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GROUNDWATER MONITORING AND SAMPLING PROCEDURES <br /> Groundwater Level Measurements <br /> ' Groundwater level measurements are obtained during each sampling event at each monitoring well using <br /> a Keck T11, interface probe (model KIR 89) water level indicator Depth to groundwater at each well is <br /> measured from the top and north side of the well casing Groundwater elevations are based on surveyed <br /> well head elevations established at designated measuring points at the top of each well casing The time <br /> and measurement are recorded by the technician on a groundwater monitoring field sheet (attached) <br /> Groundwater Purging <br /> ' Based on the groundwater level and the total depth of the well, the volume of water to be purged from <br /> the well is calculated before purging begins Approximately three to five well volumes are typically <br /> ' evacuated (purged) from each compliance well during well purging activities Groundwater is purged <br /> from each well using a pump and reel system consisting of a 2-inch, GrundfosTM,Redi-Flog, Model MP-1 <br /> submersible pump and teflonTM hose or equivalent Field data including pH, specific conductance, <br /> dissolved oxygen and groundwater temperatures are recorded during water evacuation from each <br /> monitoring well <br /> ' To minimize the likelihood of cross-contamination occurring, the pump and sampling equipment are <br /> ' • decontaminated prior to commencement of purging activities at the site and between each monitoring <br /> well In addition, the pump and reel system are decontaminated between samples using a non-phosphate <br /> detergent wash, tap water rinse, and final rinse using deionized water. Decontamination rinsate is <br /> containerized with the purge water Decontamination and purged water will be temporarily stored in an <br /> appropriate poly tank pending waste profiling, removal and disposal If possible, waste purge water will <br /> be removed using a certified vacuum truck <br /> ' Groundwater Sampling <br /> Groundwater samples are collected at each monitoring well using a new polyethylene, disposable bailer <br /> The groundwater recovered with the bailer is contained in laboratory-supplied sample containers as <br /> ' needed per each analytical method For quality control and quality assurance purposes, a trip blank is <br /> provided in the sample cooler by the analytical laboratory and duplicate, field blank, and/or equipment <br /> ' blank samples are collected at the site Upon collection, the sample date, time, and identification are <br /> written on the containers and on a chain-of-custody The sample containers are then placed in a sample <br /> cooler containing ice and transported, under strict chain-of-custody protocol, to a state-certified <br /> ' analytical laboratory for analysis <br /> 1 . <br />