TOKYO (Kyodo) -- Japan's Nuclear Regulation Authority on Wednesday endorsed a plan to discharge treated water stored at the crippled Fukushima Daiichi nuclear power plant into the sea.
The plan to release the low-level radioactive water starting around next spring will be officially approved after the regulator hears submissions from the public.
The plant's operator, Tokyo Electric Power Co. Holdings, will need to gain consent from municipalities hosting the power complex to start construction of the water discharge facilities.
Local fishery groups remain opposed to the plan over concern about reputational damage to their industry and consumer fears about the safety of the fish they catch.
The water, treated through an advanced liquid processing system that removes radionuclides except for tritium, will be diluted with seawater to one-fortieth of the concentration permitted under Japanese safety standards and released 1 km off the power plant via an underwater pipeline, according to the plan.
After the 2011 nuclear accident triggered by a massive earthquake and tsunami, water that has become contaminated after being pumped in to cool melted reactor fuel has been accumulating at the complex, also mixing with rainwater and groundwater at the site.
In addition to the local fishing communities, China and South Korea have expressed concerns and opposition to the planned water discharge.
TEPCO applied for an evaluation of the plan by the NRA in December. Through a total of 13 review meetings, the watchdog evaluated the function of the diluting facility, as well as a method of suspending the discharge of treated water when an unusual situation is detected, and measures against earthquakes and tsunamis, among others.
The NRA concluded the water discharge will help the operator secure space for facilities needed for future decommissioning work and lower overall risks to the Fukushima plant.
NRA Chairman Toyoshi Fuketa asked TEPCO to do its utmost to ensure there are no incidents at the planned water discharge facilities.