SITE INFORMATION AND CORRESPONDENCE

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Soil and Groundwater Management Plan Former Lyoth Loading Station June 2,2009 the region varies from 5 to 15 feet bgs,with a historical flow direction slightly variable from northeast to northwest at an average gradient of approximately 0.003 feet per foot. Previous investigations indicate that soils encountered at the Site are a mixture of fine-grained unconsolidated sediments, consisting mainly of clays and sands. 2.2 ENVIRONMENTAL BACKGROUND Site investigations were performed between 1990 and 2007, during which time a total of 43 soil borings were advanced at the Site, and a total of seven groundwater monitoring wells were installed (one destroyed in 2001). The extent of affected soil and groundwater was defined during the course of these investigations. A map depicting sampling locations of the investigations and the extent of affected soil and groundwater are shown on Figure 2. CEMC commissioned a human health risk assessment in 1999. The risk assessment was performed relative to assumed future residential land use. Results of the risk assessment indicated that the presence of the hydrocarbon constituents in the subsurface do not pose an unacceptable risk to future residents at the Site. Further evaluation was performed through 2007. This included groundwater monitoring activities. SAIC recommended no further action at this Site in April 2008. The RWQCB requested further development of human health risk scenarios for commercial and construction worker scenarios for the affected properties. These were completed and submitted, and indicated that presence of the hydrocarbon constituents in the subsurface do not pose an unacceptable risk to commercial or construction workers at the Site. 3. ROLES AND RESPONSIBILITIES The roles and responsibilities of CEMC and the property owners are outlined in sections 3.1 and 3.2. If affected soil and groundwater associated with former HPP-BTR pipeline operations are encountered and a CEMC-authorized representative is not on Site, CEMC should be notified as early as possible so that consultation can be provided on the eventual disposal or reuse of affected soil, and discharge or disposal of affected groundwater. CEMC is not responsible for releases not associated with former HPP-BTR pipeline operations. 3.1 CHEVRON ENVIRONMENTAL MANAGEMENT COMPANY If affected soil and groundwater associated with former HPP-BTR pipeline operations are encountered during excavation or dewatering activities, CEMC will arrange for an environmental consultant to collect samples of the excavated material for profiling purposes. Once profiled, if the material is determined to be affected by former HPP-BTR operations and cannot be reused as backfill based on the presence of petroleum hydrocarbons, CEMC will arrange for the removal, transportation, and off-site disposal of the affected material by a qualified waste contractor to the extent required by the RWQCB. CEMC will also be responsible for public relations and regulatory issues that may arise during the project in response to the presence of affected soil and groundwater. CEMC will obtain any groundwater-discharge or air-emissions permits that may be required by the appropriate agency or agencies. 3.2 MR. RONALD E. HOFFMAN,ET AL. OR CURRENT PROPERTY OWNERS Mr. Ronald E. Hoffman, et al. or current property owners (property owners) will be responsible for notifying CEMC of upcoming work at the Site if possible, or for notifying CEMC as soon as Chevron 2 a 1W