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A-3 <br /> closed at each end with a Teflon® sheet and plastic caps. The soil sample is collected, labeled, and <br /> handled according to the Quality Assurance Plan. <br /> Ground Water and Liquid-Phase Petroleum Hydrocarbon Depth Assessment <br /> A water/hydrocarbon interface probe is used to assess the liquid-phase petroleum hydrocarbon (LPH) <br /> thickness, if present, and a water level indicator is used to measure the ground water depth in <br /> monitoring wells that do not contain LPH. Depth to ground water or LPH is measured from a datum <br /> point at the top of each monitoring well casing. The datum point is typically a notch cut in the north <br /> side of the casing edge. If a water level indicator is used, the tip is subjectively analyzed for <br /> hydrocarbon sheen. <br /> Subjective Analysis of Ground Water <br /> Prior to purging, a water sample is collected from the monitoring well for subjective analysis. The <br /> sample is retrieved by gently lowering a clean, disposable bailer to approximately one-half the bailer <br /> length past the air/liquid interface. The bailer, is then retrieved, and the sample contained within the <br /> bailer is 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 <br /> purge water has stabilized and a minimum of three well volumes of water have been removed. If three <br /> well volumes can not be removed in one and a half hours time the well is allowed to recharge to 80 <br /> percent of original level. After recharging, a ground water sample is then removed from each of the <br /> wells using a disposable bailer. The water sample is collected, labeled, and handled according to the <br /> Quality Assurance Plan. Water generated during the monitoring event is disposed of according to the <br /> regulatory accepted method pertaining 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 <br /> in a suitable container, preserved correctly for the intended analysis, and stored prior to analysis for no <br /> longer than the maximum allowable holding time. Details on the procedures for collection and <br /> handling of samples used on this project can be found in this section. <br /> CL006.KS <br />