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Harding Lawson Associates U, LL To the south of the former dispenser location, the limit of excavation extended approximately 16 feet, with a width of between approximately 13 feet near the dispenser, and approximately 7 feet at its southern limit (Plate 3). The floor of the final Uexcavation was approximately 6.5 feet deep from the former dispenser location, to the south for approximately 6 feet. From approximately 6 to 16 feet south of the former dispenser location, the excavation floor was approximately 3.5 feet deep. Approximately; 40 cubic yards of soil was removed from the entire excavation. # L5.2 Excavation Sampling and Logging LI After the excavation was completed, the exposed soil of the excavation floor and t walls was monitored for the presence of organic vapors to assess the level of Ghydrocarbons remaining in the soil. This monitoring was conducted by having the backhoe remove soil from the floor and walls at regularly spaced intervals and from the j 1 different soil types exposed and monitoring'-the soils with the OVA.rSeven confirmation soil samples, designated as 91060601 through 91060607, were collected from the excavation floor (samples 91060601 and 91060602), and walls (samples 91060603 through 91060607) at locations where the highest concentration of petroleum hydrocarbons were t measured by the OVA or from locations with OVA readings that were representative of the entire excavation wall. The confirmation soil sampling locations are presented on Plate 3. The confirmation soil samples were collected by having the backhoe remove a bucket of soil from the sampling location. A few inches of soil was scraped from the surface of the soil in the bucket and a clean stainless steel tube was pushed into the material until it was completely full. Each sample tube was then removed, the ends were sealed with Teflon-lined plastic caps, taped, labeled, placed in a plastic ziplock i L 7'19461-H 10 of 20 L