Nuclear Fuel Services president Joseph G. Henry has been named chief operating officer of the Babcock & Wilcox Y-12 plant in Oak Ridge.

Babcock & Wilcox is the government's primary contractor at the Y-12 nuclear weapons plant, where the military's store of weapons-grade uranium is kept.

Henry "is expected to temporarily serve in the COO position at B&W Y-12 for the next several months," according to a Y-12 National Security Complex news release.

NFS, in Erwin, is also a subsidiary of B&W. Henry became president of the NFS facility in January 2011, the fourth NFS president in recent years.

The COO position at B&W Y-12 is a new position created to assist President and General Manager Chuck Spencer "in overall site management with a particular focus on operations," the news release said.

Henry is a retired U.S. Navy rear admiral. Before coming to NFS, he worked at Y-12 as chief of nuclear safety operations.

Like NFS, Y-12 has had its share of operational difficulties, including a recent major security breach.

In the predawn hours of July 28, an 82-year-old nun and two other peace activists were able to cut through several security fences and reach the building that houses weapons-grade uranium, where they attached banners, spray-painted messages and dumped human blood.

The two men and the woman, Sister Megan Rice, were charged with federal crimes in connection with the incident, which caused an uproar among federal officials and a shakeup of top management at the plant.

Henry was also Y-12's liaison to the Defense Nuclear Facilities Safety Board, which will hold a field hearing in early October in Knoxville to gather more information on the safety of plant operations and plans for its Uranium Processing Facility.

At a hearing on Wednesday in Washington, members of Congress harshly criticized the U.S. Department of Energy for allowing the breach to occur.

NFS officials did not respond to questions about who would take over the top post at the Erwin facility, which manufactures nuclear fuel for U.S. Navy submarines and surface ships.

NFS is near the Nolichucky River, 28 miles upstream from Greeneville. The Nolichucky River serves as the primary water supply for the town of Greeneville.

While the position at Y-12 is described as temporary, there have been no formal indications Henry will return to NFS.

NFS has experienced numerous changes among the top management team in recent years.

Henry replaced David Amerine, who had served as NFS president from March 2010 until January. Amerine took the place of David Kudsin, who became NFS president in 2009.

"Joe's expertise and working knowledge of Y-12 is an asset to us, and we are fortunate to have him assisting us at this time.

"Ensuring safe, secure operations at Y-12 is imperative, and Joe brings a wealth of knowledge and experience to bear on our mission," Spencer said in a prepared statement.

Henry also emphasized safe operations during his time at NFS, which recently received a 25-year renewal of its operating license from the Nuclear Regulatory Commission.

Local environmental activist Park Overall said Wednesday that she is not surprised another NFS official has left the president position.

"NFS has been having some very serious management problems," she said.