The Honeywell plant will not be processing fuel during the probe, which focuses on the fact that there have been four leaks since September.
By C.D. Bradley firstname.lastname@example.org
Company spokesman Mark McPhee said all scheduled workers reported to the plant Tuesday and were expected to continue doing so as the investigation continued.
A five-member Augmented Inspection Team sent by the U.S. Nuclear Regulatory Commission arrived at the plant Tuesday. The team is formed "to review the circumstances surrounding more significant events at NRC-licensed facilities," according to the agency.
NRC spokesman Ken Clark said the agency doesn't believe Monday's leak caused a substantial public health risk; rather, the team's presence reflects the fact that Monday's was the fourth leak since September even though the others were confined to the plant.
"The primary concern in this case lies more with the possible exposure to chemicals than to radioactive material," Clark said. He said of four area residents taken to Massac Memorial Hospital on Monday, three were treated and released, and a fourth was kept overnight as a precaution. No further details about those hospitalized were available.
Clark and McPhee said the review would culminate with a public meeting outlining the investigation's findings, possibly as soon as next week. The meeting will probably be held before the plant resumes UF6 production.
The plant delivers UF6 to facilities worldwide that enrich it in preparation for use in nuclear power production, McPhee said. One of those facilities has been the Paducah Gaseous Diffusion Plant, but Honeywell hasn't delivered UF6 there for several months, he said.
The NRC also sent a letter to Honeywell to confirm that UF6 operations were shut down, that the company initiated its own investigation, and that it will discuss both the results of the investigation and possible fixes with the NRC before resuming production.
The letter does not restrict the NRC from taking additional steps. An earlier review of three leaks in September determined that the company had taken sufficient corrective action.
McPhee said that some of the employees involved in UF6 production, which he estimated represented 80 percent of the plant's business, are involved in the investigation and that some were reviewing plant procedures. Others are performing non-production tasks, such as cleaning the plant, he said.
McPhee said Monday's leak — which came from a valve in the feeds material building, the largest structure in the complex — was not related to the September leaks, which don't appear to be related to one another.