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t , . • • 07 June 2011 AGE-NC Project No. 01-0839 Page 2 of 3 performed at the site to monitor dissolved petroleum hydrocarbon concentrations in ground water. Elevated concentrations of petroleum hydrocarbons were detected in ground water monitoring wells MW-1 through MW-4. Analytical results of ground water samples are summarized in Table 3. AGE proposes to drill out wells MWA through MW-4 and VW-1 through VW-6, and destroy well MW-5 by pressure grouting techniques.The wells will be destroyed in accordance with the EH Standards For Well Construction and Destruction. Remediation piping connecting soil vapor extraction wells VW-1 through VW-6 will be left in place. Additionally, AGE proposes to resurface areas that have been trenched for remediation piping (Figure 2). PROCEDURES As required, a health and safety plan will be prepared in accordance with Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities(National Institute for Occupational Safety and Health Administration, U.S. Coast Guard and U.S. Environmental Protection Agency, 1985). Prior to drilling activities, each proposed drilling location will be clearly marked and an utility clearance obtained through Underground Service Alert. Prior to destruction activities, wells will be checked for total depth and integrity using a Solinst water level meter. Any obstructions found in the well will be removed. Wells MWA through MW-4 and VW-1 through VW-6, will be drilled-out to one foot deeper then the total depths of the wells utilizing 8-inch diameter hollow-stem augers. All original well construction materials will be removed (including well casing, screen, filter pack, and annular sea]) to ensure that no residual contamination is sealed within the abandoned borehole. The remaining borehole will be backfilled to surface grade with neat cement and covered with concrete or asphalt, depending on the surrounding surface material. The well box and cap will be removed to expose the well casing of well MW-5. The well head will be fitted with a pressure tight adapter connected to a hose extending from a grout mixer. A thick grout mixture will be pumped into the well casing under approximately 5-15 pounds per square inch (psi) of pressure. The well will then be over-drilled to approximately 3 feet below surface grade (bsg) using 8-inch diameter hollow stem augers. The top 2.5 feet of the well casing will then be cut and removed and grout will be used to fill the boring to approximately 0.5 feet above the top of the well casing. The remaining borehole will be backfilled to surface grade with neat cement and covered with concrete or asphalt, depending on the surrounding surface material. Advanced GeoEnvironmen[al,Inc.