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laboratory lower detection limits for the fuel oxygenants MtBE, TAME, ETBE, DIPE, and TBA. MWI1 contained 30 ug/L MtBE MW11 is cross gradient and north of the site and of the TPHg plume This MtBE is highly suspect and does not seem to be associated with the R603 TPH9 plume Review of Table 1 shows that confirmed MtBE was first detected in MW8 and MW11 to 1997 with the first occurrence found at MW 11, March 1997 at 20 ug/L, see Figure l 1 A- In 1998 wells MW10, MW11, MW12 and MW13 contained MtBE with MW12 containing 33 ug/L, see Figure l l B In 1999 only MW12 contained MtBE at 16 ug/L, see Figure 11C The last sampling showed only MW11 to contain MTBE at 38 ug/L, see Figure 1 ID File review of the Canepa's Car Wash site, located at 6230 Pacific Avenue, shows that this site has MtBE associated with the groundwater TPHg plume The Chevron site located on the southwest corner of the intersection of Pacific Avenue and Benjamin Holt has a TPHg groundwater plume, but the file has not been reviewed by WEGE to ascertain if MtBE is associated with their plume, see Figure 2 Current Conditions of Site Since CRWQCB-CVR review dated July 17, 2000, all product dispensing piping and the three 10,000 gallon capacity double walled USTs have been removed and documentation sampling occurred See Update Status Report #56. On November 3, 2000 soil samples were obtained from native soil beneath each end of the removed USTs Ms Letitia Briggs of the San Joaquin County Environmental Health Department (SJC-EHD) was present to observe the sampling activities. : Native soils beneath the USTs were sampled using the direct push continuous core method. All sample results were below laboratory lower detection limits for TPHg, BTEX using EPA method 5030, modified 8015, and 8020, for Oxygenated Volatile Organics- Di-isopropyl Ether, Ethyl tert- Butyl Ether, Methyl-tert-Butyl Ether, tert-Amyl Methyl Ether and tert-Butanl using EPA method 8260 modified and for Ethylene Dibromide (1,2-Dibromoethane) and 1,2-D;chloroethane (1,2- DCA) using EPA method 8260 On February 23, 2000, the product dispensing piping was exposed and it was determined that this piping would be removed. The piping (double walled fiberglass) was removed and samples were obtained under the observation of Mr Michael Kith SJC-EHD One area of release was discovered beneath part of the piping and that area was later over- excavated During the removal of the double walled fiberglass product dispensing piping old abandoned steel product dispensing piping and vapor return piping was discovered This piping was inspected, removed and representative soil samples were obtained, under the observation of Ms Letitia Briggs SJC-EHD Sample results indicated that gasoline range hydrocarbons impacted two areas These areas were later over-excavated Over-excavation of all three gasoline tainted areas were observed by Mr. Michael Infurna SJC-PHS Approximately 70 cubic yards of gasoline tainted soils were over-excavated from the three pits This soil was removed for disposal to Forward Landfill during March 2000 g R-603.fan 2001