The government plans to release into the sea treated radioactive water from the Fukushima No. 1 nuclear power plant crippled by a powerful earthquake and tsunami in 2011 amid concerns over the environmental impact, sources close to the matter said Thursday.
An official decision may be made as early as this month and will put an end to seven years of debate over how to dispose of the water used to cool the power station that suffered core meltdowns in the disasters.
Earlier this year, a government subcommittee reported that releasing the water into the sea or evaporating it are "realistic options."
Local fishers and residents have been opposed to the release into the sea due to fears consumers would shun seafood caught nearby. South Korea, which currently bans imports of seafood from the area, has also repeatedly voiced concerns about the environmental impact.
Hiroshi Kishi, president of JF Zengyoren, a nationwide federation of fisheries cooperatives, expressed opposition to releasing the water into the sea in a meeting with Chief Cabinet Secretary Katsunobu Kato on Thursday.
The government will set up a panel to take measures to address such fears with Fukushima government officials and the local fisheries industry, the sources said.
As releasing the water into the sea requires construction work and an assessment by the Nuclear Regulation Authority, it would likely take around two years for the discharge to start, they said.
The water has been treated using an advanced liquid processing system, or ALPS, to remove most contaminants other than relatively less toxic tritium and is stored in tanks on the facility's premises. However, space is expected to run out by the summer of 2022, with the volume of contaminated water increasing by about 170 tons per day.
As of September this year, the stored water totaled 1.23 million tons, filling up 1,044 tanks.
Last month, Prime Minister Yoshihide Suga said the government wants "to make a decision as soon as possible" on how to deal with the water.
The International Atomic Energy Agency's Director General Rafael Grossi said during his visit to the plant in February that the release of the contaminated water into the sea meets global standards of practice in the industry.
This is a common way to release water at nuclear power plants across the globe, even when they are not in emergency situations, he said at the time.
But widespread concerns remain, with many countries and regions still restricting imports of Japanese agricultural and fishery products in the wake of the 2011 disaster.
Meanwhile, Tokyo Electric Power Company Holdings Inc. said Thursday that radioactive substances other than tritium in treated water at the Fukushima No. 1 nuclear power plant were reduced to levels below national standards through secondary treatment work.
Tepco has been conducting the additional clarification process at the meltdown-hit plant since September to test the performance of ALPS. Tritium, however, cannot be removed by any existing systems.
According to Tepco, some 70% of all the treated water stored at the power plant contained radioactive substances above the standards.
The levels fell below the limits after some 1,000 tons of treated water containing radioactive substances at levels 2,200 times the national standards were processed through the ALPS equipment, the company said.
Tepco said that it will continue to conduct the secondary treatment process on treated water stored at the power plant to bring down radioactive substances to levels below the standards.