Chernobyl Disaster

Chernobyl Disaster: On the morning of April 26, 1986, something catastrophic happened at the Chernobyl Nuclear Power Plant in Pripyat, Ukraine. The reactor in Unit 4 exploded, and a huge amount of radiation was released into the area. At that time, Ukraine was part of the Soviet Union, and the aftermath of this event had significant and lasting impacts on the entire country.

What was the Chernobyl Disaster?

The Chernobyl accident in 1986 was the result of a flawed reactor design that was operated with inadequately trained personnel.
The resulting steam explosion and fires released at least 5% of the radioactive reactor core into the environment, with the deposition of radioactive materials in many parts of Europe.
The disaster was a unique event and the only accident in the history of commercial nuclear power where radiation-related fatalities occurred.
Two Chernobyl plant workers died due to the explosion on the night of the accident, and a further 28 people died within a few weeks as a result of acute radiation syndrome.
Some 350,000 people were evacuated as a result of the accident, but resettlement of areas from which people were relocated is ongoing.

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.

Impact of the Chernobyl Disaster

A major accident occurred, leading to the largest release of radioactive materials into the environment ever recorded. For 10 days, a significant amount of radioactive dust was released into the air, causing potential harm to the populations of Belarus, Ukraine, and Russia, with social and economic consequences. The incident released various radioactive substances, including xenon gas, iodine, and cesium, affecting different areas.
The town of Pripyat was completely evacuated on April 27th, relocating around 45,000 residents to safer places. By May 14th, about 116,000 people within a 30-kilometer radius had been evacuated. Some individuals returned to live within the contaminated zone unofficially, experiencing adverse health effects.
After the disaster, over 220,000 people were resettled in areas with little to no contamination. The initial exclusion zone of 30 kilometers was expanded to cover 4300 square kilometers to safeguard against the widespread radiation in the region.