Tuesday, April 10, 2012

Nuclear Radioactive Threat From Fukushima Spent Fuel Rods


Japan’s former Ambassador to Switzerland, Mr. Mitsuhei Murata, was invited to speak at the Public Hearing of the Budgetary Committee of the House of Councilors on March 22, 2012, on the Fukushima nuclear power plants accident. Before the Committee, Ambassador Murata strongly stated that if the crippled building of reactor unit 4—with 1,535 fuel rods in the spent fuel pool 100 feet (30 meters) above the ground—collapses, not only will it cause a shutdown of all six reactors but will also affect the common spent fuel pool containing 6,375 fuel rods, located some 50 meters from reactor 4.

In both cases the radioactive rods are not protected by a containment vessel; dangerously, they are open to the air. This would certainly cause a global catastrophe like we have never before experienced. He stressed that the responsibility of Japan to the rest of the world is immeasurable. Such a catastrophe would affect us all for centuries. Ambassador Murata informed us that the total numbers of the spent fuel rods at the Fukushima Daiichi site excluding the rods in the pressure vessel is 11,421 (396+615+566+1,535+994+940+6375).

I asked top spent-fuel pools expert Mr. Robert Alvarez, former Senior Policy Adviser to the Secretary and Deputy Assistant Secretary for National Security and the Environment at the U.S. Department of Energy, for an explanation of the potential impact of the 11,421 rods.

I received an astounding response from Mr. Alvarez [updated 4/5/12]:

In recent times, more information about the spent fuel situation at the Fukushima-Dai-Ichi site has become known. It is my understanding that of the 1,532 spent fuel assemblies in reactor No. 304 assemblies are fresh and unirradiated. This then leaves 1,231 irradiated spent fuel rods in pool No. 4, which contain roughly 37 million curies (~1.4E+18 Becquerel) of long-lived radioactivity. The No. 4 pool is about 100 feet above ground, is structurally damaged and is exposed to the open elements. If an earthquake or other event were to cause this pool to drain this could result in a catastrophic radiological fire involving nearly 10 times the amount of Cs-137 released by the Chernobyl accident.

The infrastructure to safely remove this material was destroyed as it was at the other three reactors. Spent reactor fuel cannot be simply lifted into the air by a crane as if it were routine cargo. In order to prevent severe radiation exposures, fires and possible explosions, it must be transferred at all times in water and heavily shielded structures into dry casks.. As this has never been done before, the removal of the spent fuel from the pools at the damaged Fukushima-Dai-Ichi reactors will require a major and time-consuming re-construction effort and will be charting in unknown waters. Despite the enormous destruction cased at the Da–Ichi site, dry casks holding a smaller amount of spent fuel appear to be unscathed.

Based on U.S. Energy Department data, assuming a total of 11,138 spent fuel assemblies are being stored at the Dai-Ichi site, nearly all, which is in pools. They contain roughly 336 million curies (~1.2 E+19 Bq) of long-lived radioactivity. About 134 million curies is Cesium-137 — roughly 85 times the amount of Cs-137 released at the Chernobyl accident as estimated by the U.S. National Council on Radiation Protection (NCRP). The total spent reactor fuel inventory at the Fukushima-Daichi site contains nearly half of the total amount of Cs-137 estimated by the NCRP to have been released by all atmospheric nuclear weapons testing, Chernobyl, and world-wide reprocessing plants (~270 million curies or ~9.9 E+18 Becquerel).

It is important for the public to understand that reactors that have been operating for decades, such as those at the Fukushima-Dai-Ichi site have generated some of the largest concentrations of radioactivity on the planet.

Many of our readers might find it difficult to appreciate the actual meaning of the figure, yet we can grasp what 85 times more Cesium-137 than the Chernobyl would mean. It would destroy the world environment and our civilization. This is not rocket science, nor does it connect to the pugilistic debate over nuclear power plants. This is an issue of human survival.

There was a Nuclear Security Summit Conference in Seoul on March 26 and 27, and Ambassador Murata and I made a concerted effort to find someone to inform the participants from 54 nations of the potential global catastrophe of reactor unit 4. We asked several participants to share the idea of an Independent Assessment team comprised of a broad group of international experts to deal with this urgent issue.

I would like to introduce Ambassador Murata’s letter to the UN Secretary General Ban Ki-moon to convey this urgent message and also his letter to Japan’s Prime Minister Yoshihiko Noda for Japanese readers. He emphasized in the statement that we should bring human wisdom to tackle this unprecedented challenge.

Ambassador Murata’s letter says:

It is no exaggeration to say that the fate of Japan and the whole world depends on NO.4 reactor. This is confirmed by most reliable experts like Dr. Arnie Gundersen or Dr. Fumiaki Koide.

Anti-nuclear physician Dr. Helen Caldicott says that if fuel pool 4 collapses, she will evacuate her family from Boston and move them to the Southern Hemisphere. This is an especially dramatic statement given that the West Coast is much more directly in the path of Fukushima radiation than the East Coast.

Will humanity rise to the occasion, and figure out how to stabilize fuel pool number 4 before catastrophe strikes?

Or will modern civilization win a Darwin award for failing to pay attention to the real threats?



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