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Depth to water is recorded to the nearest 0.01 foot in the field logbook. The groundwater <br /> elevation at each monitoring well is calculated by subtracting the measured depth to water from <br /> the surveyed elevation of the top of the well casing. The total depth of the well is then measured <br /> in the monitoring wells scheduled for sampling by lowering the sounder to the bottom of the <br /> well. The total depth of the well, used to calculate purge volumes and to determine whether the <br /> well screen is partially obstructed by silt, is recorded to the nearest 0.5 foot in the field 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 /> Field measurements are recorded on a Water Sample Field Data Sheet (Figure A-2) contained in <br /> a waterproof field logbook. Field data sheets are reviewed by the sampling coordinator after the <br /> sampling event is completed. <br /> The pH, specific conductance, and temperature meter is calibrated each day before beginning <br /> field activities. The calibration is also checked once each day to verify meter performance. Field <br /> meter calibrations are recorded on the Water Sample Field Data Sheet. <br /> Equipment Cleaning <br /> Sample bottles, caps, and septa used in sampling for volatile and semivolatile organics are triple <br /> rinsed with high-purity deionized water. After being rinsed, sample bottles are dried overnight at <br /> 200°C. Sample caps and septa are dried overnight at 60°C. All sample bottles, caps, and septa are <br /> protected from solvent contact between drying and actual use at the sampling site, and are used only <br /> once and discarded after analysis is complete. <br /> Plastic bottles and caps used in sampling for metals are soaked overnight in a 1 percent nitric <br /> acid solution. The bottles and caps are then triple rinsed with deionized water and air dried <br /> before being used at the site. Plastic bottles and caps used in sampling for general water quality <br /> parameters are not routinely washed. All plastic bottles and caps are constructed of linear <br /> polyethylene or polypropylene. 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 is disassembled and cleaned thoroughly with detergent water and then steam <br /> cleaned with deionized water. Any parts that may absorb contaminants, such as plastic pump <br /> valves, bladders, etc., are cleaned as described above or replaced. The inside surfaces of the <br /> positive displacement (bladder) pump tubing are cleaned by heating the tubing overnight at <br /> 120°C with a low-flow,inert air source. t <br /> Once the bladder pump is cleaned and reassembled, a pump blank is obtained by pumping <br /> organic-free water through the bladder pump assembly. The pump effluent is sampled and <br /> A NAMiscellaneous\Groundwater Info-All Sites\SAP AppendixA.doc <br /> A-2 <br />