Geoprobe® brand Dual Tube Sampling Systems are efficient methods of collecting continuous soil cores with the added benefit of a cased hole. Our line of Dual Tube Soil Sampling Systems drill rods include: DT22, DT325, DT35, DT37, DT45, and DT60.
Dual tube sampling uses two sets of probe rods to collect continuous soil cores. One set of drill rods is driven into the ground as an outer casing. These drill rods receive the driving force from the hammer and provide a sealed hole from which soil samples may be recovered without the threat of cross contamination.
The second, smaller set of probe rods are placed inside the outer casing. The smaller drill rods hold a sample liner in place as the outer casing is driven one sampling interval. The small drill rods are then retracted to retrieve the filled liner. Expendable cutting shoes are used when performing multiple tasks in the borehole such as monitoring well, soil vapor and sparge installations.