Japan's nuclear crisis intensified dramatically on Wednesday after authorities announced that a second reactor unit at the stricken Fukushima Daiichi plant in northeastern Japan might have ruptured and appeared to be releasing radioactive steam.
The break, at the No. 3 reactor unit, worsened the already perilous conditions at the plant, a day after officials said the containment vessel in the No. 2 reactor had also cracked.
Such were the radiation levels above the plant, moreover, that the Japanese military put off a highly unusual plan to dump water from helicopters, a tactic normally used to combat forest fires, to lower temperatures in a pool containing spent fuel rods that was overheating dangerously.
At the same time, the reactor's operator, Tokyo Electric Power Co., said it had been able to double the number of workers at the plant to 100 from 50. It was not immediately clear when the additional workers returned to the plant.
The vessel that possibly ruptured on Wednesday had been seen as the last fully intact line of defense against large-scale releases of radioactive material from the stricken reactor, but it was not clear how serious the possible breach might be. The implications of overheating in the fuel rod pool, which is also at the No. 3 reactor, seemed equally dire.
The developments were the latest in Japan's swirling tragedy since an earthquake and tsunami struck the country with unbridled ferocity last Friday. Emperor Akihito told the nation on Wednesday he was “deeply worried” about the nuclear crisis.
The company operating the reactors had withdrawn most of its workers from the plant on Tuesday, leaving only a skeleton crew of 50 struggling to lower temperatures.
When those workers were forced to suspend cooling operations, the spent fuel rod pool began heating up dangerously.
Among the authorities' main concerns are pools for spent fuel rods at several reactors at the plant, including Reactor No. 4, where the pool has lost some of the water needed to keep the fuel rods stable. — New York Times News Service
