Know Nukes: The Japanese Earthquake & Anti-Nuclear Hysteria
Posted by mattusmaximus on March 13, 2011
Okay, this has been one helluva weekend for science (specifically, physics) and skepticism because of the earthquake in Japan, subsequent tsunami, and the ongoing situation with the nuclear power plants in the region. In this post, I am going to focus on the nuclear power plant question, because that is where the most amount of misinformation is being spread. And, sadly, because much of this misinformation is being spread by a horribly irresponsible media, I will not be referring to any media articles in this post.
First of all, let me say that I’m pretty mad at the manner in which this whole situation is being framed: while there are likely many tens of thousands of dead & dying victims in the wreckage of the earthquake & tsunami, much of the media focus is on the supposed “danger” posed by the nuclear power plants. Folks, this “danger” – while not completely fictitious – is being way, way, WAY over-hyped. In fact, it is being so overly-hyped that many people turning to most of the media are getting the impression that this is about to occur in Japan…
[**Update: Speaking of misinformation, there is a bogus "Nuclear Fallout Image" going around the Internet. More on that load of crap here.]
Let me continue by listing some reputable, scientifically accurate sources of information & updates on the situation with the Japanese nuclear plants and radiation in general. I strongly suggest that you turn off the TV and go to these sources for your information on the question of all things nuclear power & radiation oriented:
The World Nuclear News website (an outlet put together by nuclear engineering professionals and science journalists to get accurate information out to the public)
Nuclear energy 101: Inside the “black box” of power plants (one of the few mainstream media outlets that gets it right – kudos to you, Boing Boing! :) )
A Conversation with My Dad, a Nuclear Engineer, about the Fukushima Daiichi Nuclear Power Plant Disaster in Japan (from Skepchick Evelyn Mervine, who did an excellent job of cutting right to the chase regarding the scientific & technical issues involved)
Calculate Your Radiation Dose (from the United States’ EPA, which takes into account the natural & artificial sources of radiation around you all the time)
Now, having listed some reputable sources on the topic, let me take some time to address some of the more misinformed & outlandish claims being tossed all over the Internet and media landscape regarding what’s happening…
1) This could be another Chernobyl disaster!
No, that’s just plain wrong. First of all, it is important to note that the Chernobyl and Fukushima power plants are of a fundamentally different design; in fact, because of this design difference, I’m willing to go so far as to say that there is no way that the Fukushima plant could explode and disperse radioactive material in a large plume such as what happened with the Chernobyl incident. The primary difference lies in the fact that the Chernobyl core was graphite cooled, and graphite is a material which could burn & subsequently explode when heated enough by the reactor core (which is what happened, in part, at Chernobyl); whereas the Fukushima plant is a boiling water reactor, wherein the water cannot explode in a manner similar to what happened at Chernobyl.
In addition, it should be noted that the Chernobyl disaster rated a level 7 event (the highest rating) on the International Nuclear Event Scale, and it is the only such rating in history. By comparison, the Fukushima incident is ranking a comparatively modest 3 or 4 on the INES.
[**Update (3-16-11): I have seen some references around the Internet, and on the comments to this entry, that the INES rating for Fukushima has been upgraded to a 6 (or even to a 7). A 6 or 7 on the INES? That seems really high in light of the most recent events, the only source I can find for that is the Wikipedia page on the Fukushima plant, which references this German article.
And when I went to that article, the only thing it said in reference to the INES is this...
ATOMIC ACCIDENT (INES SCALE): An international scale, in order to evaluate the weight of nuclear accidents. It is enough from zero (event without or with small meaning in terms of safety) to seven (catastrophic accident). Starting from stage two one speaks of incident, starting from stage four of accident. The explosion of the nuclear reactor in Tschernobyl before scarcely 25 years was so far the only event of the stage seven. The partial core melt-through in the reactor Three Mile Island in the USA 1979 was arranged on stage five. With the misfortune in Japan stage six is to be expected at least after today's conditions, if there is and in its entirety disaster control measures is introduced a substantial release of radioactive material. Of Japan atomic energy authority in the nuclear power plant Fukushima classifies the incident so far however less badly than the incidents in the US nuclear power station Three Mile Island 1979 and in Tschernobyl 1986. The classification of an event takes over the operator of the power station, it however by the national atomic supervision and the international atomic energy authority in Vienna is examined and possibly corrected. (emphasis mine)
And that page doesn't reference anyone for where they got those estimates. So this is yet another example of sloppy reporting, because it basically says "if the absolute worst case scenario happens, it will be a 6 on the INES, but right how it ranks as a 4 according to the nuclear experts on site."]
2) The news keeps on talking about the danger of a meltdown!
