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Following tank removal, two native soil samples will be collected from the base of the <br />tank excavation at the native soil and backfill interface; one from each end of the tank. Two <br />additional native soil samples will be collected from the sidewalls opposite the tank ends at the <br />soil and backfill interface. In the event that ground water is present in the excavation, the four <br />soil samples will be collected from the sidewalls of the excavation pit at the soil and ground- <br />water interface. Two additional soil samples will be collected from the tank piping trench, which <br />will be approximately 27 feet in length. The locations selected will be based on visual <br />observations of the underlying soils and areas where piping connections are found. The purpose <br />of obtaining the soil samples below the tank and piping is to determine the presence of <br />contamination beneath the backfill area. 1� <br />If soil contamination is visible after tank and piping removal, additional contaminated soil <br />will be removed from the excavations and trench. Because the tank removal is not intended to be <br />a permanent site remediation, no more than 75 cubic yards of soil will be removed based on an <br />excavation extending three feet beyond tank dimensions. At the extent of the additional soil <br />excavations, a total of two additional soil samples will be collected. <br />Analytical results of soil samples collected from the excavation pit will provide a <br />quantitative estimate of contaminants present in the soils. Sample analysis data will also provide <br />information needed to assess the effectiveness of the soil removal action and to determine if <br />additional source control measures are warranted. <br />Ito <br />To characterize the soil excavated during tank removal and during any additional 1 ��►.b <br />excavation, four soil samples will be collected from the excavated soil pile to meet state and San <br />Joaquin County regulations that require one sample be collected for every 20 cubic yards of <br />excavated soil. Soil samples from four separate locations in the pile will be collected and <br />submitted for analyses. These samples will be used to determine the level of contamination in the <br />excavated soils and, therefore, the proper method of soil disposal. <br />2.2 GROUND -WATER SAMPLES <br />One ground -water sample will be collected from within the excavation pit if ground <br />water is encountered during excavation. The objective of ground -water sampling is to determine <br />if possible releases from the tank have impacted ground water in the immediate vicinity of the <br />tank. One duplicate ground -water sample will also be collected. <br />VA <br />