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Hundreds Still Live In The 'Exclusion Zone' Around Chernobyl (bbc.com)
This weekend the BBC reports on the site of the Chernobyl nuclear plant explosion -- where "robotic cranes are dismantling 33-year-old, radioactive wreckage" -- investigating an area of more than 4,000 square kilometres [2,485 square miles] that's been abandoned since 1986. "That could be about to change..."
An anonymous reader summarizes their report: "Every community within a 30km radius [18.9 miles] of the plant was evacuated and abandoned; no one was allowed to return here to live." Yet the BBC visits a tiny community of 15 who reclaimed their homes in 1986 -- part of a population of 200 "self-settlers" deep in the exclusion zone, "an ageing population cut off from the rest of the country.... Almost every family forced to leave here was given an apartment in a nearby town or city. For Maria and her [88-year-old] mother, though, this cottage, with the garden wrapped around it, was home. They refused to abandon it. 'We weren't allowed to come back, but I followed my mum.'"
Parts of the exclusion zone in Ukraine and Belarus have become "a post-human nature reserve", home to prowling wolves and dozens of wild horses. Yet Professor Jim Smith from the UK's University of Portsmouth explains that "Most of the area of the exclusion zone gives rise to lower radiation dose rates than many areas of natural radioactivity worldwide." In fact, the abandoned nuclear-worker city of Pripyat was recently deemed safe to visit for short periods, "and has now become one of Ukraine's most talked about tourist attractions. An estimated 60,000 people visited the exclusion zone last year, keen to witness the dramatic decay."
And beyond the 18.9-mile line is Narodichi, a town of more than 2,500 people, where people "were quietly allowed to return home a few months after the disaster." Still considered an officially contaminated district -- and still in the "exclusion zone" -- it's a semi-abandoned area where all agriculture is banned, and the land can't be developed. 130 children attend Narodichi's kindergarten, but the kindergarten manager says half their parents are unemployed, "because there is nowhere to work." One of the least-contaminated areas in the exclusion zone, "Three decades of research have concluded that much of it is safe - for food to be grown and for the land to be developed." The BBC argues that "Fear of radiation could actually be hurting the people...far more than the radiation itself. "
An anonymous reader summarizes their report: "Every community within a 30km radius [18.9 miles] of the plant was evacuated and abandoned; no one was allowed to return here to live." Yet the BBC visits a tiny community of 15 who reclaimed their homes in 1986 -- part of a population of 200 "self-settlers" deep in the exclusion zone, "an ageing population cut off from the rest of the country.... Almost every family forced to leave here was given an apartment in a nearby town or city. For Maria and her [88-year-old] mother, though, this cottage, with the garden wrapped around it, was home. They refused to abandon it. 'We weren't allowed to come back, but I followed my mum.'"
Parts of the exclusion zone in Ukraine and Belarus have become "a post-human nature reserve", home to prowling wolves and dozens of wild horses. Yet Professor Jim Smith from the UK's University of Portsmouth explains that "Most of the area of the exclusion zone gives rise to lower radiation dose rates than many areas of natural radioactivity worldwide." In fact, the abandoned nuclear-worker city of Pripyat was recently deemed safe to visit for short periods, "and has now become one of Ukraine's most talked about tourist attractions. An estimated 60,000 people visited the exclusion zone last year, keen to witness the dramatic decay."
And beyond the 18.9-mile line is Narodichi, a town of more than 2,500 people, where people "were quietly allowed to return home a few months after the disaster." Still considered an officially contaminated district -- and still in the "exclusion zone" -- it's a semi-abandoned area where all agriculture is banned, and the land can't be developed. 130 children attend Narodichi's kindergarten, but the kindergarten manager says half their parents are unemployed, "because there is nowhere to work." One of the least-contaminated areas in the exclusion zone, "Three decades of research have concluded that much of it is safe - for food to be grown and for the land to be developed." The BBC argues that "Fear of radiation could actually be hurting the people...far more than the radiation itself. "
The average American gets 17 microsieverts per day. Most of the exclusion zone has way less than that.
Its amazing how many people are still surprised that it is perfectly safe to live in these areas. Its highly dissappointing that many of these are reporters. Years of FUD still has its power over established science.
It didn't happen by accident at Chernobyl. It happened by abject stupidity.
It wasn't. Unless you consider the mandate from Moscow to run that particular test "sabotage". The particular test in question was "is it possible to extract usable energy from a nuclear plant to deal with a meltdown in progress?" For which test, they pushed an out-of-the-way (in other words, on the back end of nowhere) nuclear plant as close to meltdown conditions as it was possible to safely go.
Unfortunately, they were wrong about how far "as it was possible to SAFELY go" was....
No, they weren't. They were doing experimental work prescribed by a bureaucrat several thousand km away. Which experimental work was completely unnecessary. The only good thing about the mess was that they had (barely) enough sense to do it on a reactor on the backend of nowhere...
Only to people who know little or nothing about them.
