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ame& <br /> �+ 3.4.4 Well Development and Survey <br /> Once the well installation activities have been completed and the grout has cured a minimum <br /> of 24 hours, the newly installed wells will be developed by surging, bailing, and/or.pumping. <br /> During development, turbidity pH, specific conductance, and temperature of the return water . <br /> will be measured. Drawdown and recovery will be measured during and at the end of the <br /> development process, respectively, using an electric sounder. Well development will proceed <br /> until the return water is clear. <br /> Caltrans will survey the well locations and elevations relative to mean sea level and AMEC will <br /> upload the new survey data to Geotracker. <br /> 3.4.5 Groundwater Sampling <br /> A minimum of 24 hours after well development and prior to the initiation of the AS pilot test, a <br /> baseline groundwater monitoring and sampling event will be conducted. Approximately 2 <br /> r weeks following the completion of the AS pilot test, the pilot test wells will be sampled again. <br /> !L� Groundwater levels will be gauged in all new wells and in VW-1 and VW-2. Low-flow sampling <br /> procedures will be used to collect groundwater samples (Puts & Barcelona, 1996). <br /> Groundwater samples collected from each well will be analyzed for the following constituents <br /> as shown in Table 1. <br /> • TPHg by U.S. EPA Method 8015M; <br /> • TPHd by U.S. EPA Method 8015M; and <br /> • BTEX, fuel oxygenates compounds (Di-isopropyl ether, Ethyl tert-butyl ether, Tert- <br /> amyl methyl ether, Tert-Butanol, Methyl tert-butyl ether), and lead scavengers <br /> f (1,2-Dibromoethane and 1,2-Dichloroethane) by U.S. EPA Method 8260B; and <br /> L <br /> • Dissolved iron by U.S. EPA Method 60106.. <br /> The presence of dissolved iron in groundwater can reduce the permeability of the saturated <br /> zone in soils during air sparging operations. When dissolved iron is exposed to oxygen, it is <br /> oxidized to insoluble iron (Fe 3+)oxide which can precipitate within the saturated zone, <br /> reducing soil pore space and therefore reducing permeability and groundwater flow. <br /> 3.4 QUALITY ASSURANCE SAMPLING AND ANALYSIS <br /> Quality Assurance/Quality Control procedures will include: <br /> • Adherence to protocols for field sampling and decontamination procedures; <br /> AMEC Geomatrix, Inc. <br /> P:\Project\14000s\14443—Caltrans\TO10\11000 PLANS\AS WP_March M0\AS WP.doc 10 <br />