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3.0 TANK REMOVAL An excavator provided by Bob Evans Trucking was used to expose the tanks and remove the associated piping(Figure 2). Upgradient personnel arrived at the site at approximately 1:15 p.m., and witnessed H & A personnel cleaning and monitoring the UST's with an LEL meter. Tank#3, a 5,000-gallon unleaded gasoline tank, was certified safe for removal by the Stockton Fire Department at 1:50 p.m., and the tank was removed from the excavation at 2:00 p. m. The tankwas heavily encrusted with rust and partly cemented soil, which were removed with difficulty. No holes were noted in the tank, but an area approximately 2' x 3'near the north end of the tank was coated with a black, greasy, petroleum liquid. Tanks#I and#2, both 6,000-gallon unleaded tanks, were subsequently removed and cleaned. Blue-gray, petroleum-stained soil coated both tanks, particularly on the east side of tank #2. Both tanks were moderately rusted but no holes were observed in either tank. Tank#4, a 250-gallon waste-oil tank, was removed with a backhoe supplied by Bob Evans Trucking at 2:30 p.m. The tank was rusted, but there was no evidence of petroleum leakage and neither the tank nor surrounding soil were visibly discolored. 4.0 TANK EXCAVATION AND SOIL SAMPLING In general, the excavated soil was loose, light reddish-brown in color, and ranged in grain size from medium-grained sand to silt. However, the excavator reportedly encountered a "hardpan" layer in the main excavation while exposing the tanks. At completion, the gasoline tank excavation measured approximately 40 feet x 40 feet by 12 feet. The waste-oil excavation measured roughly 6 feet x S feet x 5 feet. Highly discolored soil was evident in the center of the large excavation, and strong gasoline odors were noted. Under the direction of Mr. Eric Trevena of EHD, the excavator operator deepened the large excavation to a depth of 15 feet, and a registered geologist from Upgradient collected six soil samples from the excavator bucket at that depth (Figure 2). The small excavation was deepened to S feet and one sample was collected from the backhoe bucket at that depth. Eight other samples were collected from the excavated soil, which had been segregated into three stockpiles. All samples were collected by driving a slide hammer, loaded with a brass sample sleeve, 6 inches into the soil. After removal from the sampler, the sleeves were covered with teflon sheets, capped, sealed with duct tape, labeled, and placed in a cooled ice chest. The samples were subsequently transmitted under chain of custody to McCampbell Analytical Laboratories in Pacheco, California. The chain of custody form and laboratory report are included in Appendix A.