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Wider tracks on 3126GT geotech drilling rig make trekking over varying soil conditions easier.

Wider tracks on 3126GT geotech drilling rig make trekking over varying soil conditions easier.

Founded in 1985, Tri State Drilling LLC initially offered geotechnical engineering and construction materials testing services to their clients, including drilling services.

“In 2007 we sold the geotechnical engineering and construction materials testing piece of the business, which was a good move because it allowed us to focus on drilling,” Rob Bittel, president, said. “This also gave us opportunities to drill more for local firms who viewed us as competitors when we offered engineering and testing.”

Now they have 10 rigs operating on a daily basis providing environmental, geotechnical, and mineral exploration drilling services for engineering firms across the southeast from their offices in Chattanooga and Nashville, Tennessee. Three of their rigs are Geoprobe® ­— two 7822DTs and one 3126GT geotech drilling rig.

“We wanted to replace one of our oldest rigs and had been pleased with Geoprobe® products. Even though 3126GT was newer to market, we wanted to look at it,” Bittel said.

While talking with Lee Shaw, sales representative, he described the 7822DT as a direct push rig that can also do geotechnical drilling while the 3126GT is a geotech drilling rig that can also do direct push. Bittel also witnessed a demonstration of the 3126GT at their shop during one of Shaw's road trips. The performance and availability of the 3126GT convinced them to place their order shortly following the demonstration.

“Our operator is very pleased with the rig thus far, and he has already put it on some interesting projects, including a barge project over water, 200-foot rock coring at a quarry site, air rotary, and hollow stem auger from 2.25 to 6.25 inches,” Bittel said. “The rig has not backed down from anything we’ve asked it to do. I think it’s safe to say we will buy another one in the future.”

The rotation speed and overall rock coring capabilities surprised their driller who cores with it almost daily. They also appreciate how well the carrier tracks and the user-friendly setup of the rig.

“Stepping up to the 3126GT was a good decision for us. The 7822DT had limitations on depths, auger size, and other factors we had to consider before mobilization,” Bittel said. “You can tell Geoprobe® invests a lot of resources on R&D and relies on feedback from rig owners to assist them in making the best product they can.”

They have been pleased with overall performance of the 3126GT geotech drilling rig. They drilled a 250-foot core hole at a quarry site in East Tennessee where productivity and recovery were good. More recently they did some air rotary drilling with it.

“We are all in unprecedented times where companies are having to push the limits, if you will, due to workload, increase in cost of doing business, and labor shortage. Our operator of the 3126GT has met most if not all of our production goals since we bought the machine and he seems to enjoy coming to work more,” Bittel said.

Their service department is also happy with the support Geoprobe® provides.

“I can’t tell you how many times I’ve walked through the shop when our mechanics are working on a rig and Face Timing with a Geoprobe® technician troubleshooting a problem,” Bittel said. “That means a lot to us.”

For Bittel, the advantages of Geoprobe® rigs, including the 3126GT geotech drilling rig, are numerous — from being operator and maintenance friendly to their dependability and maneuverability.

“We are a better company with the 3126GT than we were before we bought the machine,” Bittel said. “Geoprobe® was listening to their customers when they designed that rig. The 3126GT checked all the boxes for Tri-State Drilling.”

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

Geoprobe® - 31 Series Overview

3126GT geotechnical drill features centerline head side shift

3126GT Geotechnical Drill Rig

Save time and effort swiftly sliding the innovative centerline head side shift into position for rotary, automatic drop hammer, even CPT or direct push. No need to move the geotechnical drill or drill mast on the compact, off road drill rig.

Photo Gallery


Wider tracks on 3126GT geotech drilling rig make trekking over varying soil conditions easier.
Separate hydraulic circuit for mud pump on 3126GT creates consistent power for both pump and rock coring drill rotation
3126GT sneaks into small spaces with power to conduct geotechnical sampling.
Small footprint with ample power makes 3126GT geotech drilling rig suited for barge project over water.

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