Japanese officials have warned of increasing radiation levels around an earthquake-damaged nuclear power plant, and have urged people living within a 30-kilometer radius to stay indoors.
In a nationally televised statement Tuesday, Prime Minister Naoto Kan said radiation has spread from the Fukushima nuclear plant, where explosions have occurred at three reactors since Friday’s massive earthquake and resulting tsunami. Mr. Kan said the radiation level is “very high” and he said there still is a very high risk of more radiation escaping.
Low levels of radiation were also detected in Tokyo, about 240 kilometers to the south, but officials said it was not a threat to public health.
The latest explosion at the Fukushima plant occurred Tuesday morning, following similar blasts on Saturday and Monday. Officials also said a fire broke out and was extinguished at a fourth reactor, which had been shut down before Friday’s earthquake but had spent fuel stored inside.
Several people were injured in the earlier explosions and non-essential staff were evacuated from the plant on Tuesday, but no deaths have been reported.
The troubles began when the earthquake and tsunami knocked out power on Friday, crippling the cooling systems needed to keep nuclear fuel rods from melting down.
On Monday, the U.S. Geological Survey upgraded the magnitude of the quake to 9.0 from the previous estimate of 8.9. There have been numerous aftershocks since the initial quake.
Engineers have been pumping seawater into the Fukushima plant to cool the fuel rods after the regular cooling systems were damaged by Friday’s quake. But the heat evaporated the water faster than it could be pumped into one of the units, and officials say the fuel rods have been exposed to air at least twice so far. Some of the rod casings may have melted in the heat, raising fears of a catastrophic meltdown.
Plant officials say that some radiation has been detected outside the plant. U.S. warships and planes helping with relief efforts moved away from the coast temporarily because of low-level radiation.
Almost 200,000 people have been evacuated from areas around Fukushima. The government has advised those who remain at home to keep indoors.
Residents in quake- and tsunami-hit regions are suffering from food, water and heat shortages. Many homes are without electricity and running water. The official death toll has reached more than 2,400, but authorities say they have not been able to contact about 10,000 other people, and that new bodies are constantly being washed ashore.
Power rationing began Monday across Japan. That is expected to last into April as the demand for electricity is expected to exceed supply.
About 100,000 Japanese troops, backed by relief teams from more than a dozen countries, are searching for survivors in the rubble.
Two U.S. search-and-rescue teams with 144 staff and 12 dogs, are among the teams that began clawing through the ruins at first light Monday in search of survivors. A 15-member Chinese team also was at work. Japan’s Kyodo news agency said the Defense Ministry will activate reserves to assist in relief operations, the first time it has done so.