Containment Breach in Unit 2 at 6:10 AM – Japanese Time

On By southwerkIn business ethics

I’m not an engineer but there was a massive explosion, the Japanese government reported damage to the container shielding the reactor, there was a sudden spike in radiation (spiked after the explosion to 8,217 microsieverts an hour from 1,941 about 40 minutes earlier), water started pumping in faster than it would if the container were sealed (The U.S. official said water being pumped in is disappearing faster than it would if it only were caused by evaporation) and Japan began urgently requesting help from American and UN experts. Further, the Japanese officials were giving out varying information at different times to different people, that tells me something happened they couldn’t coordinate for a while. All this makes me believe there has been a breach in the containment vessel.

From the BBC –

The blast occurred at reactor 2 at the Fukushima Daiichi plant, which engineers had been trying to stabilise after two other reactors exploded.

The protective chamber around the radioactive core of reactor 2 has been damaged and radiation levels near the plant have risen, officials say.

From The Telegraph –

“There was a huge explosion” between 6:00 am (2100 GMT Monday) and 6:15 am at the number-two reactor of Fukushima No.1 nuclear power plant, a Tokyo Electric Power Co (TEPCO) spokesman said.

The government also reported apparent damage to part of the container shielding the same reactor at Fukushima 250 kilometres (155 miles) northeast of Tokyo, although it was unclear whether this resulted from the blast.

Chief Cabinet Secretary Yukio Edano told reporters the suppression pool of the number-two nuclear reactor appeared to have been damaged.

This is the bottom part of the container, which holds water used to cool it down and control air pressure inside.

From further down –

The Fukushima crisis now rates as a more serious accident than the partial meltdown at Three Mile Island in the US in 1979, and is second only to the 1986 Chernobyl disaster, according to the French nuclear safety authority. After insisting for three days that the situation was under control, Japan urgently appealed to US and UN nuclear experts for technical help on preventing white-hot fuel rods melting.

From ABC News –

The U.S. official said water being pumped in is disappearing faster than it would if it only were caused by evaporation, which suggests there may be a leak in the reactor’s containment vessel. But, the official said, it also could be that there is so much pressure inside the reactor that it is hard to pump in water.

A government official said that though the level of radiation rose around the reactor, there was no danger.

“The radioactive level near unit 2 has gone up, but at this juncture, the level is not judged to be immediately harmful to human bodies,” said Noriyuki Shikata, a spokesman in the prime minister’s office.

But Japanese news agency NHK reported that the radiation levels at the front gate of the Daiichi plant were so high that a person would receive more in one hour than they would receive naturally in an entire year.

From the New York Times –

This explosion, reported to have occurred at 6:14 a.m., happened in the “pressure suppression room” in the cooling area of the reactor and inflicted some degree of damage on the pool of water used to cool the reactor, officials of Tokyo Electric Power said. But they did not say whether or not the incident had impacted the integrity of the steel containment structure that shields the nuclear fuel.

Radiation levels around plant spiked after the explosion to 8,217 microsieverts an hour from 1,941 about 40 minutes earlier, the company said. Some emergency workers there were evacuated, though the levels would have to rise far higher to pose an immediate threat to health, officials said.

Any damage to the steel containment vessel of a nuclear reactor is considered critical because it raises the prospect of an uncontrolled release of radioactive material and full meltdown of the nuclear fuel inside. To date, even during the four-day crisis in Japan that amounts to the worst nuclear accident since Chernobyl, workers had managed to avoid a breach of a containment vessel and had limited releases of radioactive steam to relatively low levels.