I think this article is very well-written overall. However, there are still a point that could use clarification.
> During a routine test on April 26, 1986, reactor Number 4 at the Chernobyl Nuclear Power Plant experienced a power surge that triggered an emergency shutdown. It did not work.
Calling the incident a routine test greatly mischaracterizes what they were doing. This wasn't some sort of daily safety checklist test nor a safety margin test, this was a full-blown experiment. Yes, like a science lab experiment, but with a fully fueled commercial RBMK reactor. This is important because the author falsely makes routine nuclear powerplant operation seem unsafe.
To properly characterize the experiment on fair grounds it is nice to mention that the experiment they wanted to test is started by carrying out a simulated emergency shutdown. This is huge. You don't call an emergency shutdown of a gigantic plutonium-making-machine "routine" (Note: RBMKs have a thermal power output on the high side). However, the bigger problem was that the authorities running this experiment treated it exactly the same way the author did.
If the authorities did care, they would have properly trained the night shift personnel with the experiment (or delayed the experiment altogether). The fact that the experiment continued with the night shift that was poorly trained for the experiment operations points to a "this is routine and should not be a big deal" vibe of whoever was in charge. I dislike how nowadays others (such as the the author) looking into the reactor accident keep espousing this giant red flag.
"The Unit 4 reactor was to be shutdown for routine maintenance on 25 April 1986. It was decided to take advantage of this shutdown to determine whether, in the event of a loss of station power, the slowing turbine could provide enough electrical power to operate the emergency equipment and the core cooling water circulating pumps, until the diesel emergency power supply became operative. The aim of this test was to determine whether cooling of the core could continue to be ensured in the event of a loss of power.
This type of test had been run during a previous shut-down period, but the results had been inconclusive, so it was decided to repeat it. Unfortunately, this test, which was considered essentially to concern the non-nuclear part of the power plant, was carried out without a proper exchange of information and co-ordination between the team in charge of the test and the personnel in charge of the operation and safety of the nuclear reactor. Therefore, inadequate safety precautions were included in the test programme and the operating personnel were not alerted to the nuclear safety implications of the electrical test and its potential danger."
Of course, in hindsight it is obvioust that it was poorly executed. But it's not surprising that they were more relaxed doing the procedure for the second time, and again, during "the routine maintenance shutdown."
I'd take issue with the idea that there was no/minimal coordination with the reactor operators.
In fact, the issue that made the turbine spindown test such a disaster for Chernobyl was the extended amount of time and number of power excursions that that reactor (not non-nuclear) operators had spent trying to setup for the initial conditions of the turbine test.
The test had been intended for the afternoon shift, and required reactor power and steam output to be set within a prescribed band before the test. The operators duly setup these initial conditions, but then the regional electrical control center unexpectedly asked Chernobyl-4 to remain online (instead of shutting down as planned) to service electrical demands.
The reactor operators then resumed power operations and tried to re-establish test conditions at the end of their shift when they received permission to shutdown. But this shift from power operations to low power back to power operations and back again to low power induced xenon transients, and an extremely unusual and dangerous control rod configuration, all in an effort to establish the nuclear parameters to run the non-nuclear test.
And then they turned over to the evening shift as if they were handing over a set of car keys for a company sedan, an evening shift that had not been expecting the test (though by this point the conditions were such that either shift would have caused the reactor accident IMHO, assuming no one made the brave call to abort the test completely).
I'm willing to grant that professional nuclear testing groups were not actually involved in the design and implementation of the test, but it's simply not true that this was the result of a bunch of steam plant engineers running a test that was felt to be non-nuclear in nature. The nuclear reactor operators were deeply involved in setup and spent almost the entirety of a shift setting up for this test, and had plenty of opportunity throughout to evaluate the possible reactor plant response to their actions.
In fact had the test simply been to take a reactor operating at power and to spontaneously trip the steam supply valve to the turbines the accident would never have happened, even without coordinating with the reactor operators first. In the actual event the closure of the steam valve was simply the non-nuclear nudge that finally tipped off a disaster laboriously arranged during a full shift by nuclear reactor operators, operators who should have known better just from first nuclear principles.
Also, the experiment's requirement lead into the operators disabling almost every single safety mechanism. The automated systems disallowed the actions they were trying to do, so they disconnected most important security measures.
Operating like that you can make even hydroelectric power station extremely deadly, and kill a lot of people.
I can recommend Atomic Accidents: A History of Nuclear Meltdowns and Disasters: From the Ozark Mountains to Fukushima by James Mahaffey - it has a chapter on Chernobyl and goes into a fair amount of details:
No, the actions leading up to the explosion were anything but normal and routine. The operators went far outside the safety envelope of the reactor by deliberately disabling the mechanisms designed to prevent mishaps.
Chernobyl was caused by irresponsible and reckless behavior. You can't paint this as everyday operation, it's not even close.
I could write "Conduct improv brain surgery on the guy sitting next to me" in my daily planner and it doesn't make it routine. Calling a knife a fork doesn't make it so, and calling something routine that isn't likewise doesn't make it so.
