ARCHIVED REPORTS_XR0005526 - Laserfiche WebLink

Home Browse Search

2.0 RELEASE AND SITE CHARACTERIZATION INFORMATION Results of the soil sampling from under the former USTs and dispenser islands indicated that significant concentrations of gasoline hydrocarbons were detected beneath the north end of the former middle UST and in shallow subsurface soil in the vicinity of the west dispenser island The soil sample results are summarized in Table 1 and the laboratory reports are included in Appendix A The soil sample collected from 14 feet bgs under the north end of the middle former UST (Tank 2) contained 7,000 milligrams per kilogram (mglkg) of TPH-as-gasoline, 3 5 mg/kg of benzene, 90 mg/kg of ethylbenzene 590 mg/kg of xylenes and 0 024 mg/kg of MTBE Neither TPH-as- gasoline nor BTEX compounds were detected in the other five soil samples collected from beneath the former USTs MTBE was detected in one other soil sample at a trace concentration of 0 021 mg/kg TBA was detected in four of the six soil samples at a maximum concentration of 0 067 mg/kg The maximum concentration of total lead detected beneath the former USTs was 11 mg/kg I' The soil sample collected from approximately 3 5 feet bgs from beneath the east dispenser did not contain detectable concentrations of TPH-as-gasoline, BTEX or the five oxygenate compounds Total lead was detected in this soil sample at 6 1 mg/kg The soil sample collected at approximately 4 5 feet bgs from beneath the west dispenser contained 190 mg/kg of TPH-as-gasoline, 0 6 mg/kg of benzene, 10 mg/kg of toluene, 3 mg/kg of ethylbenzene, 14 mg/kg of xylenes and 130 mg/kg of MTBE The other oxygenate compounds DIPE, ETBE, TAME and TBA were not detected Total lead was detected in this soil sample at 30 mg/kg The concentrations of gasoline hydrocarbons beneath the northern end of former Tank 2 were not further investigated To investigate the lateral and vertical extent of impacted soil beneath the west dispenser, the two soil borings were drilled for soil sample collection and analysis The soil sample results are summarized in Table 1 and the laboratory reports are included in Appendix A Based on the results of the soil samples collected from the vertical soil boring D-1, the lateral extent of impacted soil appeared to be limited to the vicinity of the dispenser Only a trace concentration of MTBE was detected in the soil sample collected at 20 feet bgs from D-1 TPH- as-gasoline and BTEX were not detected in either of the soil samples collected from D-1 3