Chernobyl Disaster: 40 Years Later

On April 26, 1986, at 01:23 Moscow time, an explosion occurred at the Chernobyl Nuclear Power Plant named after V.I. Lenin, which forever changed the world. The fourth power unit of the station was completely destroyed, and an enormous amount of radioactive substances — about 38 million curies — was released into the atmosphere. This disaster became the largest technological accident in human history, affecting the lives of millions of people.

Causes of the Tragedy: What Went Wrong

On the night of April 26, tests of a turbine generator were being conducted on the fourth power unit. The experiment program was insufficiently worked out, and the personnel did not have a full understanding of the physical processes in the reactor. Due to gross violations of instructions and the unsuccessful design of emergency control systems, an uncontrolled increase in power occurred. Two explosions (steam and, presumably, hydrogen) destroyed the reactor unit and the building.

The main cause of the accident is attributed to a combination of human error and design flaws: the RBMK-1000 reactor had positive reactivity — under certain conditions (such as the introduction of a void coefficient), power did not decrease, but catastrophically increased. Despite preliminary signals from the emergency protection system, the personnel continued the experiment, leading to a thermal explosion. Errors in design and violations of operational rules became a fatal cocktail that destroyed the reactor.

Chronicle of the First Days: Silence, Smoke, and Panic

Immediately after the explosion, a fire began, which lasted for about 10 days. Firefighters were the first to enter the fray, even without special radiation suits. They extinguished burning graphite and structures, receiving lethal doses of radiation. 31 people died in the first months from acute radiation sickness, including firefighters Vladimir Pravik and Viktor Kibenko (posthumously Heroes of the Soviet Union).

In defiance of the danger, the active zone was extinguished from helicopters, dropping mixtures of boron, lead, and dolomite. However, the Soviet leadership remained silent in the first days: the first TASS message appeared only on April 28, and it was extremely brief. Residents of the nearby city of Prypiat were not told the truth — they were only evacuated on April 27, nearly 36 hours after the explosion.

The population of Prypiat was exposed to radiation that was tens times higher than the consequences of the Hiroshima bombing. People were told that they were leaving for three days, but many never returned home. In the first weeks, about 116,000 people were evacuated from the 30-kilometer exclusion zone, and subsequently, more than 350,000 affected people from three republics.

Liquidators and the Price of Saving

About 600,000 people from all over the Soviet Union participated in the work to liquidate the consequences of the accident. Soldiers, miners, engineers, and volunteers built the sarcophagus, collected radioactive scrap metal, and decontaminated the soil. Often, they worked without modern protective equipment, risking their lives. Heroes went into the “dead zone” on the roof of the third block to drop the graphite debris, exposed to colossal radiation (so-called “biorobots”).

In memory of their bravery, monuments have been installed in many cities, and on April 26, in Russia and other CIS countries, liquidators are honored. Today, about 101,000 participants in the liquidation live in Russia, many of whom still receive social support from the state. Thanks to their sacrifice, it was possible to prevent a more catastrophic disaster: to build the sarcophagus (Object “Shelter”) and stop the spread of radiation.

Environmental and Medical Consequences

The radioactive cloud covered not only Ukraine, Belarus, and Russia, but also the entire Europe: from Sweden to Italy. The Homel and Mogilev regions were particularly affected. The total area contaminated by cesium-137 and strontium-90 was about 155,000 square kilometers, where about 7 million people lived. In Russia, 19 regions were contaminated.

Estimates of the number of victims vary. According to the UN (2005), the confirmed number of deaths from radiation sickness and oncology among liquidators and the population is about 4,000. Environmental organizations (such as Greenpeace) call the figures up to 100,000 victims in the long term. To this day, there are disputes about the real scale of the impact of low doses of radiation on health. It is known, however, that thyroid cancer in children in contaminated regions has increased hundreds of times.

Evacuation and Prypiat: A Ghost Town

Prypiat, built for the workers of the station and their families, was considered a model Soviet city with a population of about 50,000 people. After the evacuation, it slowly deteriorated, covered in rust and forest. Four decades later, the Ferris wheel, abandoned dolls, and empty schools have become symbols of the technological disaster. Today, Prypiat is a tourist attraction (pre-war — a popular place for radiotourism), but due to the occupation in 2022 and drone strikes in 2025, the exclusion zone has again been under threat.

The Exclusion Zone Today and New Threats of War

In 2016, the New Safe Confinement was installed over the destroyed fourth block — a massive arch structure costing about 1.6 billion euros, designed for 100 years. It replaced the old sarcophagus built in 1986 in an emergency. However, on February 14, 2025, a Russian drone (according to the Ukrainian side) pierced the outer shell of the confinement, causing a fire and partial loss of integrity.

The occupation of the Chernobyl zone in February 2022 became another challenge: Russian soldiers dug trenches in the “Red Forest” (the most contaminated area), raising radioactive dust. After the withdrawal of the occupiers, the zone returned under Ukrainian control, but incidents at the borders and drone strikes highlight the vulnerability of the shelter. According to Greenpeace, the full repair of the confinement may take 3–4 years and cost hundreds of millions of euros.

Nature Taking Its Toll: The Paradox of Revival

In the absence of humans, the exclusion zone has turned into a unique ecosystem. Here, Przewalski's horses, bears, leopards, wolves, and white-tailed eagles live. Interestingly, the evolution of animals has taken an unusual path: some species (wolves, frogs) have developed mechanisms of protection against radiation, increased melanin production. Even fungi (Cladosporium sphaerospermum) have mutated, showing radiotropism — growth towards sources of ionizing radiation. “Nature takes its revenge when man leaves” — this expression could not describe the Chernobyl wilderness better, where silence has been replaced by the roar of wild life.