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21 August 2003 <br />AGE -NC Project No 03-1055 <br />Page 10 of 10 <br />3 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 to ensure that the ground water sample is representative of the formation, rather <br />than water standing in the well casing The well will be purged until 1) a minimum of three casing <br />volumes is removed from the well, and/or 2) the field -measured ground water parameters pH, <br />temperature and electrical conductivity have stabilized However, if a well is purged dry prior to <br />evacuating three casing volumes, a ground water sample will be collected following 80 percent <br />recovery of ground water level within the well or within 8 -hours of well evacuation <br />Purge water, free -product, and decontamination water generated during the ground water sampling <br />activities will be contained in DOT -approved drums which will be appropriately labeled for storage <br />Drums containing purge water will be stored on -sitz: pending appropriate removal and disposal <br />3 4 3 Sample Withdrawal <br />• Water samples will be collected from the monitoring wells using 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 i ummal 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 />3 4 4 Sample Handling <br />Ground water samples will be collected into laboratory supplied containers Ground water samples <br />to be analyzed for TPH-g, BTEX and fuel additives will be collected into 40-m1 volatile organic <br />analysis (VOA) vials containing 0 5 -ml of hydrochloric acid as preservative Following collection, <br />the samples will be placed on ice and kept in a cooler until delivered to the laboratory for analysis <br />Chain -of -custody protocols will be used to document sample custody transfer from the field to the <br />analytical laboratory A chain -of -custody form will accompany the samples <br />35 EQUIPMENT DECONTAMINATION <br />Advanced GeoEnvironmental, Inc <br />