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that do not contain-LPH. Depth to ground water or LPH is measured from a datum point at the top of each <br /> monitoring well casing. The datum point is typical a notch cut in the north side of the casing edge. If a <br /> water level indicator is used,the tip is subjectively analyzed for hydrocarbon sheen. <br /> Subiective Analysis of Ground Water <br /> Prior to purging, a water sample is collected from the monitoring well for subjective assessment. The <br /> sample is retrieved by gently lowering a clean, disposable bailer to approximately one-half the bailer length <br /> past the air/liquid interface. The bailer is then retrieved, and the sample contained within the bailer is <br /> examined for floating LPH and the appearance of a LPH sheen. <br /> Monitoring Well Purging and Sampling <br /> Monitoring wells are purged using a pump or bailer until pH, temperature and conductivity of the purge <br /> water has stabilized and a minimum of three well volumes of water has been removed. If three well <br /> volumes can not be removed in one half an hour of time,the well is allowed to recharge to 80 percent of the <br /> original level. After recharging, a ground water sample is then removed from the well using a disposable <br /> bailer. The water sample is collected, labeled and handled according to the Quality Assurance Plan. Water <br /> generated during the monitoring event is disposed of according to the regulatory accepted method pertaining <br /> to the site. <br /> QUALITY ASSURANCE PLAN <br /> General Sample Collection and Handling Procedures <br /> Proper collection and handling are essential to ensure the quality of a sample. Each sample is collected in a <br /> suitable container, preserved correctly for the intended analysis and stored prior to analysis for no longer <br /> than the maximum allowable holding time. Details on the procedures for collection and handling of <br /> samples used on this project can be found in this section. <br /> Water Sample Collection for Volatile Organic Analyses <br /> For volatile organic analyses(VOA),the water sample is decanted into each VOA vial in such a manner so <br /> that there is no meniscus at the top of the vial. A cap is quickly secured to the top of the vial. The vial is <br /> inverted and gently tapped to see if air bubbles are present. If none are present, the vial is labeled and <br /> refrigerated according to Soil and Water Sample Labeling and Preservation procedures. <br /> 6 <br />