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Section 4 • • Field Procedures 5.1.2. Mobilization and Set-Up The DPT rig will be inspected to make sure the equipment is properly maintained, adequately decontaminated, and capable of achieving the objectives for drilling, sample collection, and abandonment of the boring. All field health and safety monitoring equipment will be calibrated according to the instrument manufacturer's specifications and/or project work plans. Once the DPT rig is sited at the sampling location, the driller will be directed to make sure the location is reasonably free of underground utilities by hand auguring to a depth of two feet bgs at each location. 5.1.3. Drilling The DPT and sample collection will be commenced by advancing the conductor casing and associated sample barrel (with liner) for the first three-foot increment. Each sample barrel will be retrieved as quickly and smoothly as possible. The borehole will be advanced in three-foot increments. The acetate liner containing the soil sample will be removed from the sample barrel and soil samples collected at 2 feet bgs, 6 feet bgs and 10 feet bgs. 5.1.4. Soil Sample Collection Composite subsurface soil samples will be collected using DPT sampling equipment. Soil samples will be analyzed for the COCs listed in Section 3. For the horizontal composite samples, soil samples will be collected from 0 to 4 feet bgs, 4 to 8 feet bgs, and 8 to 12 feet bgs at four locations (a, b, c and d) within each numbered grid and composited with the same interval of soil sample collected from each of the lettered locations. See Figure 2. At the locations designated for vertical composite samples, samples will be collected from evenly spaced locations throughout the boring depending on the depth of the boring and sent to the laboratory for compositing and analyses. Discrete soil sampling';will also be collected as dictated by T&R. Soil samples will be collected by cutting a six-inch section of the acetate sleeve and capping the ends with a Teflon^' film over each end of the liner, then sealing each end with plastic end caps. Samples will be submitted to Test America Inc. (Test America) laboratory in Pleasanton CA. Compositing of the samples will be conducted by the laboratory. Each soil sample will be labeled for identification. Each label will contain,at a minimum,the following information: ■ Project number ■ Boring identification ■ Sample number ■ Bottom depth of sleeve \\con.fsOtproje s\2008_Projects2M78 City of Stockton Soil Excavation\B.Originals\Samidling and Analysis Plan\Slocklon_SAP_Daft_062408_bh.doc 11 5-2 ERRG