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Engineering ethics, 8: case studies: chernobyl, three mile island.

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The Chernobyl Disaster: Public Responses

Pat yontrarak march 17, 2018, submitted as coursework for ph241 , stanford university, winter 2018, introduction.

April 26, 1986 marked the day of the most disastrous accident in the history of the nuclear industry: the Chernobyl reactor accident. Insufficiently trained workers, who violated several operating regulations. along with flawed reactor design, where damage to just 3-4 fuel assemblies would destroy the whole reactor, were major contributors to the catastrophe. [1] According to the United Nations Scientific Committee on the Effects of Atomic Radiation, UNSCEAR, the incident happened while carrying out a low-power engineering test of the Chernobyl Unit 4 reactor in the following sequence of events: the safety systems were switched off, the reactor was operated improperly, causing uncontainable power to be released, the reactor overheated, a series of explosions occurred, and the reactor was eventually completely destroyed. [2] As a result of the destruction of the Chernobyl 4 reactor, an array of radioisotopes were released for about 10 days, which caused extensive areas near the site to be exposed to radiation. This contamination lead to various medical, environmental, and economic issues that still affect the surrounding areas today. A photo of a radioactive sign at Chernobyl is shown in Fig.1.

Public Responses

Aside from visible impacts, the Chernobyl accident also affected the publics opinion on nuclear energy. According to a study, the level of opposition to nuclear power increased significantly after the incident in Finland, Yugoslavia, and Greece from around 30-40% to 60-75% in total; Austria, West Germany and Italy also faced considerable increments from around 45-60% to 70-80% in total. [3] Such evidence indicates that people from countries that are geographically located closer to the event had more significant psychological impacts and faced heightened fear. To support this notion, there was an observed relationship between the extent of perception change of a community and the level of radioactive contamination. [3] Perhaps, this was also due to peoples change in view of nuclear disasters as being more likely to occur than they previously thought. Therefore, it was not surprising that the proportion of citizens who were opposed to domestic nuclear programs spiked immediately after the accident, resulting in the government having to reevaluate these programs.

However, this rise in anti-nuclear sentiments was short-lived for some countries following the nuclear accident. According to a national survey, after the first year of the nuclear fallout, most people who were supporters of nuclear energy before the incident came to support these programs again. [4] This reversal in public perception was more prevalent for countries with strong nuclear programs, since people eventually became swayed by and found comfort in their communitys majority opinion that was favored towards using nuclear energy. This observation coincides with the attitude theory, which suggests that attitude changes will be temporary for indirectly- affected countries with low proportions of uncommitted responses to views on nuclear power prior to the fallout. [5] Although this may be the case, those who support domestic nuclear programs still expect revisions to policies including improving systems for emergency response in preparation for possible future accidents

Policy Adjustments

Following increased anti-nuclear sentiments and concerns regarding public safety of nuclear programs, most countries decided to adopt policy changes in their corresponding domestic nuclear programs and agreed on revised international policies. For instance, the Dutch parliament suspended plans to locate two additional nuclear reactors, Sweden confirmed its intentions of eliminating nuclear energy, and West Germany decided to set up a Federal Ministry for Environment and Reactor Safety. [4] From these examples, it appears that the fundamental nuclear policies of many of these countries were not altered since they were mostly geared towards the phasing out of nuclear energy already or that their decisions to not utilize nuclear power were strengthened. Also, there were countries that remained supportive of nuclear energy but their expansion plans were decelerated. Therefore, increased public concern caused governments to reconsider nuclear programs and revise safety protocols so that they were more stringent and ensured safety.

The Chernobyl catastrophe had disastrous effects on both the environment and humans, resulting in the public being immediately more fearful of and opposed to nuclear energy. These issues could have been alleviated through increased preparation for radioactive accidents beforehand, better handling of information regarding the accident, and strengthened international collaboration and transparency on these sensitive issues. [6] Even so, it lead to huge shifts in cooperation between industries and safety culture especially among directly affected countries, yielding some positive results from a catastrophic incident.

© Pat Yontrarak. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.

[1] Z. W. Seh, " Causes of the Chernobyl Accident ," Physics 241, Stanford University, Winter 2015.

[2] " Annex J: Exposures and Effects of the Chernobyl Accident ," in Sources and Effects of Ionizing Radiation - UNSCEAR 2000 Report to the General Assembly, Vol II (United Nations, 2000), pp 453 - 566.

[3] M. K. Lindell and R. W. Perry, "Effects of the Chernobyl Accident on Public Perceptions of Nuclear Plant Accident Risks," Risk Anal. 10 , 393 (1990).

[4] O. Renn, "Public Responses to the Chernobyl Accident," J. Environ. Psychol. 10 , 151 (1990).

[5] B. Verplanken, "Public Reactions to the Chernobyl Accident: A Case of Rationality?" Organ. Environ. 5 , 253 (1991).

[6] V. Saenko et al. , "The Chernobyl Accident and its Consequences," Clin. Oncol. 23 , 234, (2011).

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By: History.com Editors

Updated: April 23, 2021 | Original: April 24, 2018

Chernobyl is a nuclear power plant in Ukraine that was the site of a disastrous nuclear accident on April 26, 1986. A routine test at the power plant went horribly wrong, and two massive explosions blew the 1,000-ton roof off one of the plant’s reactors, releasing 400 times more radiation than the atomic bomb dropped on Hiroshima. The worst nuclear disaster in history killed two workers in the explosions and, within months, at least 28 more would be dead by acute radiation exposure. Eventually, thousands of people would show signs of health effects—including cancer—from the fallout.

The Chernobyl disaster not only stoked fears over the dangers of nuclear power, it also exposed the Soviet government’s lack of openness to the Soviet people and the international community. The meltdown and its aftermath drained the Soviet Union of billions in clean-up costs, led to the loss of a primary energy source and dealt a serious blow to national pride.

Then-Soviet leader Mikhail Gorbachev would later say that he thought the Chernobyl meltdown, “even more than my launch of  perestroika , was perhaps the real cause of the collapse of the Soviet Union five years later.”

Where Is Chernobyl?

Chernobyl is located in northern Ukraine, about 80 miles north of Kiev. A small town, Pripyat, was constructed a few miles from the site of the nuclear plant to accommodate workers and their families.

Construction of the Chernobyl power plant began in 1977, when the country was still part of the Soviet Union. By 1983, four reactors had been completed, and the addition of two more reactors was planned in subsequent years.

What Happened at Chernobyl?

A routine exercise to test whether an emergency water cooling system would work during a power loss started at 1:23 a.m. on April 26.

