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5.0 ANALYTICAL RESULTS <br /> Preliminary analysis by gas chromatography revealed hydrocarbon in only one <br /> sample from borehole B-7 at 10-11.5 feet. A second sample from the same <br /> borehole at 15-16.5 feet showed the presence of some contaminant, but was not <br /> identified as petroleum hydrocarbons by this method. <br /> These two samples were sent to the IT Cerritos Laboratory, Cerritos, <br /> California, for base, neutral , and acid extractibles analysis using gas <br /> chromatography/mass spectroscopy. These results also appear in Appendix VI. <br /> These analyses did not detect the presence of any materials on the EPA <br /> Hazardous Substances priority list. The sample that was initially reported to <br /> have 1000 ppm hydrocarbon by gas chromatography analysis was confirmed to have <br /> only 50 ppm by the more sensitive GC/Mass spec analysis (Borehole B7 10-11.5 <br /> feet) . The second sample was reported to have 500 parts per billion of an <br /> unknown substance (not on the EPA hazardous substances priority list) . <br /> This area was filled before construction of the parking lot and warehouse <br /> facility. The material used for fill probably was not clean gravel , crushed <br /> rock, or sand. These results do not indicate any evidence of leakage from the <br /> tank. The small amount of contamination is most likely due to some organic <br /> material (such as asphalt) in the original backfill . <br /> It should be noted that, based on known geology of the area, the water table <br /> level is estimated to be at 50 to 80 feet below grade. <br /> 6 <br /> ENG:0551/02196 <br />