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� threaded, schedule 40 PVC. Based on previous experience in the area, a 0.020 inch slot size will be used. Placement of the screen has been determined based on the geology observed at the time of the drilling of the soil boring, as previously discussed. A flush threaded schedule 40 PVC screw cap will be used to cap the bottom of the well. All soil •brought:to;.tho.::surfaca�by,auger. flightsz'w be ,dispsrsed:.;on-the;eurface at;; thesite iw=, Well construction will be completed using washed, kilned and bagged Monterey #3 silica sand for the filter pack. The sand will be tremied into place around the well screen to a he .ght of three feet above the top of the well screen. A minimum one foot thick bentonite seal will be placed above the sand pack using 0.5 inch manufactured bentonite pellets poured into place through the augers. The well annulus will then be sealed to the surface with a 5% (dry weight) bentonite/cement grout, pumped into place from the bottom up via a tremie line to approximately three-feet BGS. The well completion will consist of a protective christy box set flush into the asphalt, provided such a design is not in conflict with the property owner's requirements. Inside the protective christy box, the four itch PVC well casing will be capped with a four inch schedule 40 PVC slip cap. The well will be developed by a combination of swabbing and bailing. Development will continue until the well discharge water is sediment free or until a total of two Hours of development time has elapsed.' During well developmen•e, the tctal purge voluma will be computed and recorded in the field log book. Following _. development, the well wi13 remain ;.ale for at least three days prior to sampling. All augers, bits, down-hole tools, the well casing and screen and development tools (swab, bailer and pump) will be steam cleaned prior to first use. 7.3 Water Sample Collection Fallowing completion of the monitoring well installation and development, groundwater sampling will be conducted. At the time of water sampling, the depth to water will be measured and the total well depth will be verified. Using these measurement, the volume of standing water in the well and the required purge volume will be calculated and recorded on a standardized well sampling lcg sheet. Prior to purring, a clear teflon bailer will be used to collect a standing water sample. This sample will be visually inspected : or floating product. The presence or lack of floating product will be noted. This standing water sample will then be collected to represent the total petroleum hydrocarbon analytical sample. The well will thea be purged by being bailed or with a ---_- -three- inch-submersible_ pump---prior--to--collection of--the -water- - -- -- --- - samples. The pump will be thoroughly cleaned prior to use with a high pressure potable water spray rinse. At the beginning of the well purge, -the pH, temperature and specific conductivity of the water will be measured and -recorded. These parameters will be rechecked an a regular basis and purging will be considered