Within seconds, an uncontrolled reaction caused pressure to build up in Reactor No. 4 in the form of steam. The steam blasted the roof off the reactor, releasing plumes of radiation and chunks of burning, radioactive debris.

About two to three seconds later, a second explosion hurled out additional fuel. A fire started at the roof of Reactor No. 3, risking a breach at that facility. Automatic safety systems that would normally have kicked into action did not because they had been shut down prior to the test.

READ MORE:  Chernobyl Disaster: The Meltdown by the Minute

Firefighters arrived at the scene within minutes and began to fight the blaze without gear to protect them from radiation. Many of them would soon number among the 28 killed by acute radiation exposure.

Eyewitness accounts of the firefighters who had helped battle the fires described the radiation as “tasting like metal,” and feeling pain like pins and needles on their faces, according to the CBC documentary series, Witness . Days later, many of those firefighters would be dead.

It wasn’t until 5 a.m. the following day that Reactor No. 3 was shut down. Some 24 hours later, Reactors No. 1 and 2 were also shut down.

By the afternoon of April 26, the Soviet government had mobilized troops to help fight the blaze. Some were dropped at the rooftop of the reactor to furiously shovel debris off the facility and spray water on the exposed reactor to keep it cool.

The workers were picked up within seconds to minimize their radiation exposure. It would take nearly two weeks to extinguish all the fires using sand, lead and nitrogen.

Pripyat Evacuated

Meanwhile, life went on as usual for almost a day in the neighboring town of Pripyat. Aside from the sight of trucks cleaning the streets with foam, there were initially few signs of the disaster unfolding just miles away.

It wasn’t until the next day, April 27, when the government began evacuations of Pripyat’s 50,000 residents. Residents were told they would be away for just a few days, so they took very little with them. Most would never return to their homes.

Soviet Secrecy

It took days for Soviet leadership to inform the international community that the disaster had occurred. The Soviet government made no official statement about the global-scale accident until Swedish leaders demanded an explanation when operators of a nuclear power plant in Stockholm registered unusually high radiation levels near their plant.

Finally, on April 28, the Kremlin reported that there had been an accident at Chernobyl and that authorities were handling it. The statement was followed by a state broadcast detailing the U.S. nuclear accident at Three Mile Island and other nuclear incidents in western countries.

Three days later, Soviet May Day parades to celebrate workers went ahead as usual in Moscow, Kiev and Belarus’ capital Minsk—even as hazardous amounts of radiation were still streaming from the wrecked power plant.

Most people, even within the Ukraine, were still unaware of the accident, the deaths, and the hasty evacuations of Pripyat.

READ MORE: The Chernobyl Cover-Up: How Officials Botched Evacuating an Irradiated City

Chernobyl Disaster Spewed Radiation

The damaged plant released a large quantity of radioactive substances, including iodine-131, cesium-137, plutonium and strontium-90, into the air for over a period of 10 days.

The radioactive cloud was deposited nearby as dust and debris, but was also carried by wind over the Ukraine, Belarus, Russia, Scandinavia and other parts of Europe.

In an attempt to contain the fallout, on May 14, Soviet leader Mikhail Gorbachev ordered the dispatch of hundreds of thousands of people, including firefighters, military reservists and miners, to the site to aid in clean-up. The corps worked steadily, often with inadequate protective gear, through 1989 to clear debris and contain the disaster.

Chernobyl Sarcophagus

Over a hurried construction period of 206 days, crews erected a steel and cement sarcophagus to entomb the damaged reactor and contain any further release of radiation.

As former liquidator, Yaroslav Melnik, told the BBC in January 2017, “We worked in three shifts, but only for five to seven minutes at a time because of the danger. After finishing, we’d throw our clothes in the garbage.”

Starting in 2010, an international consortium organized the building of a bigger, more secure sarcophagus for the site. The 35,000-ton New Safe Confinement was built on tracks and then slid over the damaged reactor and existing sarcophagus in November 2016.

After the installation of the new structure, radiation near the plant dropped to just one-tenth of previous levels, according to official figures. The structure was designed to contain the radioactive debris for 100 years.

Chernobyl Elephant’s Foot

Deep within the basement of Reactor 4 lies the Chernobyl Elephant’s Foot, a huge mass of melted concrete, sand and highly radioactive nuclear fuel.

The mass was named for its wrinkled appearance, which reminded some observers of the wrinkled skin of an elephant’s leg and foot.

In the 1980s, the Elephant’s Foot gave off an estimated 10,000 roentgens of radiation each hour, enough to kill a person three feet away in less than two minutes. By 2001, that rate had dropped to roughly 800 roentgens per hour.

How Many People Died in Chernobyl?

Ukraine’s government declared in 1995 that 125,000 people had died from the effects of Chernobyl radiation. A 2005 report from the United Nations Chernobyl Forum estimated that while fewer than 50 people were killed in the months following the accident, up to 9,000 people could eventually die from excess cancer deaths linked to radiation exposure from Chernobyl.

As of 2005, according to the Union of Concerned Scientists , some 6,000 thyroid cancers and 15 thyroid cancer deaths had been attributed to Chernobyl.

Health effects from the Chernobyl disaster remain unclear, apart from the initial 30 people the Soviet government confirmed killed from the explosions and acute radiation exposure. No official government studies were conducted following the explosion to assess its effects on workers, the liquidators and nearby populations.

A 2011 study by the U.S. National Institutes of Health concluded that exposure to radioactive iodine-131 from Chernobyl fallout was likely responsible for thyroid cancers that were still being reported among people who were children or adolescents at the time of the accident.

Chernobyl Exclusion Zone

Apart from the ever-unfolding human toll from the disaster, the Chernobyl accident also left behind a huge area of radiation-tainted land.

A 770-mile-wide Chernobyl Exclusion Zone around the site isn’t considered safe for human habitation and can’t be used for logging or agriculture due to contaminated plants and soil. By 2017, however, entrepreneurs found a new use for the territory.

In December 2017, a Ukrainian-German company, Solar Chernobyl, announced construction of a massive solar power plant in the abandoned territory. The one-megawatt power plant, built just a few hundred feet from the damaged Reactor 4, was fitted with 3,800 photovoltaic panels. The Ukrainian government said that a collection of companies planned to eventually develop up to 99 more megawatts of solar power at the site.

That’s a lot of power, but still not close to the former output of the ruined nuclear power plant. At the time of the accident Chernobyl’s four reactors could generate 1,000 megawatts each .

