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PRIVILEGED & CONFIDENTIAL 16 Boring B5 was drilled to a depth of 80 feet bgs. Soil samples were collected continuously ' from five to 80 feet bgs. The sampler was driven by a 140-pound hammer that advanced the sampler approximately 18 inches. The blow counts for each six inches were recorded on the boring logs. Soil samples were collected using a two-inch split spoon sampler. Soil samples were collected in three six-inch long, 1.5-inch diameter brass tubes inside the sampler. The soil in the center-portion of the sample tube was used to describe the soil lithology. A Photovac Microtip Model No. HL-2020 photo ionization detector (PID) was used to measure volatile organic compounds (VOCs). Approximately 1/2 of the soil was removed, and placed in a sample tube capped at both ends with polyethylene caps. The sample in the sample tube was then agitated and set aside to allow organic vapors, if present, to accumulate in the void space (headspace) of the sample tube. The headspace was then evacuated with a PID equipped with a probe. The measurements were considered in the selection of soil samples for laboratory analyses. The PID readings were recorded on the boring log along with soil descriptions and soil classifications according to the United Soil Classifications System (USCS). Coordination 1 and supervision of drilling and soil sampling activities were performed by a State of California Registered Geologist. The boring log is included in Appendix B. ' Following retrieval of the sampler, the bottom six-inch Iona tube was removed from the sampler, and the ends were covered with Teflon tape and capped with polyethylene end caps. The sample tube was labeled with the sample number, collection date and project number, was placed in a cooler chilled to approximately 4° C (40° F), and retained for laboratory analyses. Soils beneath the site consisted primarily of clays, silts, sands and mixtures of these sediments. Field observations of soil samples collected from Boring B5 between 33 and 70 feet bgs revealed a grayish discoloration, and exhibited a very slight to strong gasoline- like odor. Groundwater Sampling Subsequent to the collection of the deepest soil sample, several of the auger flights were removed and groundwater was allowed to flow into the borehole. Groundwater was encountered in the boring at approximately 50 feet bgs. After waiting approximately 20 to 30 minutes to allow the sediments to settle, a groundwater sample was collected by lowering a new two-inch Teflon disposable bailer below the static water level, and raising the bailer slowly in order to minimize agitation of the water sample in the bailer. I Water was discharged from the bailer through a bottom discharge valve into the sample container, at a rate slow enough to minimize agitation of the liquid- The sample container was filled to the top (from the bottom up) and overfilled leaving no headspace. The samples were collected in laboratory-approved glass 40-milliliter vials. Following collection of the samples, the vials were labeled with the sample number, collection date and project number, placed into a cooler chilled to approximately 4° C (40° F), and retained for laboratory analyses. < j 5 198075-WFB,Swxklnn Ph.II and Quart.Groundwater