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Ms. Lori Duncan January 19,2011 RE:2911 E.Fremont St,Stockton,CA Page 4 of 6 Analytical Results Soil Analytical Results Selected soil samples from each boring were submitted to Argon Laboratories(DHS Certification#2359) for analysis of total petroleum hydrocarbons as gasoline(TPHg)and volatile organic compounds(VOCs), including gasoline constituents, using EPA Method 8260B. LPB-1: Soil samples collected from the depths of 30.5, 35, 40, and 42 feet bgs were submitted for analysis. Shallower samples were not submitted because field observations confirmed that hydrocarbons were present in the immediate vicinity of the clarifier to at least 20 feet bgs, as found in the previous investigation(Krazan,April 2010). The sample collected from LPB-1 at a depth of 30.5 feet contained gasoline constituents at relatively low levels, notably TPHg at 650 milligrams per kilogram (mg/kg), ethylbenzene at 0.27 mg/kg,total xylenes at 2.8 mg/kg,and naphthalene at 0.63 mg/kg. In addition,the sample contained the chlorinated solvents 1,1,2,2-tetrachloroethane and tetrachloroethene (PCE) at concentrations of 1.7 mg/kg and 0.24 mg/kg, respectively. No gasoline constituents or chlorinated solvents were detected in the samples collected from depths of 35, 40, and 42 feet bgs. LPB-2: Soil samples collected from the depths of 20.5,30.5,and 36 feet bgs were submitted for analysis. No gasoline constituents or chlorinated solvents were detected in any of the samples collected from boring LPB-2. LPB-3: Soil samples collected from the depths of 20, 30,and 41.5 feet bgs were submitted for analysis. No gasoline constituents or chlorinated solvents were detected in any of the samples collected from boring LPB-3. LPB-4: Soil samples collected from the depths of 20,30,and 42.5 feet bgs were submitted for analysis. No gasoline constituents or chlorinated solvents were detected in any of the samples collected from boring LPB-4. Table 1 summarizes analytical results of soil samples collected near the inactive clarifier.Attachment 2 contains a copy of the laboratory report. Groundwater Analytical Results Groundwater samples from each boring were submitted to Argon Laboratories(DHS Certification#2359) for analysis of total petroleum hydrocarbons as gasoline(TPHg)and volatile organic compounds(VOCs), including gasoline constituents, using EPA Method 8260B. No gasoline constituents were detected in any of the groundwater samples collected from borings LPB-1 through LPB-4. However,PCE was detected at 2.6 micrograms per liter(µg/L)in LPB-1, 1.3µg/L in LP -2 and LPB-4, and 1.0 µg/l, in LPB-3. 10759-SUMMARY LTR