A Call for New Directions in Drilling and Sampling Monitoring Wellsby Joseph F. Keely, Oregon Graduate Cent, Beaverton, OR, USA,
Kwasi Boateng, Oregon Graduate Cent, Beaverton, OR, USA,
Abstract: The hollow-stem auger drilling technique has an inherent limitation of disturbing large volumes of subsurface materials around the borehole, thereby possibly affecting local permeabilities and creating annular channels for the movement of contaminants into previously clean strata. At hazardous waste sites where hydrogeologic conditions are not well defined, or where a known or suspected contaminated aquifer is perched above an important aquifer, the hollow-stem augering technique may not be advisible. Air rotary and cabletool drilling use a temporary casing that shields one strata from another, and allows the emplacement of an adequate filter pack. Air rotary drilling may result in the emission of noxious vapors from the borehole when contaminated strata are encountered, however; and may result in undesirable invasions of the near-borehole environment when water is used. The recommendations given to date regarding sampling devices may not have adequately considered the performance of mechanically-driven positive-displacement devices. A limited field test indicates that more work should be done in this area. Such work may have implications for the treatment of data from private wells, that are often included in contaminant plume definition efforts.
Subject Headings: Cables | Wells (water) | Boring | Pollutants | Occupational safety | Waste sites | Aquifers
Services: Buy this book/Buy this article
Return to search