Nuclear Crisis - Update

A former nuclear power plant designer has said Japan is facing an extremely grave crisis and called on the government to release more information, which he said was being suppressed.

Masashi Goto told a news conference in Tokyo that one of the reactors at the Fukushima-Daiichi plant was "highly unstable", and that if there was a meltdown the "consequences would be tremendous". He said such an event might be very likely indeed. So far, the government has said a meltdown would not lead to a sizeable leak of radioactive materials.

Mr Goto said the reactors at the Fukushima-Daiichi nuclear plant were suffering pressure build-ups way beyond that for which they were designed. There was a severe risk of an explosion, with radioactive material being strewn over a very wide area - beyond the 20km evacuation zone set up by the authorities - he added. Mr Goto calculated that because Reactor No 3 at Fukushima-Daiichi - where pressure is rising and there is a risk of an explosion - used a type of fuel known as Mox, a mixture of plutonium oxide and uranium oxide, the radioactive fallout from any meltdown might be twice as bad.

He accused the government of deliberately withholding vital information that would allow outside experts help solve the problems. "For example, there has not been enough information about the hydrogen being vented. We don't know how much was vented and how radioactive it was." He also described the use of sea water to cool the cores of the reactors at Fukushima-Daiichi as highly unusual and dangerous.

He described the worst-case scenario: "It is difficult to say, but that would be a core meltdown. If the rods fall and mix with water, the result would be an explosion of solid material like a volcano spreading radioactive material. Steam or a hydrogen explosion caused by the mix would spread radioactive waste more than 50km. Also, this would be multiplied. There are many reactors in the area so there would be many Chernobyls."

At the same time, Malcolm Crick, the secretary of the UN Scientific Committee on the Effects of Atomic Radiation, has told the Reuters news agency: "This is not a serious public health issue at the moment. It won't be anything like Chernobyl. There the reactor was operating at full power when it exploded and it had no containment."

Another Nuclear Plant Has a Problem:

A pump within the cooling system of one of the reactors at the Tokai nuclear power plant has stopped working, according to the Kyodo news agency. The plant is located in the Naka district of the central prefecture of Ibaraki, and is operated by the Japan Atomic Power Company.

The 1,100MW Tokai plant, about 120km (75 miles) north of Tokyo, was automatically shut down after Friday's earthquake.

Meanwhile, the Shinmoedake volcano in southern Japan has resumed eruptions of ash and rocks after a couple of weeks of inactivity, Japan's meteorological agency has said. It is unclear if the eruptions are linked to Friday's earthquake.

BBC