While the article does contain some interesting details, I fundamentally disapprove of it's anti-nuclear moralizing. It's the constant trickle of articles like this that maintain public paranoia about nuclear power. This matters, because nuclear power allows us to meet today's power demands with today's technology without releasing CO2 into the environment. Alternative power sources are still some ways from meeting humanities power needs on their own, but every megawatt of nuclear power produced keeps carbon in the ground and gives us extra time. Yes, many will point out that several alternative power generation sources could be scaled up to meet all of humanity's demands right now. However, it's not being done because it's economically and technically challenging and would take decades.
Meanwhile, fully operational nuclear power plants are being shut down. After the Fukushima incident, Germany and several other countries caved into irrational public fears and have begun to phase out nuclear power, replacing it with much more immediately dangerous power sources such as coal. (It should be noted that there are relatively few reactors in Germany that are likely to be hit by a magnitude 9.0 earthquake and tsunami.) That's carbon emission free power that's online right now, being destroyed out of irrational fear and replaced with what is possibly our dirtiest source of power. This is what is going on in the world, but the author has published yet another fear-mongering article anyways. It's downright despicable.
I don't like fear-mongering either. But nuclear only looks cheap because a lot of costs are externalised. Prudent calculation of costs of insurance against accidents and waste storage for centuries make it unprofitable. Improvements in reactor safety often leads to humans behaving more carelessly. It is a penny-wise, pound-foolish technology, especially in densely populated areas.
Many of the existing reactors were designed in the 50s and 60s, and are overly complex; they grew out of designs that were used for production of nuclear material for weapons, and safety features were bolted onto the side (this was an era when seatbelts weren't required on automobiles!). More recent designs are significantly and inherently safer and simply can't get into the same kind of trouble that the older designs can.
Yet we treat all reactors the same. Nuclear = bad for some reason.
I'd much rather be getting rid of coal plants (which are far worse for us than nuclear plants in terms of carbon emissions, pollution and actual emitted radiation) and have a national resolve to build safer, modern nuclear plants. But the fear-mongering and bad politics make this impossible.
Alternate sources of energy can be worse. For instance, when you look at the total cost of solar cells (lots of end-to-end industrial infrastructure involving toxic chemicals and energy-hungry manufacturing) and deaths from installers falling roofs, nuclear starts to look a lot better, even with plants we have today.
But anti-nuke makes headlines, and gets people fired up, and is better for the oil and coal industries.
>But anti-nuke makes headlines, and gets people fired up, and is better for the oil and coal industries.
Agreed. Much as routine, daily road deaths don't typically make the headlines, the guy down the road dying of lung cancer is hardly newsworthy. In my experience most people are totally unaware of the enormous number of deaths attributed to coal burning (estimated at ~1 million per year globally by the WHO in 2008 [0])
I don't know the quality of the research, but in the wake of the Fukishima accident, NASA researchers published the following report, which estimated the number of deaths avoided by the use of nuclear power as a substitute of fossil fuel based power generation:
"Using historical production data, we calculate that global nuclear power has prevented an average of 1.84 million air pollution-related deaths and 64 gigatonnes of CO2-equivalent (GtCO2-eq) greenhouse gas (GHG) emissions that would have resulted from fossil fuel burning.
On the basis of global projection data that take into account the effects of the Fukushima accident, we find that nuclear power could additionally prevent an average of 420,000-7.04 million deaths and 80-240 GtCO2-eq emissions due to fossil fuels by midcentury, depending on which fuel it replaces." [1] [2]
Consider that the cost of coal, solar, wind, hydro is under-estimated because we don't take into account the externalized environmental issues and excess deaths.
If we're going to try to account for externalized costs for nuclear, we need to do it for all the others too, and the results would not be pretty.
Huh? We have a pretty good understanding of the externalised costs for these. There is no mystery for storing waste and there is a very strong understanding of how easy it is to decommission. What externalities are you talking about?
Similarly, coal and other fossil fuels only look cheap because currently nobody is paying for the climate change they cause.
We have to choose between evils. I think nuclear power is better, because nuclear waste is relatively easy to contain until we figure out what to do with it (for example burn it up in breeder reactors), whereas the world's climate is a system we don't fully understand and meddling with it can cause irreparable damage.
The costs of coal are externalized, and, historically, higher than nuclear --- not in the abstract, but in deaths per year. But practically nobody is afraid of coal.
Aside from waste storage there's also the cost of dismantling old reactors. The Wikipedia article on nuclear decommissioning makes for some depressing reading:
The elephant's foot exists and writing an article about it isn't fear-mongering. Also writing an article about it does not require the author to write another one about the problems of coal. There are lots of articles about the problems of coal written all the time, there's even something being called "Obama's War on Coal", apparently, although the Wall Street Journal doubts it exists http://blogs.wsj.com/experts/2014/11/28/why-the-war-on-coal-.... Sounds like an easy war though. The enemy is incapable of movement and burns readily. Incendiaries should work rather well. Those articles probably get pro-coal people grumbling in the comments that it is downright despicable how everyone focuses on coal.
