10:26 8 March 2017
OPINION: A dangerous nuclear dinosaur
By Masafumi Takubo and Frank von Hippel
TOKYO/PRINCETON, New Jersey, March 8, Kyodo
During World War II, a small group of physicists in the United States designed the first three simple reactors that produced the plutonium for the nuclear test conducted July 16, 1945, at Alamogordo, New Mexico, the bomb that destroyed Nagasaki and, later, during the Cold War, for many thousands of other nuclear weapons that, fortunately, were not used.
Then they invented a much more complicated reactor -- a uranium-efficient plutonium breeder reactor that they hoped would solve humanity's energy problems for thousands of years.
Several industrialized countries, including Japan, embarked on efforts to build these liquid sodium-cooled breeder reactors but they proved to be costly, unreliable and prone to accidents.
And low-cost uranium was found to be one thousand times more abundant than originally assumed.
One by one, countries gave up the effort.
Japan, the most recent, decided at the end of 2016 to abandon its more than two-decade-long effort to operate its prototype breeder reactor, Monju.
France had previously made a similar decision in 1998, the United Kingdom in 1994, Germany in 1991 and the United States in 1983.
But these failed reactors are relatively unimportant compared to the huge "reprocessing" complexes that breeder programs have left.
The original mission of these complexes was to provide startup plutonium for the first wave of the expected fleets of breeder reactors by "reprocessing" the spent fuel of current-generation, water-cooled reactors to separate and recover the approximately 1 percent plutonium it contains.
The largest still-operating complexes of this kind are at La Hague in France and Sellafield in the United Kingdom.
The UK Government decided in 2011 to shut down its complex after the current reprocessing contracts are fulfilled.
Japan, on the other hand, currently plans to start the commercial operation of its complex at Rokkasho in 2018.
Unlike the United States and the United Kingdom, where failed breeder reactor programs were abandoned, France and Japan decided to keep separating plutonium and fabricate it into mixed-oxide (MOX) plutonium-uranium fuel for water-cooled reactors.
If the reprocessing kept up with the rate of discharge of spent fuel, it would be possible in this way to replace about 10 percent of the standard low-enriched uranium (LEU) fuel used in those reactors.
Producing the MOX fuel costs about 10 times as much as the LEU fuel that is being replaced but governments can require their electrical utilities to buy the costly MOX fuel and that is what France and Japan have done.
They justify this as an environmental measure, saying that it would be irresponsible to bury spent fuel containing plutonium, which will remain toxic underground for tens of thousands of years.
They maintain that the breeder reactor technology can be used in the future to burn and eliminate plutonium and other long-lived radiotoxic elements.
But studies in both France and Japan, as well as in Sweden and the United States, have found that the danger to the surface environment from deeply-buried spent fuel is not dominated by plutonium and, in any case, is not significantly greater than the danger from the uranium that was dug out of the ground and enriched and fabricated into LEU fuel.
(Masafumi Takubo is a consultant for Princeton University's Program on Science and Global Security. Frank von Hippel is a Senior Research Physicist and Professor emeritus with the program.)