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a t 19 November 2009 AGE-NC Project No. 02-0950 Page 5 of 13 of 54 feet bsg, 72 feet bsg and 100 feet bsg did not detect any constituents of concern. Analytical results of grab ground water samples are summarized in Table 3.Boring logs are presented in Appendix C.A report of findings(Additional Site Assessment Report, dated 01 November 2005) was prepared by AGE and submitted to the EHD and RWQCB. • On 21 July 2005,two soil borings(MW-4 and MW-5)were advanced on-and off-site to total depths of 35 feet bsg. Soil boring MW-4 was located on-site, east of the former UST area; soil boring MW-5 was located off-site, south-southwest of the former UST area. The pilot borings for MW-4 and MW-5 were completed as 2-inch diameter ground water monitoring wells utilizing PVC well casing and screened between 15 feet and 35 feet bsg. Laboratory analysis of soil samples did not detect any constituents of concern.Analytical results of soil samples are summarized in Table 2. Boring logs are presented in Appendix C. A report of findings (Additional Site Assessment Report, dated 01 November 2005) was prepared by AGE and submitted to the EHD and RWQCB. • On 19 March 2008, two soil borings (MW-6 and MW-7) were advanced on-site to total depths of 30 feet bsg. Soil boring MW-6 was located southeast of the former UST area; soil boring MW-7 was located adjacent the former UST area. The pilot borings for MW-6 and MW-7 were completed as 2-inch diameter ground water monitoring wells utilizing PVC well casing and screened between 10 feet and 30 feet bsg.Laboratory.analysis of soil samples did not detect any constituents of concern. Analytical results of soil samples are summarized in Table 2. Boring logs are presented in Appendix C. A report of findings (Well Installation Report, dated 19 June 2008)was prepared by AGE and submitted to the EHD and RWQCB. General lithology, selected soil sample locations, and the estimated extent of impacted soil beneath the site is depicted in cross sectional view in Figures 4 through 7 and in plan view in Figure 8. 2.4. GROUND WATER MONITORING EVENTS Between October 2003 and May 2009, twenty-three (23) ground water monitoring events were performed at the site to monitor dissolved petroleum hydrocarbon concentrations in ground water and to characterize ground water flow direction and gradient on the site. Since initiation of the ground water monitoring program,ground water elevations have ranged from approximately 6 to 12 feet below the North American Vertical Datum (NAVD) and depths to ground water have ranged from approximately 14 to 20 feet below the tops of the well casings (btoc). Based on the above monitoring events, ground water flow direction at the site was inferred to be generally towards the northeast and east,at low hydraulic gradients ranging between 0.002 ft/ft and 0.022 ft/ft. However, between December 2005 and May 2009, ground water flow direction at the site was inferred to be generally towards the southeast at low hydraulic gradients ranging between 0.002 ft/ft and 0.01 ft/ft. Ground water elevation data is summarized in Table 5. Ground water elevation figures depicting Advanced GeoEnvironmental,Inc.