ARCHIVED REPORTS XR0001321 - Laserfiche WebLink

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The respective sample containers were labeled in the field with the job number, sample location, depth if applicable, 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 and accompanied the samples to a laboratory certified by the State of California to perform the ' analyses requested Vapor Extraction Well Construction The vapor extraction wells were constructed in the boring with thread-pointed, ' 4-inch-inner-diameter, Schedule 40 polyvinyl chloride (PVC) casing No chemical cements, glues, or solvents were used in well construction The screened portion of the ' wells consisted of 15 feet of factory perforated casing with 0 010-inch-wide slots The annular spaces in the wells were packed with peagravel to approximately 1 to 2 feet above the slotted interval A 3-foot-thick bentonite plug was added above the sand pack to prevent the cement from entering the well pack The remaining annulus was backfilled to grade with a bentonite cement slurry ' The wells were protected with a traffic-rated, cast-aluminum utility box equipped with a PVC skirt The box has a watertight seal to protect against surface water infiltration and must be opened with a special wrench The design of this box discourages vandalism and reduces the possibility of accidental disturbance of the well ' Groundwater Sampling The static water level in each well was measured to the nearest 0 01 foot with a Solutst electric water-level sounder cleaned with a laboratory grade, non-phosphatic detergent and deionized water before use in each well. A clean bailer was used to obtain a sample from the surface of the water in the well for subjective analysis of hydrocarbons The ' sample was retrieved and visually examined for floating product, sheen, color, and clarity Approximately three casing volumes of groundwater were purged from the wells using a stainless-steel electrical submersible pump The pump, cables, and hoses were cleaned with a laboratory grade, non-phosphatic detergent and water before use in each well The wells were purged until withdrawal was of sufficient duration to result in stabilized pH, ' temperature, and electrical conductivity of the water, as measured by portable meters calibrated to a standard buffer and conductivity standard The wells recovered to more than 90 percent of the static water level within 5 minutes of turning off the pump The ' groundwater purged from the wells was temporarily stored in 17-E, steel, 55-gallon liquid waste drums approved for this use by the Department of Transportation ' Hydrochloric acid (or other appropriate chemical) was added to the sample vials as a preservative A sample of the formation water then was collected from the surface of the water in each of the wells with a disposable clean Teflon bailer and slowly transferred to laboratory cleaned sample containers ' SAON 1PJ0108051080514W 313L-95Vas 3 A-2 Rev 0,8/2195