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I29 January 2001 AGE-NC Project No 00-0725 Page 3 of 11 TPH-g was detected in all grab ground water samples at concentrations ranging from 370 µg11 in I sample B1-H2O to 55,000 microgram per liter(µg11) in sample 133-H20 Excluding sample B5-H20, benzene was detected in the remaining samples at concentrations ranging from 0 54µg11 in sample ' B1-H20 to 160 µg/1 in sample B3-H20 Toluene was detected in all five ground water samples at concentrations ranging from 11 to 25 µg/1 Ethylbenzene was detected in sample B3-H2O at 58 µg/1 and sample 134-H20 at 2 5 yg/l Xylenes were only detected in samples B2-H20, B3-H20 and 134- H20 at concentrations of 230 µg11, 120,ug/l and 19 µg/1, respectively methyl-tertiary butyl ether (MTBE) was not detected in any of the ground water samples In addition, the remaining fuel oxygenates were not detected in sample B3-H20 TPH-g and various volatile organic compounds were detected in the grab ground water samples collected from the site Benzene concentrations exceed the State of California - Department of I Health Services (DHS)maximum contaminant level (MCL) for drinking water in samples collected from boring B2,B3 and B4 The hydrocarbon plume has not been defined with the sample locations 3.0. PROCEDURES . All field procedures were overseen by an AGE representative under the supervision of a California Registered Geologist Procedures for soil excavation, soil sampling,well construction and sampling and equipment decontamination are outlined below The scope of work was preformed in accordance with Interim Soil Remediation Work Plan, dated 31 August 2000, approved by the PHS-EHD by letter dated 03 October 2000 3 1 SOIL,EXCAVATION The hydrocarbon-impacted soil was removed with an excavator outfitted with a 2 45 cubic-yard bucket Soil was excavated from the northern most dispenser near soil probe boring 133 Soil was stockpiled Immediately on the eastern edge of the site Excavated soil was field screened for the presence of volatile organic compounds using an OVM Ground water was present within the limits excavation at a depth of 15 feet bsg Saturated soil was excavated from below the water table and stockpiled on site within a soil containment berm Soil was placed within plastic for temporary storage The open excavation area was surrounded by caution fencing No AGE or subcontractor personnel was allowed Into the excavation The extent of the soil excavation, sampling locations and temporary soil stockpile location are depicted in Figure 3 • IAdvanced GeoEnvironmental,Inc I