Chernobyl Animals Thrive

Meanwhile, wildlife, including boars, wolves, beavers and bison, showed signs of flourishing at the Chernobyl site, according to an April 2016 study .

The researchers pointed out that while radiation exposure couldn’t be good for the animals, the benefits of the absence of humans outweighed radiation risk.

Chernobyl Today

Humans, on the other hand, aren’t expected to repopulate the area any time soon. Ukrainian authorities have said it will not be safe for people to live in the Chernobyl Exclusion Zone for more than 24,000 years.

Today tourists can visit the site, which appears frozen in time, apart from signs of looting, natural weathering and the encroachment of nature.

“Chernobyl: The True Scale of the Accident,” September 5, 2005, World Health Organization . Chernobyl Accident 1986, updated November 2016, World Nuclear Association “Health Effects of the Chernobyl Accident: An Overview,” April 2006, World Health Organization . “Chernobyl’s Legacy 30 Years On,” by Tom Burridge, April 26, 2016, BBC News “Higher Cancer Risk Continues After Chernobyl,” March 17, 2011, National Institutes of Health . “How Many Cancer Deaths Did Chernobyl Really Cause?” by Lisbeth Gronlund, Union of Concerned Scientists . “Animals Rule Chernobyl Three Decades After Nuclear Disaster,” by John Wendle, April 18, 2016, National Geographic . “A Nuclear Disaster That Brought Down an Empire,” April 26, 2016, The Economist . “World’s Largest Moveable Steel Structure Shelters Sarcophagus at Chernobyl,” April 27, 2017, PhysOrg/Pacific Northwest National Laboratory . “Pictures: ‘Liquidators’ Endured Chernobyl 25 Years Ago,” by Marianne Lavelle, April 27, 2011, National Geographic . “Chernobyl: Timeline of a Nuclear Nightmare,” by Kim Hjelmgaard, USA Today . “A Vast New Tomb for the Most Dangerous Disaster Site in the World,” by Christian Borys, January 3, 2017, BBC Future Now . “The Lessons of Chernobyl May Be Different Than We Thought,” by Ryan Faith, April 26, 2016, Vice News . “25 Years After Chernobyl, We Don’t Know How Many Died,” by Roger Highfield, April 21, 2011, New Scientist . “Chernobyl’s Transformation Into a Massive Solar Plant Is Almost Complete,” by David Nield, January 13, 2018, Science Alert . “The Famous Photo of Chernobyl’s Most Dangerous Radioactive Material Was a Selfie.” January 24, 2016, Atlas Obscura .

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Chernobyl accident summary

Chernobyl accident , Accident at the Chernobyl (Ukraine) nuclear power station in the Soviet Union, the worst disaster in the history of nuclear power generation. On April 25–26, 1986, technicians attempted a poorly designed experiment, causing the chain reaction in the core to go out of control. The reactor’s lid was blown off, and large amounts of radioactive material were released into the atmosphere. A partial meltdown of the core also occurred. A cover-up was attempted, but, after Swedish monitoring stations reported abnormally high levels of wind-transported radioactivity, the Soviet government admitted the truth. As many as 49 people may have died in the initial explosions. Beyond these immediate deaths, several thousand radiation-induced illnesses and cancer deaths were expected in the long term. The incident set off an international outcry over the dangers posed by radioactive emissions.

Chernobyl Nuclear Plant Disaster Case Study

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Case Summary

Causes of disaster, effects of the calamity, health effects, list of references.

This catastrophe happened at a nuclear powered station in one of the Ukrainian regions called Chernobyl, on April 26,1986. The disaster led to a prolonged discharge of enormous quantities of radioactive materials into the atmosphere across Europe. Nevertheless, Canada, USA, and Japan also recorded some contamination.

After the disaster, only the Southern Hemisphere remained free of this pollution (Nuclear Energy Agency 2002). The disaster occurred during a short-term closure of the power station for routine repairs. During the momentary closure, the maintenance team decided to carry out several tests on the reactor, but made numerous mistakes such as failing to maintain an optimum electric power and cooling of the RBMK reactor.

These mistakes caused several explosions that destroyed major components of the reactor leading to leakage of radioactive components into the environment (Nuclear Energy Agency 2002).

A series of events led to the 1986 Chernobyl disaster, which culminated to several major explosions and contaminations. The investigation team on the Chernobyl accident established the four major causes of the disaster, which comprised communication failures, architectural errors in RBMK nuclear reactor, violation of technical guidelines, and the lack of safety principles at the station (World Nuclear Association 2012).

These issues led to several unexpected chemical reactions inside the reactor, which later triggered several explosions, and an enormous fireball that destroyed the thick concrete and fortified lid of the reactor.

The Chernobyl calamity made news headlines in 1980s because of its magnitude and impacts on several aspects of human living. The Chernobyl disaster’s consequences consisted in health, environmental, political, social, economic, and psychological issues.

The environmental effects of the disaster were attributed to radioactive materials. The explosion dispersed radioactive components over a large geographical area causing radioactive contamination of the soil (Czirják, Møller, Mousseau, & Heeb 2010). The fallout affected the Northern hemisphere in several ways.

For instance, in numerous areas within a 10km distance from the nuclear station, the radiation caused fatally high levels of contamination, particularly in small animals such as rats and mice (Czirják, Møller, Mousseau, & Heeb 2010).

The active elements released into the environment have caused adverse health effects on residents of Ukraine, and other people in affected areas across the Northern Hemisphere. Since the disaster, the reported prevalence of thyroid cancers among Ukrainian youth aged 1-15 years old has increased. Before the disaster the average prevalence of thyroid melanoma was 5/1,000,000, but after the year 1986 it increased up to 45/1,000,000.

Most incidents of thyroid melanoma happened in areas neighbouring the nuclear plant, for instance, Kiev and Cherkassy. Other types of malignancy have also been reported in areas that received high levels of contaminants, and among people who helped during the clean-up process (Ivanov, Chekin, Kashcheev, Maksioutov, & Tumanov 2008).

The other outcome of the disaster encompassed psychological issues. Following the disaster, psychosomatic conditions such as stress, apprehension, and other mental traumas increased twice or even thrice.

These conditions did not result from the radiation leak, but from the anxiety of emergency evacuation, fears that the future generations might be affected by the radiation, and the secrecy surrounding the causes of the disaster.

Finally, the disaster in Chernobyl led to political, economic, and social problems in terms of the reduced birth rates and increased emigration. These aspects have led to unavailability of workers leading to slow industrial growth in such fields as agriculture and exportation. Moreover, radioactive contaminants reduced available agricultural land, and the food cultivated in Chernobyl cannot be sold because people fear to take it.

