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titr V • 30 January 2004 AGE-NC Project No 01-0865 Page 5 of 7 below surface grade,two borings encountered refusal at their respective total depths A total of eleven ground water samples were submitted for laboratory analysis • On 22 and 23 December 2003, AGE advanced four soil borings at the site Pilot borings MW 11 through MW 14 were completed as ground water monitoring wells using two-inch diameter PVC casing with 0 020-inch slotted screen installed from approximately 3 feet to 13 feet bsg in borings M W 12 through MW 13 and from approximately 70 feet to 80 feet bsg in boring MW11 with blank casing extended to the surface A total of 15 soil samples were submitted for laboratory analysis AGE is currently preparing a detailed investigative report further describing the assessment activities briefly described in this section 4 2 GROUND WATER MONITORING Four monitoring events took place at the site during year 2003, three utilizing 10 monitoring wells and one utilizing 14 monitoring wells, all four events incorporated four surface water samples • 4 2 1 Ground Water Flow Direction and Gradient The ground water flow direction fluctuated from east-northeast to southeast during the course of the year under average gradients ranging from 0 027 ft/ft to 0 250 ft/ft The ground water flow inferred from the deep-screened(50 feet to 60 feet and 70 feet to80 bsg)wells fluctuated from east-northeast to east-southeast but under a much shallower average gradients ranging from 0 001 fl/ft to 0 005 fl/ft 4 2 2 Analytical Results of Ground Water Samples MTBE, TPH-g, BTEX compounds, TAME and TBA were detected at the following maximum concentrations in the groundwater samples over the past year 71,000 µg/1 MTBE (MW-2, June 2003), 80,000 gg/1 TPH-g (MW-2, June 2003), 140 µg/1 benzene (MW-6, March 2003), 800 µg/1 toluene (MW-6, March 2003), 60 µg/1 ethylbenzene (MW-6, March 2003), 644 µg/1 total xylenes (MW-4, September 2003), 320 µg/1 TAME (MW-2, June 2003) and 1,300 µg/1 TBA (MW-2, September 2003) No other analytes were detected at or above laboratory detection levels During year 2003, MTBE and TPH-g concentrations remained relatively stable in monitoring well MW-5 increased markedly in wells MW-2,MW-3 and EW-1 during the second quarter and declines in the third quarter, and increased markedly in MW-4 and MW-6 during the third quarter with a decline in the fourth quarter Benzene remained relatively stable at low to non-detectable Advanced GeoEnvironmental,Inc