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dispenser during tank removal activities (these fluids were <br />retrieved with a small volume of soil, and placed in the tank <br />prior to its transport). <br />2.3 Tank Disposal <br />The tank and appurtenant piping were transported with a hazardous <br />waste manifest by a licensed hazardous waste transportation <br />company (H&H Ship Services) to their receiving facility in San <br />Francisco, California. The tank was subsequently steam -cleaned, <br />cut, and rendered harmless by H&H Ship Services and disposed of <br />as scrap metal at Levin Metals Corporation, in Richmond, <br />.. California. A copy of the manifest and the Certificate of <br />Disposal are included in Appendix A. <br />2.4 Sampling Procedures and Locations <br />Excavation bottom soil samples were collected from the native <br />soils 2 feet below the backfill/native soil interface with a <br />backhoe. The soil samples were taken from the backhoe bucket in <br />clean brass tubes, labeled, capped with aluminum foil and plastic <br />caps, and sealed with electrical tape. Samples were stored in a <br />chilled container and transported for analysis to NET Pacific in <br />Santa Rosa, California, a State -certified laboratory. Samples <br />were transported under strict chain -of -custody protocol. <br />Two soil samples were collected from native sediments beneath the <br />former bottom of the tank. Samples were collected from each end <br />of the excavation (sample TN -14' and TS -141). Four samples were <br />collected in native soils beneath the former product pipe <br />(PP1-31, PP2-2.51, PP3-2.5' and PP4-31), one for each joint <br />located along the 80 -foot section of pipe between the dispenser <br />island and tank excavation boundary. One sample, DI -2.51, was <br />collected from beneath the former dispenser island. Sampling <br />locations are shown on Figure 2. <br />2.5 Excavation Backfilling <br />The excavation was backfilled, compacted with tank backfill sands <br />and imported sand, and re -surfaced with aggregate -base material <br />and asphalt concrete to match existing grade. This work was <br />performed by Trumpp Brothers subsequent to the tank removal. <br />Compaction of the backfill materials in the tank excavation was <br />completed using backhoe -mounted roller equipment on approximately <br />2 -foot thick lifts from the bottom of the excavation to a depth <br />of about 3 feet; the remaining depth was compacted in 1 -foot <br />lifts with portable Whacker vibratory compaction equipment. In <br />the southern end of the excavation, where the tank had extended <br />beneath an above -ground loading dock by about 6 feet, a space of <br />approximately 2 feet beneath the dock could not be backfilled <br />with compacted sand; therefore, a controlled -density cement <br />-3- <br />