Germany's and other countries' reactors are decades old designs that are fundamentally unsound, often enough built on tectonic faults or (in the case of Japan) at the sea. They are not secured against terrorist attacks or even the crash of a passenger jet. In the case of Germany's reactors, the containment is built to sustain the impact of a Phantom fighter, nothing more.
Reactor operators have constantly proven to be unworthy of trust, be it in Chernobyl, Harrisburg or Fukushima. Both their handling of operations as well as their handling of crisis never was up to standards - and every disaster was an exception to the rule.
Ridiculing the German outphasing of nukes with the argument that it is not a tsunami-prone country is both childish and irrational - irrational because it turns a blind eye to the risks that endanger nuclear power plants here - and the far more severe consequences of an accident. In Germany, the nukes are located straight in the most densely populated areas.
I guess it is how you look at it. Much of this article has issues but one of the most glaring is this one:
"Born of human error, continually generating copious heat, the Elephant’s Foot is still melting into the base of the Chernobyl nuclear power plant. If it hits ground water, it could trigger another catastrophic explosion or leach radioactive material into the water nearby residents drink."
One of the things this 'foot' proved was that the supposition that a meltdown would have a core melt through the ground and down into the center of the earth, aka the "China Syndrome" was false. The reason was of course that once the core became molten it begins to mix with the materials around it, that causes it to become diluted until it drops below criticality and then it ceases to be a threat. All western reactors (and all of those in Japan) have a pool of borosilicate sand underneath the reactor as just such a final safeguard. Should the core melt through to that, it turns the sand to borosilicate glass which kills neutrons and stops the reaction. Leaving behind a solid, cooling glass chunk. Not contaminating any groundwater and generally not going any further afield. It remains to be seen if any of Fukishima's core material made it as far as the sand underneath those reactors.
The 'foot' at Chernobyl isn't going anywhere, and in a couple of decades will be safe enough to chop up and dispose of more permanently. Unlike radioactive dust in the plant which was getting carried out of the containment building. I expect that within my kids lifetime people to be living once again in the surrounding area.
I saw a documentary that showed squatter-types already were living in the surrounding area - whatever the exclusion zone area was. They interviewed them, but they were 'meh' about the risk. They had the place to themselves and were pretty happy.
That all sounds very nice, but the Fukushima reactor material is still above ground and totally at risk of explosion and entry into the atmosphere if it is not continually water cooled. The cooling water has contaminated the entire nearby water system and the ocean.
All Japanese reactors have their material above ground and are at risk of at least a steam explosion if they are improperly handled. The point is that Fukishima is just as "safe" today as it was for the 20+ years of operation, just instead of producing power all of the processes are around dismantling it. Which is proceeding.
I understand the emotional fear of nuclear power, it is a scary thing for a number of reasons, not the least of which is that you could be dying of radioactive poisoning right now and not know it, and all you need to do to survive is to move over 50 feet but you don't know you have to do that. So you end up dying. That is the giant knot of emotion that wraps up the fear in many cases. I've suggested to folks that have that fear, wear a dosimeter. They are very sensitive, not very expensive, and can completely clear your worry that you have some how stumbled into an unknown radiation hazard. It isn't a stupid or crazy thing to do, it just sets your mind at ease that you are not being dosed with ionizing radiation that you can't see.
Did they dump a lot of 137Cesium into the ocean? Yes they did. Was that more than was dumped by a single nuclear test in the ocean at Bikini Atoll? No it wasn't. There was a paper in Science, not long after the event about tracking the radionuclides [1].
ah so china has a cavalier attitude to safety in coal mines. this also happens to make up a large percentage of the deaths worldwide attributable to coal. china is now rolling out nuke plants. as we've seen previously with high speed rail and coal mines, there will be a cavalier attitude to safety.
my prediction is the outcome will be an increase in the number of deaths due to nuclear power.
(no, you don't avoid all deaths with hydro, wind or solar either; in fact hydro has historically been one of the deadliest power sources thanks to the Banqiao accident where a dam failure killed 171,000 - even excluding that, though, hydro is far from free of deaths)
EDIT: Since I was being a bit snarky: The point is last I heard the number of deaths from installation of rooftop solar is higher than the number of deaths from nuclear power plants for equivalent amount of energy. Nuclear gets the headlines because the nuclear incidents we hear about are big and scary and rare and get hyped up.
You don't get massive worldwide news coverage because some guy fell off a roof while mounting solar panels and died. But he's just as dead, and it adds up.
You can't ignore the small incidents if their rate is high enough.
Overall, you could have meltdowns on a regular basis and nuclear would still be one of our safest alternatives. Chances are it will also be one of the alternatives with the lowest environmental impact: Less radioactivity released than coal, by orders of magnitude; far less land area affected by development than hydro, wind and solar.
I had always heard it as thirty years. The ten year estimate seems to be a newer development! (My guess is that fusion is becoming less theoretical and shifting into an engineering problem; still hard, but a bit more deterministic.)
Are you including the effective body count due to increased greenhouse gas emissions (for coal) and cancer incidence/habitat destruction (nuclear)? Not to mention the economic damage of the incredibly expensive reactors (nuclear) and pollution (coal), which can probably be abstracted into a body count as well due to poorer health and living conditions from pollution/wasted societal resources.
