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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. "
You say this like it proves the exclusion zone is too big. In fact the problem with the exclusion zone is that it's not uniform; it has hot spots where you would not want to live, and less hot spots that you could live in and which are are closer to the sarcophagus.
You could reduce the area of the zone by producing an extremely detailed map of go/no-go areas. That has the advantage of reclaiming more land. But it has the disadvantage that given enough people living right next to no-go areas a certain number will inevitably stray into them, pick up or disturb contamination, then spread it.
No matter how you draw the line, you could probably draw it better by some criterion.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
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.