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Ms Margaret Lagono Page 5 of 8 ' Soil Analytical Results ' Bonnes No detectable concentrations of gasoline oxygenate additives, alcohols, EDB or DCA were reported in any soil sample collected from any boring Except in boring CB3, no significant levels of petroleum hydrocarbons were detected in soil samples collected from the vadose zone Moderate levels of TPHg were detected to vadose soil samples in boring ' CB3 However, the laboratory indicated that the hydrocarbon contaminant was depleted in light ends and aromatic constituents, presumably as a result of the operation of the vapor extraction system (see narrative and chromatograms in Attachment C) ' In boring CB 1/CB 1 A, detectable levels of hydrocarbons in soil were first present between the depths of 50- 55 felt Concentrations increased with depth to a maximum level at 80 feet Beneath this depth concentrations rapidly decreased until at 112 and 125 feet only non-detectable to trace levels were present Very low concentrations of TPHg and BTEX were reported in the sample collected at 135 feet ' In boring CB2, moderate levels of gasoline hydrocarbons were present in saturated soils from 45 feet to 65 feet In bonngs CB3 and CB4, only very low levels of hydrocarbons were present in saturated soils The only soil sample collected from boring CB5 was at a depth of 85 feet where 640 parts per million (ppm) ' TPHg was detected along with low levels of BTEX compounds Analytical results are summarized In Table I Laboratory data sheets and chain of custody documentation are included in Attachment C ' Monitoring_Well MW 14 In MW 14, low levels of TPHg, benzene and xylenes were found in the sample collected at a depth of 45 feet bgs In the sample collected at 56 feet only benzene was detected, at a concentration of 0 006 ppm Soil ' analytical results are summanzed in Table 1 Laboratory reports and chain of custody documentation are included in Attachment C ' Groundwater Analytical Results Boring CB 5 ' Discrete groundwater samples were collected from the depths of 74, 88, 112 and 140 feet Concentrations of gasoline hydrocarbons were very lugh at the depths pf 74 and 88 feet, were relatively low ui the sample from 112 feet and consisted only of trace levels of BTEX compounds at 140 feet No gasoline oxygenates or ' additives were detected in any sample TPHg was detected in all but the deepest sample, at concentrations ranging from 260 parts per billion(ppb)to 170,000 ppb BTEX compounds were detected in all samples Benzene ranged from a low of 0 7 ppb in the sample collected at 140 feet to a maximum concentration of 18,000 ppb in the sample from 88 feet Analytical results are summarized to Table 2 Laboratory data sheets and chain of custody documentation are included in Attachment C Monitonnia Well MW 14 ' Very high concentrations of gasoline hydrocarbons, including methyl tent butyl ether(MTBE), were detected in the groundwater sample collected from MW 14 No oxygenates or additives other than MTBE were detected ' a«tuioa. �ao