SITE INFORMATION AND CORRESPONDENCE

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No.Further Action Required Determination _ 5_ Former Lyoth Loading Station 19 November 2009 • Lyoth Offsite two primary areas as discussed above: along the former pipeline and beneath a former storage tank. • Dermal contact is possible by future residents and maintenance/trench excavation workers within the area of affected soil on both sites. Based on the risk assessment findings, the concentrations of residual crude oil do not present an unacceptable health risk for future onsite adult or child resident and/or for construction/trench workers. Avoiding development of the known affected areas on the sites by future excavations could reduce/minimize potential human contact with residual TPH compounds. Summary: The TPHc compounds detected in soil and groundwater are highly immobile, limited in extent, and will continue to attenuate naturally with time. Based on results of the sites investigations and the findings in the 1999/2002 HRA evaluations and the 2009 ERE report findings, it is anticipated that the residual crude oil remaining in soil and groundwater would not present an unacceptable threat to human health for the adult/child resident or for the construction/trench worker scenario. Consistent with SWRCB Resolution No. 92-049, an evaluation of alternative cleanup technologies other than natural attenuation are ineffective, not easily implemented, and/or disproportionally costly in comparison to benefits. The six project groundwater monitoring wells were properly destroyed in October 2009. The site specific SMP acts as a management reference designating Chevron as the responsible party if any affected soil or groundwater confirmed to be related to the historical pipelines is encountered during future construction/utility maintenance work. A copy of the SMP was provided to the owners of property determined to overlie the areas of affected soil/groundwater. No comments were received during the 30-day public notice period.