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ti ATTACHMENT 1 FIELD AND LABORATORY PROCEDURES i Exploratory Drilling The soil borings for the OS and groundwater monitoring wells will be drilled using 8-inch hollow-stem auger drilling equipment. Each boring will be logged by a SECOR geologist using the Unified Soil Classification System and standard geologic techniques. Soil samples for logging and possible laboratory analysis 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. All soil samples selected for chemical analysis will be retained in brass liners, capped with Teflon® squares and plastic end caps, and sealed in ZiplockTM-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 will be collected at 5-foot depth intervals for analysis 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 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 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; volume/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. . I Ozone Sparge Well/Monitoring Well Installation and Development Each OS well will be completed within a soil boring by installing a 1.25-inch diameter, flush-threaded, Schedule 80 PVC casing equipped with a 3-foot long ozone sparging diffuser tip. Each groundwater monitoring well will be completed within a soil boring by installing a 2-inch diameter, flush-threaded, Schedule 40 PVC casing with approximately 20 feet-of 0.020-inch factory-slotted screen. An RMC 2/12 sand pack, or equivalent, will be placed in the annular space across the entire screened interval, extending at least 2 feet above the top of the screen. A 2-foot bentonite transition seal will be placed atop the sand pack, followed by a cement seal, extending from the top of the bentonite t ansittiion seal fo the ground surface. The boring logs will show well construction details. The groundwater monitoring wells will be 'developed by SECOR after completion. The development procedure for the well consists of pumping and/or bailing water from the well until the purge water is visibly clear, the wells go dry, or until a maximum of ten casing volumes have been removed. The well development sheets will be included in the future report submittal. Groundwater Sampling Procedures / The sampling procedure for each well will include measuring the water level, and checking for the presence of separate-phase hydrocarbons (SPH), using either an electronic indicator and a clear Teflon® a 11ConocoPhi1lips\Tosco Marketing\11193\Reports\Revised IRAP&WPAM . � r