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r ' 23 June 2005 . AGE-NC Project No 98-0432 Page 3 of 4 2005 The ground water flow direction was inferred to be toward the northwest at a gradient of approximately 0 006 foot/foot(ft/ft) near the former UST locations (Figure 3) ' 32 GROUND WATER ANALYTICAL RESULTS Petroleum hydrocarbons were detected only in distal well MW-8, TPH-g was detected at a concentration of 130 micrograms per liter(µg/1),and the BTEX compounds ethylbenzene and xylene were detected at concentrations of 2 7 µg/1 and 3 4 µg/1, respectively No petroleum hydrocarbon compounds or fuel additives were detected in the samples analyzed from monitoring wells MW-1 through MW-7 Analytical results from ground water samples are ' summarized in Tables 2 and 3 The laboratory report(CTEL Project No CT214-0504277), quality assurance/quality control (QA/QC)report,and chain of custody forms are included in Appendix B Documents confirming the upload of laboratory electronic deliverable format(EDF)files and depth ' to water measurements to GeoTracker are included in Appendix C ' 4.0. SUMMARY AND CONCLUSIONS ' The following conclusions were drawn from the results of this Investigation • During the April 2005 monitoring event, ground water was approximately 0 9 feet higher than the January 2005 quarterly sampling event This elevation represents the highest ground water elevation observed at the site over*Consecutive years of ground water monitoring The ground water flow direction was northwest at a gradient of 0 006 fl/ft in the area of the former USTs,which was consistent with the prevailing north to northwesterly flow directions_ at the site • No petroleum hydrocarbon compounds or fuel additives were detected in the samples ' analyzed from monitoring wells MW-1 through MW-7 Low concentrations of TPH-g, ethylbenzene and xylene were detected in the distal down-gradient well MW-8 for the first ' time since the well was installed in December 2002 The presence of low petroleum hydrocarbon concentrations in well MW-8 is not likely due mpg to site conditions No petroleum hydrocarbons have been detected in immediately upgradient ' wells MW-3 through MW-5 since these wells were installed in 2000 of 2001, and with the � �a exception of one low detection (8 2 µg/1) of xylenes in well MW-1 in 2000, BTEXt�3 • compounds have not been detected in site monitoring wells AGE concludes that the i .4r- detections may be an artifact of the sampling or water level sounding tools i ' Advanced GeoEnvironmental,Inc