Exorcising the Demons of Chernobyl or Overcoming anti-Nuclear Hysteria

Why would an energy-craving nation (the U.S.) that also demands a pristine environment put the kibosh on a limitless form of power (nuclear energy) that produces no air pollution and no emissions environmentalists claim cause global warming?

It stems essentially from two massively-publicized incidents that plague our imagination: Three Mile Island in Pennsylvania in 1979 and especially Chernobyl in Ukraine. Nobody was even injured at TMI, but Chernobyl was a disaster of epic proportions. Or was it?

For the answer go back to 1986 in the former Soviet Union, a regime in which worker and public safety mattered zilch. A powerful steam explosion at one of four reactors of the Chernobyl nuclear facility near Kiev – a hunk of junk compared to any American nuke plant – caused additional explosions, a fire, and a full nuclear meltdown. Over 100,000 people were evacuated.

UPI's immediate death toll was 2,000 while others used far higher figures. "Late Word From Inside Russia: Mass Grave for 15,000 N-Victims," blared the New York Post. Blame these perhaps on confusion and Soviet secrecy. But in 2001 Agence France-Presse reported the highest toll ever, claiming "between 15,000 and 30,000 people died" from the initial blast and radiation exposure. As to delayed cancer deaths from radiation, some nuclear energy opponents estimated almost half a million.

But a voluminous new report assembled by the Chernobyl Forum, comprising 8 UN agencies, shows not only that the accident's immediate impact was grossly exaggerated but that even delayed cancer deaths will prove minuscule compared to the outrageous predictions.

The actual number of immediate deaths? Not 30,000 but rather 47 says the report. All were among plant personnel and emergency workers, none among the general public.

Delayed cancer deaths estimated in the new report? Not half a million but about 4,000. This though five million people received excess radiation exposure. Yet the report also admits that although there's been plenty of time for cancers to start showing up, researchers are having trouble finding enough cases even to justify the 4,000.

But even for the cancer most linked to radiation exposure (leukemia) and for those with the greatest such exposure (cleanup workers) it found studies repeatedly showing no increased risks.

Tragically, women as far away as southern Italy aborted their babies because of environmentalist propaganda essentially claiming they'd be born with three eyes and tentacles. Yet the report finds no evidence for excessive birth defects.

Indeed, "the largest public health problem created by the accident" is the "damaging psychological impact [due] to a lack of accurate information," the Chernobyl Forum found. "These problems manifest as negative self-assessments of health, belief in a shortened life expectancy, lack of initiative, and dependency on assistance from the state." As FDR might have put it, these poor people have nothing to fear but fear itself.

Never mind that accidents caused by natural gas, petroleum products, and accidents and black lung disease from coal take a steady toll of lives each year. Never mind that we're constantly bombarded with radiation from above (the sun) and below (the earth).

And never mind that even U.S. reactors designed four decades ago are incomparably safer than Chernobyl. Newer technologies such as "pebble bed reactors," in which the radioactive material is sealed in small graphite balls, are safer still.

Environmentalists think cheap food and housing are great, yet somehow affordable energy from any source is evil. Saintliness, to them, is achieved by paying through the nose for extravagantly inefficient power sources like windmills and solar panels.

Well, let them build a windmill in their backyards. The rest of us need an exorcism from the demons of anti-nuclear hysteria.

"And never mind that even U.S. reactors designed four decades ago are incomparably safer than Chernobyl. Newer technologies such as "pebble bed reactors," in which the radioactive material is sealed in small graphite balls, are safer still."

I don't know if the author realized when he wrote this article that the neutron irradiated graphite moderator caught fire in the Chernobyl reactor. While natural graphite is not flammable, when it is exposed to a neutron flux, it stores energy and becomes flammable (and even bulges). Saying that fuel in graphite balls is safer with the graphite being one of the most important items that allowed for the massive release of radiation at Chernobyl is a little silly.

Now I know that the 'pebbles' in pebble bed reactors are more than just fuel surrounded by graphite. But the author didn't say so. To a person who has actually operated nuclear reactors his statement stands out as fairly ridiculous. The graphite in the 'pebbles' has to do with neutron moderation, not with the prevention of the release of fission products.

Let me start off with that I’m pro-nuclear.

But this article is a pure load of BS!

To try to say it’s not that bad. is an injustice. The true magnitude of Chernobyl has yet to be stated.

