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d 28 August 2009 AGE-NC Project No. 04-1173 Page 2 of 4 system piping is included as Figure 3. The boring locations are shown on Figure 4. PROCEDURES Prior to mobilization, the area of excavation was clearly marked and a utility clearance obtained through Underground Service Alert. KCP,a general engineering contractor for service station maintenance and repair was present at the site during all soil sampling activities. Due to unavailability of as-built plans of the site UST system,a 3-foot by 4-foot rectangle was saw- cut in the concrete surface and removed between Dispenser islands 15 and 16 to determine the exact location of the UST piping. The concrete was approximately nine-inches thick. KCP removed the pea gravel and exposed the piping.Based upon KCP's determination of the location of the lines and Mr.Jutla's direction,9-inch diameter concrete cores were cut adjacent to diesel dispenser locations DD-11 through DD-17 on the south and west side of the respective islands for soil sampling purposes. After the 9-inch,diameter concrete cores were cut and removed,AGE inserted a two-inch diameter PVC pipe through the cored concrete at an approximate angle of 61 degrees to the surface through the pea gravel fill material of the UST system piping.A wet-dry vacuum was attached to the 2-inch PVC pipe and pea gravel was vacuumed from sub-slab while advancing the PVC pipe through the pea gravel to native material nearly directly beneath each dispenser island. Once native soil material was reach with the two-inch diameter PVC pipe, a 1.5-inch diameter Geoprobe®macrocore®soil sampler attached to 1.125-inch steel rods and loaded with four 1-inch diameter stainless steel sleeves was placed through the conduit(PVC pipe)to the depth of the native soil material. The soil sampler was advanced manually into the native soil material using a steel fence post driver. The sampler was then opened and advanced approximately eight inches into the native soil material.The sampler was then retracted and the soil sleeves removed.The collected soil samples were preserved by covering both ends of the stainless steel sleeve with Teflon®sheets,caps and sealing with tape. Each preserved sample sleeve was labeled with soil boring location, depth, time, date and sampler's initials and was stored in a chilled container under ice. Due to the grading of the trench containing the UST piping,borings B-11 and B-12 were advanced to approximately 6 feet below surface grade(bsg),while borings B-13 through B-17 were advanced to approximately 5 feet bsg in order to reach first encountered native soil material. As overseen by a SJCEHD inspector,each boring was allowed to be naturally backfilled with all pea gravel material removed during the soil sampling activity with the except of boring B-11.A portion Advanced GeoEnvironmental,Inc.