But no matter what you include for nuclear, you won't get the numbers very high.
> Not to mention the economic damage of the incredibly expensive reactors (nuclear)
It's not at all clear that nuclear is any more expensive than the alternatives if you accounts for the externalized costs of e.g. the huge bodycount from the alternatives.
You are assuming I am comparing nuclear to coal, or coal to nuclear...
You must be reading some pretty rosy estimates on nuclear energy compared to renewables if you think the costs make nuclear look good. And by costs I include dollars (the wastage of such having an impact on all our wellbeing as well by diverting from better solutions).
Actually, for anyone living in an actual city, bikes and cars are generally roughly equivalent in terms of trip time. For example, I have an 8km commute on the outskirts of Paris - it takes about 45mins, regardless of whether I run, ride a bike, take public transport, or drive a car. (Ok, to be more precise, in includi the time to change into sports gear for the bike / running. Without this the bike takes about 30mins. Running does actually take 45 mins run time.)
I think the biggest difference in mindsets between the US and Europe (other than the isolationism/socialism divide and religion) arises from their different scales.
Europe is far more densely populated. The cities are generally much closer to each other. There often isn't the equivalent of American "suburbs", instead there are more (and smaller) cities. Most people living in cities get around by walking or use the public transit.
Well, for what it's worth, I'm actually Australian, and our cities are very similar to those in the US. What I said holds as much for Perth or Sydney as it does for Paris and London. The key is that traffic congestion reduces average car speed to something roughly equivalent to what you do on a bike, ie 15-20km/hr...
This is off topic but I always find statements like the above rather bizarre. Why must humans insist on living in places where the environment is hostile to human life?
I guess its because I grew up in a place where heating is very rarely necessary, without cooling of any kind and have spent most of the last three years traveling around countries where you could theoretically walk around naked all year if you so desired but I increasingly find it bizarre how attached people are to living in locations that are ill-suited to humans.
Most of Eurasia is like that with several hundred million people living in regions with harsh winters.
Where would you re-settle four hundred million people?
Would they want to be unwelcome guests anywhere else?
As a species we lack fur, so we are really vulnerable to cold.
>Where would you re-settle four hundred million people?
No one is talking about resettling anyone. My question was just about why people individually choose to remain in places that feature temperatures well outside of the range compatible with our species. Others have covered it pretty well. Some combination of habituation, laziness and disliking hot summers basically.
People have been living in those cold climates long, LONG, before modern heating systems. More than "laziness and disliking hot summers" I would say that humans will settle wherever are resources that can support them, period.
An individual might move but that doesn't affect the topic we're talking about.
Also, moving is not easy: you have to learn new languages, acquire skills you did not have use for previously, and get a work permit.
(And for the hilarious part, we often see people from warm countries moving to more temperate ones because those are economically and politically better off)
> This is off topic but I always find statements like the above rather bizarre. Why must humans insist on living in places where the environment is hostile to human life?
Because by an unlucky twist of nature (physics and chemistry combined) the richest soils are found in temperate regions, so the lands that historically were capable of sustaining a high population density are in the colder regions, the ones where you need heating at least in winter.
Even now, with advances chemistry and fertilizers we'd not be able to sustain the worlds population if we all moved closer to the equator and gave up on regions that require heating at least in winter.
I grew up a bit farther than 45 degrees north of the Equator. I've been living in the tropics, about 22 degrees north, for 3 years now. I love my life here, but I still prefer the weather back home. You can always put on more clothes and/or walk more quickly, but you can't wear negative clothes.
Well, first of all just "moving" is a hassle. Then people, for whatever reason, tend to be attached to what they call "home." And third, probably, because we like it.
Does it matter why? Humans have been living in harsh environments since long before the beginning of written history, and I doubt it'll stop any time soon.
So it's now almost 30 years after Chernobyl, so if I read this naively:
> When this photo was taken, 10 years after the disaster, the Elephant’s Foot was only emitting one-tenth of the radiation it once had.
the Elephant's foot will currently have 1/1000th of the original radioactivity it had right after the disaster, and 10 years from now it will be down to 1/10,000th. At that rate it would be indistinguishable from background radiation within a century or so (just guesstimating here, but that's a lot of powers of 10 -- I'm probably being pessimistic).
I'm guessing that this is wrong, though, and that the radioactivity from longer half-life radionuclides will eventually start to dominate and the "effective half-life" will be much longer.
Does anyone have any idea how long it will be until Chernobyl blends into the background radiation?
Total activity decrease in realistic "atomic waste" is not at all exponential.
Try a simple example:
Take a mixture of two isotopes. The one isotope has a half-life of 1 year and there's so much of it, that the activity is 10 decays/second. There's also a second isotope in the mix, with a half-life of 100 years, but there's 100 times as much of it, so that in total, you also get 10 decays/second.
After 10 years, the first isotope will be down to 2^-10, so only 1/1000th is left, it will be hardly measurable. But the second one will have decayed only 1/10th of a half-time, almost everything is still there: You are now down to half of the original activity.
