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mg/kg, respectively. Additional information can be found in the Condor Earth Technologies, hic. (Condor)-prepared Tank Pull Testing Results, dated 18 November 1991. Based on the contamination detected in the soil samples collected during the UST removals the San Joaquin County Environmental Health Department(EHD) directed the investigation of the TPH-g and TPH-d contaminated soil. SITE ASSESSMENT ACTIVITIES On 22 August 1995,three hydropunch soil borings(HP-1,HP-2 and HP-3)were advanced at the site. TPH-g and BTEX were detected in soil and ground water samples collected from each boring, at maximum concentrations of 300 mg/kg TPH-g, 190 mg/kg TPH-d, 1.2 kg/mg benzene, 3.1 mg/kg toluene, 5.5 mg/kg ethylbenzene and 22 mg/kg in soil sample HP-1-1 P, and 1.0 micrograms/liter (µg/1)TPH-g,0.24µg/1 TPH-d,260µg/1 benzene,8.4µg/1 ethylbenzene and 36µg/l xylenes in water sample HP-1). On 29 August 1996,five probe borings were advanced at the site.TPH-g,BTEX and methyl-tertiary butyl ether(MTBE)were detected in the soil and ground water samples collected from the borings advanced in the northern portion of the site. On 10 September 1997, four ground water monitoring wells (MW-1, MW-2, MW-3 and MW-4) were installed at the site to investigate and monitor the lateral extent ofimpacted groundwater.TPH- g, BTEX, and MTBE were detected in the soil samples from borings MW-2 and MW-4. TPH-g, BTEX,MTBE,tertiary amyl methyl ether(TAME)and tertiary butanol(TBA)were detected in the ground water samples collected from the wells on 18 September 1997.Ground water elevation data at the site indicated that the ground water was being controlled by the active island drainage pumping system adjacent to the site. Quarterly ground water monitoring at the site has been on-going since September 1997 to the present. The inferred ground water flow direction at the site has been consistently toward the southeast.Quarterly surface water sampling of the north and south ends of the drainage ditch(DDN and DDS,respectively)and the east and west ends of the island drainage channel(IDCE and IDCW) adjacent to the site began in October 1998. Between 11 and 13 September 2000, thirteen soil borings (DP-1 through DP-9, SP-1 and HP-1 through HP-3)were advanced at the site.MTBE was detected in the four-foot sample collected from DP-4 and MTBE and TAME were detected in the eight-foot soil sample collected from DP-5.MTBE was detected in the ground water samples collected from borings DP-1 through DP-6,DP-8,DP-9 and HP-2 at concentrations as high as 37,000 µg/l (DP-5). Additional information and tabulated analytical data from this investigation can be found in the Condor-prepared Soil and Ground water Investigation and Sensitive Receptor Survey Report, dated 02 October 2000. Advanced GwEnvironmeatal,Inc.