Czirják, G, Møller, P, Mousseau, T, & Heeb, P 2010, ‘Associated with Feathers of Barn Swallows in Radioactively Contaminated Areas around Chernobyl’, Microbial Ecology, vol. 60 no. 2, pp. 373-80.

Ivanov, K, Chekin, S, Kashcheev, V, Maksioutov, M, & Tumanov, K 2008, ‘Risk of thyroid cancer among Chernobyl emergency workers of Russia’, Radiation and Environmental Biophysics , vol.47 no. 4, pp. 463-7.

Nuclear Energy Agency 2002, Chernobyl: Assessment of Radiological and Health Impact . Web.

WorldNuclear Association 2012, Chernobyl Accident 1986 . Web.

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IvyPanda. (2019, June 17). Chernobyl Nuclear Plant Disaster. https://ivypanda.com/essays/the-chernobyl-disaster/

"Chernobyl Nuclear Plant Disaster." IvyPanda , 17 June 2019, ivypanda.com/essays/the-chernobyl-disaster/.

IvyPanda . (2019) 'Chernobyl Nuclear Plant Disaster'. 17 June.

IvyPanda . 2019. "Chernobyl Nuclear Plant Disaster." June 17, 2019. https://ivypanda.com/essays/the-chernobyl-disaster/.

1. IvyPanda . "Chernobyl Nuclear Plant Disaster." June 17, 2019. https://ivypanda.com/essays/the-chernobyl-disaster/.

Bibliography

IvyPanda . "Chernobyl Nuclear Plant Disaster." June 17, 2019. https://ivypanda.com/essays/the-chernobyl-disaster/.

Chernobyl Disaster

On the morning of 26th April, 1986, the unit 4 reactor at the Chernobyl Nuclear Power Plant in Pripyat, Ukraine exploded, releasing large amounts of radiation in the surrounding region. Ukraine was part of the Soviet Union then, which would have long-term consequences for the super-state in the years to come.

Along with the Fukushima Reactor Incident in Japan, The Chernobyl  Disaster is the worst nuclear disaster to have occurred.

Now with the Russian invasion of Ukraine in full swing, the fate of the Chernobyl power plant hangs in the balance as the Russian army had surrounded the perimeter of the plant on 24th February 2022, preventing maintenance work from continuing.

For now this article will give details of the timeline of the events that took place on that fateful day as well as the impact of the disaster within the context of the IAS Exam .

Chernobyl Disaster- Download PDF Here

Timeline of the Chernobyl Disaster

• On April 25, 1986, the Chernobyl Power plant had reached 50% capacity in power generation. When another power plant in the region went offline, a request was made in the afternoon of April 25 and further power down was allowed after 10 PM.
• At 12:05 AM on April 26, the power was at around 23%. 30 minutes later the power fell to a near-zero level, probably due to a change of regulator.
• At 01:00 the power stabilized to 6% and it was decided that the test would be run at that level.
• Everyone went to their instruments and at 01:23:04 the turbine generator run down test began. Everything went completely normal.
• At 01:23:40 the Senior Reactor Chief Control Engineer L.F. Toptunov pressed the  emergency shutdown button as planned to end the test.
• Instead of the plant shutting down, there was a power surge which jumped from 7% to 17%. The power surge continued beyond normal levels as a result, the automatic control rods suffered damage and they chammed.
• At 01:23:47 AM, the fuel channels ruptured and the reactor exploded.

What was the cause of the Chernobyl Reactor Explosion?

The reactor had several design flaws which made the reactor unstable to begin with at the time of the test. The interaction of hot fuel with the cooling water led to fragmentation in the fuel along with rapid steam production causing pressure to build up.

The pressure build up caused the 1000 tons cover plate of the reactor to become detached, rupturing fuel channels and jamming the control rods. The intense steam generation spread through the entire core, which was fed by water dumped due to the rupture of the emergency cooling mechanisms. This caused a steam explosion and released fission products into the air.

A few seconds later, a second explosion blasted fragments from the fuel tower. These fragments included hot graphite which was lethal to touch.

Impact of the  Chernobyl Disaster

The accident resulted in the largest radioactive release into the environment ever recorded . large quantities of radioactive dust was released into the atmosphere for 10 days, which would have adverse social and economic effects for the populations of Belarus, Ukraine and Russia.

All the xenon gas, half of iodine, caesium, 5% of remaining radioactive material was released in the incident. The released material was carried by dust and debris but the remaining lighter material was carried over by winds to Russia, Belarus and to some extent Scandinavia and rest of Western Europe

The town of Pripyat in its entirety was evacuated on 27 April. About 45,000 residents were relocated to safe-zones. By 14  May about 116,000 people who were within a 30-kilometre radius had been evacuated. A few of these returned to unofficially live within the contaminated zone with adverse effects to their health.

Following the disaster, more than 220,000 people were resettled into safe zones which had little to no contamination. The initial Chernobyl exclusion zone of 30 kms was further extended to cover 4300 square kilometres. The extension of the safe zone was to protect from the extensive radiation that had blanketed the region.

Frequently Asked Questions about Chernobyl Disaster

What caused the chernobyl disaster, is chernobyl still active, how many people died in the chernobyl accident.

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Thirty-Five Years Later, a First Responder at the Chernobyl Disaster Looks Back

In her new book, Alla Shapiro shares her experience of one of the worst nuclear disasters in history

Jennifer Nalewicki

Travel Correspondent

April 26, 1986, started off like any other day for Alla Shapiro. The pediatrician, then 32 years old, was at work in the Pediatric Hematology Unit at the Children’s Hospital in Kiev, Ukraine. But everything changed when she learned that an explosion had occurred 80 miles north at the Chernobyl Nuclear Power Plant , just outside the city of Pripyat. In the hours that followed, hundreds of children arrived at the hospital by bus seeking treatment.

As a front-line worker, it was the first time that Shapiro and her colleagues were faced with treating patients during a disaster of Chernobyl's magnitude. Unfortunately, the Soviet government didn’t have any nuclear disaster protocols in place, and basic supplies were severely limited, leaving medical professionals to improvise and adapt. In the days and weeks that followed, Shapiro discovered that the government was misleading the public about its handling of the explosion, which was caused by a flawed reactor design, according to the World Nuclear Association .