It's more complicated than that. As you point out, you don't have just one isotope, you have a whole grab bag of stuff. Here's the wrench in the works that adds the complexity, when a radioactive isotope decays it doesn't just go away, it decays into another isotope, sometimes one that is also radioactive and with its own half life.
What yoU end up with is a system of differential equations, which are actually easy to solve if you know how, but that level of calculus is beyond what most folks have studied.
Anyway, a situation that tends to be common is that you have one sort of longer lived isotope which ends up producing another isotope which decays fairly fast along a multi-step chain. This ends up producing a fairly high level of radiation for a significant time in a pseudo steady state. But it depends on the details.
I did a bit more reading, and found this crazy and scary graph. It's under "Uranium-232 Series Activity" near the bottom of this paper[1]. It shows that gamma ray output from U-238 increases > 5x a year after U-238 is first refined, and stays higher than originally was for >100 years.
It's due to the decay products of U-238 (and their decay products) all producing radiation that adds up to more than the original's.
In fact the base nuclear fuels are almost extraordinarily safer than the products of their use, speaking from a nuclear perspective alone. Nuclear fuel that is stable enough to be useful as a reactor fuel has such a long half-life (usually on the order of billions of years) that it's only very weakly radioactive. But the fission products formed from the fission of the fuel are much much more radioactive.
>I'm guessing that this is wrong, though, and that the radioactivity from longer half-life radionuclides will eventually start to dominate and the "effective half-life" will be much longer.
Exactly. From a report on Chernobyl [0]: "Most of the decrease [in radiation] in the coming years will be at only the rate of the physical half-life of 137Cs." Cesium-137 has a half-life of 30 years [1], so if we use the number given in the article (10,000 roentgens/hour) the dose is apparently 434 million times background radiation, 23 microroentgens/hour [2]. It would take over a millennium to reduce Cesium-137 by a factor of 434 million[3]
That's the Elephant's Foot, though. Randall Munroe cites Chernobyl as having 6 millisieverts/hour on average[4]. That's 3000 times background radiation [2], or a 350-year wait before Chernobyl emits the same amount [5].
This is obviously a simplification, though. Plutonium isotopes were released too [0], which have a much longer half-life (thousands of years). It's possible those small amounts of plutonium will emit enough radiation to make Chernobyl have noticeably higher radiation levels than the background dose for much longer.
A final caveat: I'm not an expert or even a devoted amateur. Your question just sparked my curiosity. Although, this New York Times article [6] says scientists say it takes about 10-13 half lives for an area to recover, which is close to my 350 year figure.
"Military people call such places "FRONTLINE", liquidators who worked at the Chornobyl nuclear station called it "ROOF COATING". It was the most contaminated, and therefore the most dangerous, place in the zone. The remains of the roof coating of the 4th reactor. The operation on decontaminating the roof lasted more than five months. We will tell about only two days."
Seems silly to me to just leave it sitting there for decades if its internal heat is being generated by how the isotopes are in close proximity to each other. Or I might be misunderstanding why it's generating its own heat.
Could they contain and cool down the waste by slicing off chunks of the mass and containing each chunk in lead-lined boxes? Essentially re-processing the lump into crude 'control rod' sized chunks and storing them in little lead boxes to contain the radiation being thrown off.
Yes, you are misunderstanding. There is no more chain reaction; the "close proximity" is irrelevant. The heat is generated by the unstable isotopes decaying. And there is nothing in the universe which can stop them from doing that.
It's a misunderstanding I had as well before I read detailed discussions of the Fukushima incident: stopping the chain reaction does not make a nuclear reactor "safe". It just prevents new highly radioactive material from being generated. But the material you already have is still generating massive amounts of radiation and heat, and if you're not able to dissipate that heat (which you want to do without also dissipating any of the material!) then the heat will build up, cause it to melt, and that will usually restart the chain reaction!
> Particles emitted from radioactive atoms are a form of ionizing radiation—they have enough energy to scramble atoms and molecules they crash into. (This is different from non-ionizing radiation, like the kind emitted by your cell phone, which does not have enough energy to break bonds.)
I think this is a poor explanation. Radiation from your cell phone is electromagnetic radiation. This is far different from a radiated particle, an actual proton or electron flying out.
Essentially a particle vs a wave, which is more of a difference than "not enough energy". Is that correct?
Gamma radiation (i.e. ionizing radiation) is just a highly energetic photons. Alpha and Beta particles are not photons, and are not referred to as ionizing radiation.
Bit off topic: On the first picture right at the top you can see through the workers. I read that this was caused by radiation, but to me it looks more as if they (or he) was simply moving during a longer exposure?
Is nuclear energy above or below break-even, as a whole? Or has the cost of the mess created by nuclear industry accidents and other indirect costs swamped the profits?
A disturbing thought is that Fukishima is an even more dire situation. The Pacific ocean will never be the same.
Which of the 507 other plants will be the next go into meltdown? I wonder how many of these disasters the planet can handle before it becomes inhabitable to all life.
The increase in radiation in the pacific is lost in the noise when compared to naturally occurring background radiation. There are some areas directly around Fukushima where that is not the case, and it is a big mess, but I would happily eat fish from the vast majority of the pacific.
