Nuclear fuel cycle in a stalemate (2)

November 5, 2015

Editorial: Decommission trouble-plagued Monju fast-breeder reactor

http://mainichi.jp/english/english/perspectives/news/20151105p2a00m0na007000c.html

The Nuclear Regulation Authority (NRA) has decided to recommend that the Japan Atomic Energy Agency (JAEA) be replaced by another entity as the operator of the trouble-plagued Monju prototype fast-breeder nuclear reactor. The NRA is set to issue the recommendation to the education, culture, sports, science and technology minister, the regulator of the JAEA, under the Act for Establishment of the NRA. The authority also intends to fundamentally review the Monju project and even consider the possibility of decommissioning the reactor if the science minister cannot find and name an alternate operator in six months.

Monju situated in Tsuruga, Fukui Prefecture, has hardly been in operation since a sodium leak in 1995. The JAEA and the ministry explored the possibility of the organization's structural reform and reviewed safety measures for the reactor. However, misconduct-related incidents have continued at the JAEA. It is only natural that the NRA has deemed that the operation of Monju should not be left to such an organization.

The government has promoted the so-called nuclear fuel cycle project, in which spent nuclear fuel is reprocessed and plutonium extracted from the fuel is used as fuel for atomic power stations. Fast-breeder reactors are the core of the project. The ministry is poised to retain Monju while seeking to cooperate with the private sector and overseas nuclear energy-related organizations involved in the project.

However, fast-breeder reactors pose challenges in terms of both technology and costs.

The operation and maintenance of the Monju reactor using liquid sodium, which easily catches fire if exposed to the air, as coolant, requires a higher level of skill than conventional nuclear reactors that use water as coolant. At least 1 trillion yen in taxpayers' money has so far been spent on the reactor. The annual maintenance costs for the reactor amount to approximately 20 billion yen. Nevertheless, there are no prospects that fast-breeder reactors can be put into practical use in the foreseeable future. It is also feared that Monju is aging.

These fundamental problems are highly unlikely to be solved simply by replacing the reactor's operator. The government should decommission the prototype fast-breeder reactor.

It came to light in November 2012 that the JAEA failed to inspect about 10,000 parts of Monju, and the NRA responded by instructing the agency to suspend operations at the reactor. However, new misconduct-related incidents surfaced one after another, prompting the NRA to decide to recommend that the JAEA be replaced as the Monju operator.

The recommendation will be issued purely to respond to safety-related problems at a nuclear facility. Still, a review of Monju could lead to debate on the nuclear fuel cycle project as a whole.

There are no prospects for starting operations at a nuclear fuel reprocessing plant that Japan Nuclear Fuel Ltd. is building in the Aomori Prefecture village of Rokkasho. However, the completion of the facility has been repeatedly postponed because of technical problems and safety inspections by the NRA. The construction costs, which had been initially estimated at 760 billion yen, have increased three-fold.

Even if the reprocessing plant is to be put into operation, plutonium to be extracted from spent nuclear fuel would have nowhere to go as long as the development of fast-breeder reactors remains deadlocked. Moreover, progress cannot be made on a project to use plutonium extracted from spent nuclear fuel for conventional nuclear plants.

Since the nuclear fuel cycle project has obviously been deadlocked, the government should immediately begin to seriously consider permanently shutting down the project.