New Dangers Emerge at Fukushima

A confidential Nuclear Regulatory Commission document obtained by the New York Times details serious threats still facing workers at the severely damaged Fukushima nuclear plant, as well as previously undisclosed details about what has happened at the plant so far. Ordinarily, fuel in a nuclear plant cools to the point that it is easy to manage within several days after the reactor is shut down. But difficulty circulating water and damage to the fuel rods suggest keeping them cool could be a challenge for months.