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