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4 0 CONCLUSIONS AND RECOMMENDATIONS <br /> Soil and groundwater beneath the site are impacted by gasoline and kerosene hydrocarbons <br /> Based on the presence of petroleum hydrocarbons within the unsaturated (vadose), capillary <br /> fringe and saturated soil intervals at G3, the primary source of the impacts appears to be the <br /> former 1,000-gallon gasoline UST (UST#2) The bulk of the hydrocarbon mass is concentrated in <br /> subsurface sod beneath the south end of former UST#2, and to the east near the former <br /> dispenser island <br /> Vertically, the extent of impacted soil is not defined at the total drilling depth of 35 feet bgs <br /> ' Laterally, the extent of impacted vadose zone soil is defined to the south by G-2 and to the east by <br /> G-1 The lateral extent of impacted capillary fringe and saturated zone soil is only defined to the <br /> south by G-2 <br /> The extent of impacted groundwater at the groundwater table is not defined Concentrations of <br /> ' petroleum hydrocarbons in groundwater appear to decline significantly to the south <br /> Based on the distribution of petroleum hydrocarbons in sod and groundwater, it appears that <br /> gasoline from the former UST#2, migrated through the vadose zone soil to the groundwater table <br /> and then migrated to the east Based on the soil sample analytical results from G-1 near the <br /> former dispenser island and from G-2 at the south end of the former 8,000-gallon gasoline UST <br /> (UST#1), impacts at these locations appear to be limited to shallow soil and do not extend <br /> through the vadose zone to the groundwater table <br /> TPH-as-diesel and the oxygenate compounds were not detected in any of the sod or groundwater <br /> samples analyzed TPH-as-motor oil was detected in only two sod samples at concentrations <br /> ranging from 19 to 23 mg/kg Total lead was detected in sal at a maximum concentration of 8 6 <br /> mg/kg, which is a non-hazardous concentration probably representative of background soil <br /> conditions <br /> Based on the results of this investigation, Ramage Environmental recommends that a work plan <br /> be prepared, which outlines additional environmental corrective actions to be completed at the <br /> site Prior to proceeding with the additional corrective actions, PHS/EHD had requested in their <br /> ' letter dated May 16, 2000 (Appendix A), that the interested parties meet to discuss the site <br /> information and to prioritize the work relative to five other county sites <br /> 9 <br />