The company is transfusing the water into a facility where it will be mixed with sea water, which will reduce the proportion of tritium there to the level that is 40 times lower than the maximum norm, the local broadcaster reported.
Another local news agency reported, citing TEPCO, that around 31,200 tonnes of water with a cumulative 5 trillion becquerels of tritium will be released in fiscal year 2023 (until March 31, 2024).
Earlier on Tuesday, Japanese Prime Minister Fumio Kishida said that the release of treated radioactive water from the Fukushima NPP into the sea will begin on August 24 if weather and sea conditions allow.
Japan initially planned to begin discharging water purified of all radionuclides except tritium into the ocean 0.6 miles from the station this spring. However, the deadline was pushed back to the summer of 2023 due to adverse weather conditions and other factors.
The Fukushima nuclear disaster occurred on March 11, 2011. The plant was severely damaged by a magnitude 9 earthquake in the Pacific Ocean. This triggered a massive tsunami that hit the plant and caused three nuclear reactors to melt down. The accident is considered the worst nuclear disaster since the Chernobyl accident in 1986 and has resulted in widespread contamination of local soil and water. The disaster left 22,200 people dead or missing.