By Burc Eruygur
ISTANBUL (AA) - Thirty-seven years have passed since the fourth reactor at the site of the Chernobyl nuclear power plant in Ukraine's Kyiv region exploded, resulting in an accident widely regarded as the world's worst nuclear disaster.
The accident, which took place on April 26, 1986, occurred after a sudden surge of power during a reactor systems test at the fourth unit of the nuclear power station at Chernobyl, which is located close to 110 kilometers (68.3 miles) from Kyiv, the capital of the then-Ukrainian Soviet Socialist Republic.
The plant was also only 3 kilometers (1.8 miles) from the city of Pripyat, which was built to house workers at the plant in the 1970s.
The explosion at the fourth reactor blew off the roof of the plant and exposed the core, resulting in the spread of radioactive material over the surrounding territory, which prompted the Soviet Union to create an exclusion zone with a radius of 30 kilometers (18.6 miles).
In the immediate aftermath of the accident, more than 30 firefighters were killed and millions more people were affected.
Roughly 8.4 million people in the former Soviet republics of Belarus, Russia, and Ukraine suffered the largest exposure to radiation, according to the official numbers, while an area of approximately 155,000 square kilometers (60,000 square miles) in these three countries was contaminated.
The borders of the exclusion zone have since been altered following the dissolution of the Soviet Union, with Ukraine's State Emergency Services administering the Chernobyl Exclusion Zone, while the Polesie State Radioecological Reserve in neighboring Belarus also serves to enclose areas in the country affected by accident.
Meanwhile, later research into the accident showed that the radioactive clouds reached as far as the US, Canada, and even Japan.
Data from the World Health Organization indicate that 600,000 people who lived, worked, and took part in the disposal and cleaning operations in the initial exclusion zone of the disaster were exposed to high doses of radiation.
Around 5 million people in Belarus, Ukraine, and Russia continue to live in areas containing the risk of radiation.
- Erasing traces of Chernobyl disaster
Since the accident, the Chernobyl nuclear power plant has entered a stage of decommissioning, with the last of the three reactors still operational at the site having been shut down on Dec. 15, 2000.
The building housing the fourth reactor at Chernobyl has also been completely covered with a special steel tent since the accident, which was most recently reinforced by a new structure in 2016 named the New Safe Confinement.
In 2009, the Ukrainian government adopted a law on fully decommissioning the plant in four separate stages, with the goal of establishing an "environmentally safe system" in the area against radiation.
Under the law, in the first stage, which lasted until 2013, nuclear fuel was transported from power plants to warehouses.
In the second stage, which took place between 2013 and 2022, the reactors were put under protection and the reactor where the accident took place was isolated.
In the third phase, which began in 2022 and is scheduled to last roughly until 2045, experts will observe the reduction of radiation in the area after the Chernobyl site's isolation.
Lastly, the fourth and final stage of decommissioning involves dismantling the reactors and clearing the site of the Chernobyl nuclear power plant, which is expected to be finished by 2065.
- Russia-Ukraine war
Ukrainian President Volodymyr Zelenskyy, on the day of the start of the Russia-Ukraine war on Feb. 24, 2022, said in a statement on Twitter that Russian forces were trying to seize the Chernobyl nuclear power plant.
On the same day, Mykhailo Podolyak, a Ukrainian presidential adviser, announced that Ukraine lost control of the power plant after fierce clashes with Russian forces in the area.
A day later, Ukraine claimed that an increase in radiation level at the Chernobyl site was recorded but that the reason behind the increase could not be investigated due to clashes in the region. Russian officials denied the claims.
The International Atomic Energy Agency (IAEA) expressed "grave concern" over the situation at the Chernobyl Nuclear Power Plant, appealing to both sides for "maximum restraint to avoid any action that may put the country's nuclear facilities at risk."
On March 9, Ukrainian Foreign Minister Dmytro Kuleba called on the international community to "urgently demand Russia to cease fire" after the "only electrical grid" supplying the Chernobyl plant "and all its nuclear facilities" was damaged.
Two days later, energy to the plant, which had been maintained by backup generators with a 48-hour capacity, was restored via Belarus.
On April 1, Ukraine's nuclear energy provider Energoatom announced that Russian forces withdrew from the Chernobyl site.
Meanwhile, about 14,000 hectares of land in the Chernobyl Exclusion Zone burned during Russia's control of the site, according to the European Forest Fire Information System last September.