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I28 March 2002 AGE-NC Project No 95-0141 ' Page 3 of 4 ' 3 2 ANALYTICAL RESULTS FROM GROUND WATER SAMPLES Monitoring wells MW-1 through MW-8 were sampled on 12 February 2002, wells MW-1 through MW-5 were "drowned", and may not have yielded samples fully representative of ground water conditions near the top of the saturated zone where fuel hydrocarbons would be expected to have the greatest Impact The analytical results of the ground water samples were as follows • TPH-g was detected in ground water samples collected from all monitoring wells except MW-5 TPH-g concentrations ranged from 58 micrograms per liter (µg/1) in MW-7 to 150,000 µg/1 In MW-1 BTEX compounds were detected in the ground water samples collected from monitoring wells MW-1 through MW-6 at concentrations as high as 8,600 µg/1 benzene (MW-1), 25,000 gg/1 toluene (MW-1), 3,200 µg/1 ethylbenzene (MW-1) and 15,000 µg/1 xylenes (MW-1) • TBA was detected in the samples collected from MW-5 and MW-6 at concentrations of 6 1 µg/1 and 9 1 µg/1,respectively MTBE was detected in the sample collected from MW-6 at a concentrations of 1 1 µg/1 DIPE, ETBE and TAME were not detected In the ground lie water samples collected from the site • 1,2-DCA was detected in ground water samples collected from all monitoring wells Concentrations ranged from 4 6 µg/1 (MW-4) to 310 µg/1 (MW-1) EDB was not detected in the ground water samples collected from the site Laboratory results of water samples analyzed for petroleum hydrocarbons are summarized in Tables 2, 3 and 4 The laboratory reports for the quarterly monitoring event (MAI Lab IDs 90486 Ithrough 90493) QA/QC reports and chain-of-custody form are Included in Appendix B The areal extent of TPH-g,benzene and 1,2-DCA Impacted ground water Is Illustrated on Figures 4, 5 and 6, respectively 4.0. SUMMARY AND CONCLUSIONS The findings of the 12 February 2002 site Investigation events include the following • Measured ground water elevation Is approximately 11 8 feet below msl, and was within the screened interval of the two shallow monitoring wells (MW-7 and MW-8) Ground water was approximately 9 to 10 feet above the screened intervals of MW-1 through MW-5 and was approximately 40 feet above the screened Interval of the deep well MW-6 Advanced GeoEnvironmental,Inc