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Well Installation Report Project No. 507.2 July 3,2014 Injection Wells IW-5 thru 1W-11 Injection wells LW-5 thru 1W-11 were constructed using 6.0-inch diameter PVC casing with flush threads. The screen intervals extended from 15 to 25 feet below ground surface (bgs). A self compacting medium aquarium sand or gravel filter pack surrounds and extends two feet above the 0.020 inch screen interval. A granular bentonite transition seal was installed to a depth of three (3) feet above the top of the filter pack. A surface seal of neat cement grout was installed via a tremie pipe. The wells were secured with locking watertight caps and encased in flush mounted traffic rated well boxes. The table below shows the construction of IW-5 thru 1W-11. Well Dia./TD Screen Slot Sand Pack Trans. Seal Grout Seal 1W-5 6"/25.0' 15-25' 0.020" Med. Aquarium 13-25' 10-13' 10'-surface IW-6 6 /25.0 ' 15-25' 0.020" Med. Aquarium 13-25' 10-13' 10'-surface IW-7 6"/24.0' 14-24' 0.020" Med. Aquarium 13-25' 10-13' 10'-surface IW-8 6"/25.0' 15-25' 0.020" Pea Gravel 13-25' 10-13' 10'-surface IW-9 6"/23.0' 13-23' 0.020" Pea Gravel 10.5-25' 8-10.5' 8'-suiface 1W-10 6"/25.0' 15-25' 0.020" Pea Gravel 13-25' 10-13' 10'-surface 1W-11 6"/25.0' 15-25' 0.020" Pea Gravel 13-25' 10-13' 10'-surface Borehole logs from 1W-5 through 1W-11 are shown in Appendix E. 2.2. Well Development On February 19, 2014, GZA and V&W Drilling personnel mobilized to the site and developed three injection wells (1W-5 thru IW-7) using mechanical surging, pumping and flushing methods. The development process was continued until a clear stream of water was obtained. 360 gallons were removed from injection well 1W-5 over a period of 70 minutes. IW- 5 has a good recharge rate and did not dewater during development. 220 gallons were removed from injection well IW-6 over a period of 95 minutes. LW- 6 has a moderate recharge rate. 110 gallons were removed from injection well IW-7 over a period of 120 minutes. IW-7 has a poor recharge rate and continually dewatered during development. On March 31, 2014, GZA and V&W Drilling personnel mobilized to the site and developed four injection wells (IW-8 thru 1W-11) using mechanical surging, pumping and flushing methods. The development process was continued until a clear stream of water was obtained. 175 gallons were removed from injection well IW-8 over a period of 65 minutes. IW- 8 has moderate recharge. 65 gallons were removed from injection well rw-9 over a period of 202 minutes. IW- 9 has a very poor recharge rate and is suspected to be due to the well construction. Bailing methods were used to purge the well, however the well continually de- watered. Ground Zero Analysis, Inc.