True, but at the same time the news media are not telling people what exactly is and isn’t a meltdown. Unlike what some people fear, a meltdown is not – I repeat, NOT - something that would lead to a nuclear explosion! What a meltdown basically means is that the reactor core gets so hot that it… melts. While this makes a real mess of things – and is really expensive and time-consuming to clean up – it doesn’t necessarily mean that there is going to be a huge release of radioactive material into the environment. As long as the primary containment vessel at Fukushima holds, and all evidence indicates that this is indeed the case, even with a meltdown the core material will be kept separate from the outside environment.
So, in this particular case, a core meltdown would most likely lead to more of an economic disaster than an environmental one, due to the massive expense of cleaning it up.
3) Why didn’t they prepare for an earthquake?
They did. In fact, all Japanese nuclear power plants are specifically designed to withstand earthquakes, because – surprise – Japan rests in a highly earthquake prone region. In fact, taking into account the raw power of the earthquake (which apparently shifted the coastline of Japan by 8 feet and the Earth’s axis by 4 inches), I am rather surprised that the nuclear plants are holding up as well as they did.
Some people think the current trouble at Fukushima is a direct result of the earthquake, but it isn’t. First of all, as soon as the earthquake hit, the nuclear reactors went into automatic shut down mode. Now, please understand that shutting down a nuclear core is not as simple as turning off a light switch; even after the shut down procedure is initiated, it takes many days for the core of the reactor to cool because of the presence of so much residual heat (see the Boing Boing article above for an excellent analysis of this point). This is why the cooling system is so important, and in the case of Fukushima this is where the real problem came along once the tsunami hit. From what I understand, the water cooled system there was run by a set of diesel engines which failed after the tsunami flooded them. Once that happened, there was no way to effectively cool the core. Of course, there are now efforts underway to cool the core using seawater, and as long as the core temperature can be decreased – by whatever method – then in a few days the reactor core will be completely shut off.
Now, some people have made an argument that the danger of the diesel engines being flooded by a tsunami is an obvious design flaw, and I might agree. Regardless of whether or not there are design flaws, you can be rest assured that nuclear scientists & engineers will definitely learn from this incident and design better power plants.
4) The radiation inside the Fukushima plant control room is 1000 times greater than normal!
While I do not dispute this claim, I take issue with the fact that the media are not providing any context for the claim. What is a dangerous level of radiation? Why aren’t the media mentioning to people the question of radiation exposure, which incorporates both radiation intensity levels as well as exposure time? Why aren’t the media taking any time to mention to people that there are natural & artificial sources of radiation around all of us all the time? If you want to get a better idea of what this claim does and doesn’t mean, then I suggest you visit the link I referenced above about calculating your own personal radiation dosage (some of the sources will surprise you) in addition to reading up a bit on related health effects.
Once you take some time to actually learn about nuclear radiation, its sources, how much you’re exposed to on a regular basis, and so on, much of the fear regarding the issue goes away. Knowledge is power, folks.
5) Part of the nuclear plant blew up! How much radiation was released?
From what I understand now, the portion of the Fukushima plant that exploded did so because some hydrogen generated by reactions within the core was vented into the surrounding area and subsequently mixed with oxygen in the air, making it highly explosive. And yes, it did explode, causing much of the building around the primary containment vessel & reactor core to be destroyed. While this is problematic, because much of the pumping & cooling mechanisms are now gone, it isn’t as much of a disaster as some are claiming since the primary containment vessel is still intact.
**ETA: Here is an excellent diagram which outlines the situation…
In addition, if you’d like to know more basic information on how boiling water reactors work, I suggest taking a look at this material. [end edit]
As for the issue of radiation released, there was some radiation released in this event, but from the measurements I’ve read about it wasn’t that dangerous. The radioactive materials in this release have effectively been 1) dispersed by the wind, and 2) seem to have been composed mostly of short half-life materials which quickly decay away into a harmless state. Thus, any radiation hazard posed by this explosion would be both confined to a small area and relatively short-lived.
[**Update (3-16-11): It seems that within the last 24 hours there was a temporary increase in radiation coming from the Fukushima site, perhaps due to a fire at unit 4 - it is documented here. It should be noted that while those radiation readings did spike to about 400 milliseiverts/hour, they settled back down to about 0.6 milliseiverts/hour. The last time I checked (via World Nuclear News) it was still around 0.6 milliseiverts/hour = 60 mrem/hour, which is equivalent to about 2-3 chest x-rays per hour, which is a pretty hefty dose of radiation.
However, those are the readings on site at the Fukushima nuclear plant, not 30+ km away where civilians are located. And you must remember that the people on site are likely wearing protective gear, and they probably are not remaining on site for an extended period of time (I would guess they are rotating teams out to be safe & to keep dealing with the situation). It's serious, which is why they're dealing with it, but the sky is not falling.
