Published on 26 April 2026
Ukraine is marking 40 years since the explosion at the Chernobyl nuclear power plant, the world’s worst civilian nuclear disaster, with survivors of a cleanup operation returning to the site amid renewed debate over the human and environmental toll.
At 01:23 on April 26, 1986, a botched safety test at the Chernobyl plant in northern Ukraine, then part of the Soviet Union, resulted in a catastrophic explosion in reactor four.
The explosion tore the building apart and a huge plume of radioactive smoke spread into the atmosphere.
The nuclear fuel continued to burn for more than 10 days as helicopters dropped thousands of tons of sand, soil and lead to extinguish the fire.
The International Atomic Energy Agency (IAEA) later blamed “serious deficiencies in the design of the reactor and shutdown systems” as well as violations of operating procedures.
The radiation badly polluted large areas of Ukraine, Belarus and Russia before spreading throughout Europe.
About 600,000 “liquidators” – soldiers, firefighters, engineers, miners and physicians – were mobilized from across the Soviet Union over the next four years to control and clean up the disaster.
Their tasks ranged from flying over exposed cores to wash and seal them, sweeping radioactive dust from buildings and roads, burying toxic machinery, clearing forests, and even hunting animals to slow the spread of pollution.
Many people had little understanding of the dangers they faced. Ahead of the anniversary, a group of liquidators from Ukraine’s Poltava region returned to Chernobyl – or Chornobyl in Ukrainian – for a day trip to the site where they once worked in hastily issued uniforms and improvised protective gear.
He spoke about the duty he performed without hesitation, the losses he suffered, and the devastation that still haunts Ukraine.
The nearby city of Pripyat, once home to 48,000 people, remains a decaying ghost town inside an exclusion zone stretching thousands of square kilometers across northern Ukraine and neighboring Belarus.
Once open to tourists, the area has been closed since Russia’s invasion in 2022, leaving nature to reclaim the landscape and rare species like the endangered Przewalski’s horses to roam among the ruins.
