Back-sliding on Monju Nuke Info Tokyo No. 107

“OK. They’ve won their court case. Now perhaps they can let Monju go.” Thus spoke CNIC Co-Director Baku Nishio, attempting to put a favorable light on the Supreme Court’s rejection of the twenty-year struggle of residents opposed to the construction and operation of the Monju Prototype Fast Breeder Reactor (280 MW FBR) in Tsuruga, Fukui Prefecture. He said this knowing from bitter experience how stubbornly Japanese politicians and public servants cling to policies to which they have once committed themselves. It seems to have less to do with the practical merits of the policy and more to do with saving face. Maybe now at last they can feel that their faces are not in danger.

Waiting for the verdict (photo by Hidemichi Kano)

Interestingly, within two weeks of the Supreme Court decision newspaper reports suggested that Monju was not the top priority project in Japan’s nuclear development strategy. An article in the Asahi Shimbun, a leading daily national newspaper, included the following claim: “In a policy shift, the government will upgrade existing light-water nuclear reactors and shelve its fast-breeder reactor plans for the nation’s power needs over the next few decades, officials said Thursday.” (11 June 2005) The official quoted was from the Nuclear Energy Policy Planning Division of the Agency for Natural Resources and Energy. This agency is an affiliate of the Ministry of Economy, Trade and Industry, the ministry responsible for nuclear energy development.

Actually, this policy shift was inevitable, since FBRs won’t be developed in time to replace the current fleet of light water reactors. It is still official government policy to proceed with FBRs, although they are not expected to be operating on a commercial scale until around 2050. The Monju prototype itself is supposed to recommence operations around February 2008. However, the timing of this announcement suggests that the administration realizes that the Supreme Court decision isn’t the FBR’s biggest hurdle. Of far greater significance are the questions of whether a sodium cooled fast reactor can ever be operated safely and economically and whether the ‘B’ part of FBR will ever work according to theory. The latter question can be rephrased as, “Will FBRs ever succeed in breeding more plutonium than they consume?” After all, that is the whole purpose of this type of reactor. FBRs are supposed to turn all the world’s uranium reserves into plutonium, thus multiplying the energy generating potential of this fuel source sixty fold and solving the world’s energy problems for thousands of years.

Returning to the Supreme Court verdict, the decision overturned a January 2003 ruling by the Nagoya High Court that the Monju license approval was invalid (NIT 93, 104). The High Court had concluded that three major flaws in the Nuclear Safety Commission’s (NSC) safety assessment made it invalid. Each of these flaws entailed the possibility that there could be a release of radioactivity into the environment. It concluded that the flaws were too serious to be overlooked and had resulted in an unreasonable decision to approve construction of Monju.

The first flaw related to the steel floor liner. This was designed to prevent any sodium leak from leading to contact between sodium and the concrete floor. Such contact could lead to an explosive reaction between the sodium and the water in the concrete. The safety assessment underestimated the temperatures that could result from a sodium leak. It also failed to take into account the phenomenon of erosion resulting from an interface reaction involving sodium, steel and oxygen. A major reason why the High Court found in the citizens’ favor on this issue was the December 1995 sodium leak. Although the liner was not breached, information that came to light as a result of that accident in regard to the abovementioned erosion phenomenon and the high temperatures reached clearly revealed the flaws in the original safety assessment. Monju has been closed since this accident¹.

The second flaw related to the steam generator. Here heat is transferred from the secondary sodium coolant to pipes with water and steam running through them. If water or steam were to leak out through holes in these pipes, there could be an explosive reaction with the sodium. The safety assessment considered only ‘wastage’ as a cause of any such leakage. It didn’t consider the phenomenon of ‘high temperature rupture’. This phenomenon has the potential to cause many more pipes to rupture than in the case of wastage. The fact that such a rupture could occur was demonstrated by a 1987 accident at the UK Prototype Fast Reactor, but this accident was covered up for many years.

The third flaw related to the potential for a reduction in primary coolant to lead to a loss of control over the reactivity of the core. The safety assessment failed to consider higher estimates that had been made of the energy which could theoretically be released and it discounted the possibility that such a situation could lead to a collapse of the core.

