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A cement/bentonite slurry grout will be used to seal the borings from the top of the bentonite seal <br /> to the surface. All wells will be completed above the existing grade using 8 to 10 inch diameter <br /> steel well monuments set in concrete. Each well monument will extend approximately 30 inches <br /> above the ground surface and be secured with a padlock. Each well head will be secured with a <br /> water-tight well cap. A schematic diagram of the proposed monitoring well construction is <br /> i <br /> included in Appendix C. <br /> All monitoring wells will be drilled by a California State licensed drilling contractor with <br /> experience in environmental projects. Soil drill cuttings generated during soil boring and <br /> monitoring well installation will be stored on-site. <br /> Prior to drilling each well boring, all drilling and sampling equipment will be thoroughly <br /> decontaminated as specified in the SOP (Appendix A). Monitoring well locations and elevations <br /> to the point of measurement (POM) scribed in the well casing will be surveyed by a licensed <br /> California surveyor to 0.01 foot accuracy and locations and elevations will be plotted on a site <br /> plan map for inclusion in the report. <br /> 3.2.2 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 submersible pump. Well development will continue for at least one hour or until <br /> the field geologist determines that the water is reasonably clear and free of silt and sediment. <br /> The SOP and QA/QC Plan contain information on these procedures (Appendix A). <br /> Sampling of monitoring wells will proceed after well development. AGS will collect ground <br /> water samples from each monitoring well after purging between three and five well volumes of <br /> ground water from each well. During purging, ground water quality parameters will be <br /> monitored and recorded on the appropriate well sampling forms. Wells will be purged until <br /> water quality stabilization has occurred. Stabilization will have been reached when two <br /> consecutive temperature, pH, and conductivity readings do not vary by more than 10%. Purged <br /> well water will be containerized and stored on-site in metal 55 gallon drums pending analytical <br /> results. The SOP and QA/QC Plan contain information on these procedures (Appendix A). <br /> After well purging has been completed, a ground water sample will be collected from each well. <br /> Samples will be collected by lowering a clean disposable polyethylene bailer attached to new <br /> poly twine into the well. Alternatively, the samples may be collected using a decontaminated <br /> PVC bailer. Ground water sampled from each well will be transferred into one laboratory <br /> provided clean glass amber liter bottles. Properly collected samples will be labeled with the <br /> location, date and time of collection, and immediately placed into a cooler chilled to 4° Celsius. <br /> All samples will be handled under chain of custody procedures and delivered to the analytical <br /> laboratory within 48 hours. The samples will be analyzed in Modesto, California by <br /> GeoAnalytical Laboratories, a California State certified analytical laboratory. Section 3.2.3 <br /> listed below describes the analytical procedures in greater detail. <br /> American Geological Services, Inc. <br /> CA96DE-055 <br /> 6 <br />