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Mr Harlin Knoll <br /> Page 2 of 2 <br /> . respectively Purged groundwater was contained in labeled Department of Transportation (DOT) <br /> approved drums pending disposal Copies of field purge logs and water level measurements are included <br /> in Attachment A <br /> Groundwater Analytical Results <br /> Elevated levels of dissolved gasoline constituents were detected in the groundwater sample collected from <br /> well MW5, and relatively low levels were detected in samples collected from well MWl No gasoline <br /> constituents were detected in the sample collected from well MW4 <br /> Well MW5 contained TPHg at a concentration of 99,000 parts per billion (ppb), benzene at 5,600 ppb, <br /> toluene at 6,000 ppb, ethylbenzene at 2,000 ppb, and xylenes at 11,000 ppb Well MW1 contained TPHg <br /> at a concentration of 250 ppb, benzene at 0 8 ppb and ethylbenzene at 7 0 ppb, and xylenes at 3 2 ppb No <br /> toluene was detected in well MW 1 Analytical results are summarized in Table 3 Laboratory data sheets <br /> and chain of custody documentation are included in Attachment B Figure 3 presents a benzene <br /> isoconcentration map utilizing the most recent analytical results Attachment C contains graphical <br /> representations of TPHg and benzene concentrations over time in site wells <br /> SUMMARY AND CONCLUSIONS <br /> Groundwater at the site flowed in a northeasterly direction, and the potentiometnc surface in site wells fell <br /> an average of 0 53 feet between August 16, 2002 and November 12, 2002 The water level lies above the <br /> • screened interval in wells MW4 and MW5 <br /> TPHg and BTEX were not detected in well MW4 Gasoline constituents in well MWl decreased from <br /> the previous quarter by 67-93% Gasoline constituents in well MW5 remain well below historic highs for <br /> that well <br /> Please contact John Lane at(209) 83 8-9888 if you have any questions or comments regarding this report <br /> Respectfully, <br /> Ground Zero Analysis, Inc <br /> Ute` ED GFp <br /> Sean Garvey <br /> Staff Geologist JOHIN P <br /> f - LANCE7 <br /> No &795 m <br /> John P Lane Al <br /> CA Registered Geologist 6795 ti Opf <br /> Attachments <br /> cc Mr Carl Knowles <br /> Mr Patrick D Riddle, Attorney at Law <br /> . Mr Marty Hartzell, CRWQCB Sacramento <br /> G\Data\GROUNDZE\KNOWLES i AM\REPORTS\QMR\4QM2002 doc <br />