Present status of dissembling of large fusion experimental device JT-60

Ikeda, Yoshitaka; Okano, Fuminori; Hanada, Masaya; Sakasai, Akira; Miya, Naoyuki; Watanabe, Takashi*; Daigo, Yasuhiko*; Hosogane, Nobuyuki*; Aoto, Mitsuo*

JT-60, to which the Radiation Hazard Prevention Act is applied, stopped its operation in October 2008 after 18 years deuterium operation since 1991. JT-60 will be upgraded to JT-60SA with superconducting magnet coils, which is the Satellite Tokamak Program under the EU-Japan collaboration, so as to demonstrate the high-beta long-pulse plasma operation. To establish this new device, the existing JT-60 facilities such as magnetic coils, vacuum vessel, basement, diagnostics and heating system. The disassembly of JT-60 is featured by the radiactivation of all components due to neutron from the D-D reaction, and thus, one of the main issues is to manage the physical control of the radiated material for the application of clearance regulation. The disassembly has started since 2009 and will complete by the autumn of 2012. Then a new JT-60SA basement, which will be shipped from EU, will be installed within March 2013.