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. 23 June 2000 <br /> AGE-NC Project No 98-0511 <br /> Page 7 of 8 <br /> 4 4 GROUND WATER SAMPLING PROCEDURES <br /> Ground water sample collection will be performed In accordance with pertinent applicable sampling <br /> protocols, details of which are presented below <br /> 4 4 1 Static Water Level Measurements <br /> Before sampling and during ground water monitoring, static water level will be measured using an <br /> electric water level indicator Water level data will be recorded to the nearest 0 01 foot from the <br /> surveyed reference point marked of the top of the PVC well casing Before and after each use, the <br /> measurement device will be washed and rinsed with water <br /> 4 4 2 Well Evacuation <br /> Subsequent to measurement of depth to water and prior to sampling, the well will be purged using <br /> a submersible pump or a disposable bailer to ensure that the sample is representative of the <br /> formation,rather than water standing in the well casing The well will be purged until 1)a minimum <br /> of three casing volumes is removed from the well, and/or 2) the field-measured ground water <br /> parameters have stabilized However, if a well is purged dry prior to evacuating three casing <br /> volumes, a ground water sample will be collected following 80 percent recovery of ground water <br /> within the well or within 8-hours of well evacuation <br /> 4 4 3 Sample Withdrawal <br /> Water samples will be collected from the monitoring well using a disposable polyethylene bailer <br /> These bailers are disposed of after one use and require no decontaminating,thereby minimizing cross <br /> contamination due to sampling devices Samples will be drawn and collected in such a manner that <br /> agitation and exposure of the ground water to the atmosphere is minimal Sample containers will be <br /> filled using the appropriate disposable sampling attachment which allows controlled flow out of the <br /> bottom of the bailer by lifting up on the check valve <br /> 4 4 4 Sample Handling <br /> Ground water samples will be collected into laboratory-supplied containers Ground water samples <br /> for TPH-g, BTEX and fuel oxygenates analyses will be collected into 40-m1 VOA vials containing <br /> 0 5 ml hydrochloric acid as preservative Following collection the samples will be placed on ice and <br /> Advanced GeoEnviron mental,Inc <br />