A fire in equipment used to process radioactive material occurred on Saturday, Nov. 14, at the Nuclear Fuel Services, Inc. plant in Erwin, according to a report that did not appear until Thursday on the Nuclear Regulatory Commission's Web site.

NFS spokesman Lauri Turpin, when asked by The Greeneville Sun to comment on the incident, confirmed that a "small fire" had taken place last Saturday at the plant.

"It was contained within a sublimation station," she said.

Turpin said the sublimation station is the first point in a processing line used to down-blend uranium hexafluoride to a low-enriched state.

Sublimation stations, she said, are used to change uranium hexafluoride from the solid form in which it is stored in cylinders into a gaseous form for processing.

Turpin stressed that no radioactive material was released and that no workers were harmed as a result of the Nov. 14 fire inside the sublimation station.

She also said that NFS had been using the same procedure to process uranium hexafluoride since the NFS Commercial Development line went into operation in August and had never before had a problem.

The incident remains under investigation, according to Turpin, who said NFS officials don't believe the fire took place because of problems with NFS equipment.

It was possible, Turpin said, that the contents of the cylinder being processed could have been mislabeled.

She said the company's safety systems worked as designed and that the operators involved "acted appropriately" in keeping with their training.

But Barbara O'Neal, an Erwin resident who is a member of a group called the Erwin Citizens Awareness Network, said she believes the Nov. 14 incident "is indicative that they don't know what's in these cylinders."

O'Neal also said she feels the incident shows that an operational readiness review of the NFS Commercial Development line that was performed by the Nuclear Regulatory Commission was lacking.

The operational readiness review was performed prior to the granting of NRC permission to put the line into operation.

"I have no confidence in the operational readiness review," she said. "They should have foreseen that this could happen."

Trudy Wallack, a Greene County resident who lives along the Nolichucky River downstream from the NFS plant, also said she has questions about the NRC's regulation of the plant.

"Throughout the years," she said, "the NRC's position and message to the citizens is the same: 'Everything is fine' ...Yet, such events as this most recent fire support our concerns, and the ongoing history of incidents poses the same question: What is the resolution?"

"This event, once again, presents dreadful news. We challenge the Nuclear Regulatory Commission to regulate and ensure a sustainable and safe operation."

A "Current Event Notification Report" that was posted on the NRC's Web site on Thursday said a fire took place on Saturday, Nov. 14, in a "process glove box."

The report stated:

"On Saturday, Nov. 14, at approximately 7:30 a.m., there was a heated, high-pressure release from the 5A/5B UF6 [uranium hexafluoride] cylinder in the CDL [Commercial Development line] facility sublimation station 3."

"At the time of the upset [accident], the operators were in the process of preparing the cylinder for sublimation."

The report said the cylinder was not being heated at the time of the incident.

"The release occurred when the cylinder valve was opened ... to vent the cylinder to column 1D01," the report said.

"The release ruptured the connective Teflon tubing that was enclosed in braided stainless steel. When flames [were] observed, the operator actuated the carbon dioxide release valve and extinguished the flame."

The report said damage appeared to be limited to the Teflon tubing, a singed area on a Lexan cover of the enclosure, and a possible leak on the inlet and outlet side."

The report said there were "no actual exposures [to radioactive material] to the workers, the public and environment."

The report also said that although there was "potential UF6 exposure to workers, no loss of containment occurred."

All of the NFS plant's sublimation stations were taken out of service while an investigation is under way, the report noted.

NFS manufactures fuel for the U.S. Navy's fleet of nuclear-powered submarines and aircraft carriers and also down-blends highly-enriched uranium to a low-enriched from suitable for conversion into fuel for TVA power-generating nuclear reactors.

The plant recently implemented a process to convert highly-enriched uranium hexafluoride into a low-enriched form.