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1 02 January 2002 AGE-NC Project No. 95-0185 Page 4 of 5 ' Figure 3. 3.2, GROUND WATER ANALYTICAL RESULTS TPH-d was detected in ground water samples collected from each monitoring well (MW-1 through ' MW-4) at concentrations of 5,500 micrograms per liter (gg/l), 3,200 pg/l, 520 µg/l, and 260,000 gg/l, respectively. TPH-g was detected in ground water sample MW-1 and MW-4 at concentrations of 150 �tg/l and 280 gg/l, respectively. Toluene was detected in the ground water ' sample from well MW-i at concentrations of 0.63 gg/l. Current and previous analytical results are summarized in Tables 2 and 3. The laboratory report(MAI ' Laboratory T.D. Nos. 82239 to 82242), quality control and quality assurance data (QA/QC) and chain-of-custody form are included in Appendix B. TPI-d was detected in grab ground water samples from probe borings P 12A/B through P 13A/B at concentrations of 370 gg/l, 130 gg/l, 550 µg/l and 140 gg/l, respectively. Benzene was detected in sample P 13A at a concentration of 0.64gg/l. The other BTEX and fuel additives were not detected lie in the grab ground water samples. The analytical results of these samples are summarized in Table 4. The laboratory report (MAI ' Laboratory I.D. Nos. 82243 to 82246), cliain--of-custody and QA/QC report are included in Appendix C. A cross section depicting the depth of the grab ground water samples is shown in ' Figure 4. ' 4.0. CONCLUSIONS Based on the data collected during this monitoring period, AGE concludes: 1 • Ground water flow at the site was toward the southeast at hydraulic gradient was determined to be 0.0004, which is nearly flat. The hydraulic gradient suggests that ground water has a ' very slow flow rate. The concentrations of TPH-d in samples from wells have increase since the last monitoring event,=except for_monitaring well= • BTEX compound were generally not detectable, except for a trace concentration of toluene in the sample from well MW-1. 1 TPH-d was detected in the grab ground water samples collected from 40 to 50 feet bsg. The presence.of TPH-d at low concentrations_ at that depth shows that the water zone between ' the water table and 50 feet bsg beneath the site is impacted. The low concentrations of contaminants detected, however, indicates minor migration of dissolved TPH-d to the depths ' Advanced GeoEnviro=eutaL Inc.