2011 was a scary year for nuclear reactor sites. The summer floods threatened to encroach on reactors in Nebraska and Iowa, an earthquake and a hurricane happened in quick secession to rattle and flood the East Coast, and the continuing events of the Fukushima-Daiichi reactor accident provided harrowing examples of the threats posed to spent fuel at reactor sites. The fate of spent fuel there kept the world on edge for days. It's worth noting that the amount of fuel in vulnerable storage pools in Japan was far less than what is crowded into pools at many U.S. reactors. As we all learned, a loss of coolant could produce a fuel melt and large radiation releases.