SITE INFORMATION AND CORRESPONDENCE

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• t" L 9 2,1Pacific Car Wash 111% 4- - December 2013 Claim No4405 lfi12325ue, Stocktond ° � td+l , w is provided to water users near the Site by the Stockton East Water Department and the California Water Service. The affected groundwater is not currently being used as a source of drinking water, and it is highly unlikely that the affected groundwater will be used as a source of drinking water in the foreseeable future. Other designated beneficial uses of impacted groundwater are not threatened, and it is highly unlikely that they will be, considering these factors in the context of the site setting. Remaining petroleum hydrocarbon constituents are limited and stable, and concentrations are decreasing. Corrective actions have been implemented and additional corrective actions are not necessary. Any remaining petroleum hydrocarbon constituents do not pose a significant risk to human health, safety or the environment. Rationale for Closure under the Policy • General Criteria: The case meets all eight Policy general criteria. • Groundwater Specific Criteria: The case meets Policy Criterion 1 by Class 4. The contaminant plume that exceeds water quality objectives is less than 1,000 feet in length. There is no free product. The nearest water supply well or surface water body is greater Ph �zSo' than-106 et from the defined plume boundary. The dissolved concentrations of benzene and methyl tert-butyl ether (MTBE) are each less than 1,000 pg/L. • Vapor Intrusion to Indoor Air: The case meets the Policy Exclusion for Active Station. Soil vapor evaluation is not required because the Site is an active commercial petroleum fueling facility and the release characteristics do not pose an unacceptable health?Kk.� • Direct Contact and Outdoor Air Exposure: Although no document titled 'Risk Assessment" was found in the files reviewed, a professional assessment of site-specific risk from exposure through the direct exposure pathway was performed by Fund staff. The assessment of site-specific risk from potential exposure to residual soil contamination found that maximum concentrations of petroleum constituents remaining in soil will have no significant risk of adversely affecting human health. The Site is paved and accidental exposure to site soils is prevented. As an active petroleum fueling facility, any construction worker working at the Site will be prepared for exposure in their normal daily work. Objections to Closure and Responses The County, on the Path to Closure page in GeoTracker, opposes closure because: • Secondary source remains. RESPONSE: Secondary source as defined by the Policy has been removed by soil vapor extraction. The soil vapor extraction system when last monitored (October 7, 2013) was removing vapors at a rate of 3.1 pounds of TPHg extracted per day. The remediation system has reached the engineering and practical limits of the system design. • Case does not meet groundwater pathway in Policy. RESPONSE: The case meets Policy Criterion 1 by Class 4. The contaminant plume that exceeds water quality objectives is less than 1,000 feet in length. There is no free product. The nearest water supply well or surface water body is greater tha 1,000 feet from the defined plume boundary. The dissolved concentrations of benzene MTBE are each less than 1,000 pg/L. 1111110 Determination The Fund Manager has notified the tank owners or operators and reviewed the case history of their tank case. The Fund Manager determines that closure of the tank case is appropriate based upon that review. The Fund Manager has prepared this review summary report summarizing the reasons for this determination, provided the Review Summary Report to the applicable regional Page 2 of 14