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1 <br /> Chemical Analysis <br /> Fourteen soil samples and six groundwater samples were analyzed at Kiff Analytical LLC, a <br /> certified analytical laboratory. Samples were tested for the following; Total Petroleum <br /> hydrocarbons as Gasoline (TPHG), Benzene (B), Toluene (T), Ethylbenzene (E),Xylene (X), and <br /> Volatile Organic Compounds (VOC), Methyl-tert-butyl-ether (MTBE), and fuel oxygenates tert- <br /> Arnyl-Methyl-Ether, Ethyl-tert-Butyl-Ether, Di-Isopropyl Ether and Tert-Butyl Alcohol (TAME, <br /> ETBE, DIPE, TBA) and Bunker Oil using EPA Methods 3550, 3510/8015, 5030, 8020 and 8260. <br /> Bunker Oil was selected as an additional contaminant of potential interest given the area's <br /> r railroad regional history of use. The analytical reports are attached and the data is presented in <br /> Tables 2 and 3 below. <br /> Discussion <br /> The site is underlain by silt and clay vadose soil/sediment at depths of about 10 to 15 feet. A <br /> sandy and clayey sand aquifer underlies the silt-clay strata to a depth of about 20 feet, and is in <br /> turn underlain by silty clay and sandy clay strata. The deepest boring, B-3 was advanced adjacent <br /> to the north side of the tank pit. <br /> Soil sample data collected through the vadose zone and aquifer revealed contaminant presence. <br /> The most elevated concentrations of TPHG, TPHD and Bunker Oil occurred in samples from <br /> Borings B-3 and B-4 near the former tank pit and Boring B-5 just north of the Public Works <br /> Building (see Figures 2 and 3, and Tables 2 and 3). Contaminants appear to have migrated north <br /> and east along the capillary fringe. Sheen and separate phase product was observed in Borings <br /> B-3, B-4 and B-5. TPHG and Bunker Oil were detected in aquifer strata in Borings B-3, B-4 and <br /> B-5. The highest levels of Bunker Oil in soil were detected in B-4 slightly east of the former <br /> tank pit. Contaminants were not detected in the deepest soil collected in B-3 adjacent to the tank <br /> pit at a depth of 23.5 to 24 feet. Low levels of MTBE and TAME are also present in soil samples <br /> from B-1 and B-3. <br /> High concentrations of TPHG were present in samples from Borings B-3, B-4 and B-5. MTBE, <br /> TAME and TBA were detected in groundwater samples from Borings B-I and B-3, with the <br /> highest concentration of MTBE in B-3 at 2600 ug/i. Boring B-1 was located in an assumed <br /> upgradient position, yet showed 330 ug/l dissolved MTBE. The presence of TAME and TBA <br /> may suggest that the fuel is somewhat degraded. Bunker Oil was detected in all groundwater <br /> samples including the assumed upgradient locations. This relatively widespread occurrence of <br /> Bunker Oil suggests another source for this contaminant. <br /> The contaminant distribution was most elevated around the former tank pit and in the assumed <br /> downgradient direction (northerly) toward and under the Public Works Building. The <br /> underground tank source has been removed for some time. These data indicate a large residual <br /> component of TPH contaminants as well as MTBE and oxygenates are present in the tank pit <br /> vicinity. <br /> Page 4 of 8 <br />