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GROUNDWATER MONITORING WELL SAMPLING AND PURGING PROTOCOL <br /> Prior to sampling the groundwater monitoring wells, the wells are open to the atmosphere for <br /> approximately one hour to allow for the groundwater to adjust to the open barometric pressure <br /> The depth to groundwater is then measured in the well, followed by electrical conductivity, <br /> pH,and temperature readings of the groundwater These parameters,along with the volume of <br /> the purged water (described below) and time, are recorded on the field sampling and purging <br /> form <br /> The volume of water in the monitoring well is calculated using the following equation <br /> Feet of water in well x 0163 for 2 inch diameter well = Volume water in gallons <br /> Feet of water in well x 0 653 for 4 inch diameter well = Volume water in gallons <br /> Where the feet of water in well is calculated by subtracting the depth to groundwater from the <br /> total depth of the well <br /> The volume of water to be removed is estimated by multiplying the volume of water in gallons <br /> by three to four well volumes This value will be recorded on the field form <br /> The pH, temperature, and electrical conductivity will be monitored and recorded between each <br /> well volume removed, and must be within 10% of the previous reading prior to sampling The <br /> I , <br /> groundwater level in the monitoring well is allowed to recover to 80% of the original depth <br /> prior to sampling <br /> I I <br /> A minimum of four well volumes (where four volumes were available) were removed using a <br /> truck-mounted bailer prior to collecting the water sample The removed water was placed in I' <br /> I ' <br /> steel storage barrels with bolt-on lids, which where retained on site After the well had <br /> I ' E <br /> stabilized, water samples were collected using a disposable,bailcr with a check valve I <br /> ` I I" I <br /> I " I <br />