I just happend to be reading this book now:

Voices from Chernobyl
http://www.centerforbookculture.org/dalkey/backlist/alexievich.html

It has some real horror stories in it.

One excerpt from a story told by a person drafted to aid in the clean up. He was the head of a chemical lab. So what did they have him do? They gave him a shovel. (bureaucrats
are the same everywhere) and was a worker striping off soil to be entomb. As he says;

They had protocols written that stated there was to be a geological survey, no ground water within 6 meters, not to deep and lined with polyethylene. But in real life it was
different. There was no survey, They’d point there finger and say “dig here” The excavator digs, “ how deep did you go?” “who the hell knows? I stopped when I hit water”

You just know that’s how it went. along with a number of other stories.

Nuclear energy along with these people. Need to be kept on a tight leash. A very tight leash.

There have been many close calls not to well known a few

Windscale Pile No. 1 at Sellafield north of Liverpool, England,

Chalk River, Canada

experimental SL-1 in Idaho Falls, Idaho,

Enrico Fermi 1 near Monroe, Michigan,
http://en.wikipedia.org/wiki/List_of_civilian_nuclear_accidents

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

To name a few

Elena's Motorcyle Ride through Chernobyl
http://www.kiddofspeed.com

Chernobyl info
http://www.chernobyl.info

I thought that the Chernobyl reaction stemmed from the graphite moderators breaking, hence a cessation of moderation.

Losing the moderator would have shut down the Chernobyl nuclear reaction. Unfortunately, since it was graphite it wasn't going anywhere until the core was breached.

Chernobyl stemmed from a large positive reactivity addition that was further amplified by a core having a positive void coefficient. Reactivity is the fractional change in neutron population per effective neutron generation. If reactivity is zero, there is no change per generation and since power is proportional to the neutron flux, power is constant. If reactivity is less than zero, power will decrease. If reactivity is greater than zero, power will increase. All of these follow an exponential law, so unless there is a mitigating factor, power will increase or decrease each generation by the same fraction. Additionally, if the reactivity is very high, it tends to decrease the effective neutron generation time. If the reactivity is phenomenally high, a condition called prompt criticality occurs; the neutron generation time is essentially only the time it takes to moderate the neutrons. A prompt critical reactor, like Chernobyl, will destroy itself.

What caused the prompt critical reaction is due to the the positive void coefficient in the reactor and the design of the control rods. A positive void coefficient means that with a separately moderated reactor (like Chernobyl), water acts as a neutron poison instead of a moderator. When neutrons hit the cooling water in this type of core, they effectively disappear from the reactor (a simplified description, obviously). If you create a void (a place where no water exists or water exists as steam), the probability that a neutron will go from one piece of fuel to another is increased. This increases reactivity, and is known as a positive void coefficient. So if your positive void coefficient designed reactor runs out of control and heats up rapidly boiling off water, it is only going to add more reactivity. This is what occurred in Chernobyl.

Second, the control rods in the Chernobyl reactor were designed with riders on the end of the control rods to make sure fueled burned more evenly. These tips have basically no effect on poisoning the reactor (in fact, they were made substantially out of graphite). While the rest of the control rod is a powerful neutron poison, these riders would add reactivity to the core for the first instant if the control rods were withdrawn all the way to the top and then inserted. This occurred.

I'm not going to go into the exact timeline of events or how the operators were stupid enough to place their reactor is such a dangerous configuration, though this page seems as good as any to describe those (note: it fails to describe the significance of the control rod insertion). I will say that at one point in time the increase in reactor power due to a mild level of voids in the reactor made the operators 'scram' the reactor. A reactor scram is where you insert all of the control rods fully to the bottom of the core in order to shut down the reaction. But as I described, the first instant the control rods were inserted they added positive reactivity. This further heated the reactor which began a runaway cycle (due to the positive void coefficient) that blew up the core.

One thing to note about most accounts on the web of the Chernobyl accident: only about 5% of the people have any clue on how to operate a nuclear reactor or the engineering and physics behind it. Many accounts are flat out wrong. Almost every account misses the importance of the reactor scram. Many miss the importance of the positive void coefficient.

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The Dutch switched from windmills to fossil fuels and nuclear power; environmentalists want us to switch from fossil fuels and nuclear power to windmills. (Photo by Michael Fumento)