Japan will dump more than a million tonnes of contaminated water from the Fukushima Daiichi nuclear power plant in the Pacific, a move condemned by environmentalists, fishermen and neighboring countries.
Tokyo Electric, the operator of the plant, will build equipment to dilute and release water, which has accumulated since three reactors melted in the 2011 tsunami that submerged the facility. Releases will begin in about two years, subject to final approval by nuclear regulators.
The decision – taken after years of public consultation and disputes of expert committees – risked rekindling some of the trauma of the nuclear accident and deepening its legacy of pollution.
But Japanese officials argued that there was no practical alternative to releasing the water because the storage space was exhausted. They add that there was no risk to human health and that the operation of nuclear power plants around the world release similar water everyday.
“By downgrading Fukushima Daiichi, we cannot avoid the problem of sewage,” Prime Minister Yoshihide Suga said after a meeting of ministers and political experts in Tokyo.
“Therefore, based on an approach that clearly exceeds safety standards and a careful plan to avoid reputational damage, we have found it pragmatic to discharge water into the ocean.”
the Fukushima reactors melted in March 2011, after a devastating tsunami destroyed their cooling systems. The water subsequently used to cool the reactors, as well as the groundwater flowing into the site, was contaminated with radioactive nuclides.
The contaminated water has been treated with an elaborate filtration system to remove most of the radioactive material. However, there is no practical way to filter out tritium, a radioactive isotope of hydrogen, the lightest element on the periodic table.
Tritium has a half-life of 12.3 years, the time it takes for half of the initial radioactivity to decay. Radiation can be hazardous to health, but everyone is exposed to a certain amount of background radiation, with higher doses during long-distance flight or an x-ray.
Japanese government claims radiation dose from Fukushima water is no more than 1/1000 of natural exposure, even though everything was released in one year.
The government has considered several alternatives, including evaporating water from the atmosphere or injecting it into underground reservoirs. But experts argued that diluting the water and slowly releasing it back into the ocean was the only viable choice.
“We will dilute the tritium to one-fortieth of the household standard and one-seventh of the World Health Organization standard for drinking water,” Suga said. He said the process would be fully open for inspection by the International Atomic Energy Agency.
Even if water will eventually be diluted in the wider Pacific, the Japanese fishing industry feared further damage to its reputation. Some countries maintain Japanese fish ban and other foods imposed after the Fukushima disaster.
“This decision is extremely regrettable and we do not accept it at all,” said Hiroshi Kishi, president of the National Federation of Fisheries Cooperatives. “We hereby register our strong objections.”
Environmentalists said Japan ignored the option of storing water indefinitely and took the cheapest approach of dumping it into the ocean. “The government has made the totally unwarranted decision to deliberately contaminate the Pacific Ocean with radioactive waste,” said Kazue Suzuki, an activist for Greenpeace Japan.
South Korea expressed “deep regret,” but the United States cautiously endorsed Japan’s approach.
“Japan has weighed options and effects, been transparent about its decision and appears to have taken an approach consistent with globally accepted nuclear safety standards,” the US State Department said.