The Diedrich Drill D-90
is a heavy-duty drill rig for soil and rock exploration for both
geotechnical and environmental investigations using augers or core
drilling tools. The D-90 is rated to depths of 150 feet(46m) to 300
feet(92m) with hollow stem or continuous flight augers up to 19
in(483mm) hole size. It is rated to 1500 linear feet(458m) of core
drilling using NW series tools.