SITE INFORMATION AND CORRESPONDENCE

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Chevron August 22, 1996 Chevron Michael J. Infurna Jr. Chevron Pipe Line Company 4000 Executive Parkway,Suite 400 San Joaquin County Public Health Services San Ramon,CA 94583 Environmental Health Division P.O.Box 5059 P.O. Box 388 San Ramon,CA 94583-0959 Stockton, California 95201-0388 Sousa Property (APN 238-080-01) Lammers &Byron Road, Tracy, California Dear Mr. Infurna: Chevron Pipe Line Company (CPL) would like to confirm with the San Joaquin County Public Health Services Environmental Health Division (SJC-EHD) that no environmental investigations, remediation, or other efforts are required to be conducted by CPL on the Sousa Property, located at the intersection of Lammers and Byron Road,Tracy California. The property is located south (across Byron Road) of the Dividend Property, where CPL's has conducted environmental investigations in the past and is currently negotiating closure with the Central Valley regional Water Quality Control Board (CVRWQCB). Previous work at the subject site was conducted by Mill Creek Associates (MCA) on behalf of other parties. Please reference the attached MCA letter to the SJC-EHD dated February 16, 1995. This work was also transmitted to the CVRWQCB in Mill Creek Associates letter dated February 13, 1996 (attached). Outlined below is a summary of this work and the rational for concluding that CPL operations, or operations of their predecessors, have not impacted the subject property: • The subject property is at approximately 1000 feet south of the Dividend Property and is not adjacent to CPL'S pipeline right of way, which runs parallel to Byron Road (MCA Site Plan; Figure 1). • The groundwater gradient, as shown in MCA groundwater gradient map (Figure 2), is to the north, thus placing the subject property up-gradient to any potential CPL sources. Recent groundwater sampling at the Dividend Property confirms a northerly gradient for the area. • Only one soil sample exhibited detectable concentration of hydrocarbons (Sample MW-3-1 at 60 mg/kg) using EPA Test Method 418.1; a screening method that is non-analyte specific and subject to many positive interferences from non-petroleum sources. Laboratory analysis of soil samples using more specific methods (EPA Test Method 8015 modified for gasoline, diesel, and kerosene) exhibited non-detectable concentrations of petroleum hydrocarbons. • The lack of detectable levels of petroleum hydrocarbons in the groundwater. • All soil and groundwater samples exhibited non-detectable levels of benzene,toluene, ethlybenzene, and xylenes.