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1.0 Ime Tank 2 was excavated and removed by SEMCO on December 20, 1989. There is no information regarding the condition of the tank on the Underground Tank Closure/Abandonment Inspection form filed by Charles Hunt. However, according to SEMCO, no obvious problems with the tank were observed. According to Mr. Hunt, 15 cubic yards of soil were removed from the tank excavation, which was 32 feet by 15 feet by 13 feet in dimension. Two soil samples were collected by SEMCO on December 20, 1989, after the tank was removed, in accordance with State and SJCPHS guidelines. One sample was collected at a depth of 17 feet at the north end of the former tank. The other sample was collected at a depth of 17 feet at the south end of the former tank. Both samples were analyzed for VOCs by USEPA Method 8240. The results of the analyses are presented in Table 1. As shown in Table 1 , extremely low concentrations of acetone (0.0199 milligrams per kilogram [mg/kg]) and xylenes (up to 0.0064 mg/kg) were reported in the soil samples collected from beneath Tank 1. Similarly, very low concentrations of acetone (0.073 mg/kg), toluene (0.0083 how mg/kg), ethylbenzene (0.0231 mg/kg), styrene (0.0362 mg/kg), and xylenes (0.0134 mg/kg) were reported in soil from beneath the former pipeline. VOCs were not detected in the soil sample collected from beneath the south end of Tank 2. Concentrations of acetone (930 mg/kg), 2-butanone (6.0 mg/kg), 4-methyl-2-pentanone (0.6 mg/kg), ethylbenzene (0.192 mg/kg), styrene (0.6 mg/kg), xylenes (0.151 mg/kg), dimethyl-methyloxime-cyclohexene (0.5 mg/kg), and benzaldehyde (0.3 mg/kg) were reported in the soil sample collected beneath the north end of Tank 2. On October 18, 1990, Augeas Corporation (Augeas) drilled four soil borings through or adjacent to the former Tank 2 excavation. Borings SB-1 and SB-2 were drilled through the north and south ends of the former excavation, respectively. Borings SB-3 and SB-4 were drilled just outside the north end of the former excavation. Boring SB-3 was located east of 6W the former excavation while boring SB-4 was located to the west. All four borings were drilled to total depths of 17 feet. Soil samples for chemical analysis were collected at depths of 15 feet from borings SB-2 through SB-4. A soil sample for chemical analysis was collected at a depth of 17 feet from boring SB-1.' All four samples were analyzed for VOCs by USEPA Method 8240. The analytical results, which are presented in Table 1, indicate that the soil samples collected from borings SB-1 through SB-4 did not contain detectable concentrations `' of VOCs. In November 1990, Augeas re-excavated the former Tank 2 area. The depth of the final excavation was reported to be approximately 19 feet. Soil samples for analysis of VOCs were not collected from the base or sidewalls of the excavation. The re-excavated area was reportedly backfilled with clean, imported material which was compacted (to 95 percent compaction) and brought to grade in 8- to 12-inch lifts. 6W ' Because the north end of the former tank pit had subsided approximately 2 feet, the starting elevation of boring SB-1 was approximately 2 feet below grade. Therefore, low the sample labeled SB-1.15 was collected at a depth of 17 feet. 6" CYPRESS Universal-Rundle Corporation Page 2 6W