Laserfiche WebLink
w <br /> APPENDIX A <br /> DRILLING AND SOIL SAMPLING PROCEDURES <br /> All drilling activities were performed by West Hazmat <br /> Drilling Corporation of Rancho Cordova, California using a <br /> truck-mounted CME 55 drilling rig. Soil borings were drilled <br /> using 4-inch-diameter, continuous-flight hollow-stem augers . <br /> To avoid cross-contamination, the augers were steam cleaned <br /> prior to drilling each boring. <br /> Soil samples were obtained for soil description, field <br /> hydrocarbon vapor testing, and laboratory analysis . Samples <br /> were collected at 5-foot intervals from the borings drilled <br /> for this preliminary site assessment. <br /> Soil samples collected at 5-foot intervals were retrieved <br /> ahead of the lead auger using an 18-inch-long by <br /> 2-inch-diameter split spoon sampler lined with <br /> 1 . 5-inch-diameter stainless steel sample tube inserts . The <br /> sampler and sample tubes were washed with an Alconox solution <br /> and rinsed before each sampling event. The sampler was <br /> driven by a 30-inch free fall of a 140-pound hammer. Blow <br /> counts were recorded for three successive 6-inch intervals . <br /> Upon retrieval from the sampler, the sample sleeve was <br /> removed and securely sealed with aluminum sheeting and <br /> polyurethane caps . The sample was labeled with sample <br /> identification, sample depth, engineer' s initials, and date <br /> of collection. The soil sample was kept on ice prior to and <br /> during transport to a California-certified laboratory. <br /> The remaining soil recovered was described in accordance with <br /> the Unified Soil Classification System. For each soil type, <br /> field estimates of density/consistency, moisture, color, <br /> grading, and soil type were recorded on the boring logs . <br />