Nuclear mattersOperator of shut-down Monju fast reactor seeks resumption of operations

Published 24 February 2010

Japan’s only breeder reactor was shut down in 1995 after sodium coolant leak; the reactor’s operator now seeks to restart the reactor, saying that a vast remodeling effort would prevent a similar accident in the fufutre; critics are no so sure, pointing to glitches affecting the reactor’s leak detector and other defects which have caused its restart to be put off four times since the coolant was infused again in May 2007

 The operator of the Monju fast-breeder reactor in Tsuruga, Fukui Prefecture, asked the prefectural government Tuesday to start talks on restarting possibly by the end of March the prototype reactor, which has been suspended since a 1995 sodium coolant leak.

The Mainichi Daily News reports that the Japan Atomic Energy Agency filed the request a day after the central government endorsed restarting the reactor — the only breeder reactor in Japan — moving to the final stage of winning local consent for resumption of fast-breeder development, a project in limbo for some fourteen years despite being favored in Japan’s nuclear policy.
The prefectural and city governments have yet to decide whether to give the go-ahead as they want reassurance on the reactor’s quake safety, keeping a close eye on the national government’s verification efforts since 2008 and discussions among experts.
To prevent and be better prepared for a possible sodium leak, the Monju has undergone a large remodeling of facilities, but glitches affecting its leak detector and other defects have caused its restart to be put off four times since the coolant was infused again in May 2007.
Critics have also raised concerns about the danger of using sodium, which deflagrates in the air, as a coolant and about the deterioration of facilities that have been unused for a prolonged period.

The JAEA, an independent national corporation, is required under a safety agreement it struck with each of the local governments to hold discussions with them before restarting the Monju reactor.