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<br /> 16 October 2003
<br />' AGE NC Project No 96-0235
<br /> Page 3 of 5
<br />' 12 00 feet (MW-14B) to 14 38 feet (MW-13B) below mean sea level The average ground water
<br /> elevation in the wells increased by approximately 0 6 feet since the December 2003 ground water
<br /> monitoring event r
<br />'
<br /> Figure 3 illustrates the ground water otentiometric surface based on the shallow-and deep-screened
<br /> g � p
<br /> data sets Near the former UST cluster, the shallow-screened data delineated a northeasterly water
<br />' flow pattern at a gradient of 0 002 ft/ft,the deep-screened data delineated a radial ground water flow ,
<br /> direction toward the west-nothwest at a gradient of 0 008 ft/ft Near the former UST No 3
<br /> excavation ground water flow direction at the shallow-screened level was inferred to be towards the
<br /> southeast at a gradient of 0 005 ft/ft, ground water flow direction at the deep-screened level was
<br /> inferred to be toward the south-southwest at a gradient of 0 018 ft/ft
<br /> 32 ANALYTICAL RESULTS OF WATER SAMPLES
<br />' TPH-g was detected in the samples collected from MW-1, MW-2, MW-10, MW-14B, EW-1 and
<br /> EW-2 at concentrations as high as 21,000 micrograms per liter(µg/1) in the sample collected from
<br /> • MW-2 TPH-d was detected in samples collected from MW-1,MW-2,MW-9, MW-10, MW-11B,
<br /> MW-14B, MW-15B, EW-1 and EW-2 at concentrations as high as 19,000 µg/1 (MW-10)
<br /> BTEX compounds were detected in samples MW-1, MW-2,MW-10, MW-11B, MW-15B, EW-1
<br /> and EW-2 at maximum concentrations of 1,300 µg/1 benzene (MW-1), 400 µg/1 toluene (EW-1),
<br /> 1,300 4g/1 ethylbenzene (MW-2) and 2,200 µg/1 xylenes (MW-2)
<br /> MTBE was detected to the water samples collected from MW-9, MW-10, MW-11B, �iW-12B,
<br /> MW-13(A and B), MW-14B and EW-1 at concentrations ranging from 5 0'gg/1 (MW--13A) to
<br />' 270 µgd (EW-1) TBA was detected at a concentration of 15 µg/l in the water samples collected
<br /> from MW-6B and MW-14B Water samples analyzed from MW-2,MW-5,MW-6B,MW-7,MW-
<br /> 8A, MW-11B, MW-12B, MW-13B, MW-14B and EW-2 contained detectable concentrations of
<br /> 1,2-DCA ranging from 0 72 µg/1 (MW-SA)to 26 gg/1 (MW-14B) Concentrations ofDIPE, ETBE,
<br /> TAME and EDB were not detected above laboratory_reporting limits in any of the water samples ti
<br /> T _
<br />' collected during the March 2003 monitoring event h
<br /> Analytical results of water samples collected during the first quarter of 2003 are summarized on
<br /> Table 2 and 3,analytical results from previous monitoring evenfs are summarized on Tables 4 and 5
<br />' Figures 4 and 5 illustrate the ground water contamination plumes in upper and lower ground water
<br /> intervals, respectively The laboratory report (MAI Lab IDs 0303275-001 through 0212433--024),
<br />' chain-of-custody forms and the laboratory QA/QC report are included in Appendix B
<br /> Advanced GmEnvironmental,Inc
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