Xcel Energy Inc. said Tuesday that a major overhaul of its Prairie Island nuclear power plant in Red Wing, Minn., is moving forward without interruption despite the partial shutdown of the federal agency that oversees reactor safety.

Workers are undertaking a long-planned $280 million replacement of two steam generators on Unit 2. The reactor's core has been emptied of radioactive fuel, which is being temporarily stored in a water-filled pool inside the containment building.

Jim Lynch, Xcel's vice president for the plant, said in an interview that the two old steam generators have been cut in half in order to fit through a portal in the building, and three of the four pieces have been taken out, with the final piece to be removed Wednesday.

Inspectors not furloughed

He said the work is being overseen by the two resident inspectors from the Nuclear Regulatory Commission who were among the 300 agency employees not furloughed last week. He said regional NRC inspectors whose job was to assess the replacement work plan had already completed their review before the agency sent home most of its 3,900-member staff as a result of the partial shutdown of the federal government.

Proceeding on schedule

"We are just proceeding on the originally defined schedule," Lynch said of the project.

The next stage of work, including welding new equipment to the existing reactor, would have been inspected by the still-working onsite NRC inspectors who spend every day at the plant, he said.

"We X-ray every single one of the welds and document the quality of the welds," Lynch said. "It is checked by our onsite line management, it is checked by our independent quality assurance. … They [the X-rays] are available for inspection and will be inspected by the NRC after we have completed the job, and by the on-site folks."

Concerns from community

Despite those assurances, the plant's nearest neighbor, the Prairie Island Indian Community, has raised concern that the NRC is allowing the plant to open an access door of its containment building to move equipment at a time when the regulatory agency is short-staffed.

"Once you open up the containment building, there is a potential for release," said Tribal Secretary Ron Johnson in an interview.

The NRC's partial shutdown also postponed two of that agency's regulatory reviews of waste storage issues — delays also criticized by the tribe, which has long challenged the storage of spent radioactive fuel rods in casks on the reactor property.

Lynch said it's not uncommon for reactors to operate with no NRC staff on-site. The plant's resident inspectors usually work day shifts, he said.

"People think that somehow if we are not watched, we won't follow the rules," he said. "We operate the plant 16 hours a day with the NRC not there."

David Shaffer • 612-673-7090 Twitter: @ShafferStrib