A piece of the nuclear world lurks in oilfields, and it has reared its unwanted head in the Williston Basin of North Dakota, with reports continuing of illegally dumped oilfield byproducts from the Bakken Shale that contain naturally occurring radioactive waste.

The latest incident may be the state’s biggest dumping of radioactive oil filter socks, which are use to strain liquids during oil production, according to state officials. In North Dakota, this material usually is trucked in sealed vehicles to other states, such as Colorado and Montana, that are able to handle the materials, which North Dakota is unable to do.

The material is designated as technically enhanced naturally occurring radioactive material (TENORM) waste. The North Dakota Department of Health (NDDH) is expected to issue regulations in June that would track generation, storage, transportation and disposal.

NDDH is handling the cleanup and response to the latest incident. “Current state law and administrative rules require that all TENORM waste be disposed of appropriately and violations can result in fines,” said spokesman Scott Radig.

A spokeswoman for the state Department of Mineral Resources (DMR) that oversees oil and gas operations said the agency is aware of the recent incident and it is working with the health department to determine the best ways to combat illegal dumping.

“It is a difficult issue right now because we don’t have proper disposal site in North Dakota, so it [the TENORM] has to be trucked out of state,” said Alison Ritter. “For the most part, the majority of the state’s operators are doing this right. There is a small minority doing it inappropriately.”

The onus now falls on the NDDH to enforce rules in the oilfields.

“There is a level of radioactivity that is above 5 pico periods/gram [of radium] that is not allowed to be disposed of in North Dakota,” Ritter said.