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i <br /> J ,r <br /> ATTACHMENT A <br /> FIELD AND LABORATORY PROCEDURES <br /> Drilling and Well Installation Procedures <br /> The soil borings and groundwater monitoring wells were drilled using 8-inch hollow-stem <br /> I <br /> auger drilling equipment and Iogged by a Pacific Environmental Group, Inc geologist using <br /> the Umfied Soil Classification System and standard geologic techniques Soil samples for <br /> logging and chemical analysis were collected at a mimmum of 5-foot depth intervals using a <br /> Califorrua-modified split-spoon sampler The split spoon sampler was driven a maximum of <br /> 18 inches using a 140-pound hammer with a 30-inch drop Soil samples for chemical analysis <br /> were retained in brass liners, capped with Teflon squares and plastic end caps, and sealed in <br /> clean zip-lock bags The samples were placed on ice for transport to the laboratory <br /> accompanied by chain-of-custody documentation All down-hole drilling and sampling <br /> equipment was steam-cleaned following the completion of each soil boring Down-hole <br /> sampling equipment was washed in a tn-sodium phosphate solution between samples <br /> Four borings were converted to groundwater morntoring wells by installing 2-inch diameter, <br /> flush-threaded, Schedule 40 PVC casing with 0 020-inch factory-slotted screen Approxi- <br /> mately 20 feet of screen was be placed in the bottom of each boring An RMC 2 x 12 sand <br /> pack was placed in the annular space across the entire screened interval, and extends approxi- <br /> mately 2 foot above the top of the screen for each well A bentonite and Portland cement <br /> seal was placed from the sand pack to the ground surface After completion each soil boring <br /> was abandoned by placing Portland cement grout from the bottom of the boring, through a <br /> tremie pipe to the ground surface <br /> Following well completion, the vault box elevation and the elevation of the top of the PVC <br /> well casing of the monitoring wells was surveyed to the nearest 0 01 foot, relative to mean sea <br /> level, by a licensed surveyor The attached boring logs show well construction details <br /> Organic Vapor Procedures <br /> Soil samples collected at 5-foot depth intervals during drilling were analyzed in the field for <br /> ionizable organic compounds using the HNU Model PI-101 (or equivalent) photo-ionization <br /> 3201591A/PEPORT A- 1 May 6, 1996 <br /> 1 <br />