TOKYO -- Japan's cabinet and government officials on Tuesday decided to release treated wastewater into the ocean from the Fukushima Daiichi nuclear plant at a meeting to discuss the decommissioning of the crippled facility.
Experts have deemed that the water that contains tritium, a radioactive form of hydrogen, is scientifically safe. While other nuclear plants in Japan and elsewhere release the same kind of water into the sea, it took ten years to make the decision after the meltdown triggered by a magnitude 9.0 earthquake on March 11, 2011.
"We believe the decision will allow the decommissioning of the plant to move forward safely and steadily," Tomoaki Kobayakawa, president of the plant's operator, Tokyo Electric Power Company Holdings Inc. (TEPCO), told reporters after the meeting. "The site is now covered with tanks [for storing treated water], and we will be removing more difficult debris [or molten fuel]."
TEPCO will now lay out a policy for releasing the water. Japan's Nuclear Regulation Authority (NRA) is working on procedures for the release of radioactive materials, and the actual discharge will happen after piping and other facilities are installed. The process is expected to take two years.
The meltdown resulted in water being contaminated with high levels of radioactive materials. TEPCO has used specialized equipment to remove major radioactive substances, but the treated water still contains tritium. While water containing tritium is slightly heavier than regular water, they are almost indistinguishable. Tritium is also extremely hard to separate from the water with current technology.
Japan's regulations allow water containing 60,000 becquerels of tritium per liter to be released from ordinary nuclear facilities into the ocean. That is based on recommendations from the International Commission on Radiological Protection (ICRP), which say that the radiation dosage should be limited to 1 millisievert per year.
Even consuming two liters of water containing tritium a day would be well below the level of radiation exposure that could affect a person's health. When TEPCO releases treated water, it is diluted more than 100-fold using seawater, ensuring contains fewer than 1,500 becquerels of tritium. That is one-fortieth of the national standard.
Every country has different standards for tritium. The upper limit for drinking water in Australia, for example, is 76,000 becquerels per liter. The World Health Organization recommends a maximum of 10,000 becquerels, and Russia limits it to 7,000. In some countries the standards for drinking water are looser than Japan's regulations require for discharge into the ocean.
At nuclear and reprocessing plants in Japan and elsewhere, organizations such as power companies dilute tritium water with seawater before release into the ocean to ensure it meets national standards.
According to the Ministry of Economy, Trade and Industry, 860 trillion becquerels of tritium are stored in the tanks at the Fukushima plant -- equivalent to the amount of tritium released by South Korea's Wolseong Nuclear Power Plant over six to seven years. A reprocessing plant in France would release that amount in less than a year. No environmental impact has been confirmed in those countries.
Tritium is also found naturally in the human body and in the environment because of the radiation that blankets Earth from space. The environmental impact of discharging the treated water into the ocean is considered negligible. In February 2020, International Atomic Energy Agency Director General Rafael Grossi noted that the discharge of the treated water was based on scientific analysis, and it would not affect the environment.
China and South Korea also release tritium water into the ocean. However, China, Hong Kong, Macao, South Korea, Taiwan and the U.S. have stopped imports of food produced in some prefectures in the Tohoku and Kanto regions of Japan, both near the Fukushima plant.
The Japanese government has stated there is no scientific basis for imposing import restrictions, and it has asked all countries that restrict shipments to end the practice. However, 54 countries introduced import restrictions after the nuclear accident, and 15 of them still have some measures in place. The restrictions range from inspection certification requirements to full suspensions.
Concerns domestically and abroad -- and the reason it has taken a decade to decide to release treated water that has been scientifically proven to be safe -- stem from distrust in TEPCO over its procedures for nuclear power plants. The government has also been slow to act and generally left matters to the utility.
Immediately after the 2011 accident, contaminated water containing more radioactive material than permitted leaked into the sea on several occasions.
In 2013, South Korea imposed a ban on the import of marine products after there was a one-month delay making a public announcement that contaminated water had leaked into the sea. In July 2017, Takashi Kawamura, the then chairman of TEPCO, reportedly said that "the decision [to release the treated water into the sea] has already been made."
The National Federation of Japan Fisheries Cooperatives protested, calling the move "an act of betrayal to fishermen and the public." The minister of reconstruction at the time, Masayoshi Yoshino, who was also elected from Fukushima, expressed his opposition to the release of the wastewater, and TEPCO was forced to shelve the issue.
The issue was taken up by a study group at METI. The situation may have turned out differently if TEPCO and the government had been more conscientious in gaining the understanding of relevant parties and sharing information about the scientific safety of the release.
Many who visit the site of the reactor are surprised by the many huge, cylindrical tanks that TEPCO uses to store the water created on-site. As of March there were 1,061 -- all lined up on the south side of the plant, making it difficult to secure the space needed for further decommissioning work.
The decommissioning will take 30 to 40 years. One of the key issues to be addressed is the removal of fuel debris that melted and has since solidified. This debris is highly radioactive, and it must be stored under stringent conditions to ensure workers' safety and prevent leaks.
According to TEPCO's plan, 60,000 square meters of land is needed for a temporary storage facility for these materials. The government and TEPCO plan to reduce the number of tanks to free up more space, but there will not be an immediate impact because the contents of the tanks will be released into the ocean over a long period of time.
Already this year, there have been a series of scandals including the failure of seismographs at the Fukushima plant, and inadequate protection from nuclear materials at the Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture.
Hiroshi Kishi, chairman of the Federation of Fisheries Cooperatives, which opposes the plan to release the treated water, said last week that he has "very strong concerns about the safety assurances" of TEPCO.
The process of discharging the water is expected to continue for about 30 years. For TEPCO to continue to deal with the treated water, fight negative rumors and gain the understanding of fishermen and others, it is important for the company to dispel the distrust it faces in Japan and abroad. It will also be important for the government, as a shareholder in TEPCO, to take the lead in such reforms.