Air sampling indicates the likelihood of exposure on Dec. 22 to the plant's neighbors was minimal to none.
By Joe Walker email@example.com
"We do have results back for our employees, and basically they came back all clear," said plant manager Rory O'Kane. "We don't know about public urinalyses yet, but air sampling tells us the likelihood of exposure to the public was minimal to none."
The company and Nuclear Regulatory Commission are investigating the release and three other apparently unrelated chemical leaks in September. NRC officials tentatively plan to discuss their findings in a public meeting Jan. 6, but a time and place have not been picked, said NRC spokesman Roger Hannah.
Honeywell converts natural uranium to uranium hexafluoride, or UF6, for use in nuclear fuel. Although UF6 is mildly radioactive, it is mainly a chemical threat because it emits toxic hydrogen fluoride, or HF, when exposed to moisture in the air, the NRC says.
Production ceased after the Dec. 22 release, and the shutdown will continue "until the NRC and Honeywell are jointly satisfied it's safe to operate the plant," O'Kane said. All 315 employees are still at work — some helping with the investigation, some reviewing procedures and others doing nonproduction tasks such as cleaning.
There are no plans for layoffs. The company in fact is hiring 30 more workers amid expanded business at the Metropolis plant, the nation's only converter of uranium to UF6, O'Kane said.
Honeywell, which had traditionally sent all its UF6 to the Paducah Gaseous Diffusion Plant, last year began exclusively supplying USEC competitors in Europe. Honeywell still does business "on paper" with USEC, but the UF6 goes to Europe in what is essentially an international swap of material by governments, he said. USEC gets UF6 from Russia in a nuclear disarmament deal.
The Dec. 22 release began at 2:24 a.m. in a process building and made its way outside, resulting in the evacuation of more than 20 people residing less than a mile from the plant. Four residents were hospitalized — two treated and released, and two held briefly for evaluation, according to the plant and NRC. About 75 people were told to stay in their homes as a precaution.
O'Kane said Honeywell is still evaluating the cause and quantity of the latest release, which lasted about an hour. The NRC said radioactivity outside the plant was within safe regulatory levels, but an investigative team was sent to the plant because the leak was the fourth since September. An earlier review of the three previous leaks determined that the company had taken sufficient corrective action.
O'Kane gave this account of the previous incidents:
On Sept. 9, an employee was "pretty seriously hurt" by accidentally inhaling a puff of HF from a vaporizer that converts liquid HF to gas. The employee returned to work after just over a month, including about two weeks' hospitalization for facial burns and HF inhalation. A tiny amount of the chemical escaped and was confined to a building.
On Sept. 12, about 18 pounds of antimony pentafluoride, a Honeywell specialty chemical, leaked from a building toward the Ohio River. Because no homes or businesses were affected, there was no evacuation or involvement from outside agencies, O'Kane said. He said the NRC was notified "as a courtesy," even though NRC doesn't regulate the nonradioactive chemical. As with UF6, the main threat of antimony pentafluoride is HF emission, O'Kane said.
On Sept. 30, about three grams of UF6 leaked and were confined to a building. The leak was stopped by operations personnel.