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Mr Ronald Rowe <br /> CAM B R I A August 26, 1999 <br /> Soil Boring <br /> We recommend drilling one soil boring at the site immediately adjacent to boring SB-3 in the <br /> suspected hydrocarbon source area. (Figure 1) The boring will be drilled to 80 fbg (the depth <br /> indicated by the SJCPHS as the historic low water table during station operations) and <br /> continuously logged to 80 fbg <br /> We will collect groundwater samples using a driven grab sampler in coarse-grained sediments <br /> identified by the CPT boring log Groundwater samples may also be collected from fine-grained <br /> sediments at different depth intervals to determine if vertical migration of hydrocarbons is <br /> occurring or if the hydrocarbons appear to originate from an off-site source This will also allow <br /> us to profile hydrocarbon concentrations in groundwater beneath the site and determine whether <br /> the existing wells are providing representative data <br /> A Cambria geologist will supervise the drilling and describe encountered soils using the Unified <br /> Soil Classification System and Munsell Soil Color Chart Selected soil samples will be properly <br /> sealed, labeled, and entered onto a chain-of-custody record for chemical and physical property <br /> analysis Samples will be selected for chemical analysis based on field screening with an <br /> organic vapor meter (OVM) Samples will be preserved in a cooler with ice for transport to a <br /> State of California certified laboratory Our standard field procedures are included in Attachment <br /> E <br /> Chemical Analysis <br /> Soil samples will be analyzed for TPHg, benzene, toluene, ethylbenzene and xylenes (BTEX), <br /> and MTBE Ground water samples will be analyzed for TPHg, BTEX and MTBE by EPA <br /> Method 8015/8020,and MTBE and other fuel oxygenates by EPA Method 8260A <br /> PIP <br /> Physical Property Analysis <br /> We will analyze one soil sample from major lithologic units encountered for permeability, <br /> porosity, density, and organic carbon content <br /> Ground Water Monitoring Wells <br /> If the analytic data indicates that additional wells are warranted, then we will recommend <br /> appropriate well locations and screened depths adjacent to existing wells that currently have <br /> . submerged screen intervals The well screens for the new wells will be based on the analytic <br /> 7 <br />