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of bentonite pellets was placed on top of the sand, and wetted with water The top of the bentonite was located at 30 ' bgl with a weighted tape The casing was cut off slightly below ground level and covered with a metal plate to prevent entry of surface materials Refer to PLATE IX for details of the well completion 1 Soil samples were taken at 5 ' intervals from 15 ' bgl to 50 ' bgl in soil boring "D" (MW-4 ; ) refer to PLATE V for details of recovery, blow counts, lithology, etc . After retrieving the last core, the augers were advanced to 55 ' bgl , and casing was run and sand-packed as described above . Refer to PLATE VIII for details ' of the well completion After completion of Monitoring well #5, and cleaning the augers & core barrels, the rig was repositioned on the location marked for t soil boring "B" (PLATE III, ) which was adjacent to the site of the removed dispensing pumps Drilling began at about 1300 hours, and the first core was taken from 101 -1116" . The core was handled, described, screened, and preserved using field proce- dures given earlier Additional cores were taken at 5 ' intervals from 15 ' bgl to 50 ' bgl , refer to PLATE IV for details Obvious petroleum contamination was noted in all cores from 15 ' to 511611 , with PID readings in excess of 2 , 000 ppm in core material from 25 ' bgl to 4616" The augers were advanced to 55 ' bgl , but no additional cores were taken . Since this soil boring was not to be converted to a monitoring well, it was grouted with a cement/ bentonite mixture from bottom to the surface by use of a flexible hose ' After completion of MW-4, the rig was repositioned on the spot marked for soil boring "A" (MW-6) as shown on PLATE III . Drilling began at 1400 hours, and the first core was taken from ' 251 -2616" It was handled by field procedures described earlier. Additional cores were taken at 5 ' intervals from 30 , bgl to 4616" bgl ; refer to PLATE VII for details Augers were advanced to 55 ' bgl for completion 2" OD Schedule 40 blank and slotted casing was landed at 551 ; 020" slotted screen extended from 55 ' to 35 ' bgl, with blank casing to the surface. The well was sand-packed and completed in the same manner as the other 2 ; details are ' given on PLATE X. After grouting soil boring "B" , the three wells were grouted from the bentonite seals to the surface with cement slurry displaced with a flexible hose . Each well was fitted with a preformed vault which was thoroughly cemented in place; casings extended approximately 6" into the vault, and were fitted with expandable locking seals . Each vault was covered with a traffic ' cover to prevent damage Containerized drill spoils were stored on site pending appropriate disposal 1 6