Radioactive Steam Could Be Pumped Into Air for Months

Japan's attempts to avert a full-scale meltdown in its damaged nuclear reactors by flooding them with seawater has an ugly byproduct: radioactive steam, which may continue to be pumped into the air for weeks or even months, reports the New York Times. Operators periodically flood the cores with seawater, which cools the fuel by boiling—but steam from that heated water must be periodically released. Said one American official, “under the best scenarios, this isn’t going to end anytime soon.”

The trouble is that, even when shut off, nuclear reactors produce about 6% as much heat as they do when operating, and that needs to be cooled. Normal cooling operations could be restored if the electricity was reestablished, but that would require technicians to work in highly radioactive environments—and in order to hook up backup diesel generators, water would need to be pumped out of the flooded plant's lower levels. Despite the spread of radioactive steam across the Pacific Ocean, White House officials said that, "Hawaii, Alaska, the US Territories and the US West Coast are not expected to experience any harmful levels of radioactivity.” (More Japan earthquake stories.)