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. 23 March 2001 AGE-NC Project No 97-0343 Page 6 of 7 ' ground water samples collected from morutonng wells MW1, MW2 and MW3 at concentrations of 710,ugll, 2,700µg/1 and 380µg/1, respectively ' Benzene was detected in the ground water samples collected from MW1 through MW7 with the exception of MW4 at concentrations ranging from 0 61 ktg/l in MW5 to 16 4g/1 in MW2 Toluene ' and xylenes were detected in the samples collected from MW 1 through MW7 with the exception of MW4 at concentrations as high as 550,ug/l and 1,800,ug/1 (MW2), respectively Ethylbenzene was detected in the samples collected from MW1, MW2 and MW3 at concentrations as high as 310 kcg/1 ' Fuel oxygenated compounds were not detected above laboratory reporting limits in the ground water analysis ' The analytical results of water samples collected in January and February 2001 are summarized on Table 3 The laboratory reports(AAL Order No A01012607 and MAI Lab I D No 60023-60026), QA/QC report and chain-of-custody form are included in Appendix F I 4.0. SUMMARY AND CONCLUSIONS ' • Based on the data collected from the site, AGE finds ' • Ground water flow at the site on 25 January 2001 was inferred to be toward the west at a gradient of 0 001 feet/feet Groundwater elevations at the site decreased an average of 0 19 feet since the October 2000 monitoring event ' • Generally poorly graded sand with silt was encountered from 15 feet bsg to 30 feet bsg, silty sand was encountered from 30 feet bsg to 45 feet bsg and silty clay was encountered from ' 45 to 60 feet bsg • TPH-g, TPH-d, BTEX, EDB, 1,2-DCA and the five fuel additives were not detected at or ' above laboratory reporting limits in the soil samples collected from monitoring well pilot borings MW4 through MW7 The lateral and vertical extent of petroleum hydrocarbon- impacted soil has been defined(Figures 6 and 7) ' • Concentrations of dissolved TPH-g, TPH-d and BTEX compounds increased in samples from wells MW2 and MW3 and decreased in sample MW1 compared to the October 2000 monitoring event TPH-g and TPH-d were not detected at or above laboratory reporting ' limits in ground water samples collected from MW4 through MW7 Low concentrations of benzene, toluene and xylenes were detected in wells MW5, MW6 and MW7 Fuel ' oxygenates were not detected in the ground water samples collected at the site The lateral extent of the fuel-impacted ground water has been fairly well defined The current TPH-g and • TPH-d isocontours are depicted on Figures 8 and 9 1 Advanced GeaEnvirnnmental,Inc 1