The explosion occurred at 1:23 a.m. during a routine maintenance check of the plant's electrical system, when operators went against safety protocols and shut down parts of the control system that were necessary to run the plant safely. The result was an unexpected sudden surge in power due to excess steam building up in one of the reactors. The accident killed two plant workers immediately, but soon dozens more would perish from acute radiation sickness , including emergency workers and firefighters who were sent to the scene. Over the years, thousands of people would succumb to radiation contamination from the explosion, with the number of total deaths unknown since many people died years and decades after the fact. Cancer, particularly thyroid cancer , would become a common link among survivors, including Shapiro, who, now in her late 60s, is a cancer survivor herself. A pproximately 20,000 cases of thyroid cancer were registered from 1991 to 2015 in regions affected by the Chernobyl accident, according to a report published by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The high numbers are due to the fallout from the explosion, with winds carrying toxic particles as far away as Switzerland .

Doctor on Call: Chernobyl Responder, Jewish Refugee, Radiation Expert

Dr. Alla Shapiro was a first physician-responder to the worst nuclear disaster in history: the explosion at the Chernobyl Nuclear Power Station in Ukraine on April 26, 1986. Information about the explosion was withheld from first responders, who were not given basic supplies, detailed instructions, or protective clothing. Amid an eerie and pervasive silence, Dr. Shapiro treated traumatized children as she tried to protect her family.

On the tragedy’s 35th anniversary, Shapiro shares her story from the frontlines of Chernobyl in a new book called Doctor on Call: Chernobyl Responder, Jewish Refugee, Radiation Expert . In her memoir, Shapiro discusses not only the disaster, but also her experience immigrating to the United States with her extended family and her work as a leading expert at the U.S. Food and Drug Administration in developing medical countermeasures against radiation exposure. Her work is a testament to the importance of preparedness, especially in the face of adversity. Even now in retirement, Shapiro continues to work tirelessly in strengthening the preparedness of the United States against nuclear disaster. She's currently a consultant and an advisory board member for Meabco A/S, an international pharmaceutical company, that's developing a novel drug that could potentially protect humans from harmful doses of radiation. She's also conducting webinars for scientists and medical care providers who are interested in the health effects of radiation on humans.

Shapiro spoke with Smithsonian about her personal experience during one of the worst nuclear disasters in history, the Soviet government’s failure to act swiftly and transparently during the catastrophe, and her thoughts on the handling of the Covid-19 pandemic today.

What was going through your head as hundreds of children arrived at your hospital for treatment after the Chernobyl explosion?

I really didn’t have time to get scared or to get prepared. We saw the children arriving in a panic and in tears. It was a stressful event, but you have to act and do what you have to do. The negative thing was that we didn’t have any instruction, knowledge or training in radiation, so we exercised our [medical] background and did what we could. We also didn't have enough supplies and proper protective clothing to wear during examinations.

Since a similar disaster was never recorded in medical history books, and there were no guidelines in place for how to handle the situation, you had to innovate. Can you give an example of how you improvised?

We tried to comfort the children. It was only much later that we learned the psychological impact [of the disaster]. We told them funny stories and hugged them, which worked quite well. And then we looked at what we were facing—if children were coughing, at first we didn’t know why. In pediatrics, if a patient has a cough, most likely a fever will follow, but not in this case. We soon realized that the cough wasn’t related to any virus or infection. It was because the children were lacking oxygen, and their lungs were plugged with dust that possibly contained radiation particles. Many of the children waited outside for hours for the buses to arrive to bring them to the hospital. There were a lot of mistakes made [in the aftermath of the disaster], but one of the biggest was the lack of knowledge and understanding, [which resulted in] children being left outside to breathe this radioactive air. So, we started giving them oxygen. Since we didn’t have enough [individual oxygen tanks] for everyone, we made tents out of bed sheets and pumped oxygen in and had the children sit inside the tents.

The Soviet government withheld information pertaining to the explosion and its aftermath, and even spread rumors about the situation. How did this affect you?

It was very hard psychologically, especially knowing that some of the information being spread came from either government officials or through rumors. Lots of people, physicians in particular, have colleagues in different locations [that were sharing information with one another]. A close friend of mine was called into work on a Saturday, which was unusual for him. He was handed a dosimeter, the device used to measure [ionizing] radiation, and used it to measure the levels in tap water. He called me and told me not to use the tap water, not even to brush my teeth. It was nothing official, since he wasn’t allowed to tell anyone about his findings. I immediately shared this information with friends and colleagues. This is how information spreads despite all the warnings given [by the government] if you tell the truth. It was a huge risk for him to do what he did; he could’ve lost his job.

You often faced anti-Semitism as a Jewish doctor, which ultimately led to you immigrating with your family to the United States. What was that transition like coming here?

It wasn’t difficult for me, because I was by default so fond of [the United States]; I wanted to get here so badly. Plus, our family got an extremely warm welcome from the Jewish community when we arrived in Washington, D.C. We made friends in a couple of weeks, and quite a few of them are still some of our best friends. The welcoming we received took some fears off my mind, although not having a job and not having the credentials that would allow me [to practice medicine here], plus taking care of a little girl and my elderly grandmother, all contributed to my anxiety and uncertainty. Not every family had this kind of welcome. Some [refugee] families ended up in the far west where locals weren’t so familiar with immigrants and how to accept them and even if they should accept them. There was a fear that they would take their jobs. However, we were blessed, and we never wanted to leave Washington, D.C.; I considered it home from day one.

As a medical professional, how did your experience in Chernobyl prepare you for your work with the FDA developing disaster readiness protocols?

This experience taught me a lot. The main point is that people—not just physicians, but the general public—need knowledge of what’s happening. Unfortunately, in [the United States], physicians don’t have good and proper training in radiation. Without knowledge in this field, people can’t do anything, but fortunately we do have experts in the area of radiation. When I worked with the FDA, I had meetings with the Departments of Defense and Health and Human Services on how to prepare our country in case of a nuclear disaster. There are guidelines and [mock explosion] exercises that take place every other year that pretend that a nuclear explosion occurs in a major city. What I witnessed [at Chernobyl] helped me realize that strong communication between the government and the public and doctors is necessary, otherwise it can cause bad outcomes.

You compare the U.S government’s lack of preparedness during the Covid-19 pandemic to the Soviet Union’s mishandling of the Chernobyl explosion. What do think can be learned from both of these two global tragedies?

We need to analyze very critically what happened and why. Each disaster, regardless of whether it’s nuclear or a viral pandemic, has lots of things in common, and we need to be aware of this. There needs to be strong communication not only within the country, but also amongst international communities. So much depends on our preparedness, and so many deaths could’ve been avoided at Chernobyl. And the same with Covid-19. The former Soviet Union didn’t know how to prepare for such a disaster. The United States did know how to prepare, but failed to do it.

