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PES Environmental,Inc. <br /> Ms. Emily Cushman <br /> November 4, 2016 <br /> Page 3 <br /> During well construction, the PVC well casing will be suspended to ensure vertical alignment <br /> and plumbness. The depth and proper placement of the annular materials will be measured and <br /> confirmed throughout the well installation process using a weighted tape or similar measuring <br /> device. The hollow-stem auger will be removed after/in conjunction with placement of the <br /> sand filter pack and borehole seal. <br /> A minimum 2-foot thick hydrated bentonite pellet seal will be placed above the filter packs of <br /> the wells. In accordance with applicable regulations, the annular space above the bentonite <br /> seals of the wells will be tremie sealed with a neat cement grout to a depth of approximately <br /> 2 feet bgs. The blank casing in all the wells will be extended to approximately 0.5-foot bgs, <br /> and an expansion well cap will be used to secure and seal the top of each well casing. <br /> Traffic-rated, flush-mount vaults will be installed in concrete over the well heads for <br /> protection. See Plate 3 for a typical well completion diagram. <br /> A State of California Well Completion Report for each well installation will be submitted as <br /> required. <br /> Monitoring Well Development Activities <br /> Following a minimum 72-hour period after placement of the sanitary seal, the monitoring <br /> wells will be developed using a combination of bailing, swabbing, and pumping with a <br /> submersible pump. The objective of well development is to remove fine-grained material <br /> inside the filter pack and casing, to stabilize and sort the filter pack around the well screen, <br /> and to produce representative water samples from the monitored zones. During well <br /> development activities water parameters including pH, temperature, conductivity, and turbidity <br /> will be monitored with field instruments. Well development will be continued until the <br /> discharge water is visually clear of sediment and the turbidity of the groundwater is less <br /> than 50 nephelometric turbidity units (NTUs), if feasible. <br /> Purged groundwater and rinsate generated during well development and decontamination <br /> activities will be temporarily stored in DOT-approved 55-gallon drums. <br /> Monitoring Well Surveying <br /> The top of the well casings will be surveyed by a California registered land surveyor, to obtain <br /> reference elevations relative to NAVD88 and horizontal and vertical coordinates at each <br /> monitoring well location relative to NAD83. <br /> 148400101woo5.d«X <br />