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to approximately I foot above the screened interval A sanitary seal consisting of 2 feet of hydrated bentonite chips will be placed on top of the gravel pack, and bentonite cement slurry will fill the remaining annulus to surface grade The monitor well will be completed at surface grade with a water tight traffic-rated street box set in cement, and a water tight, locking well cap A typical groundwater monitor well construction diagram is shown on Figure 5 45 Monitor Well Development_.and Surveying After installation, the monitor wells will be checked for floating liquid hydrocarbon by lowering a clean teflon bailer down the well and collecting a sample at the groundwater interface If the well contains floating liquid hydrocarbon it will not be developed Wells not containing floating liquid hydrocarbon will be developed by using a surge block and PVC bailer to alternately surge the screened portion of the well bore and purge the sediment laden water Development will continue until five to ten well volumes of groundwater have been removed, and/or the water produced is relatively sediment free For each morutor well installed at the site, the top of casing of the completed groundwater monitor wells will then be surveyed to a baseline datum and accurately located on a site map by a licensed professional surveyor 46 Groundwater Monitoring and Sampling A depth-to-groundwater measurement will be obtained from the groundwater monitor wells using a water level indicator graduated to 0 01 foot The depth to groundwater measurement will be converted to a groundwater elevation for the well If liquid hydrocarbons are present the well(s) will not be ' purged and sampled Following the check for liquid hydrocarbons, each well will be purged by hand bailing or pumping at least four weH volumes, or until the well goes dry After allowing the water level in the monitor well to recover to at least 80 percent of its static level, groundwater samples will be collected using a clean teflon bailer and subsequently be decanted in laboratory supplied sample vessels Samples will be tightly capped with zero headspace, then labelled with the sample number, sample time and date, and immediately placed on ice in an insulated cooler The sample will be logged onto a Chain-of-Custody 055LO1_XWPLL 9£COA 6 NOOPS-00]-0] Jy9 LIZ v I