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3.2.4.1 Bottles <br /> Specific bottles will be ordered from the analytical laboratory to collect the water <br /> samples. The laboratory will be notified they will be responsible for filtering dissolved <br /> samples prior to placing a bottle order. <br /> 3.2.4.2 Static Water Levels <br /> Static water levels in the wells will be measured and recorded using a water level well <br /> sounder prior to any pumping of the well. The measurement location at the top edge of <br /> the casing will be marked with permanent ink pen and should be touched up with fresh <br /> ink at each sampling event. All water levels, and observation well elevations should be <br /> measured to at least 0.01' (hundredth of a foot). <br /> 3.2.4.3 Purging <br /> Monitoring wells will be purged prior to sample collection. Either a low-flow submersible <br /> pump or polyurethane bailers will be used to purge the wells and collect samples, <br /> depending on the required purge volume. Pumps will be decontaminated prior to being <br /> placed in each well, whereas new bailers will be used and disposed of for each well. <br /> Removal of three well casing volumes will occur prior to sampling. The static volume of <br /> water in the well will be calculated using the following equation: <br /> V = r2h(0.163) <br /> Where <br /> V = static volume of water in well (in gallons) <br /> r = inner radius of well casing (in inches) <br /> h = length of water column (in feet)which is equal to the <br /> total well depth minus depth to water. <br /> 0.163 = a constant conversion factor that compensates <br /> for the conversion of the casing radius from inches to <br /> feet for 2-inch diameter wells and the conversion of <br /> cubic feet to gallons, and pi (A). This factor would <br /> change for different diameter wells. <br /> The purged volume of water will be measured using a five-gallon bucket to verify that the <br /> static volumes in the wells are evacuated prior to sample collection. Should the well purge <br /> dry prior to three casing volumes being removed, samples will be collected first draw after <br /> appropriate recharge. <br /> 14 <br />