A steady stream of naturally occurring but technologically enhanced radioactive wastes still heads across the Montana border for disposal at the Oaks Disposal site near Glendive.
That could change, however, if a pair of new slurry wells demonstrates a better, safer way to dispose of TENORM.
Lynn Helms is the director of the Department of Mineral Resources, which oversees the Division of Oil and Gas. He has been working with two companies to develop a new approach to these low-level radioactive wastes in North Dakota.
North Dakota Industrial Commission has recently approved the development of two slurry wells in northern McKenzie County, the first of their kind in the state. They will dispose of TENORM wastes by grinding them up into fine particulates and re-injecting them deep below the surface of the earth, back into the ground from which they came.
Naturally occurring radioactive materials are part of North Dakota’s shale layers, which also includes layers like the Bakken that house oil and gas. NORM comes up as solid wastes in varying amounts whenever crude oil and natural gas are extracted. It settles out into tank bottoms as a kind of sludge that must be removed before Bakken light sweet crude can be marketed.
Processing these wastes causes them to become “technologically enhanced.” Hence, the waste is referred to as TENORM.
“(Slurry wells) are not a brand new process or technology,” Helms said. “It is just new to the Bakken. Alaska has been doing this on the north slope with all of their solid waste for decades. You cannot have landfills in permafrost.”
The radioactivity of TENORM in general is very low, Helms said.
Despite that, however, disposal of the wastes has been controversial.
A few years ago, North Dakota eased its radiation limits to 50 pico-curies, to allow properly permitted landfills to accept the wastes. Permitting, however, appears to have stalled. I’ve inquired as to whether we have any permits, in fact, at all. I don’t think we do, but am still awaiting confirmation.
Helms said the slurry disposal well process has become more technical in how it’s managed.
“With the modern measurement and computer systems, they are able to manage the process much better, so we wrote this order to take advantage of that,” Helms said.
If the approach proves successful, it would be a safer way to dispose of the wastes than in landfills anyway, Helms said, and would reduce pressure on landfills.
“As (these wastes) decompose, they produce radon gas,” Helms said. “A lot of care has to be taken with the handling, processing and disposal of that. If this becomes commercial and widespread, it would be a much safer and more permanent way of disposing of that waste stream.”
The wells will be owned by Hydroil and operated by Terralog Technologies, which has done this kind of work in Alberta, Saskatchewan, California, Louisiana, Alaska, Indonesia, Saudi Arabia and Norway. Helms estimated the facility would be able to process 10 to 20 percent of the total volume of this kind of waste stream in North Dakota.
“That was one reason that the commission felt comfortable approving this is that these people have the experience all over the world and the know-how and qualifications to do it right,” Helms said.
The wells are not yet operating. The North Dakota Industrial Commission will be reviewing elevated bonding requirements for the two wells this month.
The usual bonding requirement for a disposal well is $50,000, but for these it will be $100,000. There will also be a third bond, yet to be determined, for the facility that will process the waste and prepare it for injection.
Helms said the state is being as cautious as possible about this new approach.
“We are starting with a much higher level of surveillance than what Terralog is used to,” Helms said. “Typically in states where they have been doing this a long time, they are doing monthly and annual reports. we are starting with weekly.”
The company will be required to collect the data it is providing on an hourly basis, too.
“We are starting out with everything we could learn from the Alaska and Louisiana rules and experience, with a very high level of surveillance, and go from there,” Helms said.
If everything goes well, then there could be more of the wells permitted in the state, perhaps six to 10 of the facilities, Helms estimated.
“This is definitely going to be a learning process for both of us,” he added. “Our intent is, if it moves beyond this application, that we will actually write a statewide rule based on what we learn here.”