Friday, March 17, 2006

Terror risks of nuclear fuel

Terror risks of nuclear fuel

By Mark Clayton Staff writer of The Christian Science Monitor
The Bush administration's plan to deploy a high-tech fuel to power a new generation of nuclear reactors worldwide has a potentially explosive problem:
It is too easy for terrorists to grab and turn it into a nuclear bomb.
That's the criticism expressed by nuclear scientists and in several little-known federal studies about the technology underlying the Global Nuclear Energy Partnership, unveiled last month. Administration officials tout GNEP for technological breakthroughs that dramatically reduce the nuclear waste from civilian reactors and, at the same time, greatly reduce the risk of nuclear proliferation.
Using GNEP's new fuel technology, called UREX-Plus, the United States could safely end its three-decade moratorium on reprocessing spent nuclear fuel intended to keep plutonium from spreading, officials say. "The goal of GNEP is recovery of the energy in a way that doesn't promote weapons," Energy Secretary Samuel Bodman told a US Senate committee last month.
Knowledgeable critics have said from the outset that the new reactor fuel envisioned in GNEP is not so very hard to turn into bombs. But what has not been widely known is that their views are echoed by the US Department of Energy's own studies. According to a 2004 study conducted for an Energy Department blue-ribbon commission, for instance, the UREX-plus technology was only slightly more "proliferation resistant" - difficult to turn into bombs - than the PUREX process used by other nations. The US has often criticized PUREX for its vulnerability.
"The bottom line is that UREX-plus is not much more proliferation resistant - by their own estimates," says Henry Sokolski, former deputy for nonproliferation policy at the Defense Department in the first Bush administration.
To be proliferation resistant, nuclear material should be so radioactive it would be deadly to handle, nearly impossible to divert without detection, and fiendishly difficult to refine into weapons fuel. UREX-plus falls well short by all three measures, according to federal reports.
For example: Any such reactor fuel should be so radioactive that it would be "self-protecting." The National Academy of Sciences calls for a "spent fuel standard" for plutonium. That means it should be so radioactive - emitting 1,000 rads per hour at arms-length - that anyone trying to steal it would receive a lethal dose of radiation within 30 minutes. It also means it should be as difficult to transport as a 12-foot-long assembly of nuclear fuel rods weighing half a ton or more.
But UREX-plus, as developed and as presented to Congress until recently, would emit less than 1 rad per hour, according to a November report from the Energy Department's Oak Ridge National Laboratory. Even using the lower standard for plutonium developed by the International Atomic Energy Agency, that's 1/100th of the necessary level for self-protection.
The UREX technologies "would still produce a material that is not radioactive enough to deter theft and could still be used to make nuclear weapons," says Edwin Lyman, a physicist with the Union of Concerned Scientists.
"UREX-plus is just PUREX with lipstick," adds physicist Frank von Hippel, former assistant director of national security in the White House Office of Science and Technology:Supporters say critiques are outdated
Government scientists say UREX-plus is much better than critics say it is.
"There's only one step where this material has low self-protection, not up to the max, and then it's heavily guarded," says Phillip Finck, deputy associate laboratory director at Argonne National Laboratory in Argonne, Ill., and the administration's top scientific spokesman on UREX. "This process, UREX-plus, is much more proliferation resistant than things developed in the past."
And the Energy Department's 2004 study that rated UREX-plus only slightly above PUREX "should be performed again in view of the real technological changes since then," he adds.
Nevertheless, Dr. Finck in a presentation to congressional staff last Friday proposed a major change to UREX-plus that would add the radioactive element europium to the mix. That change is intended to boost the fuel's self-protection level, but it would also require additional refining capability at each "advanced fast-burner" reactor site, costing many billions more than the price tag US Energy Secretary Bodman offered in congressional hearings last month, several experts say.
So far, the government has proposed spending $250 million on GNEP planning and development. If GNEP gets the green light, it would cost another $3 billion to $6 billion over five years to get engineering scale demonstration facilities going and perhaps $20 billion to $40 billion overall, Bodman says.
But with the US needing dozens of reactors and reprocessing plants to meet demand, the cost could rise into hundreds of billions of dollars, according to early Energy Department estimates and the National Academy.
Radioactivity isn't the only defense against terrorists and rogue states. Another key is whether the plutonium-based fuel can be measured accurately. Plutonium is a sticky substance that gets caught in nooks, and crannies, like drains. The more accurately it can be tracked, the less likely an employee at a civilian reactor could divert small amounts without getting caught, a strong point for UREX-Plus, Finck says.
But the plutonium in UREX-plus would be in powder and liquid forms and mixed with other materials, known as minor actinides or MAs. And this mixture, which is intended to make it harder for terrorists to extract the plutonium, could make it very hard to measure, government scientists say.
"Even small concentrations of MAs in plutonium mixes could complicate the accuracy of the plutonium measurement if not properly taken into account: consequently, safeguards of plutonium could be affected," Los Alamos scientists wrote in a 1996 study.
A third test of a fuel's proliferation potential is whether it can be readily used as bomb fuel with little further refinement. With PUREX, the reprocessing technology now used by Britain, France, Russia, and Japan, it's clear that its plutonium oxide output could be swiftly and easily converted to metallic plutonium for a bomb, experts say.
By contrast, UREX-plus fuel "is not attractive or useable as weapons material," said Clay Sell, deputy secretary of Energy at a press conference unveiling the GNEP program last month.
But that's not what several energy Department scientists have concluded. They found that plutonium-based reactor fuels with various impurities can still be used in a crude or even an advanced nuclear weapon.Fuel could become bomb, study says
A "subnational group using designs and technologies no more sophisticated than those used in first-generation nuclear weapons could build a nuclear weapon from reactor-grade plutonium," a 1997 DOE study found. The explosion would be on the scale of the bomb that was dropped on Nagasaki, Japan, in World War II. But even a "fizzled" explosion would mean a one-kiloton explosion, enough to devastate the core of a major US city.
True, that study did not evaluate the "minor actinides," elements included in UREX-plus, such as americium and neptunium. But more recent DOE analysis indicates such elements are not much, if any, real obstacle to the fuel's use in a weapon. Indeed, UREX-plus would contain americium and neptunium, nuclear elements with explosive properties any terrorist or a rogue state could well appreciate, government physicists say.
"As nuclear weapon design and engineering become more common in the world, it becomes possible to make nuclear weapons out of an increasing number of technically challenging explosive fissionable materials," including the likes of americium, wrote a DOE scientist in a 1999 report.
Such fears are largely unfounded, counters Finck at Argonne. "Theoretically, yes, you could use it [in a bomb.] But it would be an extremely difficult process. I can't comment further on that."
Common security measures, he adds, such as close-in surveillance cameras, real-time computer tracking of material, guards, guns, and fences at UREX-plus reprocessing plants, in tandem with technical challenges would make the fuel very difficult to steal.


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