Atomic Reality

I’ve been watching the news about the Japanese reactor crisis and I have questions.

We’ve been told this reactor crisis was caused when electric power to the nuclear plant was disrupted by the quake and tsunami. That meant the plant’s cooling pumps couldn’t operate. The plant had backup diesel generators, but they were knocked out by the tsunami. The plant had backup batteries, too, but batteries (assuming the quake and tsunami didn’t destroy them) only last so long before they run down.

What I don’t understand is this: the nuclear plant generates electricity, so why does it need outside electricity to run its cooling pumps? I would expect a nuclear plant to be able to operate even if it were on an island. Or a ship. Or a submarine. What kind of nuclear plant design requires an outside supply of electricity, and if that supply is cut off the plant goes out of control? And if that isn’t a bad enough idea, put the plant on a seacoast near a geological fault line on the Pacific Ring of Fire where earthquakes are frequent. And let’s not forget there’s a reason “tsunami” is a Japanese word.

Currently the reactor, or the spent fuel rods, or both, are in partial meltdown, or full meltdown, or stable, depending on who is reporting the news. But before you run and buy iodide tablets, let’s remember a little history. It has been only a few decades since the United States and the Soviet Union were detonating atom bombs above ground on a regular basis. You’re worried about a little radioactive steam from a nuclear plant on the other side of the Pacific Ocean? Think about living in Nevada with atom bombs being detonated at the Nevada Test Site only 65 miles northwest of Las Vegas. You could see the mushroom cloud for almost 100 miles in every direction, including Las Vegas. In fact, it was a tourist attraction. People went to Las Vegas to see the distant mushroom cloud of an atomic test. Yes, we had strontium-90 in our bones and we liked it!

Or maybe we didn’t like it. Because in July, 1962, the US detonated its last above-ground bomb then switched to underground testing of atom bombs. There were 828 underground atomic tests in Nevada, of which 62 involved multiple, simultaneous detonations. One third of the underground atom bomb tests were detonated directly into an aquifer. Radioactivity in the ground water there reaches millions of picocuries per liter. The federal standard for drinking water is 20 picocuries per liter.

In 1997, the National Cancer Institute determined that above-ground atomic testing had spread enough iodine-131 across the US to produce 10,000 to 75,000 cases of thyroid cancer.

Strontium-90 has a half life of 28 years. Cesium-137 has a half life of 30 years. There are numerous other products of nuclear fission. These elements were carried through the air and deposited on the ground when it rained. They are still in the ground and are absorbed by plants. It will be several hundred years before they decay to a low level of radioactivity. We don’t live in a pristine and pure environment.

There are three elements that can be used to produce energy in a fission reactor: uranium, plutonium, and thorium (Th-232). Thorium is 4 – 5 times more abundant than all uranium isotopes combined. The US has enough thorium to power the country at its present energy level for over 1,000 years. With a liquid-fuel cycle (e.g., Molten Salt Reactor), there is no possibility of a meltdown, it requires no emergency cooling system, it does not produce weapons grade by-products, and it will burn up high-level waste and nuclear stockpiles.

So why don’t we build thorium reactors instead of uranium reactors? The answer is money. Thorium reactors require further development to be commercialized whereas we already know how to build uranium reactors. However, India is developing a 300 MW thorium-based reactor and plans to generate 30% of its electricity through thorium-based reactors by 2050. And this year China announced it "has initiated a research and development project in thorium molten-salt reactor technology.”

Coal power in the US accounts for 45% of the country’s electricity production, but deaths and diseases caused by breathing coal pollutants cost the US $160 billion annually. The US invented atomic weapons with the Manhattan project and put men on the moon with the Apollo program. A similar national push for thorium-based reactors could end our dependence on fossil fuels for electricity generation within a decade, and put us much closer to our goal of energy independence.