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��U VE9 I !020 2.2.3 Soil Sample Collection During drilling activities, soil cores were retrieved from each borehole for soil logging purposes using a 4-foot-long by 2-inch-diameter core barrel sampler. The core barrels contained a plastic liner that retained a relatively undisturbed soil core from which discrete soil samples were collected. Discrete soil samples were selected,typically at four-foot intervals but also at some intermediate depths to the total depth drilled in each boring during the field screening process. Collected discrete soil samples were sealed in the plastic liners with Teflon tape and plastic end caps, labeled with identifying information, and stored in a pre-chilled ice-chest. Each soil sample was recorded on a chain-of-custody(COC)document for transportation to the laboratory and held for possible chemical analysis. Bureau Veritas collected soil samples for potential physical analysis(air permeability, porosity, volumetric air and water, moisture content, intrinsic permeability,grain density, dry bulk density, total organic carbon and soil classification)should a human health risk assessment be requested. Soil cores were field screened for indications of possible contamination and for the presence of volatile and ionizable compounds using a photoionization detector(PID)at each sample depth. The PID reading records total ionizable compounds in parts per million(ppm), but cannot identify or quantify specific compounds. The soil cores were examined for soil classification using the Unified Soil Classification System as a guideline. The soil lithology descriptions and the field screening results were recorded on soil boring logs that are presented in Appendix C. Field screening of soil cores,visual observations, PID readings, and the types of RECs being investigated, resulted in identifying some stained soils with slight to distinct petroleum hydrocarbon odors in borings BV-2, BV-3 and BV-4 at and below the groundwater table. PID readings were typically recorded at four-foot or less intervals during drilling. Drilling and sampling equipment were steam cleaned and/or washed in a solution of non- phosphate detergent, double rinsed with tap water after each use, and allowed to air dry. The soil cuttings generated during this LSI were contained and sealed in one drum and were left on the subject property pending a review of the analytical data for selection of the proper method for disposal. 2.2.4 Grab-Groundwater Sample Collection Upon completion of soil sampling activities, Bureau Veritas collected grab-groundwater samples from BV-1 through BV-5. To facilitate the collection of water samples, a temporary well point was inserted into each open borehole using 1-inch diameter PVC casing with the lower 5-foot section consisting of screened casing with 0.10-inch cut slots. The depth to groundwater was measured and recorded on the soil boring log sheets(Appendix C). Grab-groundwater samples were collected using inertial pumps using inert tubing with a check- valve. Grab-groundwater samples were placed into approved sample containers, labeled, and stored in a pre-chilled ice-chest. The collected grab-groundwater samples were recorded on a COC document for transportation to the analytical laboratory for chemical analysis. The temporary well casings installed in borings BV-1 through BV-5 were removed at the completion of groundwater sampling. Borings BV-1 through BV-3 were then sealed to the surface with neat cement grout from the bottom of the boring to the surface, as no additional sampling was conducted. A concrete surface plug was placed in the upper six inches of the borehole and leveled to grade. The lower portion of boreholes BV-4 and BV-5 were filled with dry bentonite pellets up to a depth of approximately 15 feet bgs. The pellets were naturally hydrated by the water in the lower portion of the boring and by sidewall moisture in preparation for soil vapor sampling as described in the next section. 4 Project Number 99008-008321.03