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%W01 NOW 15 July 2004 AGE-NC Project No. 98-0540 Page 9 of 10 4.5.2. Well Evacuation Subsequent to measurement of depth to water and prior to sampling, the well will be purged using a submersible pump or a disposable bailer to ensure that the sample is representative of the formation,rather than water standing in the well casing.The well will be purged until: 1)a minimum of three casing-water volumes is removed from the well; and/or 2)the field-measured ground water parameters have stabilized. However, if a well is purged dry prior to evacuating three casing-water volumes, a ground water sample will be collected following 80 percent recovery of ground water within the well or within 8 hours of well evacuation. 4.5.3. Sample Withdrawal Water samples will be collected from the monitoring well using a disposable polyethylene bailer. These bailers are disposed of after one use and require no decontaminating,thereby minimizing cross contamination due to sampling devices. Samples will be drawn and collected in such a manner that agitation and exposure of the groundwater to the atmosphere is minimal. Sample containers will be filled using the appropriate disposable sampling attachment which allows controlled flow out of the bottom of the bailer by lifting up on the check valve. 4.5.4. Sample Handling Ground water samples will be collected into laboratory-supplied containers. Ground water samples for BTEX,TPH-g, and fuel oxygenates analyses will be collected into 40-m1 VOA vials containing 0.5 ml of hydrochloric acid as preservative. Samples for TPH-d analysis will be collected into I-liter amber glass containers without a preservative. Following collection,the samples will be placed on ice and kept in a cooler until delivered to the laboratory for analysis.Chain-of-custody protocols will be used to document sample custody transfer from the field to the analytical laboratory.A chain-of- custody form will accompany the samples. 4.6. EQUIPMENT DECONTAMINATION All sampling tools used for sample collection will be thoroughly rinsed with clean water after being washed with a solution of Alconox.All down-hole drilling and sampling equipment will be pressure washed prior to starting each boring. Advanced GeoE nvi ron mental,Inc.