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5 <br /> Well Development and Groundwater Samples. Each well will be <br /> developed by surging and pumping until clean, sediment-free water is <br /> produced from the well. The length of development time will vary <br /> depending upon field conditions. Prior to, and after development, <br /> the thickness of free product, if any, will be gauged. Water <br /> produced during development will be contained on site. ARCO will be <br /> responsible for the disposal of water and product collected. <br /> Following proper development of each well, a nitrogen-driven <br /> bladder pump or stainless steel bailer will be used to evacuate an <br /> additional amount of water before samples are taken. The amount of <br /> water evacuated will be defined by the stabilization of pH and EC <br /> readings for three consecutive measurements taken 5 minutes apart. <br /> When pH and EC have been determined to have stabilized, water samples <br /> will be collected in volatile organic analyses bottles. These <br /> bottles will be filled directly from the discharge line of the <br /> bladder pump, and will be filled to the brim. A Teflon-lined cap <br /> (septa) will be placed on each bottle, and the bottle will be checked <br /> to determine that no air bubbles remain within. Water samples will <br /> be analyzed for BTX (EPA 602) , total petroleum fuel hydrocarbons (EPA <br /> 8015) , total lead, and general minerals. <br /> All water samples will be labeled and stored as described in the <br /> Soil Samples section above, and transported to the Brown and Caldwell <br /> laboratory in Emeryville within 48 hours. <br /> Continued Groundwater Monitoring and Sampling <br /> All groundwater monitoring wells will be monitored monthly for <br /> water levels. Selected wells will be analyzed quarterly for BTX <br /> (EPA 602) . The groundwater samples will be collected and analyzed <br /> according to the methods described in the Sampling Procedures section <br /> of this work plan. <br /> The water discharged from the recovery system will be sampled <br /> quarterly and analyzed for EPA 602. The groundwater samples will be <br /> collected directly from the discharge line of the recovery well. <br /> Prior to sample collection, the system will be allowed to pump for <br /> 15 to 30 minutes. The water samples will be collected and analyzed <br /> according to the methods described in the Sampling Procedures section <br /> of this work plan. <br /> Decontamination Procedures <br /> To prevent cross-contamination, soil sampling equipment, bailers, <br /> and all pumps and their related tubing will be washed with <br /> laboratory-grade detergent, rinsed with tap water , and rinsed with <br /> deionized water before sampling and development. Downhole drilling <br /> equipment and the development pump will be steam-cleaned before and <br /> between use at each borehole. <br />