SITE INFORMATION AND CORRESPONDENCE

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New West Petroleum • - 3 - • 26 November 2012 6437 Banner Street Lodi, San Joaquin County MW-12A, MW-13A and MW-13B) were installed between September 2007 and December 2007. The November 2007 Human Health Risk Assessment reviewed the soil vapor and monitoring data, and concluded risks from soil, soil vapor, and groundwater as a contributor to vapor migration into nearby buildings was insignificant. In September 2008, six additional offsite extraction wells (EW-6A, EW-7A, EW-713, EW-86, EW-9B, and EW-10A) were installed to ensure hydraulic control and to complete the plume capture. Groundwater extraction continued until April 2011, when the GWETS was shut off for rebound testing after extracting and treating 23,517,871 gallons of groundwater. Corrective action and interim remedial action removed 123.79 lbs. of MtBE from groundwater. Semi-annual groundwater monitoring continued until June 2011, when testing showed no significant rebound and a stable and declining groundwater plume that was no longer threatening sensitive receptors. Maximum MtBE concentrations in December 2010 and June 2011 are in ug/L in Table 1: Well MW-4A MW-7A MW-613 MW-8B MW-20A EW-86 EW-96 Date 12/10 12/10 12/10 12/10 12/10 6/11 6/11 MtBE 89 30 93 140 22 5.1 11 When it was determined and agreed by Regional Board staff that further remediation was not cost effective and rebound was not significant enough to resume remediation, General Permit R5-2008-0085 for the NPDES discharge was terminated by the Regional Board Executive Officer on 24 August 2011. Sensitive Receptor Survey Prior to 1997, a single SJC water supply well, located approximately 70 feet south of the Site, supplied water to Flag City. The SJC supply well was destroyed in 1996, when CSA 31-1 and CSA 31-2 were brought online. A sensitive receptor survey conducted by Flag City Chevron in 1997 identified five public supply wells within 2,500 feet of the site. Rocky's Restaurant (RDW-1), located 350 feet southwest of the site, became impacted by the Flag City Chevron MtBE release, and was properly destroyed in March 2002. The 3 B's Truck Stop supply well, located 450 feet west-southwest of the Site, became impacted with MTBE from their own release, and was reported as destroyed in 2011 CSA-31-2, at 700 feet south-southeast of the Site, is the nearest downgradient supply well, and has remained non-detect for petroleum hydrocarbons from 2005 to 2011. CSA 31-1, 1,600 feet to the southeast of the Site and next to the CSA-31 wastewater treatment plant, is currently inactive with no plan to bring it back online. CSA-31-3, a new public supply well (AKA Flying J Truck Stop supply well) is upgradient and approximately 1,100 feet to north of the Site, north of Highway 12 and the New West Petroleum site. According to the SJCEHD, CSA-31-3 is currently offline awaiting approval for operation of a nitrate treatment system. A commercial truck wash