March19, 2011– The “nuclear emergency” at the TEPCO (Tokyo Electric Power Company) Daiichi Fukushima continues to alarm the world, which is watching and hoping anxiously that a repeat Chernobyl does not happen.The spraying of water from buckets from helicopters may not help much as it is doubtful how much water would actually reach the reactor core to cool it and for how long can they keep on this “helicopter cooling” technique, especially with the radiation levels increasing.
Though the reactor core itself may not trigger a radioactive release as bad as Chernobyl, what about the spent fuel? Apparently there is enough spent fuel in the same facility that can be more dangerous than the reactor core itself.
Some more information about this hitherto unlooked at issue is given below in the Comments section on The Naked Capitalism blog.
The commenter quotes a research paper “Reducing the Hazards from Stored Spent Power-Reactor Fuel in the United States” which was submitted 2000; accepted for publication 2003, written by Robert Alvarez, Jan Beyea, Klaus Janberg, Jungmin Kang, Ed Lyman, Allison Macfarlane, Gordon Thompson, Frank N. von Hippel.
The authors state that “Because of the unavailability of off-site storage for spent power-reactor fuel, the NRC has allowed high-density storage of spent fuel in pools …virtually all U.S. spent-fuel pools have been re-racked to hold spent-fuel assemblies at densities that approach those in reactor cores. In order to prevent the spent fuel from going critical, the fuel assemblies are partitioned off from each other in metal boxes whose walls contain neutron-absorbing boron. It has been known for more than two decades that, in case of a loss of water in the pool, convective air cooling would be relatively ineffective in such a “dense-packed” pool. Spent fuel recently discharged from a reactor could heat up relatively rapidly to temperatures at which the zircaloy fuel cladding could catch fire and the fuel’s volatile fission products including 30-year half-life 137Cs, would be released. The fire could well spread to older spent fuel. The long-term land-contamination consequences of such an event could be significantly worse than those from Chernobyl”
Reader of this blog must be aware that the water in the spent fuel pools is quickly evaporating and the electric power outage implies that it would be difficult to cool these spent fuel boxes now. This is really alarming and should concern nuclear experts around the world.
Meanwhile, there were news reports online that said that a “Radioactive Plume” was rapidly spreading out from Fukushima and would soon reach America’s West Coast in a matter of hours. The level of radioactivity in the plume would however be much less and certainly below the “safe exposure” limits.