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collected so far have shown EDB or lead above levels of concern, r� analysis for these compounds is not required Samples will be collected from the bottom of the excavation as well as select spots along the excavation walls The proposed sampling grids for Sites 1 and 2 are shown in Figure 5-2 For Site #1, one sample will be collected from the center bottom of the excavation, one sample will be collected at the bottom of each sidewall, and up to four additional samples may be collected from higher up along the excavation sidewalls For Site #2, samples will be collected along grid intersections of a 20 by 20 foot grid The grid net will extend across the bottom of the excavation to the excavation sidewalls Samples will be collected either by directly driving a pre-cleaned brass tube six inches deep into the soil, or by collecting a sample from the backhoe bucket For samples collected from the backhoe bucket, the backhoe will collect a full bucket from the appropriate sampling location A pre-cleaned brass tube will then be pushed into the mass of soil in the backhoe bucket until the tube is filled Tubes will be sealed by placing Teflon® film over the ends and securing it in place with plastic caps Each tube will be labeled with a unique sample number The tubes will then be placed in a Ziploc(&-type plastic bag, sealed, and placed on ice in a cooler until they are analyzed S An attempt will also be made to collect samples from underneath the buildings in areas where the affected sols appear to extend below the ' building The stiffness of soils ad)acent to and underneath the buildings will determine whether samples can be collected If the soils are sufficiently soft, soil samples will be collected from underneath the building by hand-augering up to 15 feet horizontally underneath the building from the edge of the excavation The depth of the samples collected from underneath the building will be limited by the depth of the excavation The maximum depth of the soil samples collected underneath the building will be one foot less than the depth of the excavation because use of the hand-auger will require a minimum one foot clearance In all directions The samples from underneath the buildings will also be analyzed for TPH and BTEX Because sampling will be occurring concurrent with the excavation, certain locations may be sampled multiple times Once the excavation is believed to be complete, the soil sampling locations will be compared ' to the proposed grid to ensure that the proper number of samples were collected from the required locations If necessary, confirmation sampling will be completed by sampling any grid or centerline locations that have not been sampled and shown to meet the cleanup ( criteria r 5-4