The Energy Department's plan to modernize its aging nuclear weapons complex and update the seven hydrogen bomb designs in the nation's arsenal would require massive investments at a time of severe budget pressure.
As a result, the plan is getting a tough assessment by outside groups, who say congressional Republicans and Democrats are not fully on board with what the Obama administration has proposed over the last year: a $60 billion effort that would transform industrial arms sites across the nation and fundamentally reconfigure existing weapon designs.
A report this week by the Union of Concerned Scientists raises new objections that the plan would require construction of unnecessary facilities and introduce untested combinations of parts inside the bombs - which could erode confidence in their reliability and safety.
At the same time, the report confirmed long-standing concerns cited by nuclear weapons experts that not enough routine testing and surveillance of the nation's stockpile is being conducted at bomb plants to assure full reliability of the weapons. In recent years, funding for surveillance has increased and is scheduled to grow.
The U.S. stopped making nuclear weapons in 1990, meaning that all stockpiles are at least 23 years old and in many cases 30 or 40 years old. The Energy Department has proposed and withdrawn a number of plans to deal with the aging stockpiles.
After those earlier plans were criticized, the Nuclear Weapons Council, a high-level board of officials from the Energy and Defense departments, proposed a 25-year plan to mix old and newly manufactured parts from the seven existing weapons designs into five new packages at a cost of $60 billion.
The new report from the scientists group faulted that plan, because it would combine plutonium triggers from one type of weapon with thermonuclear components from other types. That kind of combination was never tested by detonation before the end of full-scale underground tests in the early 1990s.
Among the authors of the report was Philip Coyle, who at one time ran the nation's nuclear testing program in Nevada, later was deputy director of the Lawrence Livermore National Laboratory, and until 2011 served as associate director for national security and international affairs in the White House Office of Science and Technology Policy. Coyle said the current plan essentially violates the Obama administration's pledge against developing new nuclear weapons.
"It sends the wrong message to the rest of the world," he said.
The Energy Department and its National Nuclear Security Administration, which runs the weapons complex, did not respond to Times requests for comment on the report.
Instead of developing new designs that could not be tested under current international treaties, the Obama administration should continue to refurbish existing designs at a much lower cost, said physicist Lisbeth Gronlund, a co-author of the report.
"Both parties are concerned about the cost of these things," she said.
The report also called on the Energy Department to get rid of its surplus stocks of plutonium and uranium, in part by blending the material for use as commercial nuclear reactor fuel. The Energy Department has enough material for 13,000 new nuclear bombs, according to the report.
The Obama plan would include a number of costly new production facilities, including the Uranium Processing Facility, a massive plant at the Y-12 Security Complex in Tennessee slated to manufacture new thermonuclear secondaries for bombs. The cost of that facility has jumped from $600 million to $7 billion, according to the Union of Concerned Scientists report, and other estimates put the cost as high as $11.6 billion.
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