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Jennifer Nalewicki is a Brooklyn-based journalist. Her articles have been published in The New York Times , Scientific American , Popular Mechanics , United Hemispheres and more. You can find more of her work at her website .

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A new sarcophagus

“we will have more accidents”, uncertain consequences, mental health matters, ecological studies, public trust, what can chernobyl teach us.

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Toni Feder; What can Chernobyl teach us?. Physics Today 1 April 2016; 69 (4): 24–27. https://doi.org/10.1063/PT.3.3133

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Thirty years ago this month, on 26 April 1986, Reactor 4 at the Soviet-run Chernobyl Nuclear Power Plant exploded when operators undertook a safety experiment. The nuclear accident remains the worst to date, although debate and controversy surround the extent and types of damage incurred—from cancers to ecological impact to the effects of mass evacuations on communities and individuals.

Today the site, some 100 km north of Ukraine’s capital of Kiev and near the border with Belarus, is buzzing with activity. Two major construction projects are under way: a “new safe confinement” structure for the destroyed reactor, which remains highly radioactive, and a concrete spent-fuel storage facility. In addition, Ukrainian authorities are overseeing the decommissioning of the plant’s other three reactors, the last of which stopped operating in 2000; the process will take decades and cost billions of dollars. Much of the exclusion zone, the area within a roughly 30 km radius around the power plant, is abandoned and overgrown.

Enough time has passed that about half of the released cesium-137 and strontium-90 has decayed, but half remains; plutonium and other long-lived nuclides will continue to contaminate the area for millennia. Radiation levels in the exclusion zone soil vary, with highs mostly around 8–10 MBq/m 2 but at some spots reaching 200 MBq/m 2 , according to Sergiy Dubchak, an associate professor at the State Ecological Academy of Postgraduate Education and Management in Kiev. Staying in areas with 8–10 MBq/m 2 for a year corresponds to an annual exposure of about 175 mSv, he says. That’s roughly equivalent to a dozen CT scans. The exposure in the worst spots would be equivalent to nearly one scan a day.

The city of Pripyat, just 3 km from the disaster site, remains abandoned . And the town of Chernobyl, about 15 km from the power plant, provides temporary housing for workers on the building projects.

An iconic symbol of the Chernobyl disaster, this Ferris wheel is in the nearby city of Pripyat in an amusement park that never opened.

A pilot project to grow canola for biofuel started a few years ago; the crops would both produce fuel and, by accumulating radioactive nuclides, help detoxify the soil. There is talk about turning part of the exclusion zone into a wildlife preserve. A couple hundred people returned to live in their homes within the exclusion zone. And the zone has become a popular destination for disaster tourism.

Over the past decade or so, and especially since the 2011 nuclear accident in Fukushima, Japan (see Physics Today , November 2011, page 20 ), research has intensified in matters related to nuclear accidents, and in preparedness for and response to them. “The lessons of Chernobyl were not internalized in the West until Fukushima,” says Jan Beyea, chief scientist at the Lambertville, New Jersey–based Consulting in the Public Interest. Beyea served on a National Academy of Sciences committee that in 2014 reported on lessons learned from the Fukushima nuclear accident. “You have more attention now to what can be learned,” he says.

The concrete and steel structure currently enclosing the destroyed reactor at Chernobyl was completed quickly—206 days after the accident. It had a design lifetime of 25 years. Today the protective structure is crumbling; its roof partly collapsed in 2013. The new confinement sarcophagus , a 29 000-ton steel arch that is roughly 110 m tall, 160 m long, and 260 m wide at the base, is scheduled to be installed next year. It is designed to stop incursions of water and snow, prevent release of radioactivity, and provide a shelter for decommissioning the destroyed reactor; it will house two cranes that can each lift up to 50 tons.

A new safe confinement sarcophagus (left) is being built about 300 meters from the destroyed reactor (right); the sarcophagus is scheduled to be slid over the reactor next year. The memorial was erected a few years after the disaster.

According to the European Bank for Reconstruction and Development (EBRD), the shelter cost comes to €1.5 billion ($1.6 billion), plus €600 million in associated costs, such as preparing the site, installing monitoring and surveillance systems, and constructing a changing facility for workers. The European Commission is contributing €450 million; of the 45 countries that are pitching in, the US is covering €295 million, and Ukraine, Germany, France, the UK, and Japan are putting in amounts ranging from €185 million to €85 million.

The other major project at the site is a storage facility for the plant’s spent fuel. The estimated cost is €400 million, according to the EBRD. Some 20 000 spent-fuel assemblies need to be moved to dry storage from their current pools, where they are starting to corrode. After years of delays, design problems, and a change in contractors, the facility is supposed to be completed late this year.

For a long time, the prevailing view in the West was that a Chernobyl-scale event couldn’t happen there. The thinking was that the accident was due to a faulty Russian reactor design, poor training, and a corrupt Soviet system, says Sonja Schmid, a faculty member in science and technology studies at Virginia Tech. But, she says, the Soviets “were competitive and at the same level [as the West] in skills and expertise, so why would they choose a reactor design that was manifestly bad?”

After the Fukushima disaster, the dismissive logic no longer held up. “We will have more accidents. What do we do?” she says. “Fukushima has changed a lot to the better, in terms of learning from both accidents.”

As examples, Schmid notes that after the Fukushima disaster, many countries conducted risk and safety assessments of their nuclear reactors. And policymakers and power-plant regulators in different regions intensified talks about coordinating responses to any future accident. Last year France instituted a program whereby reactor operators are trained to respond to a nuclear emergency.

One lesson learned from both the Chernobyl and Fukushima disasters is to weigh the risks of evacuation against those of radiation, says Clemens Walther, director of the Institute for Radioecology and Radiation Protection (IRS) at Leibniz University in Hanover, Germany. “The evacuation should have been faster at Chernobyl. It was done better by the Japanese.” Still, better preparation, including for evacuating the elderly, sick, children, and their caretakers, would reduce fatalities. “A lot of elderly people died after the evacuation; for them there was no radiation-induced cancer risk due to old age.”

Among the first responders to the Chernobyl explosion, the official immediate death toll was 28, with another 134 suffering acute radiation syndrome. The total number of people who have or will become sick in the ensuing years from radiation exposure is impossible to pin down; estimates range from a few thousand to hundreds of thousands.

