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' 28 October 2005 AGE-NC Project No 95-0141 ' Page 4 of 5 • 1,2-DCA was detected in ground water samples collected from eight out of the sixteen wells ' tested MW-3, MW-5, MW-7, MW-8A/B, MW-9B, MW-11B, and EX-1 showed concentrations of 1,2-DCA ranging from 6 7 pg/1 (MW-9B) to 130 �ig/l (EX-1) ' • TAME was detected in ground water samples from MW-8B at a concentration of 20 ug/l, and from EX-1 at 35 ug/l ' 0 EDB was detected in ground water sample EX-1 at a concentration of 92 µg/l 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 CT214-0505061), ' 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 Second Quarter 2005 site investigation include the following • At the time of the May 2005 ground water monitoring event, ground water elevations at the site ranged from 8 76 feet to 9 66 feet below MSL The shallow ground water was inferred to flow generally towards the northeast, at a gradient of 0 004 ft/ft,while the deeper ground water zone was inferred to flow generally toward the southeast, at a gradient of 0 004 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 120,000 µg/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 nine 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 eight of the sixteen wells at the site at concentrations as high as 130 dig/1 (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 groundwater is presented on Figure 6 As the figure suggests, Advanced GeoEnvironmentai,Inc I