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S E C O R -.1 - ATTACHMENT B FIELD AND LABORATORY PROCEDURES Exploratory Drilling Soil borings will be drilled using 8-inch hollow-stem auger drilling equipment. The borings will be logged by SECOR field staff using the Unified Soil Classification System and standard geologic techniques. Soil samples were collected at 5-foot depth intervals using a California-modified split-spoon sampler. The sampler was driven a maximum of 18 inches using a 140-pound hammer with a 30-inch drop. All soil samples for chemical analysis will be retained in brass sleeves, capped with Teflon® squares and plastic end caps, and sealed in ZiplockT"-style 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 prior to and following the completion of the soil borings. Down-hole sampling equipment will be washed in a trisodium phosphate or alconox solution between samples. 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 PID with a 10.2 eV lamp. The test procedure involves measuring approximately 30 grams of an undisturbed soil sample and placing this subsample in a ZiplockTm-type bag. The container will be warmed for approximately 20 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 by volume). The instrument will be calibrated prior to drilling. The results of the field-testing will be noted on the boring logs. FID/PID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate petroleum hydrocarbon levels with the confidence of laboratory analyses. Groundwater Monitoring Well Installation and Development The groundwater monitor wells will be completed by installing a 2-inch diameter, flush-threaded, schedule 40 PVC casing with 0.020-inch factory-slotted screens. Approximately 5 to 20 feet of screen will be used to construct the monitor wells. A#3 sand pack, or equivalent, will be placed in the annular space across the entire screened interval, extending approximately 2-feet above the top of the screen. A 3-foot bentonite transition seal will be placed atop the sand pack, followed by a neat cement seal, extending from the top of the bentonite transition seal to the ground surface. The boring logs will show well construction details. The development procedure for each well consists of swabbing the screen interval and pumping or bailing approximately ten casing volumes of water from the wells. The well development sheets will be included in the assessment report.