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=. .. <br /> TM <br /> 7. Hollow-stern auger flights are 5-feet in length,therefore drilling i:. ternporariiy halted at 5-foot <br /> intervals so that additional auger flights can be attached. Auger [lights are attached to (Inc <br /> another by threaded ends and bolts. <br /> 8. As excavated soil accumulates at the top of the bore hole, it is shovelled into a wheelbarrow and <br /> moved out of the way. Since the excavated soil may be contaminated, it is placed on <br /> polyethylene sheeting to prevent any possible leaching of contanlinants. <br /> 9. If sampling or geatechl:ical cv:duation is to take place during drilling, advancement of the <br /> hollow-stem auger can he temporarily stopped and the soil plug, if present, can be removed. <br /> A device such as a split-barrel sampler or Shelby tube can be attached to the center rod and <br /> lowered to the bottom of the bore hole. Sampling or testing occurs in the undisturbed region <br /> of soil immediately beneath the deepest auger flight. <br /> 10. When the bore hole Inas been advanced to the depth desired, the center r(-,ds and soil plug, if <br /> present,can be removed,thereby allowing Wulf casing to be installed(sec SOPS 4100 and 4200 <br /> for various types of well installation). <br /> 11. If the bort:hole is not to be closed through procedures outlined in other SOPS, then it shall be <br /> closed by grouting with a cement/bentonite mixture (the local County Department of Health <br /> guidelines will be followed), <br /> 12. The grout is Added through the hollow-stem auger flights as the flights are removed. <br /> 13. Excavated material is temporarily covered by polyethylene sheeting or stored in 55-gallon drums <br /> on site for future disposal. <br /> 14. Upon removal of the auger flights and other downhole drilling equipment,all of the equipment <br /> should be decontaminated according to the procedures outlined in SOP 700E <br /> QA/QC: <br /> Quality control during drilling will mainly be the responsibility of the drill rig operator, and will be <br /> closely monitored by the DERS field geologist. <br /> REFERENCES: <br /> Driscoll, F.G., 1986. Groundwater and Wells.Johnson Filtration Systems Inc., St. Paul, MN, <br /> Written: 12-4-90 <br /> - <br />