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\+r •. Sampling Methods Truck-Mounted Hollow-Stem Augering A truck-mounted hollow-stem auger was used to collect impact-soil samples where deep sampling is required, or in terrain where soils are cemented or particularly indurated. Hollow- stem auger sections vary in diameter and length, but soil samples are commonly taken with 8- inch (O.D.) augers, joined in 5-foot sections. Hollow-stem-auger samples are collected in cylindrical, thin-walled brass, stainless steel, or polyvinyl-chloride (PVC) tubes (sleeves) that range in length from 3.0 to 6.0 inches. Soil sampling tubes, in accordance with ASTM standards, are either 2.0 or 2.5 inches in outside diameter(O.D.). During the sampling process, three or four sampling tubes, plus a spacer tube, are placed in a "split-spoon" barrel sampler of the appropriate diameter. Sampling barrels are generally 18 inches long. Where possible, a split-spoon sampling barrel is driven its*entire length with a 140-pound, sliding, drop hammer. The sampling barrel is removed from the hollow-stem auger which remains in the open boring. The steel sample barrel is then dismantled, and all the sample tubes (containing largely undisturbed soil) are removed. After removal from the split-spoon barrel, samples are trimmed, sealed with Teflon patches, and capped with tight-fitting plastic caps. Soil samples may also be extruded from the tubes and subsequently placed in appropriate sample containers (e.g., glass jars). Impact Sampling A common hand-auger is frequently used in combination with impact sampling equipment to collect soil samples where shallow soil samples are needed. Impact samples are collected in cylindrical,6.0-inch long,2.0 inch-diameter(O.D.),thin-walled brass,stainless steel,or polyvinyl- chloride (PVC) tubes. During the sampling process, a single sampling tube is placed in a stainless-steel sampling barrel. — The sampling barrel is driven its entire length by hand, with a sliding drop hammer. The sampler is then removed from the open boring and the 6-inch sample tube (containing largely undisturbed soil) is removed. After removal from the sampling barrel, the sample is trimmed, sealed with a Teflon patch, and capped with tight-fitting plastic caps. The soil may be extruded from the tube and placed in appropriate sample containers (e.g., glass jars). Sierra-Pacific Groundwater Consultants, Inc. A-1