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r The site topography is relatively flat at an average elevation of 103 feet above sea level. There are no naturally occurring streams or rivers within 2000' of the site as shown on the topographie map for the site presented in Figure 2. 5.0 Tank Removal soil Analysis and Chronology Tank T-2, a 1.0,000 gallon diesel tank, situated within the Laura Scudder's Tracy plant (Figure 3) , was removed in 1987. At the time of the tank removal, a single soil sample was collected from native soils beneath the tank area. Analysis of the soil sample indicated the presence of Total Petroleum Hydrocarbon (TPH) concentrations of 8200 mg/Kg. Based on this TPH concentration, the tank removal contractor further investigated soils in the tank area. This investigation consisted of hand augering to the depth of 19' beneath each tank end area (Figure 4) and collecting two soil samples (19N and 19S) . The results of the analysis of these soil samples are presented in Table 1. Following the receipt of these analytical results, the tank removal contractor excavated the tank removal area to a depth of 201. Two soil samples were then collected from the bottom of the excavated area (1 south and 1 north) . Analysis of these samples did not indicate any residual hydrocarbon compounds. The area was then backfilled. Current attempts by Laura Scudders to obtain clean closure for the tank T-2 removal area as well as other tank removal areas at the site have resulted in the resurrection of concern regarding the soil conditions beneath this tank area. Tank T-1, a 1000 gallon gasoline storage tank, located as shown on Figure 3, was removed in May 1989. Analysis of confirmation soil samples from the tank bottom area indicated only the presence of total lead in concentrations up to 61.3 mg/Kg. An organic lead fraction analysis conducted on one of the samples indicated that no organic lead was present. However, the question still exists as to the extent of the soluble fraction of lead at the site. 6,0 Proposed Work Plan 6.1 Tank T-2 Based on the analysis of the initial soil boring samples (19N and Table able 1) which indicated a lack of significant petroleum hydrocarbon compounds Beneath the excavated area as well as the excavation confirmation soil samples (1 south and 1 north, Table 1) which confirmed this indication, it appears that the excavation of the tar'k area by the tank removal contractor was successful in the removal of the majority of the petroleum hydrocarbon compounds down - to 20' . However, due to the lack of data beneath the 20' depth, it is --- - -- -- -— -— - - uncertain if the compound presence initially detected (8200 mg/Kg TPH(D) ) had not migrated vertically below the 20' depth. - 4 -