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APPENDIX B <br />Monitoring and Sampling Procedures <br />McBillin Real Estate Investment <br />2154 South El Dorado Street, Stockton, California <br />STATIC WATER LEVEL MEASUREMENTS <br />Before sampling and during ground water monitoring, static water levels will be measured <br />at all wells using an electric water level indicator. Water level data is recorded to the <br />nearest 0.01-foot from a reference point marked on the top of the PVC well casing. <br />WELL PURGING <br />Subsequent to measurement of depth to water and prior to sampling, each well is purged <br />to ensure samples are representative of the formation, rather than standing water in the <br />well casing. Wells are purged using a Waterra inertial pump and dedicated 5/8-inch plastic <br />tubing. <br />Wells are purged until a minimum of three casing-water volumes are removed from the well <br />and/or the field-measured ground water parameters (pH, temperature, and conductivity) <br />are stabilized. However, if a well is purged dry prior to evacuating three casing volumes, <br />a sample is collected following 80 percent recovery of ground water within the well, or after <br />a minimum of one hour, but within eight hours, of purging procedures. <br />SAMPLE WITHDRAWAL <br />Water samples are collected from each monitoring well using either an interia pump with <br />dedicated plastic/Teflon tubing or a disposable polyethylene bailer. Bailers are disposed <br />of after a single use (sample) and require no decontaminating; plastic tubing used with the <br />inertia pump is either dedicated to each well point or changed at each sampling event, <br />thereby minimizing cross contamination due to sampling devices. Samples are drawn and <br />collected in such a manner that agitation and exposure of the ground water to the <br />atmosphere is minimal. <br />SAMPLE HANDLING <br />Ground water samples are collected into laboratory-supplied 40-ml volatile organic analysis <br />(VOA) vials without preservative and, if appropriate, one-liter amber glass containers <br />without a preservative; the samples are collected with no visible air bubbles present in the <br />vials after filling and capping. Following collection, samples are appropriately labeled, <br />placed on ice, and kept in a cooler until delivered to Cal Tech Environmental Laboratories <br />Advanced GeoEnvironmental, Inc.