As we approach the one-year anniversary of the devastating earthquake and tsunami that destroyed parts of Japan, we look back to what happened and what was learned.
One year ago, Japan experienced a 9.0 magnitude earthquake, right off the coast, a 46-foot tidal wave, a broken and drowned nuclear plant and more than 20,000 of her citizens killed. Whole towns were reduced to driftwood, or washed out to sea all together. Many were never found.
Three nuclear reactors suffered total meltdowns, meaning that the fuel rods got so hot they melted into a blob of intensely radioactive metal in the bottom of the reactors. Then they leaked.
There was no way to put these back together again after that. It would be easier to fix a car after it’s been crushed – now, make that car radioactive, so you have to fix it with really long tools from inside a lead room a mile away – you get the idea.
But the reactors are stable, which is a euphemism for no nuclear explosion or huge release of radiation is expected. It took quite a while to get to where we could even say that.
But what a mess.
Some of the radiation already took care of itself. Radioactive iodine was initially quite high, but with an eight-day half-life, it is virtually gone. Five half-lives is a general estimate of the time required to make something go away (97% gone).
But there is still plenty of radioactive cesium, and with a 30-year half-life, it will take generations to wait out this stuff. Where is this radiation? Everywhere dust can settle, or get blown, or tracked.
There is more radiation on the outside, than on the inside, assuming you closed your windows. It is in the plants, the first couple inches of the ground and on every surface in sight. Nobody is entirely sure how to even clean it up.
The best you can hope for is to sweep up most of the radiation into one place, then bury it, real deep. You can’t neutralize the stuff. Hose it off your roof and now it’s in the water. Don’t even think about firing up your dust blower. So you scrape off the top 2 inches of dirt, scrub everything in site, and package up all the scrub water, dirt, rags, cleaning implements, and everything you couldn’t clean, and cart it off.
To where you ask?
Really good question-they are still working on that one. One house generated 60 cubic yards of contaminated material from just one clean up operation. And consider that about 88,000 people were displaced from the evacuation zone – that is a lot of property to clean up.
Until the whole area is cleaned, the radiation contamination will frequently redistribute itself. The radiation level will gradually drop in the affected communities, partly due to clean up efforts, but also do the averaging of radiation over a wider and wider area.
My organic chemistry professor used to say: “the solution to pollution is dilution.” Much of the cleanup will be dilution of the radiation into the world at large. It is estimated that it will take three decades to clean up the area. The plant itself cannot be rehabilitated.
The other alternative is the Chernobyl solution, where they drew a 20-mile circle and kept everyone out – forever. Japan is a little too densely settled for this answer.
So far there have been no deaths reported from radiation exposure in the accident. People just didn’t receive anywhere near lethal doses of radiation. Radiation in lower doses takes years to do its work.
Those who study such situations expect 1,000 additional cancer deaths in Japan from the Fukushima Nuclear accident. These 1,000 would occur in a country of 127 million people, spread out over the next 100 years. (For comparative purposes, Japan looses 5000 people per year in auto crashes.)
Two more reactors were planned to be built at the Fukushima plant in the next three years.
The world’s attention was captivated by this nuclear disaster. The worst imaginable happened, a triple meltdown. Japan is cleaning up the mess, and will rise from the ashes, again.