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I ' 19 December 2005 AGE-NC Project No 95-0141 ' Page 4of5 • TAME was detected in ground water samples from MW-8B at a concentration of 34 µg11 ' EDB was detected in ground water sample EX-1 at a concentration of 180 µg/1 ' The areal extent of TPH-g-and 1,2-DCA-impacted shallow and deep ground water is illustrated on Figures 5 and 6 Laboratory results of water samples analyzed are summarized in Table 2 The ' laboratory reports for the quarterly monitoring event (CTEL Project Numbers CT214-0508035), quality assurance and quality control (QA/QC) reports and chain of custody form are included in Appendix D GeoTracker confirmation pages of the submitted laboratory electronic deliverable ' format files are included in Appendix E 4.0. SUMMARY AND CONCLUSIONS The findings of the Third Quarter 2005 site investigation include the following ' At the time of the August 2005 ground water monitoring event, ground water elevations at the site ranged from 9 51 feet to 10 33 feet below MSL The shallow ground water was ' inferred to flow generally towards the east, at a gradient between 0 002 ft/ft and 0 005 ft/ft, while the deeper ground water zone was inferred to flow generally toward the southeast, at a gradient of 0 005 ft/ft • TPH-g was detected in ground water samples collected from six of the sixteen wells at the site at concentrations as high as 170,000 pg/l TPH-g-impacted shallow ground water has been defined (Figure 5) However, the TPH-g-impact to the deeper ground water zone has not been defined toward the east and to a lesser degree south and north (Figure 5) • Various BTEX constituents were detected in ten of the sixteen ground water wells The ' benzene concentrations detected in the wells exceeded the DHS' Maximum Contaminant Level(MCL)for benzene in drinking water The concentrations of toluene,ethylbenzene and ' total xylenes were also significantly above their respective MCLS • 1,2-DCA was detected in ground water samples collected from seven of the sixteen wells at the site at concentrations as high as 230 pg/l (EX-1) The detected concentrations of 1,2-DCA were above the MCL 1,2-DCA-impacted shallow ground water has not been defined toward the east, and 1,2-DCA-impacted deeper ground water zone has not been defined toward the south, east and north A map illustrating the approximate extent of ' 1,2-DCA in shallow and deep ground water is presented on Figure 6 • EDB was detected in ground water sample EX-1 at a concentration of 180 µg/1 EDB has ' been detected intermittently in well EX-1, located near the former UST location • The contaminant plume has not been fully defined to the northeast (MW-5 location), there Advanced GeoEnvironmental,Inc