SITE INFORMATION AND CORRESPONDENCE

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No Further Action Required Determination -2 - 19 November 2009 Former Lyoth Loading Station Lyoth Offsite consistent with the previous results of no unacceptable risk for future residents. OEHHA approved the HRA stating that..."risk between 10-6 and 10-4 are within the range of risk management, wherein other factors, along with risks, may be used to evaluate the acceptability of the risk." In January 2009, Chevron's consultant - Science Applications International Corporation (SAIC) submitted an Environmental Risk Evaluation (ERE) for the Lyoth Offsite property that considered the potential risk to human health and the environment. According to the findings, the potential exposure pathway is incomplete and thus no risk for future site residents or site workers. Direct exposure to petroleum chemicals of potential concern by future construction/trench workers at the site were compared to applicable environmental screening levels. According to the findings, the analytical results reported are less than respective screening levels and thus, exposure to petroleum chemicals of potential concern does not pose a threat to future construction/trench workers. Additionally, according to the ERE report, threatened, endangered, or sensitive species do not occur within a one-mile radius of the sites. Consistent with State Water Resources Control Board (SWRCB) Resolution No. 92-049, Section III, A through C, SAIC evaluated alternative cleanup technologies and found that any process other than natural attenuation would be ineffective, infeasible, and disproportionally costly. Residual crude oil concentrations naturally degrade with time. Issues: In the early 1990's, a release of non-hazardous crude oil and/or fuel oil to soil and groundwater was discovered from the historical OVP and/or petroleum product storage vessels present at the former Lyoth loading facility. The historical OVP and the former facility were utilized by Chevron predecessors to transport crude oil from Kern County to San Francisco Bay area refineries from the 1900's to the 1970's. The former facility was used to transfer fuel oil received from the Bay area refineries to locomotives, rail cars, and/or trucks. Soil impacts consist primarily of total petroleum hydrocarbons as crude oil (TPHc) which may contain polynuclear aromatic hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BTEX). Soil and groundwater affected by petroleum hydrocarbons as crude oil has been delineated. Setting: Primarily rural agricultural with residences; light industrial facilities to the north and the U.S. Department of Defense Tracy Depot facility is adjacent north-northwest of the former facility. Source: Historical leaks from crude oil pipeline(s) and/or storage tanks installed in the early 1900's, and removed from service during the late 1960's to early 1970's. The former facility petroleum storage tanks and associated piping and pumps have been removed. Actions: Preliminary investigations were conducted between the early 1990's and 2008. Between 1990 and 1998, 50 exploratory soil borings were advanced to approximate depths ranging from 10 to 37 feet bgs and seven of the borings were converted to groundwater monitoring wells. Depth to groundwater ranges between approximately