Japan's Monju experimental fast-breeder reactor faces one last hurdle before restarting  14 years after an accident and a botched coverup shut it down: An OK from the governor of Fukui Prefecture, which hosts the reactor. Shunsuke Kondo, chair of the Japan Atomic Energy Commission said today at a press conference that approval could come in May or June because it will likely take that long for negotiations between the governor and the central government to resolve remaining sticking points.
Monju was intended to demonstrate the practicality of using highly fissile plutonium as a nuclear fuel, instead of the uranium used in conventional nuclear power plants. The appeal is that, depending on the configuration, a plant using plutonium as a fuel can produce more plutonium than it consumes. The United States, the United Kingdom, Germany, France, Russia, and Japan built experimental fast reactors in the 1970s, '80s and '90s. But technical problems, costs, and concerns about safeguarding plutonium—an ingredient in nuclear weapons—led every nation but Japan to abandon the technology.
Monju achieved criticality in April 1994. In December 1995, a coolant loop leaked more than 700 kilograms of molten sodium, releasing toxic fumes and damaging the plant. Plant managers tried to cover up the accident; covertly recorded videos were leaked to the press.
There followed 14 years of repairs and redesigns of safety measures and attempts to rebuild public trust by Monju's operator, the Japan Atomic Energy Agency. All national agencies have recently given a Monju restart the green light. Only the Fukui governor, Issei Nishikawa, is holding out.
Kondo explained that a gentlemen's agreement which may or may not be legally binding gives the local government a veto over restarting the plant if safety concerns have not been addressed. (Kondo did not discuss rumors that the governor is holding out for an extension of Japan's high-speed bullet train lines to the remote prefecture as a condition of approving a Monju restart.) Kondo said that the ministers of Education and of Economy, Trade and Industry will meet with the governor to try to resolve the impasse.