ARCHIVED REPORTS XR0000768 - Laserfiche WebLink

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driven sampling device To reduce the potential for cross-contamination between samples, the sampler will be cleaned between each sampling event Upon recovery, the sample container will be sealed at each end with TeflonT"" sheeting and plastic caps to minimize the potential of volatilization and cross-contamination prior to chemical analysis The soil sample will be labeled, placed in an ice chest cooled to 4° Celsius, and delivered to a state-certified analytical laboratory, along with the appropriate chain-of custody documentation Sample Identification and Chain-of Custody Sample identification and chain-of-custody procedures document sample possession from the time of collection to ultimate disposal Each sample container submitted for analysis has a label affixed to it to identify the lob number, sampler, date and time of the sample collection, and the sample number unique to that sample This information, in addition to a description of the sample, field measurements made, sampling methodology, names of onsite personnel, and any other pertinent field observations, are recorded on the borehole log or in the field records A chain-of-custody form is used to record possession of the sample from the time of collection to its arrival at the laboratory When samples are shipped, the person in custody of them relinquishes the samples by signing the chain-of custody form and noting the time Monitoring Well Installation Monitoring wells will be completed by installing one two-inch-diameter Schedule 40 polyvinyl chloride (PVC) casing The two-inch diameter monitoring wells will be installed using 8-inch diameter hollow stem augers Monitoring wells will be constructed using threaded, factory-perforated and blank Schedule 40 PVC The perforated interval consists of slotted casing, 0 02 inches wide by 1 5-inch long slots, with 42 slots per foot The screened interval will allow for seasonal fluctuation in water level and for monitoring floating product A threaded PVC cap is secured to the bottom of the casing The well casing is thoroughly washed and/or steam cleaned, or may be purchased as pre-cleaned, prior to completion A filter pack of graded sand will be placed in the annular space between the PVC casing and the borehole wall Sand will be added to the borehole through the hollow stem of the augers provide a uniform filter pack around the casing and to stabilize the borehole The sand pack will be placed to a maximum of 2 feet above the screens, followed by a minimum 1-foot seal consisting of bentonite pellets or chips Cement grout containing 5 percent bentonite will be placed above the bentonite seal to the grout surface A concrete traffic-rated vault box will be installed over the monitoring wells A water tight locking cap will be installed over the top of the well casing Monitoring well elevations will be surveyed by a state-certified land surveyor to the nearest 0 01 vertical feet relative to mean sea level (MSL) Horizontal coordinates of the wells will also be obtained at the same time Equipment Cleaning Sample bottles, caps, and septa used in sampling for volatile and semivolatde organics will be triple rinsed with high-purity deiornzed water After being rinsed, sample bottles will be dried overnight at a temperature of 200°C Sample caps and septa will be dried overnight at a temperature of 60°C Sample bottles, caps, and septa will be protected from solvent contact between drying and actual use at the sampling site Sampling containers will be used only once and discarded after analysis is complete