Refurbishment and safety management of JMTR in extended showdown

Ide, Hiroshi  ; Hori, Naohiko ; Gorai, Shigeru; Kusunoki, Tsuyoshi 

Japan Materials Testing Reactor (JMTR) is a testing reactor dedicated to the irradiation tests of materials and fuels. The reactor type of the JMTR is light water moderated and cooled tank type. It achieved first criticality in 1968. Operation was started in 1970. The JMTR had been being operated for 38 years from first criticality to the JMTR No.165 cycle finished. The restart of the JMTR has been strongly requested from various users as the only irradiation testing reactor in Japan. Finally, Japan Atomic Energy Agency (JAEA) decided the refurbishment and restart of the JMTR in December 2006, and the refurbishment works was started from FY 2007. This report summarized JMTR refurbishment and safety management during reactor shutdown.