ARCHIVED REPORTS_MONITORING WELL INSTALLATION REPORT - SITE ASSESSMENT WORK PLAN

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' 25 February 2005 • AGE-NC Project No. 98-0500/04-1127 Page 6 of 7 3.5. LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES Based on the data collected on 18 January 2005 from monitoring wells MW-36 and MW-37, the ' hydrocarbon-impact to ground water is better defined. Ground water samples were collected from both of the newly installed well were purged and were submitted for initial laboratory analysis. • TPH-g was detected in monitoring well MW-36 at a concentration of 310 micrograms per liter(µg/1); while TPH-g was not detected in monitoring well MW-37. • BTEX compounds were detected in the sample from well MW-36 at concentrations of 11 µg/l benzene,8.0µg/1 toluene, 1.9µg/l ethylbenzene and 17µg/1 xylenes.BTEX compounds were not detected in the sample from well MW-37. ' 0 1,2-DCA was detected in the ground water sample collected from monitoring well MW-36 at a concentrations of 140 µg/l.However, 1,2-DCA was not detected in the sample collected ' from well MW-37. The estimated vertical extent of dissolved TPH-g and 1,2-DCA is shown on Figures 3 and 4, respectively. Analytical results of the monitoring well ground water samples are presented in the '• laboratory report (MAI Work Order 0501265), with quality assurance/quality control (QA/QC) reports and chain of custody forms in Appendix E. GeoTracker submittal confirmation sheets are presented in Appendix F. 4.0. CONCLUSIONS ' The findings from the well installation and initial ground water monitoring event are as follows: ' Petroleum hydrocarbons were detected in only two, shallow soil samples from boring MW37,TPH-g at maximum concentrations of 470 mg/kg.BTEX compounds were detected in the same samples collected at depths of 60 feet and 70 feet bsg. • 1,2-DCA was detected in nine soil samples, with concentrations decreasing with greater depth. The highest concentrations of 1,2-DCA was detected at 60 feet, along with the only detection of EDB. • The depth to ground water decreased dramatically during purging and sampling of well MW-36 while, the depth to water was generally constant during the purging and sampling ' of well MW-37. • TPH-g,BTEX and 1,2-DCA were detected in the newly installed monitoring well MW-36, established in HU6; while the deeper monitoring well MW-37 established in HU7 had no • detections of hydrocarbons or fuel additives. ' Advanced GeoEnvironmental,Inc.