SITE INFORMATION AND CORRESPONDENCE FILE 2

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TABLE 2 GROUNDWATER MONITORING DATA,FORMER EXXON RS 7-3708,2705 COUNTRY CLUB BOULEVARD,STOCKTON,CA Other Reference Depth to Groundwater Ethyl- Total TPH as Oxygenates and Dissolved Monitoring Elevation Groundwater Elevation Benzene Toluene benzene Xylenes gasoline MTBE Additives Lead Well Date (feet) (feet) (feet) (µg/L) (µg/L) (µg/L) (µg/L) OWL) (µg/L) (µg/L) W/L) fuel hydrocarbon result. e=A typical chromatogram.Four unknown peaks were observed causing a positive fuel hydrocarbon result.Chlorinated hydrocarbons are suspected. f=A typical chromatogram.An unknown peak was observed between MTBE and benzene. Chlorinated hydrocarbons are suspected. g=A typical chromatogram. Analysis of this sample by EPA Method 624 on April 17,1992(past EPA recommended holding time),was positive for the following chlorinated hydrocarbons:chlorobenzene and 1,2-dichlorobenzene. h=MTBE by EPA Method 8260. i=Unidentified hydrocarbon in the C6-C 12 range. j=1,2-Dichloroethane. k=TPH as diesel. I=Sample analyzed outside EPA recommended holding time. m=cert-Amyl methyl ether. n=Tertiary butyl alcohol. o=Grab groundwater sample collected from well Depth to groundwater =Measured from notch/mark on north edge of well casing. TPH=Total Petroleum Hydrocarbons by EPA Method 8015. MTBE=Methyl tertiary butyl ether by EPA Method 8020 Modified,except as rated. Other oxygenate and additives may include ethanol,tert-butyl alcohol,diisopropyl ether,ethyl tertiary butyl ether,tertiary amyl methyl ether,1,2-dibromoethane,and 1,2-dichloroethane by EPA Method 8260.All analytes were reported below the laboratory detection limit,except as noted. NA=Not analyzed. NC=Not calculated. NM=Not measured. NS=Not sampled. µg/L=Micrograms per liter. Note:TPH-g results beginning March 2002 include MTBE. G:\Projects\73708\Public\LeW709gw2.xls Page 19 of 19