Nuclear Reactors 24 - Japan's Monju Reactor

Nuclear Reactors 24 - Japan's Monju Reactor

      Japan is poor in conventional energy resources. It is dependent on coal, oil and natural gas imports for the majority of its power generation.  Nuclear power was seen as an alternative source of energy despite the fact that uranium fuel has to be imported.  One possible solution to that problem was the creation of a fast-breeder reactor program. The fast breeder reactor was going to recycle the spent fuel rods from the uranium reactors in order to create a mixed plutonium and uranium fuel called MOX for mixed oxide. Theoretically, this would extend the power generating capability of uranium by a factor of twenty five.

             The Monju fast breeder reactor is located on the Japanese coast in Tsuruga, Fukui Prefecture.  Construction was begun in 1983 and finished in 1991. The first critical reaction test of the reactor was in 1994. In December of 1995, severe vibrations in a coolant pipe cased a leak which spewed  hundreds of pounds of liquid sodium onto the floor of the building. The liquid sodium reacted with oxygen and moisture in the air and burst into flames. The room was filled with toxic fumes. The heat rose to several hundred degrees Centigrade which actually warped some of the steel superstructure of the building. Later several tons of solid sodium were found on the floor of the room where the fire broke out. The reactor was shut down because of the leak.

The incident became a scandal because the plant operators tried to hide it from the public. The Power Reactor and Development Corporation falsified reports of the accident and actually edited video tape to try to prevent details from leaking out. An investigator committed suicide in 1996. His family claimed that he was being pressured to lie about the results of his investigation.

In late 2000, the Japan Atomic Energy Agency announced that they intended to restart the Monju reactor. Law suits against the restart followed which eventually worked their way up to the Japanese Supreme Court. The Court ruled in 2005 that the reactor could be restarted. Due to radioactive decay in the original fuel during all the delays, by 2008 the plutionium-241content of the fuel had dropped by fifty percent. This made a restart impossible with that fuel so the reactor had to be refueled. The restart was delayed again because holes were discovered in the reactor’s auxiliary building.

Finally, in 2010 start up procedures and testing began. The reactor achieved criticality in May of 2010 and was going to undergo testing until 2013 before being connected to the grid. In August of 2010, a three ton fuel loading machine fell into the reactor vessel and the reactor was shut down again. The repairs to the plant cost over sixteen million dollars. An Agency official in charge of the repairs killed himself during the work.

The disaster at Fukushima in March of 2011 caused the Japanese government to reevaluate the entire nuclear energy program in Japan. Testing for the restart of Monju was halted. Another scandal broke out in May of this year when it was discovered that Japan Atomic Energy Agency did not check over ten thousand components in use at Monju. Apologies and excuses were offered along with the usual promise to take care of the problem immediately.

            The Monju project has cost almost ten billion dollars to date. The Japanese government recently announced that it was considering permanently closing the Monju plant. It would be far better for Japan to concentrate on alternative renewable energy sources such as wind, solar and geothermal which are all readily available in Japan than to keep throwing money down the nuclear rat hole.