Japan's Nuclear Crisis Deepens With Fire, Radiation Leaks
VOA - March 16, 2011
The crisis at Japan's earthquake-stricken nuclear plant is deepening, with radiation emissions rising Wednesday to levels that forced authorities to temporarily evacuate the last technicians from the facility.
National television showed pictures of helicopters being prepared to drop water onto the Fukushima power plant's damaged number 3 reactor, in a desperate attempt to lower temperatures and prevent the nuclear fuel rods inside from melting down.
But NHK Television said the military aborted the plan after another helicopter flew over the plant to monitor radiation readings. Chief cabinet secretary Yukio Edano said new preparations were under way late Wednesday to begin injecting water into the crippled reactor from the ground.
New fire erupts
Japanese awoke Wednesday to televised photos of a new fire at Fukushima's number 4 reactor, where a two-hour blaze on Tuesday released a plume of radiation that was detected as far away as Tokyo, 240 kilometers to the south. The new fire died down after a half-hour, and was soon replaced by clouds of white smoke pouring out of the number 3 unit.
At a press conference in Tokyo, Edano said the smoke 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.
Danger forces evacuation
Edano said the skeleton crew of about 50 workers still struggling to pump seawater onto the fuel rods at all six of the plant's reactors had been removed from the plant for their safety, but that radiation levels appeared to be dropping by midday. He said later that monitoring showed radiation levels within 30 kilometers of the plant were not so high as to pose a threat to human health.
Even when they are not in use, the 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.
At units 1, 2 and 3, the rods are inside thick concrete containment chambers designed to hold in any radiation, even if the rods melt down. But officials say the chambers surrounding units 2 and 3 have now been cracked, allowing radiation to escape.
Explosions have destroyed the outer buildings at all three of the units, caused when technicians vented steam from the containment chambers to ease a dangerous buildup of pressure. Seventy percent of the fuel rods at the number 1 reactor and 33 percent at the number 2 reactor are believed to have already been damaged or melted.
At units 4, 5 and 6, the rods were removed for maintenance before last week's earthquake and placed in cooling ponds outside the containment chambers. With the plant's pumping systems damaged by the earthquake and tsunami, those rods are also in danger of becoming exposed.
Worry spreads across Japan
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.
In Tokyo, residents have been buying up facemasks and protective gear while some foreign governments have warned their nationals to leave the capital.
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 is also preparing to dispatch a team of experts.
Japan's Nuclear Crisis Deepens With Fire, Radiation Leaks
Article from VOA
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