A chemical waste landfill near the Columbia Gorge has been accepting hundreds of tons of radioactive fracking waste from North Dakota in violation of Oregon regulations.

Oregon Department of Energy officials issued a “notice of violation” to Chemical Waste Management’s landfill near the small town of Arlington on Thursday for accepting a total of 2 million pounds of Bakken oil field waste that was delivered by rail in 2016, 2017 and 2019.

With landfill officials’ permission, Oilfield Waste Logistics of Culbertson, Mont., dumped the waste, some of which registered radium at 300 times the state’s limits. On average, the waste registered radium at 140 picocuries per gram, according to Jeff Burright, a state nuclear waste remediation specialist. The state’s maximum level for waste stored at Arlington is 5 picocuries, he said.

Energy Department regulators said the landfill won’t be fined for accepting the radioactive waste because they believe landfill operators misunderstood state guidelines and weren’t aware of the violations, said Ken Niles, assistant director for nuclear safety.

He said the agency can only fine companies – ranging from $60 to $500 a day – under certain circumstances. Fines can be levied if a violator had previously been notified of a violation and repeated it or did something similar. The department also fines companies for willful violations or violations that result in “significant adverse impacts” to humans or the environment. Niles said none of those issues applied in the case of Chemical Waste Management.

“That could change if something were to change in our knowledge,” Niles said. “But the company has been taking this very seriously. They have been very cooperative and want to do the right thing.”

Regulators said they determined the biggest risks would be if the waste were ingested or inhaled, if people faced direct exposure or if it emitted radon. Currently, Burright said, the state does not believe those issues are a risk because of how the waste is stored on the 1,300-acre landfill, including being covered by at least 10 feet of other material.

Burright said that employees at the landfill avoided direct exposure because they work in pressurized cabins and when they’re outside, rely on oxygen masks.

Landfill operators did not respond to requests for more information made by phone and email around 5 p.m. Thursday.

The landfill, which has not accepted another load of Bakken oil field runoff since September 2019, must now create a risk assessment and action plan to address the violation. If the energy department receives enough feedback on the documents, Niles said, the agency could hold a public meeting to accept comments.

Dan Serres of Columbia Riverkeeper said his groups will be pushing for such a meeting and calling on state leaders to address how Oregon became “a fracking dumping ground.”

“The big question now is what happens to this waste that has been illegally dumped in Oregon? Do they have to clean up this mess they created by accepting this waste from North Dakota?” Serres said. “The level and scale of this infraction is alarming and galling.”

Regulators said landfill officials didn’t properly check state guidelines. Instead, Niles said, the landfill operators relied on their customer’s assurances that the level of radioactivity met state standards. After receiving a tip from a caller in North Dakota, Oregon regulators discovered the violation after checking data provided by the landfill as well as from the state of North Dakota.

Oilfield Waste Logistics, which touts on its website “We make compliance easy!”, “erroneously” cited Oregon rules and landfill operators referred to the wrong state standards for waste containing radium, regulators said.

“We don’t know if it was intentional or accidental,” Niles said, adding that the state nuclear waste rules are complicated. “They could have misunderstood.”

The state is considering whether to issue a notice of violation to the Montana company.

Oilfield Waste Logistics also did not respond to requests for comment Thursday evening.

Oregon regulators said it has become increasingly difficult to find places to dump fracking waste that comes from North Dakota, New Mexico and elsewhere. The Arlington landfill, which accepts about 20 million pounds of hazardous chemical waste a month, is among only a dozen sites nationwide that can accept certain types of such waste, they said.

Oregon doesn’t have any other locations that would accept it, regulators said, and several other states are seeking to enact limits on the waste similar to Oregon’s.

It’s unclear which route the waste took to come to Oregon. The energy department officials said they weren’t sure how it arrived in Arlington and added that the radioactivity levels did not require special warnings on train cars.

-- Laura Gunderson; lgunderson@oregonian.com; @lgunderson

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