A view of Fukushima nuclear power plant
Source: Press TV
Japan has been warned against plans to flood a damaged reactor containment vessel at the Fukushima Daiichi nuclear plant.
Experts say flooding a reactor whose pressure vessel has been leaked might cause a potentially dangerous radiation leak in the plant
In the No.1 reactor, uranium fuel rods partially melted after they were fully exposed during the 11 March quake and tsunami, and keeping the leaked fuel cool is going to be very difficult, the facility's operator Tokyo Electric Power Co. (TEPCO) said.
Japan's Nuclear and Industrial Safety Agency said it believed partially melted fuel had fallen to the bottom of the pressure vessel, which holds the reactor core together, and may have leaked into its concrete base, known as the dry well.
Greenpeace has urged TEPCO to abandon plans to flood the container with water, given the likelihood that melted fuel has damaged it.
Shaun Burnie, nuclear adviser to Greenpeace Germany, said, "Flooding a reactor that has fuel [that has fallen] through the pressure vessel is not a good idea."
In April, the Japanese agency raised the severity level of the situation at Fukushima from 5 to 7 -- the worst on an international scale.
According to the agency, the amount of radiation emissions at the Fukushima plant was equivalent to 10 percent of that in the Chernobyl disaster in 1986.
A destructive 9.0-magnitude earthquake and an ensuing tsunami struck Japan's northern coasts on March 11, setting off a nuclear crisis by knocking out power to cooling systems of reactors at the Fukushima plant and causing radioactive leaks.
Engineers are pumping water into the reactors to cool them as they work to restore the damaged cooling systems.
TEPCO has said that it may take up to nine months to achieve a cold shut-down at the plant.