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Japan’s plutonium problem

 Japan’s plutonium problem
Peter Wynn Kirby, The New York Times, Aug 16, 2015
http://www.nytimes.com/2015/08/17/opinion/japans-plutonium-problem.html
  accessed Aug 17, 2015
  
這是多數人忽略的問題:日本擁有47頓鈽,而安全儲藏是個大問題。
 OXFORD, England — When Japan marked the 70th anniversary of Nagasaki’s obliteration by a plutonium bomb on Aug. 9, its own cache of weapons-usable plutonium was more than 47 metric tons — enough to make nearly 6,000 warheads like the one that flattened Nagasaki.
 
Japan, an industrial powerhouse but resource-poor, has long depended on nuclear energy. Before the earthquake and meltdowns at Fukushima Daiichi in 2011, it was generating nearly one-third of its electricity from nuclear power, and had plans to increase that share to 50 percent by 2030. Japan’s 48 standard reactors burn uranium fuel, a process that yields plutonium, a highly radioactive and extremely toxic substance.
 
These reactors were shut down after Fukushima. But Japan still stores nearly 11 tons of plutonium on its territory (the rest is abroad for now), and stockpiling plutonium remains hazardous: There is seismic instability, but also the risk of theft by terrorists. Yet just this week, Japan put one reactor back online, and another four have been approved for restart by the end of FY2015.
 
For this, one can thank a powerful network of utility companies, conservative politicians and bureaucrats in Japan, who peddle the notion that plutonium constitutes a sort of thermodynamic elixir. A byproduct of burning uranium, plutonium itself can be processed in so-called fast-breeder reactors to produce more energy. That step also yields more plutonium, and so in theory this production chain is self-sustaining — a kind of virtuous nuclear-energy cycle.
 
In practice, however, fast-breeder technology has been extremely difficult to implement. It is notoriously faulty and astronomically expensive, and it creates more hazardous waste. By the 1990s, many countries that experimented with fast-breeder reactors, including the United States, had phased them out.
 
But Japan doubled down. The government invested heavily in Monju, a prototype fast-breeder reactor, and the nuclear industry went on a charm offensive. It introduced Mr. Pluto, a puckish animated character, who claimed plutonium was safe enough to drink. It set up so-called PR centers next to nuclear plants: An exhibit at the one near Monju declared that the reactor was “necessary because plutonium can be used for thousands of years.”
 
The exhibit did not say Monju was a failure. The reactor became operational in 1994, but was shut down the next year after a leak caused a coolant to catch fire. Then came a botched cover-up, more than a decade of repairs, a failed restart and another accident. Monju has cost about $12.5 billion so far and produced only a tiny amount of energy.
 
In 1993 Japan also started spending a fortune on a reprocessing facility at Rokkasho, which would transform nuclear waste into fuel by separating plutonium and usable uranium from other waste. The process also is extremely expensive, and it, too, creates huge amounts of waste. Scheduled to begin operations in 2016, the plant could add as many as eight tons of plutonium to Japan’s stockpile each year.
 
While Japan’s record with nuclear waste is abysmal, no other state has found a safe or economically sustainable way to reuse such substances, especially not plutonium. Britain has announced it will abandon its costly and highly toxic reprocessing efforts by around 2020. The United States has a program to recycle nuclear byproducts into a mixed-oxide fuel known as MOx, a blend of uranium and plutonium. But the Obama administration has put it on stand-by because of ballooning costs.
 
France, which is at the forefront of MOx conversion efforts, has also struggled and is expected to phase out its MOx program by 2019. Instead, it has announced plans to start building in 2020 a new kind of fast-breeder reactor, known as ASTRID. This reactor is designed to generate energy by converting high-level nuclear waste into less dangerous residues, which require storage for several hundred years rather than many thousands of years, as is the case with plutonium. But this project has been delayed until at least 2030.
 
By far the best way to handle plutonium is to store it in secure long-term repositories underground. Having long banked on conversion, neither France nor Britain has permanent facilities; they keep plutonium in interim storage at reprocessing plants. Only two states have begun building viable long-term storage. Finland is constructing a vast facility blasted out of granite, which should be usable as of 2020. In the United States, underground chambers that can accommodate 12 metric tons of plutonium have been dug in New Mexico.
 
Considering Japan’s many vulnerabilities, particularly seismic activity, nuclear waste should no longer be stored there. The Japanese government should pay its closest allies to take its plutonium away, permanently.
 
Britain already holds about 20 tons of Japan’s plutonium, and France, about 16 tons, under contracts to reprocess it into usable fuel. Under current arrangements, this fuel, plus all byproducts (including plutonium), are to be sent back to Japan by 2020. Instead, Japan should pay, and generously, for that plutonium to stay where it is, in secure interim storage. And it should help fund the construction of secure permanent storage in Britain and France.
 
The Japanese government should also pay the United States to take the nearly 11 tons of plutonium currently in Japan. This proposal will seem controversial to some Americans, but the two states already have arrangements for the exchange of nuclear material. (With Finland, however, the proposition is a political nonstarter.) But it will take many years to build additional permanent storage in the United States -- and overcome likely opposition in Congress -- so in the meantime, Japan’s plutonium should be stored in interim facilities at American plants.
 
Handling Japan’s plutonium would be a great burden for receiver countries, and Japan should pay heftily for the service. But even then the expense would likely amount to a fraction of what Japan spends on its ineffectual plutonium-energy infrastructure: By the most conservative estimate, the Rokkasho facility is expected to cost $120 billion over its 40-year lifetime.
 
The benefits of this policy would extend far beyond Japan. An earthquake near Rokkasho could trigger an unprecedented nuclear catastrophe; preventing such an accident is in the whole world’s interest. And by funding the construction of long-term storage facilities overseas, Japan wouldn’t just be solving its plutonium problem. It would also be helping other states mitigate their own.
 
Peter Wynn Kirby is a nuclear and environmental specialist at the University of Oxford.
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