Skip to main content
DT325 OTE Driven Casing SPT standard penetration test procedure

DT325 OTE Driven Casing SPT standard penetration test procedure

Out-the-end (OTE) SPT has gained favor with drillers and engineers. The ability to collect continuous soil samples more quickly — pushing the casing versus completing traditional geotechnical drive and wash — has created business advantages for companies utilizing the OTE standard penetration test procedure.

"Under certain soil conditions it (OTE and dual tube) can be twice as fast as drive and wash," said John Clark, general manager SAGE Envirotech Drilling Services. "Twice as much data. Twice as many borings. Twice as much vertical feet in a day, putting us on par with traditional auger rigs and then some."

For SAGE Envirotech in Rhode Island, they were able to complete nearly a year's worth of work in a week, gaining them additional work from very pleased new clients. Similarly, Platform Environmental Drilling and Remediation in Vermont impressed a very particular engineer with the ease and effectiveness of OTE standard penetration test procedure.

"He was shocked by how fast we got downhole and how we retrieved a continous sample from the deeper portion, getting reading inbetween where we would typically be doing split spoon samples," Michael Jordan, owner, said.

Recognizing a preponderance of customers already use 3.25 tooling, Geoprobe® looked to help them expand their market and increase their efficiency doing OTE SPT.

"We're opening the door to those folks to do SPT with just the addition of a few parts to their 3.25 tooling lineup," Kyle Reidel, tools group manager, said. 

The sampling system designed to work as one with the 3.25 rods includes the NEW Geoprobe® manufactured AWJ drill rods (see below). 

Much lighterweight when compared to 3.75, the tooling system collects quality samples much more quickly when compared to using the 375 OTE system. The tooling system also works better under a smaller class hammer.

"We've tested the system and it works great," Reidel said. "During our testing, comparatively there was less tendency to overfill the sample. We're excited to hear whether customers have the same experience."

Advantages of DT325 OTE Driven Casing SPT standard penetration test procedure:

  • lightweight
  • fast
  • provides a continuous sample
  • does not require drilling fluid

Contact Us

1835 Wall Street
Salina, Kansas 67401
Phone: (785) 825-1842

DT325 Driven Casing SPT (OTE) Overview