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CAM B RIA <br /> Well Development <br /> Wells are generally developed using a combination of groundwater surging and extraction Surging <br /> agitates the groundwater and dislodges fine sediments from the sand pack After about ten minutes of <br /> surging, groundwater is extracted from the well using bailing, pumping and/or reverse air-lifting <br /> through an eductor pipe to remove the sediments from the well Surging and extraction continue until <br /> at least ten well-casing volumes of groundwater are extracted and the sediment volume in the <br /> groundwater is negligible This process usually occurs prior to installing the sanitary surface seal to <br /> ensure sand pack stabilization If development occurs after surface seal installation,then development <br /> occurs 24 to 72 hours after seal installation to ensure that the Portland cement has set up correctly <br /> All equipment is steam-cleaned prior to use and air used for air-lifting is filtered to prevent oil <br /> entrained in the compressed air from entering the well Wells that are developed using air-lift <br /> evacuation are not sampled until at least 24 hours after they are developed <br /> Groundwater Sampling <br /> Depending on local regulatory guidelines, three to four well-casing volumes of groundwater are <br /> purged prior to sampling Purging continues until groundwater pH, conductivity, and temperature <br /> have stabilized Groundwater samples are collected using bailers or pumps and are decanted into the <br /> appropriate containers supplied by the analytic laboratory Samples are labeled,placed in protective <br /> foam sleeves, stored on crushed ice at or below 4°C, and transported under chain-of-custody to the <br /> laboratory Laboratory-supplied trip blanks accompany the samples and are analyzed to check for <br /> cross-contamination An equipment blank maybe analyzed if non-dedicated sampling equipment is <br /> used <br /> F\TEMPLATEISOPSIWELLS-BORINGS-GW DOC <br /> Page 3 of 3 <br />