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05 September 2002 <br /> AGE-NC Project No. 01-0887 <br /> Page 8 of 9 <br /> 4.4.1. Static Water Level Measurements <br /> Prior to purging and sampling during quarterly groundwater monitoring events,static water level will <br /> be measured using an electric water level indicator. Water level data will be recorded to the nearest <br /> 0.01-foot from a reference point marked on the top of the PVC well casing. Before and after each <br /> use, the measurement device will be rinsed with water. <br /> 4.4.2. Well Evacuation <br /> Following depth to water measurements and prior to sampling, the well will be purged using a <br /> disposable bailer to ensure that the sample collected will be representative of the aquifer rather than <br /> water standing in the well casing. The well will be purged until: 1) a minimum of three casing-water <br /> volumes is removed from the well; and 2) the field-measured ground water parameters have <br /> stabilized. However, if the well is purged dry prior to evacuating three casing-water volumes, a <br /> ground water sample will be collected following 80 percent recovery of ground water within the well <br /> or within 8 hours of well evacuation. <br /> 4.4.3. Sample Withdrawal <br /> Water samples will be collected from the monitoring wells using a disposable polyethylene bailer. <br /> These bailers are disposed of after one use and require no decontaminating, therefore minimizing <br /> cross contamination due to sampling devices. Samples will be drawn and collected in such a manner <br /> that agitation and exposure of the groundwater to the atmosphere is minimal. Sample containers will <br /> be filled using the appropriate disposable sampling attachment which allows controlled flow out of <br /> the bottom of the bailer by lifting 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 BTEX, TPH-g, fuel oxygenating compounds, and fuel additive analyses will be collected into <br /> 40-m1 VOA vials containing 0.5 ml of hydrochloric acid as preservative. Following collection the <br /> samples will be appropriately labeled and placed on ice and kept in a cooler until delivered to the <br /> laboratory for analysis. Chain-of-custody protocols will be used to document sample custody transfer <br /> from the field to the analytical laboratory. A chain-of-custody form will accompany the samples. <br /> Advanced GeoEnvironmentab Inc. <br />