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� u 26 April 2011 AGE-NC Project No. 03-1100 Page 5 of 6 4.3. LABORATORY RESULTS OF GROUND WATER SAMPLES TPH-g were detected in the samples collected from well OW-4 at a concentration 100 micrograms per liter (pg/1). No other constituents of concern were detected from the ground water samples collected. The analytical results from ground water samples collected on 30 March 2011 are summarized in Table 3. Monitoring well field logs are included in Appendix H. The laboratory report (CTEL I.D. No. 214-1103225)and chain-of- custody forms are included in Appendix I; analytical results have been uploaded to GeoTracker,and were referenced by GeoTracker under confirmation number 9075437188. 5.0 SUMMARY/CONCLUSIONS The results of the January 2011 well installation and the March 2011 limited ground water sampling event are as follows: • On 26 and 27 January 2011, ten ozone injection wells (OW1 through OW10)were installed at the site. Injection wells were single completed, using 1-inch diameter, 50-micron sparge point diffusers installed at various depths between 12 feet and 15 feet bsg (Appendix D). • Excavation gravels were generally encountered at wells OW7 through OW-10 from surface grade to maximum depths of 7 feet bsg. Silty sands and clays were generally encountered from 11 to 15 feet bsg. Samples collected at both intervals contained either slight or moderate hydrocarbon-like odors. • A total of four soil samples were submitted for analysis. BTEX constituents were detected in two of the four samples at maximum concentrations of 0.012 milligrams per kilogram (mg/kg) benzene, 0.022 mg/kg ethylbenzene and 0.030 mg/kg total xylenes (OW4-14). • On 30 March 2011, depth to ground water ranged between 6.69 feet (OW3) below the top of well casing (btoc) and 7.22 feet (OW6) bloc. • On 30 March 2011, ground water samples were collected from wells OW3, OW4, OW6, and OW7. TPH-g were only detected in the samples collected from OW4 at a concentration 100 pg/I. However, ground water levels were 4.78 feet to 6.31 feet above the screen intervals of wells OW3, OW4, OW6, and OW7 and therefore may not be truly representative of shallow ground water conditions. Advanced GeoEnvironmental,Inc.