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through the augers to form an annular seal A cement mixture will be used to fill the annular <br /> space to one foot below grade Traffic rated, flush-mounted well boxes will be installed at a <br /> height of approximately I-inch above grade to minimize the potential for surface runoff entering <br /> the well. <br /> 3.7 Well Development <br /> £ach groundwater monitoring well will be developed using a surge block. Pumping and/or bailing <br /> will be conducted to remove at least three well volumes of groundwater or until the removed <br /> groundwater is essentially free of sediment. During purging, values of pH, conductivity and <br /> temperature will be monitored and recorded. <br /> 3.8 Groundwater Sampling <br /> In the event that the wells are not sampled within 24 hours of well development and purging, each <br /> well will be purged with a bladder or submersible pump until at least three well volumes have <br /> been removed. Groundwater samples will be collected after the well has sufficiently equilibrated <br /> to static groundwater levels Groundwater samples will be collected using a teflon or new <br /> disposable bailer and placed in the appropriate containers in an approved manner. The samples <br /> will be placed in a cooler at 4 degrees centigrade or less and transported to a laboratory under <br /> proper chain of custody documentation. <br /> . 3.9 Groundwater Analyses <br /> Analyses of the groundwater will be performed by a California certified laboratory in accordance <br /> with State guidelines and EPA protocol. The groundwater samples will be analyzed for TPH, <br /> BTEX and total lead using EPA methods 8015M, 8020 and 7421, respectively. In addition to <br /> samples from each well, one equipment blank and one field duplicate will be collected and <br /> analyzed for the same chemical constituents. <br /> 3.10 Vapor Extraction <br /> Vapor treatability testing will be performed on the three BEI and possibly one or both of the off <br /> site monitoring wells, to assess whether soils contain vapor phase constituents, and to evaluate the <br /> site suitability for using vapor extraction as a remediation technology. The testing will consist of <br /> applying a vacuum on the well head and measuring flow and vacuum values for that well, while <br /> monitoring nearby wells for vacuum. Vapor samples will be collected for TPH and BTEX <br /> analyses using EPA methods 8015 and 8020, respectively, or equivalent. <br /> 4.0 QUALITY ASSURANCE PLAN <br /> The following sections describe field and analytical quality-assurance procedures to be followed <br /> during the described investigation. <br /> • 5023;2 5 <br />