Issues of HLW Disposal in Japan
Abstract Concerning the disposal of high-level radioactive waste (HLW) in Japan, the Nuclear Waste Management Organization of Japan (NUMO) has been making efforts toward beginning a literature survey, a first step of HLW disposal according to fundamental policies and final disposal plan based on the “Designated Radioactive Waste Final Disposal Act.” However, a difficult situation continues in which responses from municipalities, which are necessary for beginning a literature survey, are not being made.
In September 2010 the Science Council of Japan (SCJ) received a deliberation request from the Chairman of the Japan Atomic Energy Commission, and SCJ formed a Review Committee for Disposal of High-Level Radioactive Waste. The Review Committee made a Reply on Disposal of High-Level Radioactive Waste in September 2012, in which six proposals are made including safe temporal storage and management of the total amount of HLW. In this chapter, an outline of the current HLW disposal policy in Japan and the contents of the Reply are introduced.
Keywords Geological disposal • High-level radioactive waste (HLW) • Risk
• Temporal safe storage
Concerns on HLW
HLW stands for high-level radioactive waste. Concern about the safety of HLW disposal is another important element for the public in deciding their choice of nuclear power along with the safety issues related to nuclear power plant operation. Former Prime Minister Koizumi changed his political stance clearly after the Fukushima nuclear accident in March 2011, from pro-nuclear to anti-nuclear, mainly on the basis of his concern about the safety of HLW disposal.
Current Status of HLW
HLW contains very toxic fission products. Fission products in the spent nuclear fuels are highly radioactive. Some countries such as Finland, Sweden, and USA directly dispose spent nuclear fuels as HLW after cooling at spent fuel storage. According to the conventional nuclear fuel cycle policy, spent nuclear fuels in Japan are reprocessed for separating fission products from uranium and plutonium, and the separated fission products are vitrified and then contained in canisters made of stainless steel. The option of direct disposal of spent nuclear fuels was seriously discussed in the first time in Japan at the process for formulating the 2005 Framework for Nuclear Energy Policy, and after the Fukushima accident, direct disposal of the spent fuel is becoming a more realistic option.
Right now, 1,984 HLW canisters (vitrified wastes) are stored in Japan. Among the 1,984, 1,442 HLW canisters were sent back from France and UK according to the contracts for the reprocessing commissioned to these countries; the rest are the HLW canisters produced by domestic reprocessing (295 from the test operation of the Rokkasho reprocessing plant and 247 from the Tokai pilot reprocessing plant). An additional 770 HLW canisters will be sent back from the UK, and high-level liquid waste, which is equivalent to 630 HLW canisters, is stored at the Tokai pilot plant.
In addition to the HLW canisters produced by reprocessing, about 17,000 t of spent nuclear fuels is stored at nuclear power plants (about 14,000 t in total) and the Rokkasho reprocessing plant (around 3,000 t). If all these spent fuels are reprocessed at the Rokkasho reprocessing plant, about 21,250 HLW canisters would be added. Thus, even if Japan decided to no longer operate nuclear reactors, we still must dispose HLW equivalent to 24,634 HLW canisters. We cannot run away from HLW issues.