According to National Geographic, as of last week there were about 330 workers at the plant, working in fifteen-minute shifts to keep from getting sick. NPR reports that:

So far, at least 15 of these workers have been injured by explosions. An additional 17 have suffered what the Japanese government called “deposition of radioactive material” to their faces. Two are missing.

How much radiation are they being exposed to? It’s hard to say. But an article in Nature News identifies that:

The [Japanese] government has increased the allowable dose for workers from 100 milli­sieverts per year to 250 millisieverts per year — five times the annual allowable dose for US radiation workers — to allow emergency operations to continue. This dose is considered by the US National Institutes of Health as the lower limit for the first symptoms of radiation sickness.

Millisieverts are the standard by which radiation is measured. For reference, National Geographic shares that:

…the average person receives about one to two millisieverts a year from natural sources in their environments, and one chest x-ray yields about 0.2 millisievert.

As the viral, must-see Nuclear Boy, states on YouTube, these workers are really “stepping up to the plate.” (The YouTube video explains the disaster very clearly through a stinky metaphor, in which the Fukushima workers are doctors taking turns caring for Nuclear Boy. Watch it, if you haven’t.)

Not only are they risking their lives, in the process, they are making excellent, life-saving decisions. From Nature News:

And already it is clear that decisions made in the initial 24 hours by the handful of operators in the control room probably averted a much greater nuclear catastrophe than the one that now faces Japan.

Fukushima Unit I Visualization by Nesnad/Wikimedia

Of the six reactors at the power plant, only three were operating at the time of the earthquake, and all three—Units 1, 2 and 3—are experiencing problems.  The problems didn’t stem from the shaking, but rather from the lack of power and water needed to cool down the reactors.

All three are boiling water reactors, and NPR describes how they work:

The nuclear fuel heats water, generating steam that then turns a turbine to create electricity. The water is also used to keep the nuclear rods cool.

Heat has built up in the last few days, causing two problems—overheating the water and melting the nuclear rods.

When the water is over heated, hydrogen is stripped out of the water. But hydrogen is highly combustible—that’s what caused the explosions in Unit 1 on Saturday and Unit 3 today.

The nuclear rods are generally covered in water, but when that level subsides, meltdown can occur. Scientific American explains the process:

If the water descends below the level of the fuel, then the temperature starts going up and the cladding bursts, releasing a lot of fission products. And eventually the core just starts slumping and melting.

Nature’s The Great Beyond blog reports today that:

According to a report on NHK world, the fuel rods inside unit 2 were “fully exposed” meaning that there was no water left in the core to cool them. This makes it pretty likely that unit 2 has now suffered serious damage to the core.

Seawater is being brought in to do the cooling work now, but it’s hard to judge how much damage has already been done. Again, from NPR:

There’s no way to know for sure that a partial meltdown has occurred, since you can’t get inside the steel reactor vessel, where the fuel is. But officials have found cesium-137 in the air. That’s evidence that radioactive fuel — which is supposed to be completely sealed in metal tubes inside the reactor — has been exposed to water or air. That suggests a fuel rod or rods have melted or have broken.

Radiation levels appear to be high in the area, but information seems to be limited, and perhaps is even being withheld, The Great Beyond reports. Recently touted as a future cleaner energy solution, what this all means for nuclear energy around the world seems to be on everyone’s minds today. From Science Daily:

Switzerland put on hold some approvals for nuclear power plants and Germany said it was scrapping a plan to extend the life of its nuclear power stations, raising questions over the future of the global nuclear industry. Taiwan’s state-run Taipower also said it was studying plans to cut nuclear power output.

(You can also read more about this debate in Reuters, the LA Times and reports of an online scare-hoax. The publicly owned television channel in Germany, Das Erste, also has a story on nuclear power plants on fault lines in California—particularly the Diablo Canyon Power Plant at Avila Beach.)

No doubt more information will come out as the day and week goes on—NPR and The Great Beyond seem to be great resources. Please share more resources or news below.

Image of Fukushima 1 reactor pre-explosion, KEI/Wikimedia

Up-to-date Information can be found here.

Videos, Animations and Images

In case you haven’t seen them—these are stunning and terrifying.

• -The devastating tsunami sweeping through the Miyagi Prefecture can be seen here and here.
• -Tokyo buildings swaying during the earthquake here.
• -A NOAA animation and image of the tsunami movement
• -Images and video of Santa Cruz harbor destruction.

Science Behind the Earthquake

Find out how earthquakes work from BoingBoing and how tsunamis are triggered far away from earthquake’s epicenter from Scientific American. The 80beats blog on Discover breaks down what happened and explains why it could have been worse. And the New York Times has an article about Japan’s strict building codes.

Tsunami in California

Why has Crescent City been so hard hit? Location, location, location, according to Time.

Supermoon?

The Daily Mail linked the full, close moon coming on March 19^th with this earthquake in tsunami. Baloney say scientists. Neil deGrasse Tyson tweeted, “Interviewed often today. Press wants to blame Japanese quake on cosmos. The Moon is innocent. Blame plate tectonics. Period.”

More:

• -How you can help.
• -Subscribe to USGS Earthquake Notification Service
• -The latest on California State Park closures.
• -Earthquake blog from UC Davis.

Add to the list, please!