The largest nuclear accident in history initially unfolded in near silence. Explosions and a series of fires sent radioactive materials from the Chernobyl nuclear power plant into the atmosphere of Ukraine — but government officials of the Soviet Union remained largely quiet.
More than 30 years later, the causes and consequences of Chernobyl are well-known. Those mistakes, alongside the stories of victims, serve as an international blueprint for preventing nuclear disasters. Although circumstances unique to the former Soviet Union caused the accident, the literal and figurative fallout prompted the world to collectively enhance nuclear safety and strive to never repeat the errors and obstinacy that killed 30 people and put the lives of thousands at risk from radiation exposure.
Flaws and Failures
As the recent HBO historical drama series “Chernobyl” and countless books, documentaries and scientific articles have illustrated, the disaster could have been mitigated, if not prevented. Lack of training, systematic mismanagement, operator error and structural flaws triggered the disaster, while government inaction exacerbated the tragedy by delaying the evacuation of nearby residents. Leading into the evening of April 26, 1986, the residents of Pripyat, Ukraine, and most of the employees of Chernobyl had no idea that the potent mix of human misjudgment and mechanical defects would put them in harm’s way.
Of the many source materials that detail the disaster, a recap by the World Nuclear Association clearly describes what happened. In short, a defective reactor design, coupled with inadequately trained personnel, decimated the power plant’s fourth reactor. What was a training exercise to test the reactor during a power outage instead led to a power surge and the explosions, exposing the nuclear core and sending radioactive materials into the atmosphere. The nearby city of Pripyat wasn’t evacuated until nearly two days later and the Soviet government didn’t publicly acknowledge the disaster until April 28.
Acknowledgment and Change
Chernobyl revealed several gaps in nuclear safety, not just at the power plant but worldwide.
First, the disaster uncovered how Russia’s nuclear power plants were unlike any others in the world. According to the Nuclear Energy Institute, the power station used a type of reactor, RBMK, that wasn’t built anywhere else because of its inherent instability, particularly on start up and shutdown. Chernobyl operators conducted their power test unaware that RBMK reactors sometimes increased power. As the fourth reactor overheated, the power soared, accelerating the heating of the steam that drives power generation and also breaking fuel-packed pressure tubes. Also, whereas nuclear reactors in the U.S. rely on water as a cooling mechanism to keep steam generation in check, an RBMK reactor relied on graphite and water. At Chernobyl, graphite and fuel mixed, starting the fires and causing the release of radioactivity, according to World Nuclear Association.
After Chernobyl, it became apparent that the world lacked shared norms on nuclear safety. Countries and governments acted on their own. The accident showed a “need for a collective international focus on [nuclear] safety,” according to an International Atomic Energy Agency (IAEA) report on post-Chernobyl international law.
The world responded, a reaction that included a new emphasis on safety by the countries of the former Soviet Union in preventing nuclear disasters. As the World Nuclear Association outlines, nuclear engineers from those Soviet countries have learned from on-site visits to nuclear power plants in the Western world. Also, the World Association of Nuclear Operators formed in 1989, connecting nuclear power plant operators in more than 30 countries, while the IAEA reviews safety at still-operative Soviet reactors. Because of this openness and cooperation, the remaining RBMK reactors no longer have the deficiencies that doomed Chernobyl. And it’s largely assumed the governments of those former Soviet countries will act in a more transparent and urgent manner should there ever be an accident.
But thanks to a stronger emphasis on safety, a repeat of the Chernobyl tragedy is all but impossible, a German nuclear safety agency declared in 1996.
New Life and Tourists
Three decades later, the post-Chernobyl public health catastrophe that many experts had predicted hasn’t — at least not yet — materialized. Two plant workers died on the night of the explosion and an additional 28 employees and firefighters died weeks later from acute radiation poisoning. Since then, the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) said that while no one at a close distance from the Chernobyl plant suffered acute radiation, thyroid cancers found in patients were probably the cause of radioactive fallout. Aside from that finding, “the great majority of the population is not likely to experience serious health consequences as a result of radiation from the Chernobyl accident,” UNSCEAR said.
Meanwhile, the Chernobyl power plant is now enclosed in concrete, and the 2,000-mile radius around the site of the largest nuclear disaster is largely devoid of people. More than 300,000 residents had to leave the area. Yet in Belarus, thousands of people have returned to their homes in areas that were contaminated, with experts saying it was safe for them to eat foods grown there.
In the area closest to the power plant, known as the Exclusion Zone, wildlife appears to be diseased and there are lower rates of beneficial bacteria, according to National Geographic. Still, because of the lack of a human footprint, some species have expanded. And in a sign that all is not lost in Chernobyl, some areas are safe enough to allow “nuclear tourists.”
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