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Appendix A AGE NC Project No 99-0570 Page 3 of 5 I On 09 December 2003, three soil bonngs (CPT-1, CPT-2, and CPT-3) were advanced on-site utilizing cone penetrometer testing(CPT)technology to a total depth of approximately 110 feet bsg At each boring location, lithologic data was collected from the initial CPT boring, an immediately I adjacent twin boring was then advanced to collect grab ground water samples CPT-1 was sampled between 55 feet and 60 feet bsg and between 80 feet and 84 feet bsg, CPT-2 was sampled between 55 feet and 60 feet bsg,between 89 feet and 94 feet bsg, and between 110 feet and 114 feet bsg, and CPT-3 was sampled between 55 feet and 60 feet bsg,between 85 feet and 90 feet bsg, and between 110 feet and 114 feet bsg ' Three limited excavations in the northeast edge of the former dispensers removed an estimated 150 cubic yards of significantly petroleum hydrocarbon-impacted soil The total depth of the three excavations was 8 feet bsg The sidewalk and floor of the excavations EXE2 and EXE3 exposed hydrocarbon-impacted soil Hydrocarbon-stained soil was not apparent in the final sidewalls and floor of excavation EXE 1 Soil samples were collected from the excavation side walls at a depth of 8 feet bsg and a soil sample was collected from the floor of the southernmost excavation (EXE I)at a depth of 8 feet bsg The analytical data indicated that the highest concentrations of TPH-g were in excavations EXE2 and EXE3 at the northeastern edge of the dispenser area,near well MW-2 TPH-g was detected in the eastern soil sample from excavation EXE2 at a concentration of 17,000 mg/kg ' TPH-g was also detected in the soil sample from the southern edge of excavation EXE3 at a concentration of 11,000 mg/kg BTEX compounds were detected at concentrations as high as 2,300 mg/kg The highest concentration of benzene, 15 mg/kg, was detected in the eastern sample from excavation EXE2 Fuel additives were detected in samples from excavations EXE2 and EXE3 TPH-d was detected in the soil samples from EXE2 and EXE3, which were also impacted with ' TPH-g and BTEX compounds Low concentrations ofTPH-d were detected in two soil samples from EXEI The stockpiled soil was impacted by low to moderate concentrations of petroleum hydrocarbons and fuel additives tSoil from B-1,B-2, and B-7 at 15 feet bsg had low concentrations of hydrocarbons,while soil from B-1,B-6, and B-7 at 10 and 15 feet, as well as B-2 at 10, 15,and 20 feet bsg had low concentrations V4, of fuel additives (MTBE) Hydrocarbon-impacted ground waterB a�dgtt cted at B-1,B-6,B-7, and Yl2q�G B-8 and MTBE was detected in grab ground water samples from - and V-7 MTBE was detected by EPA method 8260 in all grab ground water samples up to 150 µg/1 (B-6) r HYDROGEOLOGIC MODEL Based on the CPT results, AGE has assigned names to four informal zones a vadose (unsaturated) zone and three hydrogeologic units Advanced GeoEnvironmentai,Inc