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A-2 <br /> 1.2 Well Evacuation and Development <br /> ' After the static water level in a well was determined and prior to collection of a ground water <br /> sample, stagnant water was removed from the well casing and the surrounding gravel pack by <br /> ' bailing, pumping, or with a vacuum truck At least three casing volumes of water were removed <br /> from each well from which a sample was collected The volume of water in the casing was <br /> determined from the known elevation of the water surface, the well bottom elevation (as <br /> ' measured when the well is installed), and the well diameter <br /> If the well was bailed or pumped during purging, samples were collected and field analyzed for <br /> pH, temperature, and specific conductance The well was considered stabilized when repeated <br /> readings of the following parameters were within the ranges indicated as follows <br /> ' • Specific conductance ±10 percent of the reading range <br /> • pH ±0 1 pH unit <br /> • Temperature ±0 50 C <br /> ' After stabilization, and after at least three well volumes were evacuated a sample was collected <br /> ected <br /> for analysis. The field container used for well stabilization measurements, and the pH, <br /> ' temperature, and conductivity probes were rinsed between wells with deionized water <br /> All purge water was containerized and properly handled and documented for disposal If the <br /> ' containers were stored on site, a label specifying the date of purging, source, and the known or <br /> suspected nature of the contents was affixed to each container <br /> ' 1.3 Sample Collection, Preservation, and Handling <br /> After purging, a new polyethylene disposable bailer was used to collect samples for analysis <br /> The bailer was attached to a new disposable rope and lowered slowly into the water to avoid <br /> agitation of the collected sample Containers for volatile organics analyses were filled <br />' completely so no airspace remained in the vial after sealing <br /> All sample containers were prewashed and prepared at the analyzing laboratory in accordance <br /> with quality assurance/quality control protocols of the laboratory Only sample containers <br /> appropnate for the intended analyses were used <br />' After sample collection, the samples were placed into coolers with ice packs Internal <br /> temperature of the cooler was maintained at approximately 4 degrees Celcius Samples were <br /> kept in coolers during transport to the analyzing laboratory <br />