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Srs° %we 30 March 2012 AGE-NC Project No. 97-0312 Page 3 of 8 • A four-inch diameter, high vacuum SVE well (VW-5), screened between 15 and 30 feet bsg, will be located in the former GASOLINE tank pit, near borings B12 and B17; • A four-inch diameter, high vacuum SVE well (VW-4), screened between 15 and 30 feet bsg, will be located in the former dispenser area, near boring B10 and south of vapor well VW-1; • A four-inch diameter, high vacuum SVE well (VW-6), screened between 15 and 30 feet bsg, will be located near boring B15; • A four-inch diameter, high vacuum SVE well (VW-9), screened between 25 and 45 feet bsg, will be located near the source area at MW-7; • A four-inch diameter, high vacuum SVE well (VW-10), screened between 25 and 45 feet bsg, will be located near the former GASOLINE tank pit and boring B12; and • A four-inch diameter, high vacuum SVE well (VW-11), screened between 25 and 45 feet bsg, will be located near the source area at MW-9. Proposed high vacuum SVE well locations are depicted in Figure 2; general lithology beneath the site is depicted in cross sectional view 8-8'in Figure 3; and the lateral extent of hydrocarbon-impacted soil is depicted in Figure 4. The proposed SVE screen intervals are located in areas of known diesel and gasoline- impacted soil and down-gradient(northeast)in areas of known petroleum-impacted ground water. The wells are proposed at locations suitable for site remediation. Additional remediation well locations will be evaluated based on the findings of the initial well installation (soil samples) and remediation progress. Initially, soil borings for SVE wells VW-4 through VW-8 will be advanced to depths of 30 feet bsg, and the boring for wells VW-8 through VW-11 will be advanced to a depth of 45 feet bsg; however,total depths of each borings and/or screen intervals may be adjusted in the field and will be based on field observations and field screening using an organic vapor monitor (OVM). Total depths of borings may vary according to geologic conditions encountered during drilling. The proposed SVE wells will be advanced utilizing a truck- mounted, hollow stem drill rig equipped with 10-inch diameter hollow-stem augers. Following completion of the seven soil borings, the high vacuum SVE wells (VW-4 through VW-11)will be installed into the bore holes. Based on soil and ground water data collected during the previous site investigations, AGE proposes the installation of the high vacuum SVE wells in the areas of the highest reported concentrations of adsorbed soil contaminants (i.e., the former UST areas and pump islands). Procedures for well installation are presented in Sections 3.1 and 3.2, respectively. Advanced GeoEnvironmental,Inc.