The operator of the Fukushima nuclear plant has started releasing radioactive wastewater into the sea.
In a live video from a control room at the plant on Thursday, Tokyo Electric Power Company Holdings showed a staff member turn on a seawater pump, marking the beginning of the controversial project that is expected to last for decades.
Fishing groups in Japan have opposed the plan out of worry of damage to the reputation of their seafood. Groups in China and South Korea have also raised concerns.
But the Japanese government and plant operators say the water must be released to make room for the plant’s decommissioning and to prevent accidental leaks.
The treatment and dilution will make the wastewater safer than international standards and its environmental impact will be negligibly small, they said.
The release begins more than 12 years after the March 2011 nuclear meltdowns, caused by a massive earthquake and tsunami.
The pump that was activated sends the first batch of the diluted, treated water from a mixing pool to a secondary pool, where the water is then discharged into the ocean through an undersea tunnel.
The water is collected and partly recycled as cooling water after treatment, with the rest stored in around 1,000 tanks, which are already filled to 98% of their 1.37-million-ton capacity.
Those tanks, which cover much of the plant complex, must be freed up to build the new facilities needed for the decommissioning process, officials said.