



What happens to nuclear reactors like those at Fukushima after they melt down or reach the end of their useful lives?
By David Biello | April 29, 2011 | 3
On March 11, a magnitude 9.0 earthquake spawned a 14-meter-tall tsunami that swept over the Fukushima Daiichi nuclear power plant on the northeast coast of Honshu, Japan's main island....[More]
On March 11, a magnitude 9.0 earthquake spawned a 14-meter-tall tsunami that swept over the Fukushima Daiichi nuclear power plant on the northeast coast of Honshu, Japan's main island. As a result of the loss of electric power, all three of the operating reactors began to melt down, setting off hydrogen explosions at reactor Nos. 1 and 3 that destroyed the surrounding buildings (pictured) on March 15. [Less] [Link to this slide]
As the tsunami hit, the Fukushima Daiichi nuclear power plant was already shutting down as a result of safety precautions triggered by the earthquake.
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The 14-meter-high wall of water easily overtopped the nuclear power plant's seawall and flooded access roads as well as swept away fuel tanks for backup diesel generators....[More]
The 14-meter-high wall of water easily overtopped the nuclear power plant's seawall and flooded access roads as well as swept away fuel tanks for backup diesel generators. As a result, the reactors ran out of power to run the pumps that supplied cooling water to cover the hot nuclear fuel rods. Within hours, a meltdown began. [Less] [Link to this slide]
Not only did the fuel in the operating reactors begin to melt down, but so did spent fuel stored in nearby pools. Such a pool sparked a hydrogen explosion at the plant's reactor No....[More]
Not only did the fuel in the operating reactors begin to melt down, but so did spent fuel stored in nearby pools. Such a pool sparked a hydrogen explosion at the plant's reactor No. 4, which had not been operating when the earthquake struck, and destroyed the building as shown here. [Less] [Link to this slide]
As a result of the explosions at the three operating reactors, radiation levels spiked, forcing the evacuation of control rooms at the nuclear power plant, like the one for reactor No....[More]
As a result of the explosions at the three operating reactors, radiation levels spiked, forcing the evacuation of control rooms at the nuclear power plant, like the one for reactor No. 2 pictured here. Damage from the earthquake, tsunami, meltdown and explosions also caused gauges and other instruments to malfunction. [Less] [Link to this slide]
In order to protect workers from high levels of radiation, various forms of plastic shielding and special breathing apparatus are required (pictured)....[More]
In order to protect workers from high levels of radiation, various forms of plastic shielding and special breathing apparatus are required (pictured). Regardless, it will be nearly impossible for workers to get close to the melted down reactors, given that Tokyo Electric Power has measured radiation exposure levels as high as 300 millisieverts per hour in some places in the stricken nuclear power plant—or 50 millisieverts more than plant workers are allowed to endure over an entire year. [Less] [Link to this slide]
The first priority in getting the Fukushima meltdown under control is applying cooling water to the hot nuclear fuel. Here workers employ a tall pumping crane (more commonly used to pump concrete into the upper stories of tall buildings under construction) to spray water onto the hot fuel....[More]
The first priority in getting the Fukushima meltdown under control is applying cooling water to the hot nuclear fuel. Here workers employ a tall pumping crane (more commonly used to pump concrete into the upper stories of tall buildings under construction) to spray water onto the hot fuel. [Less] [Link to this slide]
The water that is not simply released into the atmosphere as steam or dumped in the ocean is stored in these big tanks, awaiting filtration and cleanup.
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Once the nuclear fuel is cool, workers will attempt to tear down the stricken nuclear power plant using remote-controlled heavy machinery like the power shovel and dump truck on tank treads pictured here....[More]
Once the nuclear fuel is cool, workers will attempt to tear down the stricken nuclear power plant using remote-controlled heavy machinery like the power shovel and dump truck on tank treads pictured here. [Less] [Link to this slide]
Because of the high radiation levels around the plant, even the cleanup of the detritus from the tsunami must be done remotely (pictured), and workers must wear full protective gear, including breathing apparatus....[More]
Because of the high radiation levels around the plant, even the cleanup of the detritus from the tsunami must be done remotely (pictured), and workers must wear full protective gear, including breathing apparatus. [Less] [Link to this slide]
To get a better idea of radiation levels and damage in places that humans cannot go, robots with radiation hardened electronics have been used, like the PackBot pictured here opening a door at Fukushima Daiichi....[More]
To get a better idea of radiation levels and damage in places that humans cannot go, robots with radiation hardened electronics have been used, like the PackBot pictured here opening a door at Fukushima Daiichi. Of course, radiation wreaks havoc on electronics, ranging from robots to cameras, too. [Less] [Link to this slide]
Because the fuel rod meltdowns were not entirely contained, radioactive particles, such as cesium 137, have escaped into the surrounding environment, including towns as far as 30 kilometers away....[More]
Because the fuel rod meltdowns were not entirely contained, radioactive particles, such as cesium 137, have escaped into the surrounding environment, including towns as far as 30 kilometers away. Here workers spray plastic on the ground in an attempt to encapsulate the particles and prevent them from spreading. [Less] [Link to this slide]
Ultimately, years later, spent fuel rods that have not melted down can be shifted into massive casks, like the one pictured here, for semipermanent storage....[More]
Ultimately, years later, spent fuel rods that have not melted down can be shifted into massive casks, like the one pictured here, for semipermanent storage. Japan has no long-term repository for such spent fuel, relying on on-site storage, although it has opened a facility to recycle such spent fuel at Rokkasho in the far north of Honshu. But that site has yet to commence operations due to various malfunctions. [Less] [Link to this slide]
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3 Comments
Add CommentHello, I am a science writer at Idaho National Lab and want to say that Mr. Biello did a really nice job on this article. It's well researched and written.
Reply | Report Abuse | Link to thisHowever, there's one small problem with one of the quotes from INL's Doug Akers. On page 3, it says: "Only 3 to 4 percent of the reactor inventory [of radioactive material] was released," Akers says.... It should say that only 3 to 4 percent of the reactor inventory of noble gases was released, whereas effectively all the other fission products (including plutonium and uranium) were retained in the containment or in the reactor vessel.
Thanks for the opportunity to clarify this information.
Nicole Stricker, Idaho National Lab
Some low dose radiation is not dangerous, it can even make you healthier?
Reply | Report Abuse | Link to thisQuick doses under 100 mSv and longer term doses under some thousand mSv/year are not dangerous.
Chernobyl experience tells that.
Small micrometer sized particles from coal, oil, wood, biomassa burning,.. are much more dangerous- millions of people die every year because of these...
See more
www.ncbi.nlm.nih.gov/pmc/articles/PMC2592992/
www.ncbi.nlm.nih.gov/sites/ppmc/articles/PMC2889503/
Who is going to pay for environmental damage that is being done by dirty technology? The question is not whether nuclear is safer than coal. Both need to be replaced by clean technology.
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