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ATTACHMENT D FIELD AND LABORATORY PROCEDURES Exploratory Drilling and Soil Sampling The soil borings will be drilled to depths of approximately 20 feet bgs. Borings will be drilled using 8-inch hollow-stem auger drilling equipment and logged by a SECOR geologist using the Unified Soil Classification System and standard geologic techniques, under the direction of a California Registered Geologist. Soil samples for logging will be collected at 5-foot depth intervals using a California-modified split-spoon sampler. The sampler will be driven a maximum of 18 inches using a 140-pound hammer with a 30-inch drop. Soil samples for chemical analysis will be retained in brass liners, capped with Teflon squares and plastic end caps, and sealed in clean zip-lock bags. The samples will be placed on ice for transport to the laboratory accompanied by chain-of-custody documentation. All down-hole drilling and sampling equipment will be steam-cleaned following the completion of each soil boring. Down-hole sampling equipment will be washed in a tri-sodium phosphate or alconox solution between samples. Groundwater Sampling Procedures Groundwater samples will be collected using "hydropunch" equipment. The samples will be placed on ice for transport to the laboratory accompanied by chain-of-custody docu- mentation. Organic Vapor Procedures Soil samples collected at 5-foot depth intervals during drilling will be analyzed in the field for ionizable organic compounds using a flame-ionization detector (FID) or a photo- ionization detector (PID) with a 10.2 eV lamp. The test procedure will involve measuring approximately 30 grams from an undisturbed soil sample, placing this subsample in a ziplock type bag or in a clean glass jar and sealing the jar with aluminum foil secured under a ring-type threaded lid. The container will be warmed for approximately 5 minutes (in the sun), then the head-space within the container will be tested for total organic vapor, measured in parts per million as benzene (ppm; volume/volume). The instrument will be calibrated prior to drilling using a 100-ppm isobutylene standard (in air) and a sensitivity factor of 55, which relates the photo-ionization potential of benzene to that of isobutylene at 100 ppm. The results of the field testing will be noted on the boring logs. PID and FID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon levels with the confidence of laboratory analyses. I:ARC0\5450\wo kplanAsite contamination wkpin.doc