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41 <br /> • John Pestana QTIP Trust <br /> t Page 4 <br /> ppm extractable hydrocarbons, identified by the laboratory as motor oil Fuel fingerprint analyses on <br /> the soil samples collected from borings HB8 through HB 10 reported unidentified C9-C40 <br /> hydrocarbons ranging from 1 5 to 12 ppm In a follow up conversation, laboratory personnel indicated <br /> that the resulting chromatogram pattern from the HB9 sample appeared to be from a"heavy fuel" and <br /> the pattern from the HB 10 boring was likely gasoline The concentration detected nn HB8 was very <br /> near the detection limit and no specific pattern was recognizable <br /> In an effort to differentiate on site contamination (known leak of unleaded gasoline and potential leak <br /> from waste oil UST)from a potential off site source(motor oil in HB 11), Ground Zero directed Argon <br /> to transmit sample extracts from samples collected from borings HBI, HB4, and HB5 to Sequoia <br /> under chain of custody for fuel fingerprint analyses This sample set represents an array of samples <br /> from the former waste oil UST (HBI) to the northern property boundary (BB 11) along the path of <br /> groundwater flow <br /> Sequoia was directed to analyze the extracts, within the accepted holding time of 45 days, on the same <br /> instrument on which the sample from HB 11 was run in order to compare chromatograms Results <br /> indicated petroleum hydrocarbons as hydraulic oil was present in the vicinity of the former waste oil <br /> UST, which differs from the motor oil detected in boring HB 11 Samples from 1HB4 and HB5, located <br /> in the path of groundwater flow between borings HB 1 and HB 11, contained relatively low levels of <br /> gasoline hydrocarbons,but no detectable hydraulic oil or motor oil <br /> Results of fuel fingerprint analyses are summarized in Table 1 Laboratory reports and chain of <br /> custody documentation are included in Attachment D and copies of the chromatograms are included in <br /> Attachment E <br /> SUMMARY AND CONCLUSIONS <br /> Low to moderate levels of residual gasoline hydrocarbons remain on site in capillary soil immediately <br /> north and northeast of the former USTs and along the former product lines, which run between the <br /> former pump islands There appears to be little or no residual contamination associated with vadose <br /> zone soil Subsurface soil in the vicinity of the former waste oil UST has apparently been impacted by <br /> heavier petroleum distillates, reported by the laboratory to be hydraulic oil <br /> Very low levels of hydrocarbons, identified by the laboratory as gasoline and heavier petroleum <br /> distillates were detected in soil along the northern boundary of the property Moderate levels of <br /> gasoline and motor oil have impacted the northeast corner of the property <br /> The absence of motor oil and hydraulic oil in soil samples collected from bonngs HB4 and 1HB5 <br /> suggest that the source of motor oil in boring 111311 is not the former USTs at the site and that the <br /> apparent residual hydraulic oil in soul near the former waste oil UST has not migrated significantly <br /> north of the former UST <br /> pedam OWsumrpt.doc <br />