Sharon Begley warns of an underreported danger in Japan:
The spent fuel produced by reactors has been a challenge since the dawn of the nuclear industry, with most reactor operators opting to store it in pools of cooling water on site. At the 40-year-old Fukushima plant, which was built by General Electric, the fuel rods are stored at a pool about three stories up, next to the reactor (a schematic is here). Satellite photos raise concerns that the roof of the building housing the pool has been blown off, says Robert Alvarez, a senior scholar at the Institute for Policy Studies and a senior policy adviser to the secretary of energy and deputy assistant secretary for national security and the environment from 1993 to 1999. He and other experts are now warning that any release of radioactivity from the spent-fuel pool could make the releases from the reactors themselves pale in comparison.
Barry Brook provides a summary of the current status at Fukushima.