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} Former Beacon Station No. 474 May 15, 2000 Stockton California Results of Additional Subsurface Investigation •. Nine soil samples collected from soil boring B7 (monitoring well MW-12) at depths ranging from 10 to 112 feet bsg were selected for analysis. Analytical results of eight samples collected from 30 to 112 feet bsg indicated concentrations of TPHg and BTEX compounds. The highest TPHg and BTEX concentrations were reported for the 30, 50, 70 and 85460t samples. Concentrations of TPHg ranged from 120 to 10,000 ppm, and concentrations of benzene ranged up to 40 ppm. Concentrations of TPHg and benzene in the 92 to 112-foot samples ranged from 1.4 to 5.3 pprn, and 0.016 to 0.37 ppm, respectively. The reporting limit for TPHg for these analyses was 1.0 ppm. The reporting limit for benzene for these analyses was 0.0050 ppm. No fuel oxygenates were reported in soil samples from soil boring B7. A concentration of 84,000 ppb TPHg and concentrations of BTEX compounds ranging from 2400 to 12,000 ppb were reported for the hydropunch groundwater sample collected from soil boring B7. No fuel oxygenates were reported in the soil groundwater sample. Eight soil samples collected from soil boring B8 (vapor extraction well VW-7) at depths ranging from 10 to 105 feet bsg were selected for analysis. Analytical results of the 80 and 90-foot samples indicated TPHg concentrations of 56 and 1 ppm, respectively. The reporting Emit for TPHg for these analyses was 1.0 ppm. Benzene was reported in the same samples at concentrations of 0.48 and 0.0071 ppm, respectively. Benzene was also reported in the 70- foot sample at a concentration of 0.0069 ppm. The reporting limit for these benzene analyses was 0.0050 ppm. Xylenes were also detected in the 90-foot sample at a concentration of 0.013 ppm. No fuel oxygenates were reported in soil samples from soil boring B-8. A concentration of 1700 ppb TPHg and concentrations of BTEX compounds ranging from 1.5 to 51 ppb were reported for the hydropunch groundwater sample collected from soil boring B8. Methanol, MTBE and TBA concentrations of 32, 2.3 and 5.4 ppb, respectively, were also reported for the groundwater sample; no other fuel oxygenates were reported in the groundwater sample. Seven soil samples collected from soil boring B9 (air sparge well AS-1) at depths ranging from 10 to 105 feet bsg were selected for analysis. Analytical results of the 60 and 80-foot 1474.22rpt 7 HORIZON ENVIRONMENTAL INC.