* The highest level of this element in 2012 was 11 becquerels of plutonium-238 per square meter, measured at Namie—only 1.4 times greater than what fluttered down in average everyday fallout, courtesy of the nuclear testing club of nations. How fortunate that it wasn’t Pu-239! But the time for the latter isotope’s radiation to reduce to 1/1000 was a mere 877 years.