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I L- 11 <br /> based on inspection of the aquifer materials found at the interval to be screened. Two well screen <br /> sizes will be on hand in order to prevent delays. Well screens are anticipated to consist of 0.020- <br /> p <br /> inch slotted schedule 40 polyvinyl chloride(PVC). However, should the native soils include <br /> abundant clay and silt fines,0.010-inch slotted screens may be used. <br /> An approximately 2-foot-thick bentonite seal will be placed on top of the filter pack. The <br /> L <br /> remaining annulus will be grouted with a 3%bentonite/neat cement grout.The wells will be <br /> - completed with flush-mounted traffic-rated street caps.Well elevation will be surveyed by a <br /> licensed surveyor. Elevations will be measured for the ground surface and the top of casing.The <br /> center of the well will be located by latitude-and longitude. Survey data for all site wells will be <br /> LI updated to meet Geotracker requirements. <br /> 4.4 Well Development <br /> WeII development will be conducted no sooner that 48 hours following installation to allow for <br /> grout curing. -The wells will be developed using a combination of bailing, swabbing with a surge <br /> block, and pumping with a submersible pump. Well development will be performed until the well <br /> L is relatively.free of fines. Groundwater elevation measurements and groundwater samples will be <br /> collected no sooner than 48 hours following well development. <br /> 4.5 Equipment Decontamination <br /> The following subsections describe the methods to be followed for decontamination of drilling <br /> L and sampling equipment. <br /> L <br /> 4.5.1 Drilling Equipment <br /> Drilling equipment,including augers and tools,.and other equipment that may come in contact <br /> with potentially impacted soils or water will be steam cleaned prior to well construction. <br /> L4.5.2 Sampling and Testing Equipment <br /> Prior to and'after use, sampling and testing equipment will be washed in a non-phosphate <br /> t (Alconox)solution,rinsed with potable water, and rinsed again with distilled water. Hard-bristle <br /> brushes may be used in the first two wash buckets to remove mud and debris. Potable water will <br /> be obtained(from on-site sources. Distilled water will consist of 5-gallon containers from a <br /> commercial.supplier. <br /> 4.5.3 Submersible Pumps <br /> } The exterior of submersible pumps and hose used to purge wells prior to sampling a well will be <br /> brushed with an Alconox solution, steam cleaned using potable water, and rinsed with distilled <br /> water. As a;finai step,the interior of the pump and hose will be rinsed by purging with 5 gallons <br /> of distilled water. <br /> 4.5.4 Personnel Decontamination <br /> Site personnel will follow the personnel decontamination procedures to be outlined in the project <br /> L HSP. <br /> 4.6 lnvestigation-Derived Wastes <br /> Wastes expected to be generated during this investigation include drill cuttings,monitoring well <br /> purge water, and decontamination rinsate generated during the site assessment activities. <br /> ij <br /> 4 <br /> j <br />