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Ithe bottom of the augers and the well will be constructed within the <br /> hollow-stem augers <br /> The wells will be constructed using 2-inch diameter flush-threaded, <br /> schedule 80, 0 020-inch slotted PVC well screen and blank casing The <br /> well casing will be lowered through the augers and #2112 filter pack sand <br /> will be placed in the annular space between the well casing and the <br />' borehole from the bottom of the boring to approximately 2-feet above t h e <br /> screened interval For the wells installed deeper than 20-feet bgs, t h e <br /> wells will be developed using a surge block and bailer to settle the sand <br />' prior to placing the sanitary seal Well development water will b e <br /> contained in 55-gallon steel drums, labeled and stored on-site until <br />' proper off-site disposal can be arranged Approximately 1 to 2-feet o f <br /> time release (coated) bentonite pellets will be placed on top of the sand <br /> pack prior to placing the cement sanitary seal Cement mixed with 3 to 5 <br />' percent bentonite powder by volume will be used to fill the annular space <br /> between the bentonite layer and the surface to prevent surface water <br /> from infiltrating into the well and to prevent conduits for the migration of <br />' contamination from shallow groundwater into deeper zones The cement <br /> will be placed by tremae pipe in all situations where the seal is placed <br /> below the water table The well heads will be protected with a locking <br /> well plug beneath an at-grade, traffic-rated well box (See Figure 8 - <br /> Typical Monitoring Well) <br /> All monitoring wells will be screened with screens no longer than 15-feet <br /> in length Each monitoring well will have only one screened interval <br /> TASK 3 - DEVELOP THE MONITORING WELLS <br />' ASE will develop each monitoring well using multiple episodes of surge <br /> block agitation and evacuation with pumps and/or bailers At least t e n <br /> (10) well casing volumes of groundwater will be removed during <br />' development, and evacuation will continue until the water is reasonably <br /> clear <br /> The monitoring wells installed deeper than 20-feet bgs will be developed <br /> prior to placing the cement sanitary seal The shallow monitoring wells <br />' will be developed after waiting at least 72 hours after placing the cement <br /> sanitary seal <br />' Purged groundwater will be stored on-site in sealed and labeled 55-gallon <br /> steel drums until off-site disposal can be arranged <br /> Frank's One Stop Workplan — September 2003 <br />' -15- <br />