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CAMBRIA <br /> After a soil sample has been collected, soil from the remaining tubing is placed inside a sealed plastic bag <br /> and set aside to allow hydrocarbons to volatilize from the soil. After ten to fifteen minutes, a portable <br /> GasTecho or photoionization detector measures volatile hydrocarbon vapor concentrations in the bag's <br /> headspace,extracting the vapor through a slit in the plastic bag. The measurements are used along with the <br /> field observations, odors, stratigraphy and ground water depth to select soil samples for analysis. <br /> Grab Ground Water Sampling <br /> Ground water samples are collected from the open borehole using bailers, advancing disposable Tygon® <br /> tubing into the borehole and extracting ground water using a diaphragm pump,or using a hydro-punch style <br /> sampler with a bailer or tubing. The ground water samples are decanted into the appropriate containers <br /> supplied by the analytic laboratory. Samples are labeled,placed in protective foam sleeves,stored on crushed <br /> ice at or below 4°C, and transported under chain-of-custody to the laboratory. <br /> Duplicates and Blanks <br /> Blind duplicate water samples are usually collected only for monitoring well sampling programs,at a rate <br /> of one blind sample for every 10 wells sampled. Laboratory-supplied trip blanks;accompany samples <br /> collected for all sampling programs to check for cross-contamination caused by sample handling and <br /> transport. These trip blanks are analyzed ifthe internal laboratory quality assurance/quality control(QA/QC) <br /> blanks contain the suspected field contaminants. An equipment blank may also be analyzed ifnon-dedicated <br /> sampling equipment is used. <br /> Grouting <br /> If the borings are not completed as wells, the borings are filled to the ground surface with cement grout <br /> poured or pumped through a tremie pipe. <br /> F:\TEMPLATE\SOPs\GEOPROBE.WPD <br />