North American Coal’s Falkirk Mining Co. has used a specially outfitted drone for nearly a year to plan for water management, compute elevation and help determine where topsoil and subsoil should be removed and stored. It’s also used during post-mining reclamation.
Greg Obrigewitch, a land surveyor, is part of the mine’s technical team that developed the use of drones after securing federal permission.
He said uneven terrain causes time-consuming and sometimes hazardous conditions for surveyors who had been on foot or in trucks.
“Drones provide an innovative way to retrieve topographical maps of large areas with minimal wear and tear on equipment and workers,” Obrigewitch said.
The mine’s fixed-wing Trimble UX5 was outfitted with an onboard global positioning system to take three-dimensional images for measuring true distances.
Obrigewitch said the drone is attached to a bungee cord system during takeoff and the electric propeller is started only after the drone reaches 35 mph.
It travels 50 mph in a pre-set flight pattern, taking photographs every 80 feet from a height of 250 to 400 feet. The data is downloaded to a computer for use in a few hours.
A downside is that drones are not accurate over vegetation, or water.
“It can be a perfect tool for the North Dakota mining industry because much of the area is without vegetation during the mining process,” Obrigewitch said.
Pending rules will allow drones to be operated by an operator, without requiring an additional observer. Obrigewitch said the mine plans to purchase a second drone that will have the ability to inspect equipment by hovering and maneuvering in tight spots.
The mine provides coal for the Great River Energy Coal Creek Stations near Underwood and Spiritwood Station at Jamestown.
