With the total amount of water to reach 11,500 tons, including contaminated groundwater from near the No. 5 and No. 6 reactors, the government said the disposal was unavoidable in order to secure safety. The level of radioactive substances in the water is up to 500 times the legal limit permitted for release in the environment.
The government's nuclear agency said the disposal will pose ''no major health risk'' and experts say that the radioactive materials are likely to be diluted in the sea, but it remains uncertain how the marine environment will be affected when taking into account the impact of highly radioactive water already leaking into the sea from the plant located on the coast of Fukushima Prefecture.
The utility known as TEPCO used colored powder Monday morning to determine how the highly radioactive water, believed to originate from the No. 2 reactor, made its way into the sea. But the Nuclear and Industrial Safety Agency said that it was not able to confirm the route of flow.