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Chemical Analysis Fourteen soil samples and six groundwater samples were analyzed at Kiff Analytical LLC, a certified analytical laboratory Samples were tested for the following, Total Petroleum hydrocarbons as Gasoline (TPHG), Benzene (B), Toluene (T), Ethylbenzene (E), Xylene (X), and Volatile Organic Compounds (VOC), Methyl-tert-butyl-ether (MTBE), and fuel oxygenates tert- Amyl-Methyl-Ether, Ethyl-tert-Butyl-Ether, Di-Isopropyl Ether and Tert-Butyl Alcohol (TAME, ETBE, DIPE, TBA) and Bunker Oil using EPA Methods 3550, 3510/8015, 5030, 8020 and 8260 Bunker Oil was selected as an additional contaminant of potential interest given the area's railroad regional history of use The analytical reports are attached and the data is presented in Tables 2 and 3 below Discussion The site is underlain by silt and clay vadose soil/sediment at depths of about 10 to 15 feet A sandy and clayey sand aquifer underlies the silt-clay strata to a depth of about 20 feet, and is in turn underlain by silty clay and sandy clay strata. The deepest boring, B-3 was advanced adjacent to the north side of the tank pit Soil sample data collected through the vadose zone and aquifer revealed contaminant presence The most elevated concentrations of TPHG, TPHD and Bunker Oil occurred in samples from Borings B-3 and B-4 near the former tank pit and Boring B-5 just north of the Public Works Building (see Figures 2 and 3, and Tables 2 and 3) Contaminants appear to have migrated north and east along the capillary fringe Sheen and separate phase product was observed in Borings B-3, B-4 and B-5 TPHG and Bunker Oil were detected in aquifer strata in Borings B-3, B4 and B-5 The highest levels of Bunker Oil in soil were detected in B-4 slightly east of the former tank pit Contaminants were not detected in the deepest soil collected in B-3 adjacent to the tank pit at a depth of 23 5 to 24 feet Low levels of MTBE and TAME are also present m soil samples from B-1 and B-3 High concentrations of TPHG were present in samples from Barings B-3, B-4 and B-5 MTBE, TAME and TBA were detected in groundwater samples from Borings B-1 and B-3, with the highest concentration of MTBE in B-3 at 2600 ug/1 Boring B-1 was located in an assumed upgradient position, yet showed 330 ug/l dissolved MTBE The presence of TAME and TBA may suggest that the fuel is somewhat degraded Bunker Oil was detected in all groundwater samples including the assumed upgradient locations This relatively widespread occurrence of Bunker Oil suggests another source for this contaminant The contaminant distribution was most elevated around the former tank pit and in the assumed downgradient direction (northerly) toward and under the Public Works Building The underground tank source has been removed for some time These data indicate a large residual component of TPH contaminants as well as MTBE and oxygenates are present in the tank pit . vicinity Page 4 of 8 i 31