Exploration Drilling Rigs Also Succeed Dewatering Mining Sites

For years, Nutrien — the world’s largest fertilizer producer— used “army-style” exploration drilling rigs on their White Springs, Florida, phosphate mine to do geological exploration. Around 2009, they suspended in-house drilling, opting to subcontract services. Until 2023.

“We needed to find ways to expand the life of the mine, which we were doing at a much slower pace, and more of a data gap analysis to shore up the model while sub contracting,” John Pazel, senior geologist, said. “With the DM250, we can have the rig out on the highway better to look at off-site projects to add to the mine.”

Choosing exploration drilling rigs to reinstate in-house drilling began by identifying manufacturers who offered local service support.

“With the service center in Ocala, we felt confident we would have service support, so we began evaluating different models and relying on the sales team to guide us from there,” Pazel said.

With the DM250, they found a drill rig solution which can easily maneuver through the tough terrain.

“When mining begins, the area is clear cut. So it’s either dry and dusty, or wet and muddy,” Pazel said. “Without altering how it was when delivered, the dual-tire rear axle is powerful even with the weight.”

He appreciates the ability to get into areas thanks to the compact size and an improved turning radius compared to their older “army-style” exploration drilling rigs. They’re also grateful for the enhanced safety features.

“You can tell the engineers paid detailed attention to safety,” Pazel said. “The rig does a lot of rod handling for you. It’s also quiet and really good on the decibels.”

They typically identify coordinates for drilling in office using AutoCAD. They use GPS and stake out boring locations, generally sampling in a 330-foot grid. Using a 4.5-inch OD barrel with a core bit containing two rows of carbide-tipped teeth, they rotate the 10-foot long barrel down into the subsurface. They place the retrieved samples into core bags to evaluate the structure of the sands and sediment layers.

“The drilling team bores until they hit hard lime rock. They can feel the difference between the phosphate matrix and the lime rock,” Pazel said. “We use a conventional barrel with a two-way ball valve responding to water pressure, which plugs the sample in when tripping out. It can be anywhere between 25- to 70-feet deep, and the DM250 handles it all just fine.”

To manage runoff and dewatering mining sites, they run ditches around the field and install recovery wells to release water into the ditches.

“The DM250 is better for installing dewatering wells,” Pazel said. “It quickly puts a borehole in the ground to install the dewatering well.”

With the DM250, they’ve found the multi-purpose rig to do everything their old “army-style, overstock” exploration drilling rigs did, but with a complete team behind them to provide support.

“Since we made the purchase, we can drill many more holes per year to expand our exploration while also installing air release dewatering wells,” Pazel said. “Basically, we can get both done for the price of one. We’re at cruising altitude now.”

DM250 Options

Water Transfer and Centrifugal Trash Pump 
Provides ability to pump out mud pit or prime centrifugal mud pump. Can be used to drill when in a bind, or refill water truck from the developing well.

On-Board Desander Cone 
Utilize rig hydraulics rather than separate power source to separate solids during fast drilling.