In overruling the Nagoya High Court’s verdict, the Supreme Court looked at each of these alleged flaws and essentially concluded as follows:
1. It was not the role of NSC’s safety assessment to assess the detailed design features of the steel floor liner. Matters such as thickness and other dimensions could be addressed at later stages of the approval process. NSC’s role was to assess the ‘basic design’ only, and at this stage it was sufficient to conclude that there would be a steel liner and that, in theory, specific dimensions could be selected that would prevent contact between sodium and the concrete floor in the event of a sodium leak.
2. There were a number of safety features that would act as a back up in the case of a high temperature rupture in the steam generator.
3. Overseas examples of standards and analyses were proposed by the citizens as evidence that the Monju safety assessment underestimated the energy that could potentially be released, but these examples could not be generalized to Monju.

Hence, the Supreme Court concluded, it was not reasonable to conclude that the approval contained flaws that could not be overlooked, or that the approval was unreasonable.

What the Supreme Court didn’t say was that Monju was safe to operate. It followed a very narrow line of argument designed only to confirm that NSC’s safety assessment was “not unreasonable” and that it didn’t “contain flaws that could not be overlooked”. In doing so, it excluded indisputable design defects on the grounds that they were beyond the scope of this particular step in the safety assessment process, it failed to address serious doubts about whether safety systems would actually work as designed, and it ignored the clear similarities between the overseas examples and Monju. So regardless of whether or not the verdict could be justified on technical grounds, it did nothing to resolve the biggest obstacles facing Monju and the FBR program (identified above as safety, economics and plutonium breeding).

The lawyers representing the citizens have concluded that the decision was incorrect. They say it also exceeds the Supreme Court’s authority. The Supreme Court is supposed to review the legality of the High Court’s decision on the basis of the ‘factual matters’ presented to the High Court, but in this case it introduces new ‘factual matters’. On June 28th the citizens lodged an appeal for a review of the decision. One would presume that their chances of success are not high, but it is easy to understand the feeling that, after coming so far, they should give it this one last shot.

However, as things now stand, this verdict will make it very difficult for future challenges to nuclear power plant licenses. It won’t be enough to prove that the safety assessment failed to ensure that the reactor could in fact be operated safely. It will be necessary to argue, from the standpoint of the safety reviewers themselves, that the approval was unreasonable. Whereas the Nagoya High Court demanded that the NSC safety review address all factors that could lead to a major accident and prove that such an accident could not occur, the Supreme Court left these judgments to the NSC experts. In that sense, it was a victory for the technocrats. It could be said that whereas the Nagoya High Court followed the precautionary principle, the Supreme Court threw caution to the wind.

As reported in News Watch 105, preparations have begun for modifications to Monju. These will include replacement of the temperature gauge which was the cause of the sodium leak accident in 1995. There will be opportunities before the scheduled restart in February 2008 to block the operation of Monju. The Fukui governor approved these modifications, but that doesn’t mean that he won’t be responsive to public pressure in future. Monju remains a very unpopular nuclear reactor. The Supreme Court decision has done nothing to alleviate public distrust, so the struggle goes on.

Philip White (NIT Editor)

1. As one reader pointed out to us, it is an over-simplification to say that Monju has been closed since the 1995 accident. For reasons of space and simplicity we didn’t elaborate when this article was published, but in fact Monju has continued to consume a large quantity of electricity ever since the accident. Most of the electricity consumed is used to heat the sodium liquid, which remains in the reactor.

Details of electricity consumption for 2004 were as follows:
Hokuriku Electric Power Company was contracted to provide 70,127,000 kWh in 2004 at a price of 695,572,563 yen. In fact, the final consumption for that year was only 58,533,960 kWh, but being a fixed price contract, the price did not change.

That huge waste of electricity and of tax payers’ money has been going on for 10 years and will continue for quite a while yet. Indeed, there is no guarantee that Monju will ever begin to recoup that loss by generating electricity itself.