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i 07 March 2003 <br />' AGE-NC Project No 95-0141 <br /> Page 8of10 <br />' Wells MW-3,MW-.-;,MW-7,MW-8A through MW-12A and EX-1 were used to determine grould <br /> water flow direction and gradient for shallow ground water The shallow ground water was inferred <br />' to flow generally toward the southeast, at a gradient of 0 004 foot/foot Figure 5 illustrates the <br /> contoured shallow ground water elevations as measured on 28 October 2002 <br />' Wells MW-6 and MW-8B through MW-12B were used to determine ground water flow direction <br /> and gradient for deep ground water The deep ground water was inferred to flow generally toward <br /> the southeast, at a gradient of 0 007 foot/foot Figure 6 illustrates the contoured deep ground water <br />' elevations as measured on 28 October 2002 <br /> 3 6 ANALYTICAL RESULTS FROM GROUND WATER SAMPLES <br /> The analytical results of the ground water samples were as follows <br /> • TPH-g was detected in ground water samples collected from wells MW-3,MW-6, MW-813, <br /> MW-9B, MW-11B and EX-1 TPH-g concentrations ranged from 80 µg/1 in MW-11B to <br /> 150,000 µg/1 in EX-I <br /> One or more BTEX compound were detected in samples MW-3,MW 6,MW-8B, MW-9B, <br /> MW-11B and EX-I at concentrations as high as 11,000 µg/1 benzene, 36,000 pg/1 toluene, <br /> I4,000 µg/1 ethylbenzene and 20,000 gg/1 xylenes (EX-1) <br /> Fael oxygenates were not detected in the ground water samples collet, :d from `he site <br /> ® 1,2-DCA was detected in ground water samples collected from all wells except MW-I OA/B <br />' and MW-12A/B Concentrations ranged from 0 50 µg/1 (MW-11A) to 410 µg/1 (EX-1) In <br /> addition, EDB was detected in the ground water sample collected from well EX-1 at a <br /> Iconcentration of 65 gg/1 <br /> The areal extent of TPH-g and 1,2-DCA impacted shallow and deep ground water is illustrated on <br /> Figures 7 and 8,respectively Laboratory results ofwater samples analyzed are summarized in Tables <br /> 3 and 4 The Iaboratory reports for the quarterly monitoring event(MAI Laboratory IDs 0210536-001 <br /> through 0210536-015) QA/QC reports and chain-of-custody form are included in Appendix G <br /> I <br /> 4.0. SUMMARY AND CONCLUSIONS <br /> I The findings of the fourthuarter site investigation events include the following <br /> q g g <br /> • Generally, sand, silty sand and gravelly sand were encountered at depths between 20 and 31 <br /> . feet bsg, 48 and 74 feet bsg and 113 and 117 feet bsg Fine grained, silt, silty clay, clayey <br /> silt,sandy silt and clay were observed at all other depths The computer generated boring log <br /> for CPT-01 is included in Appendix B <br /> Advanced GeoEnvironmental,Inc <br /> I <br />