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0 3.0 WELL SPECIFICATIONS Each of the nine monitoring wells are to be installed using the guidelines set forth in the Comprehensive Field Work Plan(Radian International, 1998).The well design specifications of the proposed nine monitoring wells are shown in Tables 3-1. Table 3-1 Estimated WeB Specifications* Estimated Casing Casing Estimated Well Estimated Boring ID Length Depth Diameter Material Slot Size Screen Well n LM153A 60 6-inch SCH 40 PVC 0.010 20 feet LM154B 100 6-inch SCH 40 PVC 0.010 10 feet LM155A 60 6-inch SCH 40 PVC 0.010 25 feet LM156B 100 6-inch SCH 40 PVC 0.010 15 feet LM157A 60 6-inch SCH 40 PVC 0.010 25 feet L.M159A 50 6-inch SCH 40 PVC 0.010 25 feet LM159B 100 6-inch SCH 40 PVC 0.010 10 feet LM160A 50 6-inch SCH 40 PVC0.010 25 feet LM 161B 100 6-inch I SCH 40 PVC 1 0.010 15 feet * Well specifications are dependent upon the lithology encountered during drilling 4.0 WELL MATERIALS 4.1 Well Casing The well casing will be 6-inch nominal diameter Schedule 40 PVC pipe with flush threads for the monitoring wells.The casing surface will be free of solvents, oils,grease,paint, and dirt and will be certified clean from the factory or steam-cleaned on site prior to installation. Sections of casing will be received from the supplier wrapped in polyethylene protective wrappers with sealed ends in order to limit exposure to potential contaminants. Casing will not be removed from the wrapping until immediately before it is to be placed in the boring. 4.2 Well Screen The well screen will be 6-inch nominal diameter,Schedule 40 PVC slot screen with flush threads for all the monitoring wells.All screen openings will widen inward so as to be non-clogging.The slot size will be compatible with the filter pack that will surround the screen;slot size and filter pack will be determined based on pilot boring lithologies. The well screen will be of sufficient size and design to hold back and support the filter pack and in-situ soils surrounding the screen.The well screen surface will be free of solvents,oils,grease,paint,and dirt and will be certified clean from the factory or steam-cleaned on site prior to installation.The well screen will have smooth,sharp-edged openings free of burrs,chipped edges, or broken pieces on the interior and exterior surfaces of the pipe. Sections of the screen will be received from the supplier wrapped in polyethylene protective wrappers with sealed ends in order to limit exposure to potential contaminants.Wrapping will not be removed until screen is to be used. 4.3 Filter Pack The filter pack material will be composed of round,hard, water-worn siliceous sand,free of flat or elongated pieces, organic matter, or other foreign matter.All filter pack material will be protected from contamination prior to placement by either storing it in plastic-lined paper bags or in a location protected from the weather and contamination on plastic sheeting. All filter pack will be placed in the annular space in the borehole by using a 2-inch tremie pipe. Once the filter pack is in place the driller will develop the interval until the no measurable decline in the filter pack is measured. All water used placed into the borehole during the construction process will be accounted for and removed before the well is developed.