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| Image: Livefreelivenatural.com |
The New York Times reports, “Thousands of workers and a small fleet of cranes are preparing for one of the latest efforts to avoid a deepening environmental disaster that has China and other neighbors increasingly worried: removing spent fuel rods from the damaged No. 4 reactor building and storing them in a safer place.” The Japan Times reports, “In November, Tepco plans to begin the delicate operation of removing spent fuel from Reactor No. 4 [with] radiation equivalent to 14,000 times the amount released by the Hiroshima atomic bomb. Removing its spent fuel, which contains deadly plutonium, is an urgent task. The consequences could be far more severe than any nuclear accident the world has ever seen. If a fuel rod is dropped, breaks, or becomes entangled while being removed, possible worst case scenarios include a big explosion, a meltdown in the pool, or a large nuclear fire. Any of these situations could lead to massive releases of deadly radionuclides into the atmosphere, putting much of Japan – including Tokyo and Yokohama – and even neighboring countries at serious risk.” Former United Nations advisor Akio Matsumura says removing the materials “an issue of human survival.” Mycle Schneider and Anthony Froggatt said in their World Nuclear Industry Status Report 2013, “Full release from the Unit-4 spent fuel pool, without any containment or control, could cause by far the most serious radiological disaster to date.”
The operator of the crippled Fukushima nuclear plant is preparing to remove more than 1,300 used fuel rod assemblies packed tightly together. The reason being, they need to be removed from a third floor of a building that is vulnerable to collapse should there be another earthquake. The procedure will take about a year. Each fuel rod weighs approximately 660 pounds and is 15 feet long. Spent fuel rods also contain plutonium, one of the most toxic substances in the universe.
The danger of this mission is very real. What was once done with a computer controlled process that memorized the exact locations of the rods, down to the millimeter, is now being done by humans with a very real danger and high risk that a rod can be dropped or broken or even gets too close to an adjacent fuel rod. If the 1,535 fuel rods in the spent fuel pool 100 feet above ground collapse, it will even affect the common spent fuel pool containing 6,375 fuel rods located 150 feet away from reactor 4. In both cases, they are not protected by a containment vessel. This would certainly cause a global catastrophe that would affect us for centuries. “The biggest risk of a meltdown crisis wasn’t the reactors themselves but the spent fuel pools sitting atop them, particularly the one above reactor 4, which still contains about 1,500 nuclear fuel assemblies. I would say the crisis opened a Pandora’s Box,” said Hiroshi Tasaka, a professor at Tama University who has a doctorate in nuclear engineering.
Spent fuel rods must be kept submerged under at least 20 feet of constantly circulating cold water for at least five years after being removed from the reactor core. Spent reactor fuel cannot be simply lifted into the air by a crane as if it were simple cargo. In order to prevent severe radiation exposure, risk of fire, and possible explosions, they must be transferred at all times in water and heavily shielded structures into dry casks.
An analogy presented to us by Arnie Gundersen, a veteran U.S. nuclear engineer and director of Fairewinds Energy Education who used to build fuel assemblies, wants us to look at this situation like a pack of cigarettes. If you pull a cigarette straight up, it will come out, but these racks have been distorted. Now, if you pull a cigarette straight out, it’s most likely to break and release radioactive cesium and other gases into the air. “I suspect we’ll have more airborne releases as they try to pull the fuel out. If they pull too hard, they’ll snap the fuel. I think the racks have been distorted, the fuel has overheated, the pool boiled, and the net effect is that it is likely some of the fuel will be stuck in there for a long, long time. The net effect is they have the bundles of fuel, the cigarettes in these racks, and as they pull them out, they are likely to snap a few. When you snap a nuclear fuel rod, that releases radioactivity again, so my guess is, its things like krypton-85, which is a gas, cesium will also be released, strontium will be released. They’ll probably have to evacuate the building for a couple of days. They’ll take that radioactive gas and they’ll send it up the stack, up into the air, because xenon can’t be scrubbed, it can’t be cleaned, so they’ll send that radioactive xenon up into the air and purge the building of all the radioactive gases and then go back in and try again,” Gundersen said.
Here is a video about the radiation leak and how much of an impact it has had on the Japanese people.
Source: livefreelivenatural.com
