Dual Tube Soil Sampling Systems

Geoprobe^® brand Dual Tube Sampling Systems are efficient methods of collecting continuous soil cores with the added benefit of casing in drilling. Our line of Dual Tube Soil Sampling Systems probe rods include: DT22, DT325, DT37, DT45, and DT60.

Casing in Drilling

Dual tube sampling uses two sets of probe rods to collect continuous soil cores while also performing casing in drilling. One set of probe rods is driven into the ground as an outer casing. These probe 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 rods hold a sample liner in place as the outer casing is driven one sampling interval. The small probe 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.

Key Features

Continuous soil coring for faster sampling in intervals over 20-feet.
Continuous soil coring in both saturated and unsaturated zones.
Casing in drilling eliminates cross contamination.
Optional solid drive tip seals system for driving to top of sampling interval or for split interval sampling.
Perform bottom-up pressure grouting while retracting outer casing.
Install groundwater monitoring wells through outer casing after collection of soil core.
Set soil vapor implant wells after soil collection.