Slurry wells considered for waste disposal in North Dakota
BISMARCK (AP) — A proposal to construct a pair of “slurry wells” in McKenzie County would offer a new option in North Dakota for disposing of oilfield waste, including radioactive material.
The project, proposed by Hydroil Solutions, involves building two wells north of Alexander that extend deep underground. Solid waste carried to the site would be combined with saltwater before the mixture is injected down the holes for permanent storage.
The Bismarck Tribune reports some believe such a facility could be the way of the future for handling oilfield waste that otherwise gets disposed of at landfills. Former McKenzie County planning and zoning director Jim Talbert said he was skeptical of the technology when he first heard about it, but the more he learned, the more he saw its promise.
“It looked to me like it was one based heavily in science and that it would protect the environment,” he said. “It was a way to eliminate landfills, eliminate saltwater and eliminate TENORM safely.”
TENORM refers to technologically enhanced naturally occurring radioactive material. The waste stems from soil, water and rocks that naturally contain low levels of radiation underground. When those materials are brought up to the earth’s surface during oil production, radiation can become concentrated in filter socks used to strain oilfield fluids, in sludge at the bottom of storage tanks and in scale that forms in well pipes, according to the state Department of Environmental Quality.
Not everyone’s sold on the proposed wells. Some people, including several residents of Tri Township, where the wells would be drilled, have concerns. That’s not uncommon for projects dealing with radioactive oilfield waste, particularly during the past few years as the state has grappled with creating rules and vetting proposals for facilities that would handle the material.
BJ and Wes Lindvig live just east of the proposed site. They’ve been trying to gather information about slurry wells and have a lot of questions about how the facility would operate. They worry about truck traffic and say there are already several waste facilities in their area, including a saltwater disposal well and a landfill, which a few years ago sought its own permits to bury radioactive waste. The township opposed the project, which never materialized.
“I’m not sure that we need another oilfield waste disposal site right in the same area,” BJ Lindvig said.
While no slurry well exists in the state, they have been used for decades in other parts of the country, such as in Louisiana and Alaska.
The concept first drew attention in North Dakota several years ago when Waste Management proposed constructing similar wells. A hearing for the project drew opposition from the county, and Talbert spoke out against it due to its proximity to an aquifer. The company later withdrew its application.
Talbert, however, is not opposed to the idea of a slurry well. He testified in favor of the Hydroil project at a state Oil and Gas Division hearing earlier this year.
Hydroil’s proposal is still in the permitting stage. It’s received several initial approvals from the state but will require more permits from the Oil and Gas Division, as well as a radioactive materials license from Environmental Quality.
Hydroil is a startup company with managers in North Dakota and Arizona that has contracted with Terralog Technologies to build the wells. Terralog, an Alberta, Canada-based company with experience drilling similar wells around the world, declined to comment for this story, citing a company policy against speaking to the media about clients’ projects.
“We are going to be the manager of the site overall, and Terralog will manage the process of injections,” Hydroil CEO Jacob Anderson said.
The slurry wells proposed for McKenzie County would handle three streams of oilfield waste.
In addition to TENORM, they would accept nonradioactive solid waste. State Mineral Resources Director Lynn Helms said that could include anything that normally goes into a landfill, such as contaminated soil, sludge and drill cuttings.
And like many injection sites in the Bakken, the slurry wells would dispose of saltwater that comes up alongside oil and gas at well sites. The fluid can render farmland infertile for decades if it spills.
Hydroil’s proposal is to grind up the radioactive and nonradioactive solid waste and mix it with saltwater to form a slurry, which would then be sent down the wells.
“It’s an absolute perfect solution to the whole TENORM problem,” Anderson said.
North Dakota has grappled with how to dispose of radioactive waste for years. At times, the materials have been dumped illegally.
New rules went into effect in 2016 letting landfills accept waste with a higher level of radiation than previously allowed, up to 50 picocuries per gram. But no facilities have managed to obtain permits to take that waste, although two landfills are currently in the application process.
Hydroil’s wells could handle even higher levels of radiation.
“We can put the hottest, nastiest stuff downhole,” Anderson said.
The slurry wells would not have to adhere to the 50-picocurie limit, as they are not landfills, according to Environmental Quality. They would have to comply with a radiation limit for possessing the materials above ground before they are injected. The cap would be based on the amount of financial assurance the company puts up, such as a bond, state environmental scientist David Stradinger said. The money guarantees funding will be available to clean up the facility if the company were to abandon it.
The department would also put monitoring requirements in place.