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11 January 2005 AGE-NC Project No. 01-0887 Page 2 of 3 with occasional detections in MW-2. The vertical extents of impacted soil and ground water have not yet been defined at the site. Laterally, the southern extent of impacted ground water may be defined in well MW-4. Site history and findings from previous investigations,including current and historical ground water elevation data and analytical results, are detailed in the AGE-prepared Quarterly Report - Fourth Quarter 2004, dated 27 December 2004. SCOPE OF WORK AGE proposes to advance five paired CPT soil borings to collect soil textural data and soil and ground water samples. One of the paired borings at each location will be a cone penetrometer test to help determine lithology and flow units; the second, adjacent boring will be advanced to collect water and soil samples at key water-bearing zones. The borings will be advanced at the following locations (Figure 2): • Near monitoring well MW-1, in the area of greatest ground water contamination, to define the vertical extent of impacted soil and ground water(CPT-2); and • On the west side of the former office building southwest of well MW-2(CPT-3);east of well MW-3 (CPT-1); on the opposite side of Clifton Court Road to the north (CPT-4); and southeast of well MW-4 to help delineate the lateral extent of impacted soil and ground water (CPT-S). CPT boring locations are based on current and historic ground water analytical data collected from the monitoring wells on-site. AGE believes that the proposed borings CPT-1 through CPT-4 are placed such that the lateral extent of petroleum hydrocarbon contamination will be defined. The borings will be advanced to a nominal depth of 100 feet bsg, as AGE believes that the total CPT depth of 50 feet bsg proposed in the AGE-prepared Additional Site Assessment Work Plan,dated 07 October 2004,may be insufficient to define the vertical extent of contamination clue to the presence of 1,2-DCA at the site. If petroleum hydrocarbon odor is detected in the water sample collected at total depth, additional water samples will be collected from deeper, approximately 20-foot depth intervals until a depth is reached where no hydrocarbon odor is detected; in addition, subsequent CPT borings will be advanced to the non-detect depth determined from the initial CPT borings. Field procedures were described in the above-referenced Additional Site Assessment Work Plan;the precise boring locations may be adjusted based upon access agreements with the property owner north of Clifton Court Road and the locations of underground utilities. AGE will notify the San Advanced GeoE nvi ron mental,Inc.