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3.3.2 Development and Sampling of Monitoring Wells <br /> All ground water monitoring wells will be allowed to set for at least 24 hours following their <br /> completion Each well will be developed by alternately surging and pumping using a manual <br /> surge block and 12 volt submersible pump Well development will continue for at least one hour <br /> or until the field geologist determines that the water is reasonably clear and free of silt and <br /> sediment All well development water will be containerized on-site in metal 55 gallons drums for <br /> remediation and/or disposal pending laboratory results The QA/QC Plan contains information on <br /> ' these procedures (Appendix A) <br /> Sampling of monitoring wells will proceed no sooner than 24 hours following well development <br /> ' AGS will collect ground water samples from each monitoring well after purging between three <br /> and five well volumes of ground water from each well During purging, ground water quality <br /> parameters will be monitored and recorded on the appropriate well sampling forms Wells will be <br /> ' purged until water quality stabilization has occurred Stabilization will have been reached when <br /> two consecutive temperature, pH, and conductivity readings do not vary by more than 10% <br /> Purged well water will be containerized and stored on-site in metal 55 gallon drums pending <br /> ' analytical results The QA/QC Plan contains information on these procedures (Appendix A) <br /> ' After well purging has been completed, a ground water sample will be collected Samples will be <br /> collected by lowering a clean disposable polyethylene bailer attached to new poly twine into the <br /> well Collected ground water will be transferred into two laboratory provided clean glass VOA <br /> vials Samples collected in VOA vials will be inverted to check for bubbles and refilled if found <br /> Properly collected samples will be labeled with the location, date and time of collection, and <br /> immediately placed into a cooler chilled to 4° Celsius All samples will be handled under chain of <br /> custody procedures for delivery to the analytical laboratory Section 3 3 3 below describes the <br /> analytical procedures in greater detail <br /> 3.3.3 Laboratory Analysis of Ground Water Samples <br /> All ground water samples collected for analysis will be stored in a cooler chilled to 4° Celsius and <br /> ' shipped under strict chain of custody protocol to the analytical laboratory The samples will be <br /> analyzed in Modesto, California by GeoAnalytical Laboratories, a California State certified <br /> analytical laboratory for the following constituents <br /> ' • TPH- gasoline, Method 5030/LLJFT <br /> g <br /> ' detection limit 0 05 mg/L <br /> Benzene, Toluene, Ethyl Benzene and Total Xylenes (BTEX), EPA Method 602 <br /> ' detection limits 0 3 pg/L BTE, 0 6 pg/L X <br /> American Geological Services,Inc. <br /> CA95DE-029 <br /> ' 11 <br />