Here's an analogy: think of firefighters battling a nasty blaze. The firefighters in the hottest part of the fire have to wear protective clothing, and they don't stay there for too long because it is too hot. Thus, they rotate out teams on a regular basis for both safety and to keep battling the blaze. Now, while it probably really sucks to be the firefighter doing this job, the rest of us can pretty much safely watch what is going on via TV without fear of suddenly bursting into flames :) ]
[**Update (3-17-11): If you want to get more regular, reliable updates, I suggest using the World Nuclear News website - here’s more from that site in a recent update…
… peaking at 400 millisieverts per hour (40,000 mrem/hour) on the inland side of unit 3, and 100 millisieverts per hour (10,000 mrem/hour) on the inland side of unit 4. At the highest exposure rate, a nuclear worker or soldier could remain in the area for less than 40 minutes before leaving the site, unable to return. …
… Despite high levels of radiation close to the units, levels detected at the edge of the power plant site have been steadily decreasing.
17 March, 4.00pm -- 0.64 millisieverts per hour (64 mrem/hour)
17 March, 9.00am -- 1.47 millisieverts per hour (147 mrem/hour)
16 March, 7.00pm -- 1.93 millisieverts per hour (193 mrem/hour)
16 March, 12.30pm -- 3.39 millisieverts per hour (339 mrem/hour)
It should also be noted that if the radiation levels are that low at the edge of the power plant site, then they are most likely well within acceptable levels by the time you get to the edge of the evacuation zone, 30+ km away. And there’s certainly no danger to people far beyond that point, including here in the United States.
In addition, a good reference on the levels of radiation exposure (and related health effects) can be found here - http://www.epa.gov/radiation/understand/health_effects.html#anyamount – note that those values are in rems, whereas most of the exposure I've been referencing in these reports is in milli-rems (mrems). Bottom line: the people who are going to be affected the most are the workers right there on site, and I wouldn’t be surprised if some of them are getting a potentially lethal dose; as for everyone else, I think the danger is practically non-existent.]
6) If there’s no danger, why are they evacuating so many people?
In one word: precaution. It isn’t that there is no danger involved with a scenario such as that at Fukushima, but the level of danger involved; it is a sensible precaution to simply move people away from the nuclear plants. This doesn’t then automatically translate into the “worst case scenario”, whatever that is. I also wouldn’t be surprised to know that another reason people are being evacuated from the area has to do with the danger of earthquake aftershocks and subsequent tsunami.
7) This disaster proves that nuclear power is dangerous!!!
Wrong. What this disaster proves is that nuclear power plants are built to be very rigorous & tough. When most other buildings in the region have been leveled by the earthquake and tsunami, these plants are holding up remarkably well. [**ETA: I really like how this article - Fukushima is a triumph for nuke power: Build more reactors now! - puts it...
Japan's nuclear powerplants have performed magnificently in the face of a disaster hugely greater than they were designed to withstand, remaining entirely safe throughout and sustaining only minor damage. The unfolding Fukushima story has enormously strengthened the case for advanced nations – including Japan – to build more nuclear powerplants, in the knowledge that no imaginable disaster can result in serious problems.
Let's recap on what's happened so far. The earthquake which hit on Friday was terrifically powerful, shaking the entire planet on its axis and jolting the whole of Japan several feet sideways. At 8.9 on the Richter scale, it was some five times stronger than the older Fukushima plants had been designed to cope with. ...
[end edit] In addition, as has been outlined above, once you get past all of the media hype & scaremongering out there, the situation is not nearly as serious as many people think. It is serious, but not that serious, folks.
Last, but not least, if you really want to put paid to the “nuclear power is dangerous” argument, let’s take a look at the number of fatalities associated with nuclear power over the decades as compared to other power industries…
Deaths per TWh for all energy sources
Coal – world average 161 (26% of world energy, 50% of electricity) Coal – China 278 Coal – USA 15 Oil 36 (36% of world energy) Natural Gas 4 (21% of world energy) Biofuel/Biomass 12 Peat 12 Solar (rooftop) 0.44 (less than 0.1% of world energy) Wind 0.15 (less than 1% of world energy) Hydro 0.10 (europe death rate, 2.2% of world energy) Hydro - world including Banqiao) 1.4 (about 2500 TWh/yr and 171,000 Banqiao dead) Nuclear 0.04 (5.9% of world energy)
In closing, let me reference a little humor… some people like to say “No nukes!” Personally, I like to say “Know nukes!” because once you start to understand the science and engineering involved, the topic becomes demystified and you can examine scenarios like Fukushima in a more calm & rational manner.
As for much of the news media & other scare mongers who are overly-hyping this thing, you get an extra special facepalm award…