Laserfiche WebLink
' 25 Fe <br /> • bruary 2005 <br /> AGE-NC Project No. 98-0500 <br /> Page 7 of 6 <br /> ' using an electric water level indicator.Water level data will be recorded to the nearest 0.01-foot from <br /> a reference point marked on the top of each Teflon well casing. Before and after each use, the <br /> measurement device will be washed with a solution of Alconox and rinsed with clean water. <br /> 3.5.2. Well Evacuation <br /> Subsequent to measurement of depth to water and prior to sampling, each well will be purged by <br /> ' inserting a3/8-inch outer diameter polyethylene hose equipped with a ball-valve water tip(lift bailer) <br /> through the selected well chamber into the specific water-charged screened interval and oscillating <br /> the tube vertically to lift the water. The well will be purged until: 1) a minimum of three casing- <br /> water volumes is removed from the well;and/or 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 /> 3.5.3. Sample Withdrawal <br /> Water samples will be collected from the monitoring well screen using the same lift bailer used for <br /> purging.These bailers consist of 3/8-inch tube and base check-valve and are disposed of after one use <br /> and require no decontaminating,thereby minimizing cross contamination due to sampling devices. <br /> Care will be taken to ensure that visible air bubbles are not present in the vials after filling and <br /> capping. <br /> 3.5.4. Sample Handling <br /> Ground water samples will be collected into laboratory-supplied containers. Ground water samples <br /> will be collected into 40-milliliter (ml) volatile organic analysis (VOA) vials containing 0.5 ml of <br /> hydrochloric acid as preservative. Following collection the samples will be appropriately labeled, <br /> ' placed on ice and kept in a cooler until delivered to the laboratory for analysis. Chain of custody <br /> protocols will be used to document sample custody transfer from the field to the analytical <br /> laboratory. A chain of custody form will accompany the samples. <br /> • <br /> Advanced GeoEnvironmental,Inc. <br />