Japan had started on August 24 to release the water used to cool the Fukushima reactors that collapsed after the 2011 tsunami.
During the first discharge, 7,800 tons of wastewater were washed into the sea. In total, almost 1.34 million tons of wastewater is discharged into the sea in stages, an amount equivalent to 500 Olympic swimming pools. According to Tepco, all but tritium has been filtered from the water. Tritium is difficult to separate from water, but according to Tepco and the United Nations Atomic Energy Agency (IAEA), it is only present in wastewater in harmless amounts.
Yet China does not trust the discharges. The country accuses Japan of using the sea as a ‘sewer’. In response, China imposed an import ban on Japanese seafood after the first spill. That ban ended on September 11. Russia is also considering such an import ban. There were protests in South Korea against the discharges in August.
It will take decades for all the wastewater to be discharged into the sea. Then work can begin to remove the dangerous radioactive fuel and debris from the destroyed reactors.