The head of the International Atomic Energy Agency says he will travel to Japan to gather firsthand information about the crisis at an earthquake-damaged nuclear power plant, after stating that the agency needs more timely information from the Japanese government.
Speaking at a news conference Wednesday in Vienna, IAEA Director-General Yukiya Amano said he hopes to arrive in Japan as early as Thursday and to stay for a day. He said he would meet with high-level officials and discuss what assistance the United Nations nuclear agency can provide.
The IAEA has been trying to assess the situation at the Fukushima Dai-Ichi plant from afar.
US Military sets 'no-go' zone
The Pentagon said Wednesday that U.S. forces in Japan are now not allowed within an 80-kilometer radius of the crippled Fukushima plant, on fears of radiation exposure.
Meanwhile, a small team of Japanese workers at the plant continue emergency efforts to pump water into the facility's reactors to keep the nuclear cores from melting down and releasing radiation into the atmosphere.
Plant operators began the emergency measures after Friday's 9.0-magnitude earthquake and a subsequent tsunami knocked out cooling systems at the reactors. The workers were temporarily evacuated from the facility Wednesday after radiation emissions rose to dangerously high levels.
Assessing damage, contingency plans
Officials also had to cancel plans to drop water by helicopter onto the damaged number 3 reactor after deciding radiation levels were too high to safely conduct the operation.
Television images showed white plumes rising from the building housing the number 3 reactor. Chief Cabinet Secretary Yukio Edano told reporters in Tokyo it was probably steam escaping from a rupture in the containment chamber housing the unit's nuclear core.
Officials announced a similar rupture in the chamber of the number 2 unit a day earlier.
Japanese police plan to dispatch water cannons to douse a storage pool holding spent fuel at the number 4 reactor, after another fire broke out there, releasing a plume of radiation, before it was put out.
Radiation levels monitored
Residents within 30 kilometers of the plant have been told to remain inside to limit the risk of radiation exposure.
The IAEA also said radiation has risen slightly in Tokyo, 240 kilometers to the south, but not to levels considered dangerous to human health. Still, concerned citizens in the capital have scrambled to buy up facemasks, food and other supplies at local markets out of fear the situation will worsen.
Some foreign governments have warned their nationals to leave or avoid travel to the capital.
At the time of the earthquake, only the reactors at units 1, 2 and 3, were in use, and were inside thick concrete containment chambers designed to hold in any radiation, even if the rods melt down. Explosions have destroyed the outer buildings of all three of the units, however, caused when technicians vented steam from the containment chambers to ease a dangerous buildup of pressure.
Officials said the chambers surrounding units 2 and 3 now have been cracked, allowing radiation to escape.
Cooling the fuel rods
The fuel rods at units 4, 5 and 6 had been removed for maintenance weeks before the earthquake struck and placed in cooling ponds outside the containment chambers
Even when they are not in use, nuclear fuel rods remain very hot for weeks or months. Unless they are kept cool with a steady supply of water, their outer casings can melt away releasing radiation into the air.
A small team of emergency workers have been pumping seawater onto the fuel rods at all six of the plant's reactors. Japan's Health Ministry earlier announced it was raising the legal limit to the amount of radiation exposure allowed for workers, allowing them to work longer at the site.
Tens of thousands of people have been evacuated from within a 20-kilometer radius of the plant, and residents within 30 kilometers have been advised to remain in their homes.
The drama has caused alarm across a country already traumatized by the largest earthquake ever recorded in Japan.
The governor of Fukushima prefecture, Yuhei Sato, said at a news conference that panic caused by inaccurate reporting of the nuclear crisis is preventing relief supplies from reaching the evacuees and victims of the earthquake. He urged nuclear power company officials to give out more accurate information and appealed to all Japanese to extend help to those who have been evacuated.
Edano said Japan is preparing to ask the United States for technical assistance and may reach out to other countries. The International Atomic Energy Agency also is preparing to dispatch a team of experts.
Some information for this report was provided by AP, AFP and Reuters.