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i 27 October 2000 I AGE-NC Project No 95-0143 Page 4 of 6 I3 2 ANALYTICAL RESULTS OF WATER SAMPLES During the August 2000 monitoring event, TPH-g was detected in samples collected from five of the nine monitoring wells at concentrations ranging from 150 [.g/l(MW-6)to 120,000 gg/l(MW-3) BTEX compounds were also detected in all nine of the wells at concentrations as high as 27,000 µg/1 I (xylenes in the sample from MW-3) Concentrations of TPH-g and BTEX were significantly higher in MW-7 and lower in MW-10 versus results from the second quarter monitoring event Fuel oxygenates were not detected in samples collected from the site during the August 2000 sampling Ievent 1,2-DCA was detected m MW-14 at a concentration of 4 6 µg/l Measurable free product was not encountered in any of the wells on the site Analytical results of ground water sarnples collected during the August 2000 monitoring event are summarized on Table 2 Analytical results of historical ground water samples are summarized on Table 3 The laboratory report (MAI Laboratory I D Nos 45580-45588) and chain-of-custody forms are included in Appendix B High concentrations of dissolved oxygen were observed in water samples from vapor wells MW-7, VW-1, and VW-2 during the 07 September 2000 monitoring event Dissolved oxygen levels have fluctuated significantly in MW-7, VW-1, and VW-3 during the third quarter of 2000 The concentration of dissolved oxygen in ground water remained generally stable at the site relative to Iprevious monitoring events Dissolved oxygen data are summarized on Table 4 33 OPERATION OF SVE/IAS UNITS The SVE system operated at a capacity of approximately 200 cubic feet per minute (cfiri) over the quarter The burner temperature was maintained near 650'F for catalytic operation 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 Due to the tight soil conditions and I limited screen interval, a vacuum potential near 20 inches of water was maintained on wells VW I, VW2, VW3 and VW5 in order to achieve minimal flow from these wells Organic vapor was measured at concentrations as high as 532 ppm in the extracted air streams (VW5) The measurements for each well are shown in Table 7 I34 ANALYTICAL RESULTS OF SOIL VAPOR SAMPLES • TPH-g was detected in the soil vapor samples at concentrations of 200 gg/l and 160 gg/l Soil vapor I Advanced GeoEnvironmental,Inc I