Remember, for all that Chernobyl was the worst nuclear power disaster in the history of the world, it killed fewer people than will die in traffic in the USA TODAY.
For that matter, hydroelectric power has killed three orders of magnitude (at least. the three orders of magnitude are from ONE incident) more people than nuclear power, much less coal....
"I do not agree with what you say, but I will defend to the death your right to say it"
Millions still live in New Jersey!
Is that a joke? I have to assume it is. Hiroshima ground zero is marked with a fairly small plaque on a boring standard Japanese side-street next to apartment buildings, businesses and restaurants. The one in Nagasaki is a small park with apartment buildings and a busy street about 150' away.
And to add to that, the only reason why Chernobyl was as hard to shut down properly as it was, was because that reactor type used graphite as a moderator. Graphite that burns, but keeps moderating in event of runaway reaction, which maintains the chain reaction.
Modern reactors used heavy water as moderator for a very long time. If reaction runs away, water evaporates, and therefore ceases moderating the reaction, which means reaction no longer has slow neutrons to continue the chain reaction. So in event of Chernobyl like runaway reaction in a heavy water reactor, it would stop itself very quickly due to lack of ability to maintain chain reaction.
The design of the plant at Chernobyl used a positive void coefficient. Basically, when the cooling water starts to boil (creating voids in the water), that increases the rate of nuclear fission. No western nuclear plant was ever designed like this because of how stupidly dangerous it is. All western nuclear plants use a negative void coefficient - the cooling water boiling slows down the rate of fission. An accident like Chernobyl could never happen at a western plant. The Soviets were trying to get energy for as cheap as possible and cut all sorts of corners designing their plants, including using a positive void coefficient .
Chernobyl began as a test where they intentionally shut down the automatic safety systems, then didn't react in time when the rate of fissioning began to go out of control. Due to the positive void coefficient design, once the boiling water began boiling, the heat generation began to increase exponentially. The fuel vaporized and exploded, blowing the reactor and containment building apart, and throwing radioactive debris and vapor into the atmosphere and countryside.
The accident at Three Mile Island was actually pretty similar in terms of buildup. They shut down a bunch of safety systems for a test, then didn't monitor the instrument readings closely enough (or more likely, the people monitoring them weren't trained well enough to understand what the readings meant - Homer Simpson as incompetent nuclear plant operator is actually a reference to TMI). The temperature went up, the cooling water boiled, and the fissioning stopped. The increased temperature was enough to melt the fuel rods, turning the reactor into useless slag. But it was all contained within the steel pressure vessel exactly like designed (there's a second reinforced concrete containment vessel around the pressure vessel in case it fails). The concern at the time was that a reaction between the fuel rod cladding and water had created hydrogen gas at sufficient pressure to crack both containment vessels, so they evacuated around the plant out of an abundance of \caution. But it turned out not to have been a concern as the hydrogen vented. It's a tiny molecule so can permeate through things that are designed to contain water and radioactive materials. (It's the reason the buildings at Fukushima blew apart. There's supposed to be a vent or fan which exhausts hydrogen into the atmosphere, but apparently that wasn't working at Fukushima so it built up until it reacted with atmospheric oxygen in an explosion that blew apart the exterior building. It did not affect the pressure vessel or the concrete containment vessel.)
The comparison I like to draw when people point to Chernobyl as an example of problems with nuclear power is Banqio. The worst power generation-related accident in history was actually the failure of a series of hydroelectric dams. During intense rain, a series of earthen dams used to hold water for generation at a hydroelectric power plant failed. The resulting flood and devastation killed about 170,000 people, destroyed nearly 6 million buildings, and left 11 million people homeless. But no western country uses earthen dams for hydroelectric power. So citing Banqio as an example of why hydroelectric power is dangerous and shouldn't be used, is like citing Chernobyl as an example of why nuclear power is dangerous and shouldn't be used. They're both irrelevant outside of the Communist bloc, since the rest of the world never did anything so stupidly dangerous.
Actually, at the time of the explosion, the operators were doing things FAR from standard, and in fact, the precipitating event was an operation explicitly prohibited under any circumstances in order to do something they weren't supposed to attempt.
More specifically, they were SUPPOSED to bring the reactor down to a low output and stabilize it there, then scram the reactor to see if residual steam and inertia in the system would provide sufficient power to safely shut it down. In order to do the test, several safeties were disabled.
The test was supposed to happen during the day shift, but high power demands meant they had to wait. This left the less experienced night crew to carry out the test. They probably should have postponed, but that would anger the (seriously dysfunctional) upper management.
