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I 10 December 2001 AGE-NC Project No 95-0141 ' Page 3 of 5 ' 3 1 GROUND WATER ELEVATION AND GRADIENT The average ground water elevation of the seven shallow ground water monitoring wells on ' 12 November 2001 was approximately 13 3 feet below mean sea level(msl),with the average depth of water at 21 0 feet below casing tops The ground water table occurred within the screened intervals of wells MW-7 and MW-8 During the November 2001 monitoring event, ground water ' was between 7 82 and 9 38 feet above the screened intervals in monitoring wells MW-1 through MW-5 Therefore, the five ground water monitoring wells 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 ground water table occurred approximately 39 feet above the screened interval of the deep well MW-6 ' Based on data collected during the November 2001 monitoring event, ground water appears to be ridged near the former UST area (Figure 3) The gradient was inferred to be flowing toward the south-southeast with a gradient of 0 004 ft/ft east of the former UST area 1 • 3 2 ANALYTICAL RESULTS FROM GROUND WATER SAMPLES ' Monitoring wells MW-1 through MW-8 were sampled on 12 November 2001 The analytical results of the ground water samples were as follows ' TPH- was detected m ground water samples collected from monitoring wells MW-1, g �' p MW-2, MW-3, MW-6 and MW-7 TPH-g concentrations ranged from 61 micrograms per ' liter (µg/1) In MW-7 to 140,000 µg/l in MW-1 Benzene, toluene, ethylbenzene and total xylenes were detected in the ground water samples collected from monitoring wells MW-1, MW-2, MW-3 and MW-6 at concentrations as high as 10,000 µg/l (MW-1), 25,000 µg/1 t (MW-1), 3,700 µtg/l (MW-1) and 16,000 µg/l (MW-1), respectively TBA was detected in the sample collected from MW-3 at a concentration of 29 µg/l DIPS, ' MTBE, ETBE and TAME were not detected in the ground water samples collected from the site ' 1,2-DCA was detected in ground water samples collected from MW-1, MW-2, MW-3, MW-5,MW-6,MW-7 and MW-8 Concentrations ranged from 4 7 µg/1(MW-5)to 280 µg/1 (MW-1) EDB was in the ground water sample collected from MW-1 at a concentration of ' 5 1 µg/1 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 83462 through • 83469) QA/QC reports and chain-of-custody form are included in Appendix C 1 Advanced GeuEnviron ental,Inc 1