Discarding an oil filter sock, one of those nets that strain liquids during the oil production process, is not as easy as hauling it to the nearest landfill. Since they often end up contaminated with naturally occurring radiation they need to go to an approved waste facility – not an abandoned building.
That is just where North Dakota state officials found the biggest incident of illegal dumping of radioactive oil filter socks. State Waste Management Director Scott Radig said they found hundreds of the tubular filters last week in an abandoned building in Noonan, a town of about 200 people in northwestern North Dakota.
Radig, who viewed pictures of the scene, said it’s likely to be more than twice as large as the state’s next-largest dumping incident found last month in McKenzie County.
“It appears, unfortunately, to be the biggest one we’ve found,” Radig said. “And it appears to have been there for quite some time.”
North Dakota banned the disposal of filter socks, which can end up contaminated with naturally occurring radiation. Oil companies need to haul them to approved waste facilities in other states such as Montana, Colorado and Idaho, which allow a higher level of radioactivity in their landfills.
State regulators and law enforcement officials are investigating, Radig said. He said the filter socks found in Noonan showed low levels of radioactivity after testing.
“The public is not at risk as long as people don’t break into the building and start handling them,” Radig said.
Health officials said since the state’s oil production has soared in the past several years, they are finding radioactive filter socks increasingly along roadsides, in abandoned buildings or in commercial trash bins of an unsuspecting business — sometimes that of a competing oil company.
Divide County Chief Sheriff’s Deputy Rob Melby said there were “piles and piles” of filter socks scattered through a 4,000-square-foot building that once housed an auto shop.
“They’re piled up waist deep or higher,” he said. “There’s a lot of stuff in there.”
Deputy Zach Schroeder said he counted more than 200 trash bags of 55 gallons each filled with the filter socks.
Schroeder said authorities don’t know who left the filters in the building.
The state Health Department, in response to the growing number of illegally tossed filter socks, said last week that new rules are coming out to track oil field waste. A draft of the new rules should be ready for public review in June.