Nuclear disposal - First Japanese study of underground disposal

 October 28, 2013

Challenges to nuclear waste disposal

http://www3.nhk.or.jp/nhkworld/english/news/20131028_44.html

The disposal of highly radioactive waste is said to be the biggest challenges facing nuclear power generation.

Japan has not yet decided where to build its disposal sites.

The government in 2000 enacted a law on nuclear waste disposal, and has since been calling on communities around the country to be candidate sites.

But no applications have yet been submitted.

The spent fuel from nuclear plants in Japan is currently taken to a facility at Rokkasho Village in Aomori Prefecture.

The facility currently stores more than 1,700 rods. In addition, power stations across the country are storing spent nuclear fuel equivalent to 25,000 such rods.

The science and technology ministry has launched a study to develop technologies that would reduce the impact of radioactive substances on the environment.

The study also aims to reduce the space needed for nuclear waste disposal to about one-hundredth of what it is today.

Oct. 28, 2013 - Updated 12:58 UTC

Govt. reviewing underground nuclear disposal plan

      http://www3.nhk.or.jp/nhkworld/english/news/20131028_42.html

Japan's industry ministry has long planned to bury spent nuclear fuel and other radioactive waste from power plants deep underground. But the search for storage locations has been in vain so far, leaving the permanent disposal of high-level waste in limbo.

The ministry has now set up a panel to reexamine the safety of the underground storage plan. It is the first review in 14 years.

On Monday, experts from 8 academic societies specializing in earthquakes, seismic faults, groundwater and other fields, held their first meeting.

At the panel, officials from a body in charge of nuclear waste management said that underground disposal is still considered safe, even with knowledge acquired after the 2011 earthquake and tsunami disaster in Japan.

But the panel's experts said that seismology cannot predict what might happen 100,000 years from now. They stressed that if magma were to hit a waste repository, leaked radioactive substances would affect other countries.

The head of the panel, Osamu Tochiyama, said the experts will reexamine the plan independently, from scientific viewpoints.

The ministry says the review process will continue until next March, and the panel's final report will be included in an study of nuclear waste disposal plans being conducted by another group.

Oct. 28, 2013 - Updated 12:29 UTC

Nuclear waste disposal tunnel shown to media

      http://www3.nhk.or.jp/nhkworld/english/news/20131028_38.html

A Japanese nuclear power research agency has showed the media an underground test tunnel in northern Hokkaido where it is working to devise methods for nuclear waste disposal.

At its research site in Horonobe, the government-affiliated Japan Atomic Energy Agency is studying safe ways of disposing of highly radioactive nuclear waste more than 300 meters underground.

The research tunnel was bored horizontally in a sedimentary rock formation at a depth of 350 meters.

The figure-eight-shaped tunnel has a total length of 760 meters.

Next fiscal year, the agency plans to start storing simulated radioactive waste containers in caves that extend from the tunnel. The containers feature heat sources that simulate nuclear waste. Work is now under way to extend the caves.

Researchers will try to determine whether they can safely store such nuclear waste deep under the ground without being affected by heat, groundwater or other factors.

Senior center official Tomoo Fujita says that this study of disposal in a tunnel in sedimentary rock will be the country's first.

He says his team wants to develop safe disposal methods by experimenting under a variety of conditions.

Oct. 28, 2013 - Updated 12:21 UTC