The logo of Tepco, a Japanese utility company that has been forced to ask for additional bailouts from the government to pay for expenses arising from its Fukushima nuclear power plant accident
The logo of Tepco, a Japanese utility company that operates Fukushima nuclear plant. Reuters

Japan is set to declare a leak of highly radioactive water at the damaged Fukushima Daiichi nuclear power plant a level 3 “serious incident,” the highest warning given out since the 2011 earthquake and tsunami.

According to the New York Times, Japan’s Nuclear Regulation Agency is likely to declare the radioactive leak a level 3 on the International Nuclear and Radiological Event Scale soon after confirming the rating with the Vienna’s International Atomic Energy Agency.

"The current situation is at the point where more surveillance won't be enough to keep the accidents from happening," Shunichi Tanaka, chairman of the authority, told the Times. "Our job is now to lower the risk of these accidents from becoming fatal."

Previously, Japan's Nuclear Regulation Authority rated the latest leak as a level 1 incident on the INES. INES rates nuclear incidents and accidents on a scale starting from ‘0’ depending on the safety significance of the incidents, with zero denoting the least level of danger.

When the Fukushima facility was hit in March 2011, it was termed a level 7 accident by INES -- one of the worst nuclear disasters since the Chernobyl accident in 1986 -- after a giant tsunami triggered by an earthquake ravaged the nuclear plant, and damaged its back-up generators and cooling system, leading to a meltdown of its reactors.

The Tokyo Electric Power Company (TEPCO) states that at least 300 tons of water with dangerously high levels of radiation has leaked from the storage tank. Radiation from the water could make a person who is within several feet seriously sick within hours, Reuters reported.

TEPCO said that its workers who were monitoring the storage tanks had failed to detect the leak earlier.

"We failed to discover the leak at an early stage and we need to review not only the tanks but also our monitoring system," a TEPCO official told Reuters.

The leak is a continuous one and workers at the power plant are transferring the water from the affected tank to a temporary storage facility.

“A puddle of approx. 3mx3mx1cm was found outside of the drain valve of the dike. Other than this puddle, there was another puddle of approx. 50cmx6mx1cm found outside of the dike… We started collecting water in the tank dike. Water was pumped up with a temporary pump to a temporary tank, and absorbent was placed inside the dike,” Tepco said in a statement.