Sabtu, 12 Maret 2011

Nuclear Meltdown?

There is growing concern regarding several nuclear plants in Japan:

Explosion, radiation leakage rock Japan nuclear plant

Jiji news agency said there had been an explosion at the stricken 40-year-old Daichi 1 reactor and TV footage showed vapour rising from the plant, which lies 240 km (150 miles) north of Tokyo.

Pressure was building in reactors of two plants at Tokyo Electric Power Co 's Fukushima facility, located some 240 km (150 miles) north of Tokyo. At one of them, the Daiichi plant, pressure was set to released soon , which could result in a radiation leak, officials said.

TEPCO said it had lost ability to control pressure in some of the reactors at the Daini plant as it had with the Daiichi plant. Pressure wa s stable inside the reactors of the Daini plant but rising in the containment vessels, a spokesman said.


Radiation levels soaring at damaged nuclear plant, pressure out of control

It’s not a Three Mile Island situation yet, let alone a Chernobyl, and given the fact that the reactors are covered with containment vessels (which Chernobyl wasn’t), it’s unlikely to get quite that bad. But Dow Jones is now reporting that the local electric company says it’s “lost control over pressure in the reactors,” and stories on the wires an hour ago claimed that radiation levels in the control room at the plant have reached 1,000 times their normal level. And so one of the worst days in Japanese history may be about to turn worse still.

In a nutshell, the reactors are overheating because they can’t pump coolant into them. So massive was the quake that virtually all of the plant’s power sources are offline; no power means no pump means no coolant, which means the cores are going to get hotter and hotter.

As you’ll see below, they do have emergency diesel systems available to get some coolant in there, but it sounds like that may succeed only in slowing the pace of the overheating, not reversing it

Potentially, it may get so hot that it melts down; in the near term, the heat in the chamber will produce radioactive steam, which will have to be released into the atmosphere or else the chamber could blow.


And this:

3,000 people in a two-mile radius have already been evacuated and those who remain within a seven-mile radius have been told to stay indoors. Gu

Update: The emergency cooling system is running on battery power right now, and the batteries are running down. Once all the juice is gone, it’ll be only hours until meltdown.

Officials are now considering releasing some radiation to relieve pressure in the containment at the Daiichi plant and are also considering releasing pressure at Daini, signs that difficulties are mounting. Such a release has only occurred once in U.S. history, at Three Mile Island.

“(It’s) a sign that the Japanese are pulling out all the stops they can to prevent this accident from developing into a core melt and also prevent it from causing a breach of the containment (system) from the pressure that is building up inside the core because of excess heat,” said Mark Hibbs, a nuclear expert at the Carnegie Endowment for International Peace.

A horrifying quote from a nuclear waste specialist who spoke to ABC: “Given the large quantity of irradiated nuclear fuel in the pool, the radioactivity release could be worse than the Chernobyl nuclear reactor catastrophe of 25 years ago.”


Radiation Levels Surge Outside Two Nuclear Plants in Japan

Even Washington's blog weighs in on this one:

Japanese, Russian and Indonesian Volcanoes Erupt...5 Japanese Nuclear Reactors in Danger....1 is leaking and May Melt Down Within 24 Hours

Update: It's possible that a meltdown may already have occurred at one nuclear power plant. As AP wrote 4 minutes ago:

An official with Japan's nuclear safety commission says that a meltdown at nuclear power plant affected by the country's massive earthquake is possible.

Ryohei Shiomi said Saturday that officials were checking whether a meltdown had taken place at the Fukushima Dai-ichi power plant, which had lost cooling ability in the aftermath of Friday's powerful earthquake.

Japanese nuclear authorities said that there was a high possibility that nuclear fuel rods at a reactor at Tokyo Electric Power's Daiichi plant may be melting or have melted, Jiji news agency reported.

Experts have said that if the fuel rods have been damaged, it means that it could develop into a breach of the nuclear reactor vessel and the question then becomes one of how strong the containment structure around the vessel is and whether it has been undermined by the earthquake.

Two other Japanese nuclear reactors are now in trouble as well.

Coolant systems failed at three quake-stricken Japanese nuclear reactors Saturday, sending radiation seeping outside one and temperatures rising out of control at two others.


Japan quake causes emergencies at 5 nuke reactors

Japan declared states of emergency for five nuclear reactors at two power plants after the units lost cooling ability in the aftermath of Friday's powerful earthquake. Thousands of residents were evacuated as workers struggled to get the reactors under control to prevent meltdowns.


This situation will evolve rapidly one way or the other. This situation in Japan continues to get worse, and now volcanos have seemingly been triggered as well.

Birth pains. We're most definitely seeing an increased frequency and severity in such pains as we approach the final stages of the birthing process.

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