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,. 05 July 2002 AGE-NC Project No. 98-0520- . Page 5 of 7 3.3. ANALYTICAL RESULTS OF SOIL SAMPLES A total of three soil samples were analyzed for TPH-g,TPH-d,TPH-mo,BTEX,MTBE,EDB, 1,2- DCA and the suite of five fuel oxygenates. No analytes were detected at or above laboratory reporting limits in the soil samples analyzed. 1 Analytical results of soil samples are summarized in Table 2.The laboratory reports(CTEL Lab.I.D. No. 0202-101-1 through 0202-101-3), quality assurance' and.quality control (QA/QC) report and 1 chain-of-custody forms are included in Appendix E. 3.4. GROUND WATER ELEVATION AND GRADIENT The elevation of ground water in each well was calculated by subtracting the depth to ground water ' from the surveyed casing elevations (Table 1). Depths to ground water ranged from 18.20 feet to 19.33 feet below the tops of the well casings. Ground water elevations at the site ranged from 1 17.13 feet (MW-9) to 17.87 feet (MW-10) above mean sea level. The ground water flow direction was determined using ground water elevation data. The ground water table underlying the site formed a trough-like depression,with the base of the trough plunging north-northeast under an average gradient of 0.001 ft/ft. The western limb of the trough flows northeast;the eastern limb's flow direction is northwest.At such a low gradient,.small measurement ' variations can greatly affect the inferred flow direction. Figure 4 illustrates the contoured ground water elevations as measured on 28 February 2002. 1 3.5. ANALYTICAL RESULTS OF GROUND WATER SAMPLES• TPH-g,was detected in the water samples collected from wells MW-1 through MW-5, MW-8 and ' MW-10 at concentrations ranging from 420 micrograms per liter(µg11) in MW-8 to 11,000 pg/fin MW-5 (Figure 5): Various BTEX compounds were detected in•all of the water samples analyzed, except the water samples collected from wells MW-7 and MW-9. Toluene was detected in,samples from MW-2, MW-3, MW-6 and MW-8 at a maximum concentration of 2.9 pg/1 (MW-3). The maximum ' ethylbenzene and xylene concentrations were detected in the sample from MW.-5 at 890µgjand 960 µg11, respectively. All concentrations of these analytes: Were below California's Maximum Contaminant Levels for drinking water. Advanced CeoEnvironmental,Inc.