Interview with Tatsujiro Suzuki, vice-chairman of the Japan Atomic Energy Commission, on Japan’s surplus of plutonium

by Yumi Kanazaki, Editorial Writer

Plutonium extracted from spent nuclear fuel from Japan’s nuclear power plants is mixed with uranium, the intention being to turn this into usable MOX fuel. But the amount of plutonium has grown to such a degree that there is now enough of the substance to produce 5,500 Nagasaki-type atomic bombs. What should be done about this situation? The Chugoku Shimbun interviewed Tatsujiro Suzuki, the vice-chairman of the Japan Atomic Energy Commission, who has long pointed to this problem while supporting the continued use of nuclear energy in Japan.

Why has the amount of plutonium grown so large?
The main reason is that plutonium is being extracted based on the idea that all spent nuclear fuel must be reprocessed. Even with the resumption of “pluthermal” (plutonium-thermal) power generation, in which MOX fuel is burned in light water reactors, if the pluthermal project is not carried out as planned, or the spent fuel reprocessing plant in the village of Rokkasho, Aomori Prefecture, begins full-scale operations, our stock of plutonium will increase further.

A critical eye has been cast on Japan’s excess plutonium.
Japan is the only non-nuclear weapon state with a commercial-scale reprocessing facility. With regard to nuclear non-proliferation, criticism directed toward Japan for possessing plutonium, which can be diverted to military use, is greater than imagined. Recently, a U.S. assistant secretary of state warned that this situation could cause damage to Japan’s reputation.

Local residents in Fukui Prefecture are voicing strong criticism over MOX fuel, processed in France, being brought into the Takahama nuclear power plant, operated by the Kansai Electric Power Company.
This is not necessarily incompatible with the principle that plutonium which has already been processed should be put to early use. But I can understand this reaction because the MOX fuel was brought in while the restart of the facility remains undecided.

How much pluthermal power generation is needed to increase the consumption of MOX fuel?
Japan owns 35 tons of plutonium in the United Kingdom and France, which were commissioned to reprocess the fuel, plus nine tons at home. That’s a total of 44 tons. If MOX fuel is used at 16 to 18 reactors, we’ll definitely see the stock reduced, even if the Rokkasho plants starts reprocessing.

Even prior to the nuclear accident at the Fukushima No. 1 (Daiichi) nuclear power plant, only four reactors were being used. These numbers seem far from realistic.
Considering the uncertainty of our future nuclear policy, a more flexible approach should be taken in terms of consuming plutonium. There are some ideas worthy of consideration, such as requesting that the U.K. take what is stored in their country.

This past March, you proposed guidelines to avoid producing excess plutonium and you expressed these ideas as a personal view in an email newsletter issued by the Atomic Energy Commission.
My main point is a policy shift from taking for granted the reprocessing of all spent fuel to adjusting the supply to the demand. Power companies should have a clear picture of how much MOX fuel is needed, when and where, and reprocess only this necessary amount.

The important point is matching supply to demand.
The original impetus for reprocessing was to provide fuel for fast breeder reactors (FBRs), which are considered central to the nuclear fuel recycle. But the commercial operation of FBRs is delayed and the pluthermal power generation project is not advancing as planned. Still, the policy of reprocessing all spent fuel has not changed.

Don’t you think the answer is to stop reprocessing and operating FBRs?
About FBRs, my personal view is that it’s enough to address technology development through international cooperation. But if we stop reprocessing facilities, the huge amount of spent fuel brought to the Rokkasho plant will have nowhere to go. On average, the pools at nuclear power plants, where spent fuel is temporarily stored, are 70 percent full. The pools at Rokkasho are almost full. We also have to consider the impact on employment and the local economies. The final disposal sites for high-level radioactive waste haven’t been determined yet.

How can the problem be solved?
Last year, the nuclear fuel cycle subcommittee of the Japan Atomic Energy Commission compiled a report on policy options with different levels of dependence on nuclear energy. One of the suggestions it made was to combine reprocessing and direct disposal into the ground. While securing storage to hold spent nuclear fuel for several decades, reprocessing should continue. Meanwhile, we can select sites for underground disposal and conduct technological research. In this way, we can be flexible about choosing a future course.

What was the reaction to the report?
Since it was submitted to a cabinet meeting, it has been in limbo. The fact that a draft of the report had been sent beforehand to some of the parties concerned was considered problematic, and I deeply regret these events. Still, the conclusion, which is the consensus of subcommittee members, and the contents of our discussions must be respected even after the change of administrations. It would be regrettable if they chose to maintain the status quo without raising the level of policy debate. I would like to do what I can so that the report will be put to appropriate use.


Tatsujiro Suzuki
Born in Osaka, Tatsujiro Suzuki graduated from the faculty of engineering at the University of Tokyo in 1975. After obtaining a master’s degree from the Massachusetts Institute of Technology, he received his doctoral degree in engineering from the University of Tokyo. Dr. Suzuki served as a senior research scientist at the Central Research Institute of Electric Power Industry, and a visiting professor at the Tokyo University’s Graduate School of Public Policy, before assuming the post of vice-chairman of the Japan Atomic Energy Commission in January 2010 under the government of the Democratic Party of Japan. His main fields of research include nuclear policy and nuclear non-proliferation policy. Dr. Suzuki also served as a council member of the Pugwash Conferences on Science and World Affairs, an organization of scientists dedicated to the elimination of nuclear weapons.

(Originally published on July 3, 2013)