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19 October 2010 AGE-NC-Project NO. 02-0962 Page 2 of 3 (MTBE): However, MTBE has not been reported ir ground water samples collected from well MW-4 since March 2007; additionally,TPHLg h ave not been reported in well MW-4 for six consecutive monitoring events between M 3rch 2007 and June 2008. A low concentration of TPH-g-and total petroleum hydrocarbons quantified as diesel were reported in well MW-4.during the final ground wat r sampling event in September 2008. Analytical results of ground water.samples are summarized in Table 2. AGE is proposing to drilkoutiwell MW-4; additionally, AGE is proposing to destroy wells MW-1 through MW-3, and MW-5 through MW- -by pressure grouting techniques, in accordance with the EHD Standards For Well Construction and Destruction. PROCEDURES As required by EHD permitting, a health and safet f plan will be prepared in accordance with Occupational Safety and Health Guidance Man jai forHazardous Waste Site Activities (National Institute for Occupational Safety and He Ith Administration, U.S. Coast Guard and U'S.Environmental Protection Agency,.1986).Priortodrilling 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 i the well will be removed. Well MW-4 will be drilled-out-to the total depth of the well, utilizing 8-Inch diameter hollow- stem augers.All original well construction materials will be removed (including well casing, screen, filter pack, and annular seal) to ensure th t 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 orasphalt, depending on the surrounding surface material. Well boxes and caps will be removed to expose the casings of wells MW-1 through MW-3 and MW-5 through MW-7. The casings will be lifted out:of the borehole, and the bottom plug punched:out•:using steel rods. The casings will then be used as a tremmi pipe for grouting procedures. A ratio of-six gallons of.water for every 94-pound sack of portland cement (grout) will be utilized in preparation of th grout mixture. If the casings are not., lifted out of the borehole intact,then the well will be gilled-out to the total depth of the well, and destroyed as described above. Following gr uting procedures, the casings will be removed, and the wells will then be over-drilled t approximately 5 feet below surface grade (bsg) using 8-inch diameter hollow stem au ers. The remaining borehole will then Advanced GeaEnv1ronmenta4 Inc.