ARCHIVED REPORTS_QUARTERLY REPORT - THIRD QUARTER 2003

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' February and August 1999 - Phase I/H and Preliminary Site Assessment • On 03 February and 27 and 28 August 1999, AGE advanced 30 soil borings (P1 through P29 and ' M 1), and collected one`grab' ground water sample at the site to assess for petroleum hydrocarbons in the subsurface. ' Total petroleum hydrocarbons as gasoline and stoddard solvent (TPH-g and TPH-ss) and various aromatic hydrocarbon compounds were detected in soil samples collected from an area along the western edge of the former lift truck building on the site (P 14, P24, P25 and ' P27);however,each detection of TPH-g was qualified with a notation that the pattern did not appear to be gasoline, but TPH-ss. TPH-ss was detected in the area of P14 at depths of 10 feet to 65 feet bsg at concentrations as high as 8,000 mg/kg; analyzed soil samples collected ' from depths of 20 feet to 55 feet bsg also contained elevated concentrations of TPH-ss,with significant concentrations detected at 45 feet and 55 feet bsg. TPH was detected in soil underlying the western area of the former lift truck building at depths of 10 feet to 65 feet bsg ' and at concentrations up to 6,300 mg/kg. Aromatic hydrocarbon compounds were detected at depths of 25 feet to 55 feet bsg at concentrations as high as 44 mg/kg(P14,P24,P25 and ' P27); however,benzene was not detected in any of the soil samples analyzed. • Chlorinated volatile organic compounds (generally VOCs), specifically tetrachloroethene (PCE), were detected in three soil samples collected from between 45 feet to 55 feet bsg. ' PCE was detected at a maximum concentration of 68 micrograms per kilogram (µg/kg) in soil samples collected from depths of 45 feet to 55 feet bsg. 1,2-DCE was detected in soil • samples collected between 45 feet and 65 feet bsg, at decreasing concentrations with ' increasing depth.In addition, 1,2-Dichlorobenzene was detected at concentrations less than 68 µg/kg in the soil samples analyzed. ' The most intensely hydrocarbon-impacted soil was encountered in the area west of the truck bay building,in borings P26 and P27. Soil contamination between depths of 10 feet bsg and 55 feet contained the highest hydrocarbon concentrations encountered. Moderate ' concentrations of TPH (1,000 mg/kg) at low concentrations (>10 mg/kg) were detected in the remaining boring samples at depths between 20 and 55 feet bsg. ' The lateral extent of impacted soil,between 35 feet and 55 feet bsg,was limited toward the west by soil boring P28 and the lateral extent of impacted soil between 30 feet and 45 feet bsg was limited to the south by soil boring M1. ' A ground water sample collected at the southern most end of the site contained TPH-d and toluene at concentrations of 110 micrograms per liter (µg/1) and 0.81 µg/1, respectively. ' There was an UST site located directly south, that was closed by the RWQCB, which may be a potential source of the TPH-d impacted ground water. • Analytical results from soil samples are summarized in Tables IA, 1B and 1C. • ' Advanced GeoEnvironmental,Inc.