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mg/Kg in HA-2B Sample HA-213 showed hydrocarbons as gas at 24 mg/kg but as - noted in the analytical data sheets the probable source of these hydrocarbons is the diesel These locations corresponded approximately with the location of he sample taken dunng the UST removal that showed high concentrations of hydrocarbons The detection lirruts used in the analyses are included with the analytical data sheets and vanes according to the laboratory but are lower than the following • TPH-diesel 12 mg/Kg • TPH-gasoline 12 mg/Kg • BTEX 2 4 mg/Kg Based on the stated analytical results, hydrocarbon contamination appears to be narrowly confined to the location of the former USTs During the rig drilling activities there were no indications of hydrocarbon odors and no hydrocarbon stained samples or soil cuttings were observed However, during the drilling of the hand auger borings (HA-1 and HA-2), soils containing layers of hydrocarbon stained clay were encountered in the vadose zone and hydrocarbon odor was detected at a depths greater than five feet A visible sheen was on the water observed in boring HA-2 4.2 Groundwater Analytical Results The analytical results of groundwater sampling are presented in Table 2 Copies of the analytical data sheets are included in Appendix E The water was sampled from well MW-1 which was located in the down-gradient direction from source of contamination as determined form the Mobil Oil Distribution Center Survey of the groundwater elevations from on-site wells indicated that the gradient direction is north Weast with a magnitude of 0 37 feet per hundred feet Based on the site specific gradient, MW-1 remains down-gradient of the contaminant source area Groundwater was analyzed for the presence of the TPH as gas, TPH as diesel and BTEX. Analytical results indicated N D for all analytes The reporting hrruts for the above results are as follows. • TPH-diesel 50 mg/Kg • TPH-gas 20 mg/Kg • BTEX 5 mg/Kg 9 i3RUNSING ASSOCIATES, IN