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CHERNOBYL
April 26, 1986
What is Chernobyl?
• Site of the worst nuclear reactor disaster in history.
• The station consisted of four reactors that together produced about 10% of Ukraine's electricity at the time of the accident.
When and Where did this take place?
• April 26, 1986
• In north central Ukraine near the city of Pripyat.
What happened there?
• On Saturday April 26, 1986 at 1:23 a.m. reactor 4 suffered a catastrophic steam explosion resulting in a nuclear meltdown, a series of additional explosions and a fire.
• The radiation was not contained and radioactive particles were carried by wind across international borders.
What is a nuclear meltdown?
• A nuclear meltdown occurs when the core of a nuclear reactor stops being properly controlled and cooled.
• This is caused by a failure of control or safety systems, and fuel assemblies inside the reactor begin to overheat and melt.
How does Chernobyl’s effect measure up to the atomic bombs dropped on Hiroshima and
Nagasaki?
• The accident at Chernobyl was approximately 400 times more powerful than the atomic bomb dropped on Hiroshima.
What countries were affected by this disaster?
• Ukraine• Belarus• Poland• Sweden • Southwest Russia• The plume also drifted over parts of
Western Europe and eastern North America.
• Large areas in Ukraine, Belarus, and Russia were badly contaminated, resulting in the evacuation and resettlement of over 336,000 people.
• About 60% of the radioactive fallout landed in Belarus.
How did this affect people?
• 237 people suffered from acute radiation sickness• "tasting like metal“• sensation similar to that
of pins and needles all over the face
• 31 died within the first
three months • Most were fire and rescue
workers trying to bring the accident under control – they didn’t know how dangerous the radiation exposure was.
• 135,000 people were evacuated from the area• 50,000 were from Pripyat• Left their belongings
behind because they were told they’d be gone a few days.
What are the environmental consequences?
• The lighter parts of the fallout and radiation were carried into the atmosphere. • Fallout is radioactive “dust” that falls from
the sky
• Spread into and polluted groundwater and surface water. • Environmental impact will be long term and
impact many things.
How did this affect plants and animals?
• Mutations did occur in plants and animals after the plant explosion.
• After the disaster, 2.5 square miles of pine forest close to the reactor turned ginger brown and died, earning the name of the “Red Forest”.
• Some animals in the worst-hit areas also died or stopped reproducing. Animals were also born with physical deformities.
• Despite the increased radiation levels, rare species are now returning in large numbers to the area.
How was this area cleaned up after the
accident?
• Emergency workers (liquidators) were drafted into the area and helped to clean up the plant premises and the surrounding area.
• These workers were mostly plant employees, fire-fighters, soldiers and miners from Russia, Belarus, Ukraine and other parts of the former Soviet Union.
• The exact number of liquidators is unknown because there are no completely accurate records of the people involved in the clean-up.
• The duties of the liquidators varied. • Decontamination
• Establishment of settlements and towns for plant workers and evacuees
• Built waste repositories, dams and water filtration systems
• The “sarcophagus”, which entombs the entire fourth reactor to contain the remaining radioactive material.
• The Ukrainian government continued to let the three remaining reactors operate because of an energy shortage in the country.
• Power plant was completely shut down in 2000.
Future Repairs . . .
• The sarcophagus is not an effective permanent enclosure for the destroyed reactor. • If it collapses another cloud of radioactive dust
could be released. • The sarcophagus is in such poor condition that a
small earthquake or severe wind could cause the roof to collapse.
• Water continues to leak into the shelter, spreading radioactive materials throughout the wrecked reactor building and potentially into the surrounding groundwater.
• In September 2007, Ukraine approved the building of a steel casing over the reactor. The casing will cost $1.4 billion.
Can you visit there today?
• Although the Chernobyl Exclusion Zone (30 miles surrounding the site) and certain limited areas will remain off limits.
• The majority of affected
areas are now considered safe for settlement and economic activity.
Children walk through a display in the Ukrainian capital's Chernobyl museum. Hanging from the walls are signs of villages that no longer exist, all the residents were evacuated.
