Japan plans to release more than 1 million tonnes of contaminated water from the Fukushima nuclear plant into the sea, according to the government.
Japan has argued the water, which will have been treated, is necessary to release in order to press ahead with the complex decommissioning of the plant after it was effectively destroyed by the 2011 earthquake and tsunami.
The first release of water will take place in about two years, giving plant operator Tokyo Electric Power (TEPCO) time to begin filtering the water to remove harmful isotopes, build infrastructure and acquire regulatory approval.
The move is not without its critics.
“This action is extremely irresponsible, and will seriously damage international public health and safety, and the vital interests of people in neighbouring countries,” China’s foreign ministry said in a statement on its website.
South Korea’s government summoned Japan’s ambassador to Seoul to protest at the move.
“The decision can never be accepted and would not only cause danger to the safety and maritime environment of neighbouring countries,” a senior official told a briefing after vice-ministers held an emergency meeting to discuss the issue.
“It was also made unilaterally without sufficient consultations with our country, which is the closest neighbour to Japan,” Koo said.
Nearly 1.3 million tonnes of contaminated water, or enough to fill about 500 Olympic-sized swimming pools, is stored in tanks at the plant at an annual cost of about 100 billion yen ($913 million).
“Releasing the … treated water is an unavoidable task to decommission the Fukushima Daiichi Nuclear Power Plant and reconstruct the Fukushima area,” Prime Minister Yoshihide Suga said of the process that will take decades to complete.
The decision comes some three months ahead of the postponed Tokyo Olympic Games, with some events to be held as close as 60 km (35 miles) from the wrecked plant. Former Japanese Minister Shinzo Abe in 2013 assured the International Olympics Committee in pitching for the games that Fukushima “will never do any damage to Tokyo.”
The utility company responsible for the action, TEPCO, plans to filter the contaminated water to remove isotopes, leaving only tritium, a radioactive isotope of hydrogen hard to separate from water.
TEPCO said it will then dilute the water until tritium levels fall below regulatory limits, before pumping it into the ocean.
The Japanese government It says similarly filtered water is routinely released from nuclear plants around the world and has been keen to stress the filtering and dilution processes. As an example, the Japanese government has requested that the term “contaminated” not be used in reporting, arguing it is misleading.