for week of March 6, 2006:
Hollow-stem auger (noun) The type of drilling rig that uses the auger drilling method to drill, with a hollow drill string through which soil samples can be collected and the well casing can be installed. The borehole is advanced in hollow-stem auger drilling by the removal of cuttings from the mechanical action of the auger flights on the drill string. Hollow-stem auger drilling is often used for the installation of shallow monitor wells, because it requires little or no drilling fluid.