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Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

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Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#71

Post by InclinedPlane »

cnvogel wrote: post #35
spatten wrote: post #25

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…

You are right, in that your guess is wrong ;-). 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…

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.

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#72

Post by acqq »

cjslep wrote: post #4

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 checkli…

It wasn't actually any science experiment, merely an engineering step to improve the emergency process, and not even performed for the first time:

https://www.oecd-nea.org/rp/chernobyl/c01.html

"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."

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#73

Post by beloch »

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.

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#74

Post by iSnow »

icelancer wrote: post #31
mrschwabe wrote: post #19

Earlier quoted context omitted.

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.

Yeah. The planet's naturally occurring radiation is a hell of a lot stronger and more dangerous.

Yeah and a hell of a lot better shielded. Come on, no need to pull the discussion to a moron's level.

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#75

Post by plikan13 »

ori_b wrote: post #38
justatdotin wrote: post #28

Earlier quoted context omitted.

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 waste…

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.

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#76

Post by happyscrappy »

vidarh wrote: post #44
mrschwabe wrote: post #2

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 radioactivity released by coal plants still dwarf the sum output of all recorded nuclear incidents many times over.

This makes Germany's switching from nuclear to coal quite ironic.

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#77

Post by iSnow »

beloch wrote: post #73

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 h…

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.

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#78

Post by mohawk »

beloch wrote: post #73

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 h…

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.

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#79

Post by plikan13 »

mohawk wrote: post #78
beloch wrote: post #73

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 h…

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.

Aside from waste storage there's also the cost of dismantling old reactors. The Wikipedia article on nuclear decommissioning makes for some depressing reading:

http://en.wikipedia.org/wiki/Nuclear_decommissioning

The tl;dr being "with a few notable exceptions, it's just too damn expensive so we just ignore the problem"

Re: Chernobyl’s Hot Mess, “the Elephant’s Foot,” Is Still Lethal (2013)

#80

Post by EliRivers »

illumen wrote: post #57
cjslep wrote: post #4

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 checkli…

They were doing things in their routine. Thus it's routine. You're misrepresenting things.

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.
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