The decision to close the facility, announced on Monday, comes after stricter regulatory standards established following the 2011 Fukushima nuclear disaster.
The cost of revamping the Tokai plant to meet the new standards has been estimated at over 900 million dollars, masking it too expensive to maintain.
The plant extracts uranium and plutonium from spent nuclear fuel. It has processed about 1,140 tons of spent fuel since operations began in 1977.
Authorities say the transfer of the plant’s functions to a reprocessing plant in Rokkasho Village, Aomori Prefecture, is almost complete.
The Tokai facility was expected to treat spent fuel from the Monju fast-breeder reactor in Fukui Prefecture, so its closure may negatively impact the government’s policy to reuse spent nuclear fuel.