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i ATTACHMENT 3 FIELD AND LABORATORY PROCEDURES i Exploratory Drilling Soil borings were drilled using air rotary/casing hammer drilling equipment Using the Unified Sod Classification System and standard geologic techniques, sod cuttings from the borings were logged by a SECOR geologist to a depth of 70 feet bgs in the boring for well MW-8 and to a depth of 50 feet bgs in the boring for well MW-10 Lithology encountered within the boring for well MW- 9, beyond 70 feet bgs in the boring for well MW-8, and beyond 50 feet bgs in the boring for well MW-10 were also evaluated from the collection of soil samples at 10-foot intervals to the total depth explored All down-hole drilling and sampling equipment was steam-cleaned prior to and following the completion of each soil boring Down-hole sampling equipment was washed in a trisodium phosphate or alconox solution between samples Groundwater Monitoring Well Installation A groundwater monitoring well was completed in each of the three soil borings by installing a 2-inch diameter, flush-threaded, Schedule 40 PVC casing with 0 020-inch factory-slotted screen Approximately 10 feet of screen was placed in each of the groundwater monitoring wells An RMC 2112 sand pack, or equivalent, was placed in the annular space across the entire screened interval, and extended approximately 2 to 3 feet above the top of the screen for each well A 3- foot bentonite transition seal was placed atop the sand pack, and a cement grout mixture extended from the bentonite transition seal to the ground surface Each well was secured by a locking expandable well cap, and fitted with a traffic-rated well box set in concrete Boring bgs in Attachment 4 show well construction details Rinsate/Purge Water and Soil Cuttings Soil cuttings, ansate water generated during steam cleaning of equipment, and water encountered during the installation of the wells was stored in a roll-off bin placed along the northern boundary of the site During the course of drilling activities, approximately 2,400 gallons of water were removed from the bin by FRC of Rialto, California using a vacuum truck, and transported to their facility for treatment/recycling Following waste profiling, the bin containing the soil cuttings was removed from the site by FRC on December 22, 2003, the soil cuttings were transported to their facility for treatment/recycling The groundwater monitoring wells were developed and sampled by SECOR on December 10, 2003 The development procedure for each well consisted surging the length of the well screen, and pumping and/or bailing water from the well until (1) the water was visibly clear, (2) monitoring parameters of temperature, conductivity, and pH stabilized to within 10 per cent and turbidity had stabilized to less than 100 ntus, (3) the well went dry, or (4) until a maximum of ten casing volumes had been removed Approximately 140 gallons of purge water were generated during the development of wells MW-8 through MW-10, and stored DOT-approved 55-gallon steel drums During well development activities, residual water was pumped from the roll-off bin containing the soil cuttings, and transferred into additional drums on-site for future transport to A total of 7 drums containing water generated during drilling and well development activities will be removed from the site by FRS, and transported to their facility for treatment/recycling . Non-hazardous waste manifests for the transport of the bin containing soil cuttings, and water generated during drilling and well development activities are included in Attachment 8