The Mainichi answers some common questions readers may have about nuclear waste disposal in the wake of the crisis at the Fukushima No. 1 Nuclear Power Plant.
Question: Where does the radioactive waste created by nuclear power plants come from?
Answer: At nuclear power plants, the radioactive material uranium undergoes nuclear fission, providing energy. The product left over after this process is referred to as “spent nuclear fuel.” Japan is promoting a nuclear fuel cycle in which uranium and plutonium are extracted from this spent fuel and reused, but high-level radioactive material that can’t be reused is left behind as radioactive waste.
Q: How much of this radioactive waste is produced?
A: In Japan there are about 1,700 rods of nuclear waste stored at Rokkasho, Aomori Prefecture, and Tokai, Ibaraki Prefecture. The rods, each of which stand about 130 centimeters tall and weigh some 500 kilograms, are made by mixing spent nuclear fuel with melted glass. Under government estimates there will be roughly 40,000 of these rods in Japan by about 2021.
Q: How does Japan plan to dispose of these 40,000 rods?
A: Japan has decided to build a final disposal facility for high-level radioactive waste, enclose the glass rods in steel containers and bury them at least 300 meters below the ground. The rods emit strong radiation, and it is said that it would take tens of thousands of years for this radiation to fall to a level matching that of natural uranium deposits.
Q: That’s a long time. So where is this final disposal facility?
A: So far, there are still no permanent repositories in the world for high-level radioactive waste, though Finland and Sweden have finalized building locations. In Japan, an organization authorized by the Ministry of Economy, Trade and Industry has from December 2002 been publicly seeking local bodies willing to host a final repository. By simply signing up for an initial survey into building a site, a local body could receive as much as 2 billion yen in subsidies. In January 2007 the Kochi Prefecture town of Toyo became the first municipality to apply, but the town assembly and residents opposed the project, and the mayor who was later elected withdrew the application.
Q: The government is asking that nuclear reactors not in operation be restarted, but at its current pace, Japan will one day end up with more nuclear waste than it can handle, won’t it?
A: Japan has 54 nuclear reactors, the third most of any country in the world. Since the outbreak of the nuclear crisis in Fukushima Prefecture, countries in Europe and other places have moved to phase out nuclear power, but they cannot avoid the problem of settling on a final disposal facility for radioactive waste that they have already produced. All of us who have enjoyed a stable source of electricity from nuclear power must think about this issue and discuss it in greater depth. (Answers by Takayuki Hakamada, City News Writer)
