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WELL DEVELOPMENT AND SAMPLING PROCEDURES <br /> All development, purging, and ground water sampling equipment was cleaned prior to use <br /> to minimize cross-contamination between wells. All equipment in contact with ground water <br /> was triple-rinsed prior to each sampling event in successive baths consisting of an Alconox <br /> solution, tap water, and deionized water. The monitoring well was developed by removing <br /> 10 casing volumes and surged in accordance with Regional Water Quality Control Board, <br /> Central Valley Region (RWQCB), protocol. <br /> All wells were inspected for the presence of free product using an electronic interface probe <br /> prior to purging. Prior to sampling, monitoring wells were purged of 3 to 4 casing volumes <br /> and pH, temperature, and electroconductivity parameters stabilized. Ground water samples <br /> were collected by lowering a 2-inch-diameter, bottom-511, disposable polyethylene bailer <br /> below the air/water interface in the well. The samples were carefully transferred from the <br /> bailer to zero-headspace 40-milliliter and 1-liter glass containers fitted with Teflon-sealed <br /> caps. All 40-milliliter samples were inverted to ensure that entrapped air was not present. <br /> Each sample was labeled with sample number, well number, sample date, and geologist's <br /> initials. The samples remained on ice prior to and during transport to a California-certified <br /> laboratory for analysis. The samples were handled in accordance with proper chain of <br /> custody documentation. The purged water was pumped into barrels prior to disposal or <br /> recycling at an appropriate waste disposal facility. <br />