A far bigger threat to our ocean is the Great Pacific Garbage Patch.
Whiel I agree with your statements, it should be noted that sometimes scuba-diving in nuclear reactor's pools isn't as safe and fun as originally intended.
[A diver not briefed on avoiding unknown objects picked up a highly activated bolt laying on the pool floor and received a substantial amount of radioactive dose.]
This just verifies that water is a good shield against radiation. The slides explained that any proximity to, not to mention physical contact, with the object would be highly dangerous but having a mere 1.4 meters of water in between the human and the object the dosage would be negligible.
The Fukushima accident was a rare event, dumped a small amount of waste compared to ongoing industrial operations, and the most worrying part of the waste that it dumped decays on the timescale of decades, and not millenia.
I don't have stats about what gets directly into the oceans, but when we mine gold, copper, and other ores, we create entire ponds called "tailings ponds" full of arsenic, cyanide, mercury, and all sorts of other nasty substances. These ponds leak into the environment on a regular basis. Short of seeping into the environment, many of these substances NEVER GO AWAY. THIS IS A HUGE PROBLEM.
Nuclear waste comes in small quantities, in neat, easy to handle packages, and the most dangerous elements in it will decay relatively quickly. Over the entire lifetime of the nuclear industry, less than 80,000 tons of radioactive waste have been produced. Meanwhile, one mine alone produced 237,000 tons of arsenic trioxide over its lifetime. This substance is just sitting in the abandoned mine now.
The most worrying part of the nuclear waste story, to me, is that NIMBYism and fear has blocked attempts to produce permanent, safe facilities for permanent sequestration, so it's stored almost as poorly as our super toxic tailings. At least there's less of it, and efforts are made to clean it up when it gets into the environment.
like gold and copper, nuclear fuel is also mined. the nuclear industry produces large volumes of finely pulverised long lived low-level radioactive wastes in the form of uranium tailings. Unlike arsenic and cynaide, the hazard posed by uranium is not onyl checmical, but also radioactive. Whereas these chemical pollutants can be neutralised by the right chemical reaction, the radioactive hazard of uranium mining wastes cannot be neutralised, only contained.
And yet, the tailings for uranium are much less in volume than the tailings (and eventual processed waste products) from the fuels that would replace it, like coal and oil.
Uranium itself is only weakly radioactive anyways (the kind of uranium you mine has a half life measured in billions of years). You'd be at more danger from radiation from walking out of the mine into the UV-filled sunlight, or from smoking cigarettes (which contain radioactive Po-210) than from working under the earth in a uranium mine (though you would admittedly want to wear a face mask).
In fact Congressional staffers receive more exposure to radiation than U.S. naval nuclear plant operators, because the nice granite-based buildings they work in contain pitchblende impurities (containing uranium), and yet those Congressional staffers are allowed to work in those buildings.
Yes, thanks for pointing that out. Uranium tailings are one of the biggest environmental issues with nuclear power, and one of the ones I never hear anyone mention.
The radioactive waste produced by the plants is more of a political issue than a technical one, as is the switch to far safer, more maintainable, non-proliferating reactor designs.
The statement that nowadays reactor engines can be designed that are "far safer" always riles me up a little bit because, of course, a few decades ago the OLD designs were already sold to the general public with the promise that they were "perfectly" safe. And if you had the temerity to question this, you were of course a Luddite.
Even the old Western designs are/were safe within the parameters of their design. Many are running even today because it has proven politically impossible to replace them.
The one major exception is Fukushima Dai-Ichi (which used one of the oldest BWR designs), and even Fukushima Dai-Ichi has not killed anyone from radiation directly.
But just to contrast, the nearby set of operating reactors at Fukushima Dai-Ni (which also used an old BWR design with a minor containment upgrade) both managed to safely achieve cold shutdown even despite getting hit by the exact same tsunami that hit their sister site just a few kilometers up the coast.
Obviously you should always question the safety of a new technology instead of blindly trusting it. The modern reliance on computers and the magic of the Internet seems to come to mind for me as an example of where blind trust leads to problems. But questioning nuclear just because it's nuclear may well have made one a Luddite. The basics of nuclear engineering are not actually as difficult to understand as it's portrayed to be, but people object to the technology without even the slightest attempt to understand it, which may well make one a Luddite as well.
Enjoy your fish! I for one am taking heed of the warning signs from the thousands of dead animals washing up on the shores of the west coast - not to mention the alarming drop in the number of sea-urchins, starfish, shellfish, and other species who simply cannot be found.
"A far bigger threat to our ocean is the Great Pacific Garbage Patch."
...compared to the mind-boggling amount of commercial waste we dump into the environment in a completely unmonitored, uncontrolled, unlimited way the radioactive contamination of the Pacific is absolutely insignificant.
Maybe it will even help the ecological systems there a tiny little bit because (even if only few...) people might back down on seafood from the over-fished areas there.
Are you aware that our whole planet is warmed by the decay of thorium and other heavy elements below the crust? Geothermal energy is nuclear energy.
