately 15 additional soil samples within the pipeline easement areas will be needed to evaluate residual petroleum concentrations 1 left in place in the pipeline easement area. The average depth of bottom soil samples is estimated at 5 feet in Area B (west and northwest portion of footprint area) and 9 feet in Area C (central area). Confirmation bottom soil samples are estimated at a depth of 13 feet bgs in Area D (eastern area). Kleinfelder proposes collection of approximately twenty four (24) sidewall samples around the perimeter of the estimated excavation boundaries at 40 to 60 foot intervals as shown on Plate 4. The interval variances are based partly on proximity to excavation bottom samples to the estimated sidewall locations. At this time Kleinfelder proposes the sidewall confirmation sampling depths to be approximately '/2 the estimated total removal depth of the obvious petroleum impacted soil as illustrated on Plate 4. Therefore, Kleinfelder proposes excavation sidewall soil sampling depth within Area B to average approximately 2 '/2 feet bgs, and the average sidewall sample depth of 4 1/2 feet bgs in Area C. The average sidewall soil sample depth in Area D is proposed at approximately 6 1/2 feet bgs. Previous soil sampling locations and analytical results from Kleinfelder's pushprobe assessment will be used to evaluate actual confirmation soil sampling locations and depths. A PID will be used during excavation activities as a screening tool to help assess the potential limits of petroleum impacted soil. The potential and actual confirmation soil sampling locations will be field screened using the PID and recorded for reporting purposes as generally described in Appendix B, Section B-2.2. The excavation contractor (Pacific States) will be responsible for excavating according to OSHA guidelines and according to PG&E and Chevron Pipeline specifications. Pacific States is not a subcontractor of Kleinfelder, they are contracted with Pegasus MH Ventures I. The soil samples from within the excavation will be collected from near the teeth within the bucket of an excavator or by using a stainless steel core barrel attached to extension rods and a slide hammer. The stainless steel tubes will be removed from the soil and the ends sealed with Teflon tape and tightly fitting plastic caps. The samples will be placed immediately into an iced cooler. The samples obtained will be transported under chain-of-custody control to Kleinfelder's office and then transported by courier in a chilled ice chest to a State-certified analytical laboratory for the requested chemical analyses. The stainless steel hand auger and sampling equipment and tubes will be cleaned between sample locations with a Liquinox® (laboratory-grade detergent) and potable water wash and a distilled water rinse. New stainless steel tubes used for sample collection will also be decontaminated using the same methodology. Based upon preliminary verbal conversation between RAH Environmental of Loomis, California (RAH), a hazardous materials excavation and disposal subcontractor, it is 44843.T04/STO5R1333/DH:Iv Page 8 of 17 ©2005 Kleinfelder, Inc. October 25,2005