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a S lEC ® R ATTACHMENT 3 FIELD AND LABORATORY PROCEDURES Exploratory Drilling The soil borings for well SVE-2 were drilled using 8-inch hollow-stem auger drilling equipment and for wells EW-3, EWA EW-5, EW-6, and EW-7 were drilled using 10-inch hollow-stem auger drilling equip- ment Borings were logged by SECOR field staff using the Unified Sod Classification System and stan- dard geologic techniques Soil samples for logging and laboratory analysis 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 selected for chemical analysis were retained in brass liners, capped with Teflon® squares and plastic end caps, and sealed in ZiplockTM-style bags The samples were placed on ice for transport to the laboratory accompanied by chain-of-custody documentation All down-hole drilling and sampling equipment was steam-cleaned prior to and following the completion of the sod borings Down-hole sampling equipment was washed in a trisodium phosphate or alconox solution between samples Organic Vapor Procedures Soil samples collected at 5-foot depth intervals during drilling were 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 involved measuring approximately 30 grams from an undisturbed soil sample, placing this subsample in a ZiplockTM-type bag or in a clean glass jar, and sealing the jar with aluminum foil secured under a ring-type threaded lid The container was warmed for approximately 20 minutes (in the sun), then Y the head-space within the container was tested for total organic vapor, measured in parts per million as benzene (ppm, volume/volume) The instrument was calibrated prior to drilling The results of the field- testing were noted on the boring logs (Attachment 4) FIDIPID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate petroleum hydrocarbon levels with the confidence of laboratory analyses i Groundwater Monitoring Well Installation and Development Each groundwater extraction well was completed within the sod boring by installing a 6-inch diameter, flush-threaded, schedule 40 PVC casing with approximately 20 feet of 0 020-inch wire wrapped screen An RMC 2/12 sand pack, or equivalent, was placed in the annular space across the entire screened W interval, extending approximately 1 foot above the top of the screen A 3-foot bentonite transition seal was placed atop the sand pack, followed by a cement seal at the ground surface The boring logs show well construction details (Attachment 4) Soil vapor extraction well SVE-2 was completed within the soil boring by installing a 2-inch diameter, flush-threaded, schedule 40 PVC casing with approximately 20 feet of o- 0 020-inch factory slotted screen Cascade Drilling, under the supervision of SECOR, developed the groundwater extraction wells on September 3 and 4, 2003 The development procedure for the welt consisted of pumping and balling water from the well until the purge water was visibly clear, the wells went dry, or until a maximum of ten casing volumes had been removed The well development sheets are included in Attachment 6