The discharge is expected to take place over 17 days.

TEPCO confirmed that the radioactive level of the treated water is below safety standards, based on its monitoring of nearby waters after the previous three discharges. A total of 23,351 tons of the treated water has been released into the sea during the previous three rounds from August to November 2023.

The company said it plans to release four more rounds of discharge from April 2024 to March 2025, releasing a total of 54,600 tons of treated waste water into the sea.

According to Japanese media, the level of tritium, a radionuclide, concentrated in the treated waste water to be released by TEPCO is estimated at 14,000 billion Becquerel (Bq), below the regulatory standard of 22,000 billion Bq per year.

On February 7, 1.5 tons (adjusted from initial estimates of 5.5 tons) of radioactive wastewater was leaked from the Fukushima nuclear power plant’s High Temperature Incinerator Building.

In October last year, there was also an incident where an employee of this power plant spilled liquid containing radioactive substances.