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13',V6BI& CHANG ASSOCIATES PROCEDURES OF TEST BORING DRILLING, WELL INSTALLATION.- SOIL NSTALLATION;SOIL AND GROUNDWATER SAMPLING AND SAMPLE HANDLING Sampling Techniques Techniques employed for soil and groundwater sampling are essentially the same as described in the LUFT manual. Test borings are generally drilled with either a CME-45 or a CME-55 truck-mounted drill rig equipped with 3.75-inch I.D. continuous-flight hollow-stem augers. All test borings are logged by our field engineer, who also obtains representative soil samples for laboratory testing. Soil samples are taken at 5 foot intervals or less as instructed by the field engineer when field conditions warrant it. Soil samples are obtained by driving either a 2.0-inch Modified California Sampler or a 2.5-inch Modified Porter Sampler containing thin brass liners into the bottom of test borings. The procedures used in obtaining these samples are identical with the Standard Split Spoon Sampler (ASTM D-1786-84). When the sampler is withdrawn from the borings, the brass liners containing the samples are removed, field examined, labeled, and sealed for later laboratory testing. z After field examination, soil samples for hydrocarbon concentration testing are sealed with aluminum foil, capped with plastic end-caps, and wrapped in duct-tape. To further preserve the samples, the samples are then placed in a refrigerated ice-chest for transportation and storage. All soil samples are also tested in the field with a Gastech combustible gas detector for gas and vapor. Based on the field analysis, the on-site soils are preliminarily evaluated in the field as to the extent and amount of contamination. Groundwater samples are taken after the well has been fully developed and stabilized. Water samples are collected by using an individually packed disposable bailer, which is properly disposed of after each sampling. The groundwater sample collected by the bailer is transferred into either 1-liter amber glass bottles for Total Petroleum Hydrocarbon analysis (modified EPA 8015) or 40-milliliter VOA vials for Volatile Organics analysis (EPA 602) after the bailer is recovered from the monitoring well. Each of the groundwater sample bottles is sealed with a teflon-lined cap with no head space present in the sample container and labeled. The water samples are then placed in a refrigerated ice-chest for transportation and storage. 1 of 3