Japan’s Plutonium Problem
Data shows a major stockpile
Disposal solutions hard to find
The Japanese Nuclear Regulation Authority (NRA) recently released the latest data on Japan’s plutonium stockpile (please click here to view) the total of which is growing year by year and has almost reached 50 tons, enough to build over 10,000 nuclear weapons. The security risk of this large stockpile of such a dangerous substance is obvious, but it also poses threats to non-proliferation, as it can be seen by other countries as preparation for nuclear weapons production.
CNIC Co-Director Hideyuki Ban outlines some of the problems presented by the data and the enormous challenges to reducing the stockpile in the future. This is followed by a report of a CNIC open seminar where Tom Clements of Savannah River Site Watch spoke on the difficulties America is also facing in disposing of plutonium. As both Ban and Clements point out, with such a large plutonium stockpile already existing, as well as the immense unresolved safety issues at the Rokkasho Reprocessing Plant, Japan should not be considering commencing operations at this plant at all.
According to the latest data released by the NRA, Japan’s plutonium stockpile held in the UK increased from 2014 to 2015, despite the fact that Japan no longer sends spent fuel to the UK for reprocessing. This increase is the result of plutonium allocated through a multinational reprocessing contract, which is ongoing. Moreover in France, there is a 30kg reduction both in Japan’s “total plutonium” and its fissile plutonium, which is believed to reflect the nuclear loss which occurs when plutonium 241 transforms into americium 241.
Inside Japan, plutonium nitrate is produced at the Tokai Reprocessing Plant, and a portion of this is distributed to a fuel fabrication facility. However, presently no processing is taking place. Based on their assessment that Tokai Reprocessing Plant is unable to meet the seismic regulations introduced under the new regulation standards for nuclear facilities in Japan, JAEA (Japan Atomic Energy Agency) is moving toward decommissioning the plant. As such, no further plutonium separation will take place at Tokai. Concerning the processing of MOX fuel, Nuclear Regulation Authority head Shunichi Tanaka has indicated that all existing (MOX fuel) facilities that do not conform to these safety regulations will need to be replaced by new facilities (September 7, 2016, Regular Press Conference). However, considering that there is little hope for consuming the 4.1 tons of plutonium currently stored onsite, the question of how this plutonium should be processed or disposed of is a great challenge.
Inspections to determine whether the Rokkasho Reprocessing Plant meets the new regulations have required extensive time, and while scheduled for completion in early 2018, it is anticipated the deadline will be extended. There is a strong possibility that inspections at the adjacent fuel fabrication plant will also be delayed. Further, due to the small number of nuclear plants that utilize pluthermal and plutonium being restarted, plutonium consumption has been slowed, and it appears that Japan’s plutonium stockpile will not be reduced for the foreseeable future.
(Hideyuki Ban, Co-Director, CNIC)