Japan worked to avert a meltdown at a stricken nuclear plant March 14 after a hydrogen explosion at one reactor and exposure of fuel rods at another. The fear at the Fukushima nuclear complex, 240 km (150 miles) north of Tokyo, was of a major radiation leak, Reuters reported. The complex has already seen explosions at two of its reactors on March 12 and 14, which sent a plume of smoke above the plant.
Yukiya Amano, head of the International Atomic Energy Agency, was reported by the news agency as saying the reactor vessels of nuclear power plants affected by the disaster remained intact, and so far, the amount of radiation released was limited. "The Japanese authorities are working as hard as they can, under extremely difficult circumstances, to stabilize the nuclear power plants and ensure safety," Amano was quoted as saying in a statement.
The plant operator, Tokyo Electric Power Co. (TEPCO), said fuel rods at the No. 2 reactor were fully exposed. The rods, normally surrounded by water, were partially exposed earlier after the engine-powered pump pouring in this water ran out of fuel. TEPCO said it was preparing to pump more cooling water on the rods.
There were earlier partial meltdowns of the fuel rods at both the No. 1 and the No. 3 reactors, where the explosions had occurred, and a TEPCO official described the situation in the No. 2 reactor was even worse than in the other units.
Officials said the thick walls around the radioactive cores of the damaged reactors appeared to be intact after the earlier hydrogen blast. But the government warned those still in the 20 km (13 mile) evacuation zone to stay indoors. TEPCO said 11 people had been injured in the blast.
"Everything I've seen says that the containment structure is operating as it's designed to operate. It's keeping the radiation in and it's holding everything in, which is the good news," Murray Jennex, a nuclear expert at San Diego State University was quoted by Reuters as saying. "This is nothing like a Chernobyl ... At Chernobyl (in Ukraine in 1986) you had no containment structure -- when it blew, it blew everything straight out into the atmosphere."
Nuclear fuel accounts for 30 percent of Japan's electricity. Of Japan's 54 reactors, 11 have been shut down by the quake.
Almost 2 million households were without power in the north, the government said. There were about 1.4 million without running water. Tens of thousands of people are missing.
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