Production Flies with DT325 Driven Casing Standard Penetration Testing (OTE)

A full-service environmental and remediation company, Geopro Inc, in New Jersey, conducts their own drilling. However, they also support a slate of clients through their probing, soil investigation, and monitoring well services. The past few years they’ve experienced growth in geotechnical work which they attribute to a surge in construction and to having team members willing to travel and do the tougher geotechnical jobs. Accustomed to running second-hand rigs, they rented a 7822DT for a job and were impressed by the multi-functional drill’s ability to conduct geotechnical work. 

“The power for the size is great,” Art Remedios, project manager, said. “We do a lot of light commercial and residential work and it fits on any of those sites. It fits the niche we fill.”

So when they decided to add a new rig to their fleet they gravitated to the 7822DT because of its versatility and footprint.

“We don’t need to mobilize more equipment. With the 7822DT you can quickly turn around and do something else required on a job site once you have tooling,” Remedios said. “We do a lot of preliminary investigations where there’s a backhoe creating a trail for us. The 7822DT’s size makes it a great off-road rig to run and do SPT in the woods.”

Driller Ryan Zajac describes the 7822DT as a probe modified to conduct geotech.

“For guys used to probing, it’s easier to teach them,” he said.

So when they landed a job conducting SPT sampling inside a beverage bottling facility, they leaned on their probing roots to meet the job requirements, investing in the 3.25 standard penetration testing (SPT) out-the-end (OTE) system. Remedios had seen the system on the Geoprobe^® website and during a demonstration day in Millstone, New Jersey, the previous fall.

“We needed to minimize dust and cuttings generated within the facility, so spinning augers was not an option. So once we had the project, I pulled the trigger on the 3.25 system,” Remedios said. “We conducted 10-15 geotech borings with almost no mess. The client was thrilled.”

A three-week job in Delaware required sampling a field designated for a 1.3 million square foot warehouse. Again they deployed the 3.25 standard penetration testing OTE system.

“Using the 3.25 OTE system was lighter to carry, productive, and easy to work with,” Zajac said. “The 3.25 rods are lighter to pick up than augers, so it’s easier on the guys doing long days of geotechnical sampling.” 

They completed 45, 40- to 50-foot borings with everything fitting within the rod rack. The clients were pleased with the continuous sampling along with the standard penetration testing. They also appreciated less mess on the site with the elimination of backfill or piles of dirt.

“Production is 30 to 40 percent faster than doing augers,” Remedios said. “Under the right soil conditions, you can fly with the 3.25 system.”

Remedios appreciates the support Geoprobe^® provides — both for his rig but also for tooling techniques.

“Last winter when we were looking at getting a rig, we bought the 7822DT because I knew I was able to call the guys in service and get back up and running if I ran into an issue. Others aren’t offering that level of service,” Remedios said. “If I have a tooling question, I can call Vic or one of the guys in the office to work through it.”

He also praises the tooling durability, attributing Geoprobe^® quality control measures.

“The actual probe rods over the years are more durable. The threads wear more slowly and are so much nicer. They are quick to thread, hold tight, and hold up,” Remedios said. “I think the edge Geoprobe^® has on other manufacturers is they actually test the equipment and tooling versus just doing it because everyone else is.”

DT325 Driven Casing Standard Penetration Testing (OTE) Efficiently Expands Market

Customers already using 3.25 tooling can expand their market and increase their efficiency doing out-the-end (OTE) SPT. The sampling system designed to work as one with the 3.25 rods includes the Geoprobe^® manufactured AWJ drill rods. 

Advantages of DT325 Driven Casing SPT (OTE):

• fast
• lightweight
• continuous sample
• no drilling fluid

Parts required to use your DT325 to do standard penetration testing:

• SPT OTE Centering Drive Cap
• 3.25-inch OTE Cutting Shoe
• DT325 Drive Head SPT Only
• DT37 Retainer Cutting Shoe OTE
• ADH Drive Cap Pin Down
• AWJ Drill Rod
• 2.0 Interlocking Split Spoon Sampler

It is best practice to consult applicable ASTM standards when performing geotechnical investigations.