The recent discovery that radioactive material had built up in a Columbia nuclear fuel factory has prompted federal warnings to other plants about the hazards of failing to properly monitor their facilities.
In a public notice issued this week, the U.S. Nuclear Regulatory Commission said accidents can occur when uranium is allowed to accumulate in fuel plants over time.
The agency urged other fuel factory operators to “consider actions, as appropriate, to avoid similar issues.’’ The NRC’s notice said the “long-term accumulation of uranium’’ has been a recurring issue in the nuclear fuel industry.
The notice went to about a half-dozen plants across the country, a day after the NRC held a public meeting in Columbia to discuss an investigation of the Westinghouse factory southeast of town.
“Other licensees need to know about this,’’ NRC spokesman Joey Ledford said.
At Tuesday’s meeting, NRC regional administrator Catherine Haney called the uranium buildup at Westinghouse a “serious event.’’ Top Westinghouse officials conceded the company had fallen down on the job in not properly keeping track of the uranium.
Over the summer, the NRC learned that uranium had accumulated in an air pollution control device, called a scrubber, to levels three times the federal safety standard. The agency and Westinghouse found other buildups inside the plant after looking more carefully.
Low-enriched uranium, like that used at Westinghouse, is not considered as dangerous as highly enriched uranium, but it can still be hazardous if not properly monitored.
When uranium accumulates to levels that exceed the safety standard, it increases chances of a “critical’’ event, a nuclear accident that can send out a burst of radiation. In the Westinghouse case, nearby workers could have been injured from the uranium buildup, agency officials said in a preliminary investigation report this past week.
Among the fuel factories notified of the Westinghouse problems were facilities near Wilmington, N.C. and Richland, Wash., both of which also make atomic fuel for commercial nuclear power plants.
A spokesman for the Wilmington-area plant said it has not had buildups of uranium above federal safety limits, but the facility’s owner was aware of the problems in Columbia and has taken steps to make sure similar problems do not occur in North Carolina.
“As soon as we learned about the events there, we conducted a self-assessment related to this specific area and found that all controls are working as expected,’’ Jon Allen, a spokesman for G.E. Hitachi Nuclear Energy, said in an email.
Westinghouse officials said this week they are taking steps to improve safety at the plant. The company has brought in new personnel, instituted new safety procedures and updated equipment to help, among other things.
While the company works to address the issue, it has shut down part of its production line and temporarily laid off more than 100 workers. The plant, between Congaree National Park and Interstate 77, employs about 1,000 people. Nuclear fuel assemblies are sold worldwide to power plants.
“Our leadership and workforce intend to earn back the trust and confidence of the NRC, the community and our customers,’’ company executive Michele DeWitt said.
The federal safety notice, issued Wednesday lays out new details in the unfolding Westinghouse story.
Westinghouse has had buildups of material in air pollution scrubbers since at least 2002, but the company did not accurately document how much uranium was in the material, according to the NRC. As a result, it is difficult to say whether Westinghouse exceeded safety limits in the past, an agency official said Friday.
The NRC information notice also said that for seven years prior to this year’s discovery of excessive uranium, the company did not thoroughly inspect and clean parts of the scrubber system. Some problems appear to have continued this year.
After Westinghouse analyzed the material from the scrubber, one division of the company learned that uranium levels exceeded the safety limit. But that division did not immediately share the information with the Westinghouse safety staff, said Omar Lopez, a NRC inspector who led the probe in Columbia.
“There was a break in communications between the operations group and the safety department,’’ he said.