Local residents and environmental groups have condemned a plan to release radioactive tritium from the crippled Fukushima nuclear plant into the Pacific Ocean.
Officials of Tokyo Electric Power Co., the operator of the plant, say tritium poses little risk to human health and is quickly diluted by the ocean.
In an interview with local media, Takashi Kawamura, chairman of TEPCO, said: "The decision has already been made." He added, however, that the utility is waiting for approval from the Japanese government before going ahead with the plan and is seeking the understanding of local residents.
The tritium is building up in water that has been used to cool three reactors that suffered fuel melt-downs after cooling equipment was destroyed in the magnitude 9 earthquake and tsunami that struck north-east Japan in March 2011.