The Chernobyl nuclear disaster occurred on April 26, 1986 at the Chernobyl Nuclear Power Plant in Ukraine. During a planned maintenance shutdown, a power surge caused two explosions that destroyed the reactor and released radiation into the atmosphere. Over 300,000 people were evacuated and large areas of Ukraine, Belarus, and Russia became contaminated. While dozens died in the immediate aftermath, it is estimated that thousands more developed cancer years later due to radiation exposure. The disaster created a large exclusion zone and the reactor is now contained under a massive new sarcophagus, where it will remain radioactive for centuries.

1. Chernobyl
Nuclear Disaster Where and When?
April 26,1986 – Chernobyl
Nuclear Power Plant,Ukraine
Former Soviet Union
81 miles North of Kiev
12 miles South of Belarusian border

2. What Went Wrong?
Shutdown preparation for planned
maintenance of reactor number four
Operators , in violation of norms, disabled the
auto-shutdown mechanisms on April 25 -
UNSCEAR report
At 1.23 on April 26, when extremely hot nuclear fuel rods were lowered
into cooling water, an immense amount of steam was created, which —
because of the reactors’ design flaws — created more reactivity in the
nuclear core of reactor number 4. A resultant power surge caused an
immense explosion that detached the 1,000-ton plate covering the reactor
core, releasing radiation into the atmosphere and cutting off the flow of
coolant into the reactor.

3. THE BLAST
later, a second explosion of even greater power than the first
blew the reactor building apart and spewed burning graphite
and other parts of the reactor core around the plant, starting a
number of intense fires around the damaged reactor and reactor
number 3, which was still operating at the time of the explosions.
The explosion and fire spewed an equivalent of at least 20 Hiroshima
bombs’ worth of radiation, mostly within about 25 miles of the reactor
building

4. Two significant types of radionuclides were
released into the atmosphere
• Iodine-131
8 Day Half Life
• Caesium-137
30 Year Half Life

5. SCALE
Large Quantities of Radioactive Substances Were Released For 10 Days Constantly
•The radioactive cloud dispersed around
entire Northern Hemisphere
• Deposited large quantities of radioactive substances over
parts of former Soviet Union, most notably Ukraine, Belarus and
Russian Federation
• Contaminated Land, Water and Biota
• Caused large-scale social and Economic Disruptions

6. Human Impact of Chernobyl
• Two workers died in the immediate aftermath
• Out of 134 plant staff and rescue workers,
exposed to large-scale radiation, 47 died in
coming months. Several hundred thousand
involved in recovery ops were
exposed to radiation.

7. • Svetlana Alexievich
• Belarusian journalist/ Nobel Laureate
• Voices from Chernobyl

8. At the time of disaster, experts predicted 40 thousand extra cancer
deaths due to radiation spewed across erstwhile Soviet Union
• It is hard to confirm the actual number
• However cases of Thyroid cancer in children skyrocketed
• 7000 cases were recorded in Ukraine, Belarus & Russia
by 2005
Nila Bandarenko from Zhytomir has her third operation on her thyroid gland. After her second
operation microscopic particles of the cancer got into her blood vessels and the cancer started
growing there. Bandarenko also has kidney cancer – Greenpeace; 2006

9. Environmental Ramifications
Radiation released by the was carried directly over
what is now called the Red Forest. Radioactive
particles settled on trees, killing approximately 400
hectares of pine forest. The Red Forest is now one of
the most contaminated terrestrial habitats on earth.

10. The Red Forest
• Formerly known as Wormwood Forest (10 sq. KM)
• Now within the nuclear exclusion zone of Chernobyl

11. Water Contamination
• Parts of Red Forest were bulldozed and
buried causing the radiation to seep into
groundwater
• Consequently, other water sources were also
contaminated

12. Effects on Flora
• Initial damage to the “Red Forest”
• Stunted growth has been observed in the pine trees

13. Few wild animals lived in the region in 1986 because their habitats had been
destroyed for Soviet dairy farms and pine plantations. But, surprisingly, large
mammals started appearing almost immediately after the evacuations, and
animal populations soon saw a rise (Mycio; 2013)
“world’s biggest radioactive wasteland could become Europe’s largest wildlife sanctuary”
-Mary Mycio

14. Elks Eagles
Deer Wild Boars

15. • Reactor No. 4 is now secured under a giant steel-concrete sarcophagus
• It is expected to remain radioactive for 1000 years

16. • The remaining three reactors continued to operate even after the fallout
• In 1991, reactor No. 1 suffered a major fire and was subsequently shut-down
• In November 1996, Reactor No. 1 was shut down, followed by Reactor No. 3 in 2000

17. • More than 300,000 people were evacuated
• 50,000 from the surrounding town of Pripyat