To respond to your question, Earth would get over it, and humanity would survive even 507 meltdowns. Fukushima was an exceptional case on a 40-year-old design, so we wouldn't have 507 Fukishimas (keep in mind how many people died from the giant tsunami that caused the Fukushima meltdown).
I'm no expert, but I suspect there's a big difference between the planet's naturally occurring radiation and the high volume of unstable particles spewing out from the Fukishima meltdown everyday.
What people never seem to understand is that the proximity of the source matters.
Compare a tiny amount of radiation coming from a long distance (say the core of the earth) and a tiny amount of radiation coming from speck of decaying radioactive material released by Fukushima that is floating around in the air of your office room. You measure the radiation in the room and sure enough the radiation is very weak. You conclude "See? Fukushima is no worse than natural radiation". Now what happens if you're so unfortunate to inhale that speck of material and it settles in your lungs? Then the picture changes completely because some cells of your lungs will now be very close to the source of radiation and these cells -- and always the same cells -- will be subjected to a long period of intense radiation.
> a tiny amount of radiation coming from speck of decaying radioactive material released by Fukushima that is floating around in the air of your office room.
By that logic, we should panic if we inhale the sweet scent of someone eating a banana, or walk by a soy farm with the obvious smell of fertilizer. What people actually never seem to understand is that you live in a world already filled with natural radionuclides, they are not simply buried deep in the Earth's mantle, they are everywhere around us.
What airborne radioactivity is floating in your office from Fukushima, by the way? And what type of radiation does that radioactive contamination emit; alphas and betas would effect local tissue, but neutrons and the much much more common gammas would have their interactions occur over a much much greater volume (possibly outside the body entirely).
Some of the potassium in your cells is radioactive and decaying right now at a rate of 4900 decays per second[0]. That's about as close as you can get to the source, and it's not a big deal.
You ignore the fact that the radioactive potassium will be distributed more or less evenly over your body.
Secondly, and more importantly, you bring up this number of 4900 decays per second as if it means anything by itself. Those 4900 decays per second are caused by the presence of 18 milligram of Potassium-40 in your body. One of the elements released by Fukushima is Iodine-131. If you ingest 1 microgram of Iodine-131, this speck will generate 4,6 BILLION decays per second. So yeah, you're right that 4900 decays per second is not a big deal. But then you conveniently forgot the fact that the material released by Fukushima is orders of magnitude more radioactive than Potassium 40.
The United States of America has detonated over 1,000 nuclear weapons singlehandedly. I imagine it would take much more than 507 commercial nuclear powerplants to render the entire Earth inhospitable.
That's like comparing a lit-match to a gas pipeline fire. Detonations dissipate quickly - the meltdowns are a constant flood of radioactive particles into our atmosphere. Only the fire doesn't end - because we don't have the technology to stop it, and perhaps will not ever.
So no, I don't agree - likely the number is much less than 507 and uncomfortably close to the number of plants already in disaster-mode.
A meltdown doesn't necessarily put any radioative particles into the air. If it did, that would be a very unusual event (such as Chernobyl). On the other hand, a bomb has a tendency to put an ultra-fine dust of uranium, various transuranics, and quite a few fission products into the atmosphere.
I suspect that you may be confusing a radioactive isotope (such as U235) with the particles associated with nuclear radiation (such as alpha and beta particles).
A meltdown will generally involve a lot of radioactive material. It will usually be localized and only very rarely pulverized into a dust. Chernobyl's steam explosion did this. The meltdown will probably also emit a lot of radiation, but that never "contaminates" the atmosphere, unless you consider electrons or helium "contamination".
Unfortunately, conflating radioactive isotopes with the radiation those isotopes emit when they decay is very common misunderstanding.
> That's like comparing a lit-match to a gas pipeline fire.
That's a terrible analogy. Radioactivity, a nuclear reaction, deals with totally different physics and phenomena than combustion, a chemical reaction.
A more proper analogy would be: Would you rather me shoot you with a cannonball once right now, or would you rather me split it up into a million little BB pellets and shoot one at you a day?
I'd choose the million little BB pellets a day because my body can recover from that in between. Likewise, your body constantly repairs DNA damaged by the sun or from other radiation sources.
Radiation, activity, and dosages are extremely difficult to keep straight. Especially when coming from the media. Not even units can help you (ex: Equivalent vs Effective Dose), and it is hard to keep straight (ICRP vs NRC).
> Only the fire doesn't end - because we don't have the technology to stop it, and perhaps will not ever.
I am not quite sure what you're referring to -- stick yourself in a heavily-lined lead chamber and I'm sure you will measure far less gamma radiation inside of it than outside.
> So no, I don't agree - likely the number is much less than 507 and uncomfortably close to the number of plants already in disaster-mode.
Then we can agree to disagree -- it seems you have already made your mind on how many plants are close to "disaster mode" (unsure what that really means in an engineering sense).
I have no physics education, I'm using common sense. They don't design bombs like they do core reactors. Bombs are intended to explode immediately, reactors are intended to help produce power for a very long time.
