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%we .,i FUGRO WEST, INC. STANDARD OPERATING PROCEDURES RE: SOIL BORING SAMPLING SOP-1 During drilling with a hollow-stem auger or air-rotary rig, soil samples are typically collected in thin-walled brass or stainless steel tubes that are 6 inches long by 2 inches outside diameter. Three of the tubes are set, typically, in an 18-inch-long split-barrel sampler. The sampler is usually lowered into the open borehole attached either to the end of drilling pipe or on a wire-line hammer device. When possible, the split-barrel sampler is driven its entire length, either hydraulically or by repeatedly pounding a 140-pound hammer using a 30-inch drop. The number of drops (blows) used to drive the sampler is recorded on the boring log. The sampler is extracted from the borehole and the tubes containing the soil samples are removed. Upon removal from the sampler, the ends of the lowermost tube are typically covered with aluminum foil or "Teflon" sheets and plastic caps. The sample may be extruded from the tube and sealed within another appropriate cleaned sample container (e.g., glass jar). The sealed sample is labeled and refrigerated for delivery, under strict chain-of-custody documentation, to the analytical laboratory. These procedures minimize the potential for cross-contamination and volatilization of volatile organic compounds (VOC) prior to chemical analysis. Material from one of the other tubes is analyzed in the field, when required, using either a portable photoionization detector (PID) or equivalent analytical instrument. The purpose of this field analysis is to qualitatively determine the presence or absence of hydrocarbons. The soil sample is enclosed in a container (eg., plastic bag) to allow for some volatilization of VOC. The PID is then used to measure the concentrations of hydrocarbons within the container headspace. The data is recorded on the boring logs at the depth corresponding to the sampling point. Any remaining soil collected from the sampler at that interval is described geologically using the USCS or other appropriate classification system) on a boring log. All drilling and sampling equipment are either steam-cleaned or washed prior to use at each site and between boreholes to minimize the potential for cross-contamination. Sampling equipment is also cleaned between samples. Fugm West Inc. SOP-110x.",1994