July 1999

Radical Change in Japanese Plutonium Policy Upcoming?

Asahi News Service, July 16, 1999
By Akito Kuwayama

[Posted 22/07/1999]

Nuclear Power Rethink Time Fast Approaching

Japan is set to keep waste at site nuclear fuel in mothballs for several decades, instead of recycling it.

A bill to that effect an amendment to the law regulating the use of nuclear reactors passed the Diet earlier this month. The "interim storage" of spent nuclear fuel marks a significant departure from the current policy of reprocessing all spent fuel and using plutonium which is separated from it as reactor fuel.

The new policy which reflects the lag in the development of the plutonium-fueled fast-breeder reactor effectively means that some if not all of the spent fuel will never be reprocessed.

In other words, it will be unnecessary to produce plutonium for at least several decades. This is likely to change Japan's nuclear policy.

The current policy adopts the nuclear fuel cycle in which all spent fuel from the nuclear plants is reprocessed and plutonium is used as fuel. The idea is to produce more plutonium and use more of it. But the prospects for plutonium use are clouded. The operation of the "Monju," the prototype fast-breeder reactor, has been suspended since it caused an accident in 1995. It is not at all clear when, or even whether, the era of the fast-breeder reactor will arrive. The burning of plutonium in the thermal neutron (light water) reactor known here as "pluthermal" is a key method for plutonium use. But this process is only just starting this year. It is unclear how much plutonium will be consumed. Meanwhile, spent fuel continues to accumulate at home, already reaching about 7,000 tons.

The nuclear plants and a reprocessing plant now under construction in the village of Rokkasho, Aomori Prefecture, have a combined storage capacity of about 15,000 tons. However, used fuel is piling up at a rate of 900 tons a year, and that rate will increase in the coming years.

The Rokkasho plant will be capable of reprocessing only 800 tons a year even if it goes into full operation in 2005 as scheduled.

Interim storage is designed to resolve this situation. This will be done in two years. One way to achieve this is the "wet method," or storing spent fuel in water pools. The other is the "dry method," whereby it is stored in casks indoors. The electric power industry is planning to build two storage facilities, each with a capacity of 5,000 tons, by 2020. The advantage of interim storage is this: the reprocessing that is not required for the time being can be postponed until sometime in the future when an appropriate policy, one that is geared to the needs of the times, can be worked out.

Germany and Switzerland are moving toward abandoning their reprocessing policy. The likelihood is that they will discard spent fuel after a certain period of storage.

The United States is pushing a "once-through" program to discard all spent fuel without storage. The waste will be buried deep in the ground, but it can be recovered, if necessary, over a period of 300 years. So the possibility is left open that buried nuclear fuel might be recovered as an energy source. The Japanese government maintains that interim storage is a "stopgap measure" pending final reprocessing and that the reprocessing policy therefore remains unchanged.

However, an official of the Science and Technology Agency suggests this policy may change in the future.

He said: "We can store spent fuel as an energy source for dozens of years. This gives us time to think out flexible responses."

Ban Hideyuki, co-representative and secretary-general of the Citizen's Nuclear Information Center, believes that interim storage will eventually put a permanent halt to reprocessing.

University of Tokyo Professor Atsuyuki Suzuki, speaking at a government forum on nuclear policy in June, proposed three options on the nuclear fuel cycle:

1. Discarding all spent fuel left after burning uranium in the light-water reactor (once-through formula).

2. Burning plutonium in the light-water reactor ("pluthermal" formula).

3. Burning plutonium in the fast-breeder reactor (fast-breeder-reactor recycling).

Suzuki called for a realistic debate on these options. It is worth noting that they include the once-through formula, which so far has been taboo for the nuclear power advocates. The question is when and where interim storage facilities will be constructed. This is a difficult question since selecting sites is easier said than done.

Tatsuya Murakami, the head of Tokaimura village, home to the reprocessing plant in Ibaraki Prefecture, told an Upper House committee recently that an electric power company had sounded him out over a tentative plan to build an interim storage facility. The plan, he said, had been conceived for the following reason: The storage capacity of the nuclear plant in the region served by the company has reached the limit, so the prefectural governor there wants extra spent fuel stored somewhere outside the prefecture.

"People always look to Tokaimura for help," Murakami complained. "With that kind of attitude, it is impossible to build a national consensus and develop a viable nuclear power policy. We should seek consistency of policy, not stop-and-go expediency."

So far Japan has been racing toward a perceived era of the fast-breeder reactor under a policy of complete fuel reprocessing. It is high time that this rigid policy was changed to a more realistic one.

Editor's note: The author is a staff writer in Asahi Shimbun's Science News Department.

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