The Philippine Online Chronicles

On 11 March 2011, the Sendai earthquake struck. It caused a tsunami to strike not just Japan, but tsunami alerts went off around the entire Pacific Ocean, including the United States West Coast. To put the magnitude of this earthquake into perspective, the Japanese coast moved 2.4 meters. Now, because of this incident the Fukushima Daichi nuclear power plant suffered what experts call, a station blackout, and what they are trying to stop is what they call, a core meltdown. We will try to explain things, without going deep into the physics.

(This will be an overtly simplistic explanation).

Big words right?

Let’s try to put things in perspective. We know the earthquake is the most powerful that Japan has ever experienced. We also know that since the world has been keeping records (the year 1900; that’s like a 110 years ago only), this is the fifth most powerful earthquake ever. So there could be more powerful earthquakes, we just don’t know because no records have been kept.

So OK, Fukushima Daichi is a Nuclear power plant. You could argue, what in all the tea in Tokyo were the Japanese thinking of putting a Nuclear plant, on their island, knowing that they are an Earthquake prone country?

Am I right?

Fukushima Daichi first came online on October 1970. And it started generating electricity on 26 March 1971. Last month (February 2011), Japanese nuclear energy regulators gave it another 10 years to operate.

See, Fukushima Daichi was designed to take on an 8.2 Earthquake. Can we hear a round of applause for Japanese engineering? The facility withstood against an 8.9 earthquake!

This is why the Japanese were confident. The technology can take it.

Wait a minute you say, it is melting down and you’re saying it held together?

The short version is: it didn’t collapse when the Earthquake struck. In fact, the reactors automatically went offline when the earthquake struck.

Engineers when they design something like this, they build it with backups, and those backups have a backup. This is called, redundancy. That’s how they designed Fukushima, and every other Nuclear plant. People take nuclear energy very seriously.

So what’s happening now?

Experts call it a station blackout. What this means is that the main power to the station is cut off. The backup power likewise goes offline.

In the case of Fukushima, the earthquake and the following tsunami made sure that a station blackout occurred. When the backup generators failed to kick in, the station switched to batteries, and the core, control rods went inside containment. Containment like where you keep the nuclear material.

Eight hours is supposed to be a whole lot of time. Long enough to bring power back on right? Well, it seemed that they did bring in some mobile generators, but according to one expert, the plugs didn’t fit.

So power goes offline.

The big concern is a core meltdown. This is the worst case scenario. The fuel melts, and it will melt through its own container because it really is super hot. It becomes something like lava. When it destroys its container, that’s the scary part.

What is happening at Fukushima is technically called, a “partial meltdown.” What this means, the fuel rods used at the plant become partially uncovered with water. As we explained they are normally covered with water.

Tokyo Electric Power Company (TEPCO) officials for example revealed that Fuel rods at Fukushima reactor 2 have partially melted.

Part of the design of a nuclear reactor, the fuel (uranium rods) are submerged in water. The water used on uranium btw is pure water, which is like distilled water, because this more or less stays radioactive-free, while dirt or salt water can become radioactive.

So anyway, when water descends below the fuel level, fuel heats up. It already is super hot in there, which is why water is constantly pumped in to begin with. The water is used to keep the temperature at a manageable level. So what’s important it to keep water in the area of the fuel. Water keeps it from overheating.

Now, ok, we heard stories of explosions and that the Japanese released the pressure from the facility and into the atmosphere. The controlled venting occurred to keep the pressure down.

It is like you’re heating water in a kettle. It whistles when it boils right? What happens when you put something to cover that whistle? So evaporated water is kept inside the kettle. The pressure will eventually become great, and if the kettle can’t hold on to that pressure, it blows up right?

So this is why there was a release, which is also about releasing some radiation into the environment. Experts are all on hand to measure the amount of radiation that was vented into atmosphere, to see it if posed threat to human health.

Radiation is constantly around us that has nothing to do with nuclear reactors, and nuclear power plants. And our human bodies naturally absorb them. There is however a level where we can safely absorb them, without suffering any sickness. This is why experts are monitoring the area around the plant, (and other Japanese sites). This is why the Japanese have issued iodine to keep their thyroid in check.

Why the explosion? Brave New Climate explained that,

“It is not entirely clear yet what has happened, but this is the likely scenario: The operators decided to vent the steam from the pressure vessel not directly into the environment, but into the space between the third containment and the reactor building (to give the radioactivity in the steam more time to subside). The problem is that at the high temperatures that the core had reached at this stage, water molecules can “disassociate” into oxygen and hydrogen – an explosive mixture. And it did explode, outside the third containment, damaging the reactor building around. It was that sort of explosion, but inside the pressure vessel (because it was badly designed and not managed properly by the operators) that lead to the explosion of Chernobyl. This was never a risk at Fukushima. The problem of hydrogen-oxygen formation is one of the biggies when you design a power plant (if you are not Soviet, that is), so the reactor is build and operated in a way it cannot happen inside the containment. It happened outside, which was not intended but a possible scenario and OK, because it did not pose a risk for the containment.”

This is why I am not afraid about Japan’s nuclear reactors, said that the explosion occurred outside a third containment where there is no radioactivity. This is the reactor building.

In order to prevent a core meltdown, the Japanese used sea water to cool the core. Ok, wait, we mentioned earlier that salt water is a bad idea. But the Japanese mixed Boric acid with the salt water, and this helped bring the core temperature down. This permanently ruined the reactor.

The Pentagon announced that the carrier Ronald Reagan, passed through a radioactive cloud from Japan. The result, crew members received a month’s worth of radiation in an hour, but this isn’t caused for alarm.

According to the International Atomic Energy Agency (IAEA), the world’s governing body on all things radioactive that everything is under control.

Stories of course will come out about the dangers of nuclear energy, and radiation. Nuclear is very dangerous, this is true. The men and women who design nuclear plants, who handle nuclear energy, and radiation are very serious people. Nuclear plants, anything radioactive for that matter is handled just as guns are handled by professionals. They handle it with care.

In the Philippines, the country routinely uses radioactive material. We use it to fight cancer. In some hospitals, doctors even embed radioactive material in a patient’s body to destroy cancer cells. There are facilities in the Philippines that use radiation to increase shelf life of food. We can also use it to kill fruit flies in our mangos.

The safety, and handling of nuclear material in the Philippines is strictly enforced by the Philippine Nuclear Research Institute (PNRI) from medical professionals to safety technicians. Design of cobalt bunkers in the Philippines for example are strictly enforced. Accounting where radioactive material in the Philippines is likewise enforced, just as strictly as the safety and training of personnel are.

The question whether or not Nuclear power is too dangerous to handle is a political question, not an engineering one. Fukushima survived the 2011 Sendai earthquake, and while the situation is extremely dangerous, the experts have it under control.

Image grab from NHK World.