But hey, I'm listening - show me a chart that compares the total amount of ionizing radiation released into the atmosphere by bombs dropped on Nagasaki & Hiroshima versus the amount produced already by the Fukishima site.
Please don't use 'common sense' and talk about how they design bombs and core reactors when you have no physics education. But hey, I'll humour you with as crude comparison as I can string together in a few minutes.
This link [1] roughly compares Chernobyl to a Fat Man equivalent, which had a 21kT yield, or 0.021 MT. That's 0.003% of the total yield of all the atomic tests mankind has conducted (545MT total [2]).
So by a first cut of the numbers, we've set of 26,000 Fat Man equivalents. Even considering that Caesium ratio of 890:1 between Chernobyl to Fat Man, that's over 29 Chernobyls worth of the stuff flung out. Pick any of the other ratios and it looks worse for your argument.
Oh, and on the note of you freaking out about the amount of radiation that Fukishima is dumping into the Pacific and how it's screwing up all the ocean life, remember that about 10% of all of those explosions were detonated into the ocean half-way between the US and Japan.
>Please don't use 'common sense' and talk about how they design bombs and core reactors when you have no physics education.
If I can step back from mrschwabe's immediate questions, I'd like to point out how problematic your attitude is, NamTaf.
Nuclear power generation in the West is a political question. Which means its future is going to be decided by the average voter. The average voter is not going to have a "physics education". Maybe they took high-school physics[1], and maybe that class touched on radiation and nuclear power generation. But odds are, even in that case, the average voter doesn't really remember it.
I just checked my alma mater's undergraduate physics course catalog, and nuclear physics is an upper-division topic. It is unacceptable, in a democratic society, to suggest that voters have the right to an opinion on a topic of importance to society only if they've taken upper-division university classes on the topic in question.
The real failure isn't that mrschwabe doesn't have a physics education. The failure is that, 66 years after nuclear criticality was first used to power a light bulb, the physics/nuclear power advocate community hasn't figured out how to incorporate the basics of nuclear power generation into the average person's "common sense".
[1]Obligatory disclaimer about this being a U.S.-centric post. I'll let others comment on the quality of secondary-level physics instruction in other countries.
I'm not so convinced it's a purely political issue. I think there's equal parts of bureaucracy and technology in there too. Bureaucracy via the costs associated to run and maintain a plant, given the incredible red tape put in place, and technology in that to myk nowledge even the newest gen4 designs don't neatly and completely resolve the objections people have to them.
Are they good enough? Sure. They're good enoguh to convince anyone with an open mind. But they're not the problem. None of them are yet to the point to convince the person who is inherently against nuclear power. It's not yet at the stage where we can throw in some stuff, have it do its nuclear thing and produce energy, then do something very simple, easy, an un-fuck-upable such that there is no problematic waste at the end.
Maybe the technological aspect is political in disguise. I mean, it's easier to point at containers of nuclear waste than it is the airbourne pollutants that coal spews out. But I think you'll find that the easier solution to that problem comes from an improved technology that renders it null and void, rather than a change of political will. Particularly when semi-alternatives in the form of the various renewables exist and provide a much bigger attraction to the nuclear detractors even despite their flaws.
>I have no physics education, I'm using common sense.
That's a mistake. "Common sense", or the mental picture of "how things work" you've built up over a lifetime is utterly useless when it comes to nuclear devices. Things that common sense will tell you are super dangerous really aren't, and conversely things that common sense tells you should be safe are not at all safe.
The bombs dropped on Japan in World War II (Little Boy and Fat Man) were firecrackers compared to many of the thousands tested since then, which still haven't rendered our planet anywhere near uninhabitable.
Well, I think it's stupid of them, though they're of course "not" switching to coal. They're switching off their nuclear, and just haven't been able to replace the coal yet.
But it's not a given that their rollout of alternatives will be better/safer than nuclear either.
How fitting that the lone voice of dissent in this thread would eventually be charged with spreading religious propaganda. Guess we should have saw that one coming!
> During a routine test on April 26, 1986, reactor Number 4 at the Chernobyl Nuclear Power Plant experienced a power surge that triggered an emergency shutdown. It did not work.
Calling the incident a routine test greatly mischaracterizes what they were doing. This wasn't some sort of daily safety checklist test nor a safety margin test, this was a full-blown experiment. Yes, like a science lab experiment, but with a fully fueled commercial RBMK reactor. This is important because the author falsely makes routine nuclear powerplant operation seem unsafe.
To properly characterize the experiment on fair grounds it is nice to mention that the experiment they wanted to test is started by carrying out a simulated emergency shutdown. This is huge. You don't call an emergency shutdown of a gigantic plutonium-making-machine "routine" (Note: RBMKs have a thermal power output on the high side). However, the bigger problem was that the authorities running this experiment treated it exactly the same way the author did.
If the authorities did care, they would have properly trained the night shift personnel with the experiment (or delayed the experiment altogether). The fact that the experiment continued with the night shift that was poorly trained for the experiment operations points to a "this is routine and should not be a big deal" vibe of whoever was in charge. I dislike how nowadays others (such as the the author) looking into the reactor accident keep espousing this giant red flag.