![]() ![]() Nevertheless, government officials advised people living within a few kilometers of the plant to leave. In essence, the now-still water inside the reactors began to boil off, exposing the fuel rods and threatening a meltdown of the uranium fuel pellets inside.īy the evening of the first day, the Japanese government warned of cooling problems at the nuclear power plant and declared a “state of nuclear emergency,” though stressing that no radiation leaks had been detected. After eight hours, the batteries went dead - meaning the nuclear power plant had no electricity, and no way to cool itself. At the same time, the tsunami flooded critical electrical equipment. The back-up diesel generators that should have kicked in when power was lost did not survive the tsunami, which easily overtopped the seawall protecting the plant - leaving only batteries to run all the systems. The now-still water in the reactors began to boil off, threatening a meltdown of the uranium inside.īut because of the earthquake, no electricity could be delivered to the Fukushima-Daiichi nuclear power plant to run the cooling pumps. The key to cooling the rods is simple: flow water past them. That instantly stopped the fission of the enriched uranium fuel that allows a nuclear reactor to produce the steam that spins a turbine to make electricity.īut even with fission stopped, nuclear fuel rods must be kept cool, as byproducts of the nuclear reaction continue to break down and produce heat for years. When the earthquake struck at 2:46 p.m., the Fukushima-Daiichi nuclear power plant, along with at least three others, automatically shut down, sliding control rods - made of materials, like boron, that block neutrons - into the three reactor cores that had been up and running. ![]() A chronology of how the Fukushima crisis has unfolded demonstrates that even a country as advanced as Japan - and as practiced in dealing with natural disasters - was unprepared for an earthquake of this magnitude, the largest in Japan in 1,200 years. The disaster is clearly worse than the 1979 partial meltdown at Three Mile Island in Pennsylvania, yet not as grave as the 1986 explosion at the Chernobyl nuclear plant, which spread radioactive material over large portions of Europe. Amid the confusion, it was clear that some very basic mistakes - most noticeably placing backup diesel generators only slightly above sea level in a tsunami zone - had made the situation at Fukushima far worse.Įven now, 10 days after the crisis began, the situation at Fukushima is still not under control. In the ensuing days, the world has watched as Japanese engineers and plant workers have struggled to keep the fuel rods inside the crippled Fukushima plant from melting down, lurching from one crisis to the next as four of the complex’s reactors have experienced explosions and releases of radioactive material. Among the victims were at least 7,000 dead and 10,000 missing - as well as one nuclear power plant: Fukushima-Daiichi and its six reactors. Thirty minutes later, a wall of water roughly 250 miles long slammed into the northeast coast of the island nation, smashing everything in its path. On March 11, the ground beneath Japan swayed for as much as 5 minutes, a 9.0-magnitude earthquake that ultimately moved Japan some 2.4 meters (7.9 feet) closer to the United States.
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