CORE SAMPLING

Geoprobe introduces a 3in version of its interlocking split spoon

A common challenge in Alaska, where the geology is glacial till and large cobbles, is frozen ground, but that has proven to be no deterrent for the Geoprobe 2in interlocking split spoon. In fact, Discovery Drilling found the split spoons to be “vastly superior to the legacy samplers for sampling frozen ground”.

 A Geoprobe split spoon just pulled from a job site after being driven to refusal on bedrock (30 to 50 blows with the 340lb auto drop hammer) in two, 35ft borings

A Geoprobe split spoon just pulled from a job site after being driven to refusal on bedrock (30 to 50 blows with the 340lb auto drop hammer) in two, 35ft borings

"It's what goes on above ground that really matters. Any split spoon can be driven into the subsurface to collect a sample, but it's the ease of use that separates Geoprobe's interlocking split spoons from ‘Brand-X'," said DJ Wardwell, operations manager Discovery Drilling.

"The interlocking splits, combined with the excellent thread pattern on the shoe and drive head, make it just so easy to assemble and disassemble. That ease of use is where the real value of these new samplers lies, and like anything Geoprobe makes, they can handle the intense stress that we routinely put on them."

After just a few uses of the 2in interlocking split spoon, Discovery was convinced they needed the new design in a 3in version to satisfy their sample hungry clients. In their market, 80 per cent or more of the geotechnical jobs - where split spoon sampling and blow counts are required - are conducted by advancing a 3in split spoon with a 340lb. drop hammer. With this customer feedback in hand, Geoprobe tooling engineers set out to meet their need and then let Discovery put them to the test.

"We've conducted several projects so far with the new 3in spoons… We've sampled geology where the spoons would have to endure 100 blows with the 340lb. hammer to barely achieve 6in of penetration, and they come out of the ground still maintaining their integrity," Wardwell noted. "And most importantly, they are hardy enough where even after that kind of punishment, they still assemble and disassemble vastly easier than the legacy samplers we were used to."

"We've yet to damage a set of splits, and on the traditional ones those usually are the first to go," Keeter Brown, Discovery Drilling partner, said. "We used to have to buy a ton of the legacy style, but these are a total game-changer."

Depending on the type of work, Discovery clients often choose to open and close the split spoons themselves to assist with production. On a recent job, upon opening her first interlocking split spoon, a geologist Wardwell works with exclaimed, "my wrists want to know where you have been all my life."

"We've received nothing but positive feedback concerning the sampler's robust and economical design. It just works, and really well," said Wardwell. "We've had a couple instances of clients specifically requesting - demanding even - that we bring the new interlocking spoons, as they are so much easier to manage in the field."

While Discovery has not yet sampled permafrost with the new 3in interlocking split spoon, they expect the results to match those of the 2in version - because it is Geoprobe.

Built for efficiency, the Geoprobe interlocking split spoon's multi-lead threads mean fewer turns to assemble while finger-like design self-aligns spoon, making it faster in the field. This design also means sheath stays aligned during impact, eliminating bulging and bowing. Design and enhanced material strengthen the entire sheath, increasing longevity. Available in 2 and 3in versions.

Got a story? Email: duncan.moore@aspermontmedia.com