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A V 26 April 2011 AGE-NC Project No. 95-0104 Page 11 of 12 • TPH-g and BTEX compounds were not detected in soil samples collected from confirmation soil boring P-1, indicating that hydrocarbon impacted soil does not extend beyond the limits of the former UST area since SVE remediation was performed. • Over time 1,2-DCA-impacted ground water migrated northeast, the consistent ground water flow direction at the site, from the UST area toward and beyond MW-8, and then off-site in the area of wells MW-13 and MW-14. However, 1,2-DCA concentrations detected in wells MW-13 and MW-14 have been low (6.1 pgll and 34 pg/1)and were non-detect during the August 2010 sampling event. Currently,the lateral and vertical extent of 1,2-DCA-impacted ground water at the site is defined. • A domestic water well receptor is located approximately 250 feet northeast of the site in the down gradient direction at 4716 East Waterloo Road (DW-1). Between November 2008 and August 2010, five ground water sampling events were performed at DW-1; ground water samples were collected and analyzed for 1,2- DCA. 1,2-DCA was not detected above laboratory reporting limits during any of the sampling events (Table 3). Drinking water at and near the site is currently provided by the City of Stockton municipal wells. California Water Service Company (Cal Water) maintains a municipal well and tank approximately 2,000 feet north of the site between East Waterloo Road and Cherokee Road. No other municipal wells maintained by the City of Stockton or Cal Water are located within 2,000 feet of the site. • AGE concludes that petroleum hydrocarbons remaining beneath the site appear to pose minimal risk to human health and beneficial use of ground water down-gradient from the site. 8.0. RECOMMENDATIONS Based upon data collected from the site, AGE recommends the following: • No further subsurface investigation at this time. The SW IC site has adequately assessed and remediated petroleum-impacted soil and ground water associated with the UAR. • Consideration of the facility for closure and destruction of monitoring wells in accordance with applicable regulations as part of the site closure preparations. Advanced CeoEnvironmental,Inc.