The best-documented sickness caused by Chernobyl is cancer of the thyroid gland, which takes up iodine to make metabolism-regulating hormones. Even though it was known that nonradioactive iodine could saturate the thyroid and minimize uptake of radioactive iodine, iodine was not efficiently distributed after either Chernobyl or Fukushima. In the 20 years after Chernobyl, more than 6000 cases of thyroid cancer in children and adolescents were attributed to radiation exposure, according to the United Nations Scientific Committee on the Effects of Atomic Radiation. Numbers are hard to come by for other health problems. Indeed, says Beyea, “the changes in occurrence are expected to be small compared to background, but you can project that there will be some excess cancers.”

Kate Brown, a science historian at the University of Maryland, Baltimore County, is among those who have reported increased medical problems of many sorts due to radiation exposure from Chernobyl. Because medicine was socialized in the Soviet Union, state clinics treated everyone, and they sent quarterly reports to headquarters, she says. “They had always done that, and they continued.” In sifting through doctors’ notes in the Ukrainian archives, she found patterns that started with chronic tonsillitis, gastritis, ulcers, and bronchitis. Solid cancers appeared later—of the thyroid, throat, lip, oral cavities, and stomach—followed by reproductive issues, including a big jump in birth defects, premature births, and babies who died within six months.

Such findings remain controversial. Walther, for example, says there is little evidence of “statistically meaningful hereditary effects among Chernobyl victims” and warns against confusing the effects of radiation with effects uncovered by increased screening and malnutrition.

The psychological impact of radiation exposure is increasingly viewed as one of the greatest health consequences of Chernobyl and Fukushima. “People feel sick, and believe their ills are caused by radiation exposure, even when their actual exposure was very low,” says Johan Havenaar, a Dutch psychiatrist who in the decade or so after Chernobyl focused his research on Ukraine and Belarus. Psychiatrists call it the “nocebo” effect: If you believe your health is in danger, you feel worse. Such feelings were compounded by the stress, disruption, and economic losses caused by moving, and by losing jobs, livelihood, and community.

After the collapse of the Soviet Union in 1991, responsibility for the affected areas ceased being centralized. Havenaar recalls how the different radiation levels for later evacuations set by the different countries added to the contradictions, confusion, and concern.

Even if the radiation exposure does not cause physical health problems, mental health matters. “It affects people’s daily lives. It’s linked to physical health, mortality, and the ability to work,” says Havenaar’s colleague Evelyn Bromet of Stony Brook University. “And if you don’t deal with things, they fester.” Awareness about mental health is growing, she says—in part, because of post-traumatic stress disorder and suicides among soldiers from recent wars and emergency personnel who responded to the 2001 World Trade Center attacks. “A lot of things have contributed. There is now a broader understanding of common disorders like depression,” she says.

Timothy Mousseau, a population biologist at the University of South Carolina, says that when he and his colleague Anders Møller of the Université Paris–Sud first began fieldwork in the Chernobyl exclusion zone more than a decade ago, they had heard that everything was fine and the animals were thriving. They started looking for signs of adaptation. “We thought maybe female birds would change how they allocated antioxidants to eggs,” says Mousseau. But they found no evidence of adaptation. In fact, he says, “we realized they live half as long as they normally would.”

In the ensuing years, Mousseau and Møller have studied birds , insects, rodents, and larger mammals around both Chernobyl and Fukushima. Living in a radioactive area, says Mousseau, “causes tumors, cataracts, reproductive problems, smaller brains.” In their studies, he says, he and Møller found no threshold below which there was no health effect. Moreover, he adds, animals living in the wild are more sensitive to effects of ionizing radiation than lab animals. He also points to the finding that cesium-137 is not migrating as deep into the soil as expected. The isotope gets stuck in the top 5–10 cm of soil, which prolongs its ecological impact.

It’s rare for wild birds to have tumors, but population biologists observe them in 2–3% of birds near Chernobyl, as with this great tit.

Since Fukushima, Mousseau says, “there has been a tremendous investment in Japan in radionuclide movement through the biosphere.” A spillover effect, with increased funding for research at Chernobyl, mostly focused on engineering and geochemistry, has also occurred, he adds.

So what should be done differently in the event of a future nuclear accident? In preparation, says Havenaar, “doctors in disaster areas should receive training packages, to remind them how radiation works, what it can cause, what it can’t, and about the psychological effects.”

Bromet wants to see risk conveyed more effectively. She points to radiation scientists, saying they need to communicate better with the public. Contradictory statements by scientists and government authorities breed fear and lack of trust, she says.

The public’s trust of government and nuclear industry representatives is low when it comes to information related to a disaster. “The authorities know radioactivity scares people, so they are cautious about what they say. And that can be perceived as them keeping the truth from the people,” says Beyea. One lesson learned from Chernobyl, he says, is that public trust matters. “The chance of a major nuclear accident is small. To efficiently allocate emergency-planning resources, you need an all-hazards approach, to be better prepared for everything—chemical releases, terrorists, …”

Bringing in experts and tools that are perceived as impartial is one approach to winning public trust. In the wake of Chernobyl, Germany installed a network of 1800 radiation monitors around the country; their readings are now accessible online. Following the Fukushima nuclear accident, members of the public were provided with Geiger counters to map radioactive hotspots. And researchers in Japan developed and distributed a photodiode radiation detector that plugs into the microphone port of a smartphone for data logging and display.

To reassure and protect the public, Japan is monitoring crops from the Fukushima region. And the Fukushima Ambassadors program brings international students for visits to learn about the area and the accident. The program reminds locals that they have not been forgotten and is intended to serve as an antidote to fears of being in the area.

International students visit Fukushima for two-week stints as part of a program to learn about the area and show locals they are not fearful of the radiation, and that their nuclear disaster has not been forgotten. Here, the students are preparing rice cakes.

Unsurprisingly, nuclear accidents elicit a backlash of antinuclear sentiment. That worries people who hold that nuclear power is a necessary part of the energy mix needed to combat climate change. Says Georg Steinhauser of Leibniz University’s IRS, “It’s important not to let accidents like Chernobyl and Fukushima prevent the development and implementation of safer reactors.”

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Engineering Ethics - Chernobyl’s Case Study

The Chernobyl disaster was nuclear accident that occurred at Chernobyl Nuclear Power Plant on April 26, 1986. A nuclear meltdown in one of the reactors caused a fire that sent a plume of radioactive fallout that eventually spread all over Europe.

Chernobyl nuclear reactor plant, built at the banks of Pripyat river of Ukraine , had four reactors, each capable of producing 1,000 MWs of electric power.

On the evening of April 25 th 1986 , a group of engineers, planned an electrical engineering experiment on the Number 4 Reactor. With their little knowledge on Nuclear physics, they thought of experimenting how long turbines would spin and supply power to the main circulating pumps following a loss of main electrical power supply.

