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`' 15 June 2009 Nfte AGE-NC ProjectNo.05-1306 Page 26 of 33 removed impacted soils, this exposure pathway is assumed to be resolved. Residual petroleum impacts do remain;however impacts are relegated to saturated soils and are generally considered to be a low level residual ground water issue. 8.3. GROUND WATER EXPOSURE PATHWAYS There are three exposure routes,ground water ingestion, dermal contact,and volatilization that are associated with ground water. Ground water at the site is not utilized for any purpose as the municipal water supply is available. As discussed in Section 2.3, the City of Stockton municipal wells are not at risk of exposure. Currently the Facility and surrounding properties obtain potable water from the City of Stockton. This Facility is expected to remain connected to the city water system. According to the water well survey completed for this site in 2000 (ATC)indicated that the nearest I`. well potentially used for drinking water is a domestic well located approximately 1,300 feet to the south of the site. California Water Service Well #70, located at Navy Drive and Charter Way, is approximately 2,800 feet southeast of the site. Due to the distance of these wells from the elevator �- and plume stability, there are no ground water receptors that have been identified. Additional, the San Joaquin county EHD well code has placed a deep grout seal requirement(100-200 feet)for areas surrounding major sources of dissolved contamination(McCormick and Baxter site);this restriction would excluded the ground water from site being utilized a domestic source of ground water. 8.4. VAPOR INTRUSION The ground water depth at the former Continental Grain Company Facility varies from 5 feet (off site to the south at MW-5 and MW-6)to 12 feet below surface(on site)depending on location. The potential for vapor intrusion of volatile contaminants from the ground water into buildings on site or off site is an exposure pathway that was considered. Structures were evaluated both off-site and on-site and their distance from the residual impacts in the former UST location. Shallow impacted soil was remediated and clean, fine grained soil was replaced into the of the excavation area. There are no structures either on or off-site that are within the footprint of the documented petroleum plume associated with this site when considering both current and historical data. The nearest 1., structures include a residential area approximately 100 feet south of MW-5 and MW-6 and grain storage facilities approximately 200 feet northwest of MW-1. This pathway is not complete due to the characteristics of the residual material in the ground water. Advanced GeoEnvironmental,Inc. 1.r