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t - conductivity of the water stabilized, as measured by portable meters calibrated to a standard buffer and conductivity standard. The water level was allowed to recover to at least 80 t percent of the initial water level. A sample of the formation water then was collected from the surface of the water in each of the wells with the Teflon bailer and slowly transferred to laboratory-cleaned sample containers. The recovered fluids from sampling in each well were directed into type 17-E, steel, 55-gallon liquid waste drums approved for this use by the Department of Transportation Vapor-Extraction Construction The wells are constructed using clean 4-inch-inner-diameter, thread pointed, Schedule 40 polyvinyl chloride (PVC) casing. No chemicals, glues, or solvents are used in construction of the wells. The screened portion of the vapor-extraction well consists of a 5- and 10-foot sections of factory-perforated casing with slots. Unperforated casing is set from the top of the screen to several inches below surface grade. The annular space of each well is packed with pea gravel from the bottom of the screen portion to approximately 1 foot above the top of the screen A plug of bentonite pellets t (approximately 2 feet thick) was placed above the sand to prevent cement from entering the sand pack. The remaining annulus is backfilled to the ground surface with a mixture of water, cement, and bentonite. The construction details of the individual wells are shown on the Logs of Bonngs The wellheads are secured in cast-aluminum utility boxes with PVC aprons The boxes have watertight seals and are set in concrete approximately flush with the surrounding ground surface to reduce surface-water infiltration A special wrench is required to open the box This design discourages vandalism and reduces the possibility of accidental disturbance to the well. Each wellhead is also fitted with a locking well cage to further protect against unauthorized disturbance of the well Sampling of Drill CUttings Drill cuttings were sampled by scraping 6 to 12 inches of soil off the stockpile surface A sample was then collected by driving a hand-operated percussion sampler, equipped with a clean brass sleeve, into the stockpiled soil. Four soil samples were collected from the drill cuttings and composited into one sample for laboratory analyses The soil samples selected for possible laboratory analysis were removed from the sampler and quickly sealed in their brass sleeves with aluminum foil, plastic caps, and aluminized duct tape. The respective sample containers were labeled in the field with the job number, sample location and depth, and date, and promptly placed in iced storage for transport to the laboratory Chain of Custody Records were initiated in the field by the geologist or technician and accompanied the samples to a laboratory certified by the State of California to perform the analyses requested osz&car sioos,a 3 t