First stem, they reduced power, but they reduced it too much. So they tried to bring power back up to the starting condition but the reactor wouldn't do it. This shouldn't have been a surprise, when reactor power is reduced by a large amount, the production of neutron absorbing poisons temporarily outstrips their "burn off" from excess neutrons. Rather than wait the prescribed 24-48 hours for the poisons to decay, they decided to attempt to burn off the poisons by withdrawing more control rods (a prohibited procedure)
Still having no success, they eventually withdrew ALL of the control rods (an absolutely forbidden procedure) leaving the reactor in a VERY unstable condition. In fact, it was primed for a runaway positive feedback. As power output started rising rapidly, they attempted to drive the conntrol rods back in, but it wasn't possible to do it fast enough, so the reactor went to many times it's maximum rating and then part of the core exploded (a flash steam explosion, not a nuclear explosion) and much of the core was ejected through the top of the reactor.
So it was an inherently dangerous reactor design, disabled safeties, and undertrained and inexperienced operators doing all the don'ts that resulted in the disaster.
The reactor's design was a big contributor as well. For one, it had a positive void coefficient. Meaning if the coolant formed a void, power output would increase. Reactor designs approved in the rest of the world tend to have a negative void coefficient. The control rods were (for some odd reason) carbon tipped, meaning that the first few feet of the rod INCREASE output by improving moderation. It had no actual containment building, just standard industrial sheet metal.
Can't have a big bang just because some suicidal terrorists fight their way into the reactor hall.
A safety feature I've seen proposed in some fourth generation designs is a big fat "fuck you" button for such a scenario. If there is a threat of release of anything even potentially weapons grade, or of sabotage, there is a mechanism that will dump a big load of fission poisoning isotopes to spoil the batch and render the core effectively inert. They might still be able to walk away with some radioactive material but it will be no more valuable in a weapon than natural uranium dug up from the ground. Mashing the "fuck you" button would render the power plant unable to be restarted for a very long time but it also makes it worthless to anyone that wants to use it to make weapons.
Any nation that wants to make a nuclear weapon can do so by digging up some uranium and enriching it like the USA did in the 1940s. All the anti-proliferation laws do is keep the bar at that level rather than lower it with access to some new technology.
I am armed because I am free. I am free because I am armed.
the environmental exposure is 2.4 to 3 mSv. A quick search on EPA for "17 micro Sv per day" reveal nothing, and all source I cited have that 3mSv. The only way I can get to 6 mSv per year is if you count *medical* exposure in addition to environmental.
While what you posting is sort of correct, it seems to lack any sort of understanding of background radiation. The first problem is that measuring radiation is really complex. Your unit of measure, the mSv is used for something called absorbed dose which takes into account things like how far you are from the radiation source and how quickly your body absorbs radiation. Its a measure of how much biological effect, but it isn't a measure of background radiation. We use Curries or Becquerels for that. The problem is that different types of ionizing radiation do different things and so have to be measured differently. Alpha radiation for instance can be blocked by clothes and sunscreen and is found in sunlight but does 20x the damage to the body per unit of energy so the amount of alpha radiation released is multiplied by 20 when calculating absorbed dose but not multiplied when calculating effective dose (a physical measure of an amount of radiation to which something was exposed)
As far as measuring the amount of radiation in an area, you can do that and everywhere around the world there is some background radiation. However, that amount varies wildly in a ratio of about 1:400. So there are natural places around the world where people have lived for >10,000 years which naturally have higher levels of background radiation than Chernobyl had just weeks after the accident (Congo, another in Iran, and in Brazil). Also, those places don't have higher than normal amounts of cancer which is weird. Also, flying will expose you to about 100x the radiation that you experience at the airport. And finally, you yourself and me and every other human ever born is slightly radioactive thanks to K40.
We just don't know the exact amounts and effects of high levels of radioactivity over time, but clearly the LNT (Linear no threshold) model we use is incorrect. But since using an overly cautious way to measure health effects is considered good, we do it. However, now that the fear of nuclear power is hurting us more than radiation ever could, perhaps that well-meaning decision (that the man who made the decision knew was overly cautious when he announced the theory) could be reevaluated. Maybe an acceptable level of radiation is a high background radiation found at naturally radioactive sites. Nah, the trial lawyers couldn't allow that...
"Those that start by burning books, will end by burning men."
But due to Q factor and other effect it is much easier to use mSv, Bq is nigh useless for example as 10 Bq of gamma or 10 Bq of alpha have vastly different effect from outside the organism or inside, but aside that you are speaking of *activity* which is not what the OP is about but absorbed dose. So if you want to go Rem or Gray feel free to do it, but environmental average exposure will mostly be cited in Sv again due to the fact we are more interested in equivalent absorbed dose, than what activity there is. And As you see above *the op cited in Sv therefore it makes sense to continue in Sv*. Furthermore I cited again the average and mentioned there are vast difference between where you are (my example was limoge due to the known radon problem there - but there are other known). Again none of your explanation pertain to the op which pretended that 17 micro Sv per day is average for environmental radiation in the US without cite (this is 6 mSv per year), and this run contrary to all cite I provided (which use absorbed dose Sv too). Not too be too snarky, but none of your explanation explain the OP nor do they offer cite for the OP. As for curie... It has been an eternity I had anybody speak to me in that unit when speaking of exposure or absorbed dose. Is that an US holdover ?
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