Japan Restarts Troubled Breeder Reactor

TOKYO—Fourteen years after a coolant leak and botched cover-up led to its shutdown, Japan's Prototype Fast Breeder Reactor Monju was restarted today with the hope of moving the controversial technology toward wider commercialization.

"Building on the many lessons of these 14 years, we will ensure safety as the highest priority for Monju while striving to enhance the transparency of our operations," said Japan Atomic Energy Agency (JAEA) President Toshio Okazaki in a Japanese statement. Not everyone is convinced. "Safety, economic and nuclear proliferation issues are being ignored for purely bureaucratic reasons," the Tokyo-based Citizens' Nuclear Information Center protested on its English Web site.

Conceived in the 1970s, Monju was once at the leading edge of research into fast fission reactors, which have always been controversial because they burn plutonium, an ingredient in bombs. Fast reactors can "breed" more plutonium than they consume and can also transmute, or burn up, waste from conventional nuclear power plants.

Built on a remote JapanSea promontory near Tsuruga, Monju achieved self-sustaining nuclear fission in April 1994. In December 2005, over 700 kilograms of molten sodium coolant burst through a pipe, releasing toxic fumes and damaging the plant. Officials initially dismissed the accident as trivial—and incurred public outrage. Much of the subsequent time and effort put into readying Monju for a restart went into convincing government officials and the public that more accidents were unlikely and that there would be no more cover-ups. The last hurdle was a nod of approval from the prefectural government that came late last month.

Fast reactors still have fans. Thierry Dujardin, an official with the Organisation for Economic Co-Operation and Development's Nuclear Energy Agency in Paris, told Science for a 27 February 2009 article that fast reactors could help reduce nuclear waste and cut greenhouse gas emissions. But experimental fast reactors in the United States, the United Kingdom, Germany, and France have all been shut down because of high costs and concerns over handling plutonium. According to the World Nuclear Association, Russia has been operating one commercial fast reactor since 1980; and China, India, and Russia are building or planning new fast reactors for both research into next-generation designs and power production. JAEA engineers are also designing a next-generation fast reactor, but there has been no decision on actually building it.