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' 28 August 2000 AGE-NC Project No. 98-0481 Page 3 of 8 No benzene, toluene, ethylbenzene, total xylenes (BTEX), total petroleum hydrocarbons as diesel (TPH-d)or total petroleum hydrocarbons as gasoline(TPH-g)were detected in soil samples analyzed (Tablet). Soil samples were not analyzed for fuel oxygenates or lead. During drilling activities, groundwater was not encountered in any of the borings. In September 1998,AGE attempted to conduct site assessment activities using Geoprobe direct-push technology. However, refusal was encountered in each soil probe boring at depths ranging from 8 to 10.5 feet below surface grade (bsg). Geoprobe refusal was apparently due to encountering hardpan, which prevented investigation to the proposed depth of 30 feet bsg. During the Geoprobe investigation, one soil sample was collected from probe boring B-Ig at a depth of 9.5 feet bsg. Soil probe boring B-I g was advanced in the approximate area of UST removal soil sample S-4-FDw, located at the former west fuel dispenser location (Figure 2). There were no reported detections of benzene, toluene, ethylbenzene, total xylencs (BTEX), total petroleum hydrocarbons as diesel (TPH-d),total petroleum hydrocarbons as gasoline(TPH-g),di-isopropyl ether(RIPE),ethyl tertiary- butyl ether (ETBE), methyl-tertiary butyl ether (MTBE), tertiary-amyl methyl ether (TAME), tertiary-butanol (TBA), or total lead in soil sample B-1-9.5' (Table 2). The remaining six probe borings B-1 a through B-1 f were not sampled. Results of the initial site assessment work were presented in a letter report to the PHS-EHD, dated 04 December 1998. The letter report included the recommendation that the preliminary site assessment be continued utilizing holIow-stem auger drilling techniques. On 28 January 1999, the preliminary site assessment was continued using a hollow-stem auger drill rig to advance soil borings SB-1 and SB-2. One soil boring, SB-1 was completed at the former location of the eastern fuel dispenser corresponding to UST removal soil sample S-4-Me (Figure 2). Soil boring SB-1 was advanced to a depth of 31 feet bsg. There were no reported detections of BTEX, TPH-d,TPH-g,DIPE, ETBE,MTBE,TAME, or TBA in the soil samples collected from soil boring SB-1 at depths of 11 feet bsg, 26.5 feet bsg, and 31 feet bsg. Total lead was detected only in soil sample SB-1-11', and was present at a concentration of 4.7 mg/kg (Table 2). The soil sample analytical results from soil boring SB-1 indicated that the relatively low levels of petroleum hydrocarbons previously detected in soil sample S-4-FDe appear localized and have not migrated. significantly. During site assessment activities, soil boring SB-2 was attempted at the former location of the western fuel dispenser corresponding to UST removal soil samples S-4-FDw and S-8-E. However, during the advancement of soil boring SB-2, an active gasoline(super)product line for the operating service station was inadvertently encountered and ruptured. The active product line had not been accurately located on the engineer's as-built construction plan. Soil boring SB-2 could not be advanced following the product line rupture. It is estimated that the rupture of the product line resulted in the release of as much as 10.56 gallons of gasoline. Calculation of the volume of the release is presented below. Advanced GeoEnvironmentul,Inc-