Progress in Efforts for Decommissioning

< Removal of spent fuel >

Removal of all 1,535 fuel assemblies from the spent fuel pool was completed at Unit 4 in December 2014 and the risk of discharge of radioactive materials caused by the breaking down of spent fuel due to failure to cool it down was significantly reduced.

At Unit 3, removal of fuel was commenced in April 2019 and removal work was continued steadily and safely, aiming to achieve completion within FY2020.

At present, preparations are being steadily progressed at Units 1 and 2 for clearance of rubble. From now on, preparatory work will be carried out while placing top priority on ensuring safety, such as through adopting new methods of installing large covers at working sites in order to further suppress scattering of dust.

 

< Removal of fuel debris >

The Mid- and Long-term Roadmap revised in December 2019 decides the method of removing fuel debris. The removal work will be commenced at Unit 2 first on a trial basis, and the scale will be sequentially expanded in stages.(Note 1)

Investigations of the inside of containment vessels by using robots that were developed based on cutting-edge technologies have been conducted so far. Efforts will be continued to develop technologies necessary for those investigations and fuel debris removal, and systems to confine radioactive materials.

 

(Note 1) Trial removal work may be delayed for around one year (initially scheduled to be commenced within 2021) due to delay in the development of relevant equipment caused by the spread of the COVID-19 infection.

• Included in this reference material on February 28, 2018
• Updated on March 31, 2021