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V STANDARD FIELD INVESTIGATION AND SAMPLING PROCEDURES V B.1 SOIL SAMPLING PROCEDURES B.1.1 Grab Soil Samples The location of any soil grab sampling locations will be measured from prominent landmarks and marked on site maps. The soil samples will be collected using a clean metal trowel and new glass jars with teflon-lined lids provided by the laboratory. The soil will packed into the jar such that little or no headspace will be present in the jar. After collecting each soil sample, the jars will be assigned a unique sample number, labeled, and placed in a cooler with ice or ice substitute until delivery to the laboratory. ` B.1.2 Soil Borings ` Borings will be drilled with 6- to 10-inch-outside diameter, hollow-stem, continuous-flight augers. Soil sampling locations will be measured from prominent landmarks and marked on site maps. The soil samples will be collected using a modified California sampler, containing four ` stainless steel, brass, or equivalent tubes, each 2 inches in diameter and 4 inches in length. The sampler will be driven to the sampling depth by dropping a 140-pound hammer approximately 30 inches. Samples will generally be collected at 5 feet below ground surface, or 5 feet below former UST elevation, and at 5-foot intervals or significant changes in soil lithology, thereafter. Immediately after the sampler is retrieved from the auger, it will be placed on a portable field �- stand near the boring, and the tubes will be extruded. The ends of one of the tubes will be covered with teflon sheeting and capped with new polyvinyl chloride (PVC) end caps. Sample labels will be used to identify the soil-filled tubes. Each sample will be assigned a unique sample number. The samples will be placed in a sealable plastic bag. The sealed tubes will then be placed in a portable cooler and cooled with ice until delivered to the laboratory. The field stand will be swept free of soil between collection of samples. At each sampling interval, the soil in one of the remaining tubes will be extruded and placed into a sealable plastic bag. The bag will be closed and allowed to equilibrate for approximately 10 minutes. The organic vapor levels in the headspace will be measured using an Organic Vapor Analyzer (OVA), HNU, or equivalent. A headspace reading of 5 ppm for 10 seconds will indicate a positive hit. The soil sample will be visually examined and the results of the visual observations will be i recorded on the boring log. Information to be recorded on the boring log will include the `' B-1