Following is an image of the Chernobyl nuclear power plant.

What Led to the Disaster?

Let us now see what led to the disaster.

The reactor unit 4 was to be shut down for routine maintenance on 25 April 1986. But, 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 main 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 in the event of a loss of power .

Due to the misconception that this experiment belongs to the non-nuclear part of the power plant, it was carried out without a proper exchange of information between the testing department and the safety department. Hence the test started with inadequate safety precautions and the operating personnel were not alerted to the nuclear safety implications of the electrical test and its potential danger.

The Experiment

According to the test planned, the Emergency Core Cooling System (ECCS) of the reactor, which provides water for cooling the reactor core, was shut down deliberately.

For the test to be conducted, the reactor has to be stabilized at about 700-1000 MW prior to shut down, but it fell down to 5000 MW due to some operational phenomenon. Later, the operator working in the night shift committed an error, by inserting the reactor control rods so far. This caused the reactor to go into a near-shutdown state, dropping the power output to around 30 MW.

Since this low power was not sufficient to make the test and will make the reactor unstable, it was decided to restore the power by extracting the control rods, which made the power stabilize at 200 MW. This was actually a violation to safety law, due to the positive void co-efficiency of the reactor. Positive void coefficient is the increasing number of reactivity in a reactor that changes into steam. The test was decided to be carried out at this power level.

Actually, the reactors were highly unstable at the low power level, primarily owing to the control rod design and the positive void coefficient factors that accelerated nuclear chain reaction and the power output if the reactors lost cooling water.

The following image shows the reactor 4 where the experiment was conducted. This picture was taken after everything was restored.

At 1:23, on April 26 th 1986, the engineers continued with their experiment and shut down the turbine engine to see if its inertial spinning would power the reactor’s water pumps. In fact, it did not adequately power the water pumps and without the cooling water the power level in the reactor got surged.

The water pumps started pumping water at a slower rate and they together with the entry to the core of slightly warmer feed water, may have caused boiling (void formation) at the bottom of the core. This, along with xenon burn out, might have increased the power level at the core. The power level was then increased to 530 MW and continued to rise. The fuel elements were ruptured and lead to steam generation, which increased the positive void coefficient resulting in high power output.

The high power output alarmed the engineers who tried to insert all the 200 control rods, which is a conventional procedure done in order to control the core temperature. But these rods got blocked half the way, because of their graphite tip design. So, before the control rods with their five-meter absorbent material, could penetrate the core, 200 graphite tips simultaneously entered the core which facilitated the reaction to increase, causing an explosion that blew off the 1,000-ton heavy steel and concrete lid of the reactor, consequently jamming the control rods, which were halfway down the reactor. As the channel pipes begin to rupture, mass steam generation occurred as a result of depressurization of the reactor cooling circuit.

As a result, two explosions were reported. The first one was the initial steam explosion. Eventually, after two to three seconds, a second explosion took place, which could be possibly from the build-up of hydrogen due to zirconium-steam reactions.

All the materials such as Fuel, Moderator and Structural materials were ejected, starting a number of fires and the destroyed core was exposed to the atmosphere. In the explosion and ensuing fire, more than 50 tons of radioactive material were released into the atmosphere, where it was carried by air currents. This was 400 times to the amount of radioactive materials released at the time of Hiroshima bombing.

Fatal Effects of the Disaster

The Chernobyl Nuclear Power Plant disaster in Ukraine, is the only accident in the history of commercial nuclear power to cause fatalities from radiation.

There were many fatal effects due to the radiation released. A few of the effects are listed below −

Two workers had died. One immediately got burnt to ashes after the accident, while the other was declared dead at the hospital within few hours of admission.

28 emergency workers and staff died within 4 months of the accident due to the thermal burns and the radiation effect on their bodies.

This accident created 7,000 cases of thyroid cancer.

Acute radiation syndrome (ARS) was diagnosed in 237 people, who were on-site and involved in cleaning up

The land, air and ground water were all contaminated to a great extent.

The direct and indirect exposure to radiation led to many severe health problems such as Downs Syndrome, Chromosomal Aberrations, Mutations, Leukemia, Thyroid Cancer and Congenital Malfunctions, etc.

A number of plants and animal faced destruction as after-effect.

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Case Study on Chernobyl Nuclear Disaster

Chernobyl nuclear disaster case study:.

Chernobyl nuclear disaster is the catastrophe which occurred at the Chernobyl nuclear power plant on April 26, 1986. Chernobyl nuclear power plant is situated in Ukraine, a part of a former USSR and today the plant is associated with the enormous disaster, which caused many lives and damaged the natural environment seriously. The disaster had an explosive character and during the explosion the fourth reactor was destroyed entirely and millions of tons of radioactive elements got into the atmosphere. The disaster is considered to be the most serious one which has ever occurred at nuclear power plants according to the number of victims and the damage to the environment. After a few days of the explosion 31 people died and several years after more than 80 people died because of its effect.

Enormous resources were used to neutralize the consequences of the disaster and more than 500 thousand people took an active part in the solution of this problem.The disaster did not only influence Ukraine, but the neighbour countries, like Russia and Belorussia and the whole Eastern Europe. It is obvious that vast territories and many towns and villages around Chernobyl were evacuated and more than 100 thousand people had to look for new home.Chernobyl nuclear disaster influenced the position of the USSR on the political arena negatively, because the country spent milliards of dollars to solve the problem and hid the documents which could explain the reason of the disaster and its real consequences. Naturally, the region will suffer from the effect of the disaster for hundreds of years till the area can be called ecologically safe.Chernobyl nuclear disaster can surely be called one of the most harmful accidents in the human history and its effect will disturb people for centuries.

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If a student is asked to complete a Chernobyl nuclear disaster case study, he should spend much time to get to know about the problem from the most reliable literary sources. There are many encyclopaedias and articles in the Internet which can be useful to students who require data for the analysis. A student should try to find out the cause of the explosion and value its consequences soberly and finally present reasonable solutions to the problem.It is natural, that the process of case study writing causes a range of troubles and a student has to apply for the piece of advice in the Internet. With the professional assistance of a free example case study on Chernobyl nuclear disaster a student can learn how to compose a successful paper correctly. Experienced writers share their knowledge and skills with students, so it is sensible to read a free sample case study on Chernobyl nuclear disaster in the web and increase your chance to prepare a good paper yourself.

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Case Study: Chernobyl Disaster

2018, International journal of advanced research in computer science and software engineering

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