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Volume in gallons per foot of cylinder = 5.872 <br />Using the default static water level of 30 feet and a total depth or 86 feet (86-30 = 56 feet) <br />the total water column is calculated to be 56 feet. Using a conversion of 5.782 gallons <br />per foot gives a total volume of 324 gallons of water in the well (56 x 5.782 = 324). <br />Multiplying the volume of water by three: 3 x 324 gallons = 972 gallons <br />A minimum of 972 gallons of water should be removed unless an accurate measurement <br />of the static water level is made and calculations completed and recorded in sampling <br />sheets or logbook. The accurate measurement of static water should be subtracted from <br />the total depth of 86 feet and the resulting depth of water column multiplied by 5.872 <br />gallons per foot. To obtain the minimum three boring volumes of water to be purged <br />prior to sampling multiply the total volume of the column of water by 3. <br />Pump Time <br />Taking the total volume of water to be purged and multiplying by the pump rate will <br />determine the amount of time to allow the pump to operate. Using the value of 972 <br />gallons used in the example above and the lowest of the two pump rates discussed for the <br />well the following time period is calculated for purging a minimum of three casing <br />volumes from the well. <br />Three casing volumes = 972 gallons <br />Pump rate from well permit = 45 gallons per minute <br />Time for pumping = 972 gallons / 45 gallons per minute = 22 minutes <br />The pump will be allowed to operate for a minimum of 22 minutes for purging. <br />During the last 5 to 8 minutes of pumping samples will be taken to determine the <br />stability of water parameters as discussed below in the water sampling section. <br />4 Sampling Method <br />After obtaining the static water level and purging the well the following sampling <br />procedures will be followed. <br />1. Prepare for the sampling event as stated above. <br />2. Wearing clean disposable vinyl gloves take the sample by placing the sample <br />containers into the stream of water with pump operating with the lowest <br />volume possible and the least amount of agitation. Hold the sample container <br />at a 45-degree angle underneath the water stream. Fill the bottle to the top. <br />Hold the bottle cap in your hand with topside up and not touching the inside of <br />6