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3.8 Groundwater Monitoring and Sampling <br /> Groundwater at the newly installed monitoring well will be monitored and sampled at least 24 <br /> hours after development of the well. Depth to groundwater will be measured from the top of <br /> casing (TOC) to the nearest 0.01-foot using a Solinst water level meter. The monitoring well will <br /> be sampled using low-flow purging and sampling techniques. A bailer will be slowly lowered to a <br /> depth approximately five feet below the water table to minimize mixing of water stored within the <br /> casing. The bailer will be used to remove about 3 to 5 well volumes. The water level will be <br /> monitored during purging to limit draw-down to 4 inches. Periodically during purging the pH, <br /> temperature, and electrical conductivity parameters will be measured. Groundwater will be <br /> considered stabilized and representative of the aquifer when three consecutive measurements are <br /> within±0.1 for pH, ±3% for electrical conductivity, and± 10% for temperature. <br /> After purging, a groundwater sample will be collected directly from the pump discharge into two <br /> 40-milliliter VOA vials. Care will be to verify that headspace or bubbles do not exist and each <br /> VOA vial will be sealed using a Teflon®-lined lid. The samples will be labeled and placed in an <br /> iced cooler maintained at 4° Centigrade, and accompanied with a chain- of-custody document for <br /> transport to the analytical laboratory. <br /> All downhole equipment will be cleaned prior to use and between wells by washing using an <br /> Alconox solution and rinsing with clean potable water. <br /> Environmental/LNC/Workplan/Appendix 2.wpd 8 <br />