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Water levels will be measured with an electric sounder. The electric sounder is a transistorized <br /> instrument that uses a reel-mounted, two-conductor, coaxial cable that connects the control panel <br /> 1 to the sensor. Cable markings are stamped at 1-foot increments. The water level will be measured <br /> by lowering the sensor into the monitoring well. A low-current circuit is completed when the <br /> sensor contacts the water, which serves as an electrolyte. The current is amplified and fed into an <br /> indicator light and audible buzzer, signaling when water has been contacted. A sensitivity control <br /> will compensate for highly saline or conductive water. The electric sounder will be <br /> decontaminated by rinsing with deionized water after each use. <br /> Depth to water will be recorded to the nearest 0.01 foot in the field logbook. The groundwater <br /> elevation at each monitoring well will be calculated by subtracting the measured depth to water <br /> 1 from the surveyed elevation of the top of the well casing. The total depth of the well is then <br /> measured in the monitoring wells scheduled for sampling by lowering the sensor to the bottom of <br /> the well. The total depth of the well, used to calculate purge volumes and to determine whether <br /> the well screen is partially obstructed by silt, will be recorded to the nearest 0.5 foot in the field <br /> logbook. <br /> SAMPLE COLLECTION <br /> Sample collection procedures include equipment cleaning, water level and total well depth <br /> measurements, well purging and sampling, spring (or surface water) sampling, leachate sampling, <br /> and lysimeter sampling. <br /> Equipment Cleaning <br /> Sample bottles,caps, and septa used in sampling for volatile and semivolatile organics will be triple <br /> rinsed with high-purity deionized water. After being rinsed, sample bottles will be dried overnight <br /> at 200°C. Sample caps and septa will be dried overnight at 60°C. Sample bottles, caps, and septa <br /> will be protected from solvent contact between drying and actual use at the sampling site. Sample <br /> bottles,caps, and septa will be used only once and discarded after analysis is complete. <br /> Plastic bottles and sampling caps used in for metals will be soaked overnight in a 1 percent nitric <br /> P g <br /> acid solution. The bottles and caps will then be triple rinsed with deionized water and air dried <br /> before being used at the site. All plastic bottles and caps will be constructed of linear <br /> polyethylene or polypropylene. Plastic bottles and caps will be used only once and discarded after <br /> analysis is complete. <br /> Plastic bottles and caps used in sampling for general water quality parameters are not routinely <br /> washed. They are used only once and discarded after analysis is complete. <br /> Before the sampling event is started, equipment that will be placed in the well or come in contact <br /> with groundwater will be disassembled and cleaned thoroughly with detergent water and then <br /> steam cleaned with deionized water. Any parts that may absorb contaminants, such as plastic <br /> pump valves, bladders, etc., will be cleaned as described above or replaced. The inside surfaces <br /> SAO.SAWES\S&APROC.DOC-954:1 2 <br />