Nukewatch Quarterly Summer 2016
By Richard Stone
Two weeks after the March 11, 2011 earthquake and tsunami devastated the Fukushima Daiichi Nuclear Power [complex], causing three nuclear reactors to melt down and release radioactive plumes, officials were bracing for even worse. They feared that [waste] fuel … would catch fire and send radioactive smoke across a much wider swath of eastern Japan, including Tokyo.
Thanks to a lucky break detailed in a report released May 27 by the US National Academies, Japan dodged that bullet. The near calamity “should serve as a wake-up call for the industry,” says Joseph Shepherd … who chaired the academy committee that produced the report. … A major [waste] fuel fire at a US nuclear [reactor] “could dwarf the horrific consequences of the Fukushima accident,” says Edwin Lyman, a physicist at the Union of Concerned Scientists, a nonprofit in Washington, D.C., who was not on the panel….[At Fukushima] Unit 4 … the entire reactor core—all 548 assemblies—was in the spent fuel pool, and was hotter than fuel in the other pools. When an explosion blew off Unit 4’s roof on March 15, plant operators … feared it had come from fuel in the pool that had been exposed to air.…The blast had destroyed instrumentation for monitoring the pool. … [and] the possibility that the fuel had been exposed was plausible and alarming enough for then-NRC (Nuclear Regulatory Commission) Chair Gregory Jaczko on March 16 to urge more extensive evacuations than the Japanese government had advised…
The pool’s water was boiling away because of the hot fuel. As the level fell perilously close to the top of the fuel assemblies, something “fortuitous” happened, [chairperson] Shepherd says. As part of routine maintenance, workers …allowed water from the reactor well to leak into the spent fuel pool, partially refilling it. … Only good fortune … averted that disaster, the academy panel notes.
At US nuclear plants, [waste] fuel is equally vulnerable. … The panel recommends that NRC take another look at the benefits of moving spent fuel to other storage …”
—Richard Stone oversees Science magazine’s international coverage. This is a heavily edited version of his May 27, 2016 article in Science Online.
—Take Action! Hundreds of environmental and public interest groups have called for Hardened On-Site Storage (HOSS) of highly radioactive irradiated waste fuel at reactor sites, as an interim measure to improve safety and security. The first step in HOSS is to empty the densely packed vulnerable cooling pools, which are at risk of catastrophic fires. The waste must then be placed in hardened on-site dry casks (current dry cask models are not good enough). Tell Congress that HOSS must be required at all power reactors. See BeyondNuclear.org for details.