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. 11 April 2001 AGE-NC Project No 95-0143 Page 4 of 6 ' 3 2 ANALYTICAL RESULTS OF WATER SAMPLES During the November 2000 monitoring event, TPH-g was detected in samples collected from monitoring wells MW-3,MW-6,MW-7 and MW-9 at concentrations ranging from 780 pg/l(MW-7) to 110,000 pg/l(MW-3) BTEX compounds were detected in the same four wells at concentrations as high as 26,000 pg/l (xylenes in the sample from MW-3) Fuel oxygenates were not detected in ' samples collected from the site during the November 2000 sampling event Figure 4 illustrates the approximate extent of TPH-g and benzene contamination in groundwater ' Measurable free product was not encountered in any of the wells on the site Analytical results of ground water samples collected during the November 2000 monitoring event are summarized on ' Table 2 Analytical results of historical ground water samples are summanzed on Table 3 The laboratory report(MAI Laboratory I D Nos 54612 through 54620)and cham-of-custody forms are included in Appendix B ' High concentrations of dissolved oxygen were observed in wells MW-7, VW-1 and VW-3 during monitoring of the SVE/air sparging system on 06 October 2000 Concentrations of dissolved oxygen • had decreased significantly by the 15 November 2000 monitoring event, following shut-down of the air spargmg system on 27 October 2000 Dissolved oxygen data are summarized on Table 4 3 3 OPERATION OF SVE/IAS UNITS ' The SVE system operated at a capacity of approximately 207 cubic feet per minute (cfin) during the quarter The burner temperature was maintained near 650°F for catalytic operation until shut down on 27 November 2000 The intake vapor stream was approximately 6 to 7 percent of the lower ' explosive limit (LEL) Field measurements of flow rate, vacuum potential and organic vapor concentration in the air stream from each extraction well were measured on a periodic basis Organic vapor was measured at concentrations as high as 7 5 ppm in the extracted air streams (VW5) The measurements for each ' well are shown in Table 7 ' 3 4 ANALYTICAL RESULTS OF SOIL VAPOR SAMPLES Concentrations of TPH-g in soil vapor samples extracted from the inlet port of the SVE system ' ranged from less than the laboratory reporting limit (50 pg/1) to 250 pg/1 Soil vapor concentrations have dropped signficantly during the last three quarters Analytical results are summarized on Table 5 Analytical results of historical soil vapor samples are summarized on Table 6 The laboratory I Advanced GeoEnvironmentai,Inc 1