Ukraine’s president has unveiled plans for a new nuclear waste repository at Chernobyl, which 35 years ago this week became the site of the worst nuclear accident in history, driving tens of thousands from their homes and leaving contamination that will linger for hundreds of years.

To mark the anniversary of the disaster, Volodymyr Zelensky visited the site with Rafael Mariano Grossi, director general of the International Atomic Energy Agency, and vowed to “transform the exclusion zone, as Chernobyl is referred to, into a revival zone.”

“Ukraine is not alone, it has wide support from its partners,” Zelenskyy said. “Today the new repository has been put into operation and it is very important that today a license to maintain the new repository will be obtained.”

Ukrainian authorities are undertaking to use the deserted area surrounding the stricken plant to build a facility that would store nuclear waste for at least 100 years, and the new repository is expected to open this year.

The country operates 15 nuclear reactors that it inherited from the Soviet Union. Like Chernobyl, these reactors, nearly all of which have reached their retirement age of 40 years, became Kiev’s responsibility when the country gained independence from Moscow in 1991.

The new waste site will be used to store the spent fuel and other radioactive waste these reactors produce, theoretically allowing Ukraine to cease shipping its nuclear castoffs to Russia for processing and storage. The government estimates that the new repository will save up $200 million dollars a year in fees paid to Moscow for spent fuel and waste handling.

Grossi tweeted that the IAEA “will continue working tirelessly in addressing decommissioning, radioactive waste and environmental remediation related with Chernobyl accident.”

Reactor No 4 at the Chernobyl, located 110 kilometers north of Kiev, exploded and caught fire deep in the night on April 26, 1986, shattering the building and releasing more than 400 times more radioactive material into the atmosphere than the Hiroshima bomb.

In the days that followed, the nuclear fuel continued to burn, issuing clouds of poisonous radiation and contaminating as much as three quarters of the European continent, hitting northern Ukraine, Russia and Belarus especially hard.

More than 600,000 liquidators – a loose term enveloping police, fire fighters, military, conscripts and other state safety employees – were rushed to the site with minimal protective gear and hardly any plan for extinguish the carcinogenic blaze.

No word came from the Kremlin as to what had happened. Afraid of losing face, Soviet authorities kept silent as the radiation crawled north. They did quietly evacuate 48,000 residents of the city of Pripyat ­– the workers’ town located 3 kilometers from the site of the explosion – but not until the afternoon of April 27, a whole day later. By early May, Swedish nuclear authorities noticed mysterious spikes in their own radiation monitors and sounded the alarm.

A memorial at the entrance to the Chernobyl nuclear power plant. Photo: - Credit: Nils Bøhmer/Bellona

Finally, on May 14, Communist Party Secretary General Mikhail Gorbachev, went on television and admitted to the disaster. Authorities responded by relocating 116,000 people from the 30-kilometer exclusion zone surrounding the destroyed reactor.

In following years, the number of evacuees swelled to 230,000. All the same, 5 million Belarusians, Ukrainians and Russia’s still live in areas tainted by persistently high radiation levels.

The liquidators fought to build a containment structure of cement and steel over the reactor to squelch radiation emissions. The ad-hoc construct trapped 200 tons of uranium, but many liquidators feared at the time that the cement barrier would eventually give way. In 2005 it did.

In November, 30 years and six months after the explosion, the New Safe Confinement, a €1.5 billion, 36,000 ton steel structure, was moved laboriously into place over the wreckage of the number 4 reactor.

A view of the New Safe Confinement structure. Photo: - Credit: Nils Bøhmer/Bellona

Financed by donations from more than 40 countries coordinated by the European Bank of Reconstruction and Development, the New Safe Confinement is the largest movable land-based structure on earth, with room inside for Paris’s Notre Dame cathedral.

But even so, the molten radioactive debris within the enormous dome, which is being dismantled by robots, eventually must be stored somewhere, and funding questions surrounding that issue persist.

What impact the radiation had, and how many early deaths it brought about, remains disputed. A UN report from 2005 suggested 4,000 long-term cancer deaths would result among those who received the highest radiation doses.

In the following year, Belarus, probably hardest hit by the radioactive fallout, challenged that, and produced data saying the country alone would see 93,000 cancer deaths stemming from the disaster. Other reports forecast 60,000 deaths in Russia, and a combined death toll in Belarus and Ukraine reaching 140,000.

A clear list of obituaries may never emerge. The massive resettlement means that many who left when Pripyat and surrounding country was evacuated may have already died.

Even with new shelter is in place, the surrounding exclusion zone of around 2,600 square kilometers will remain uninhabitable – and it will take another 20,000 years before people can live near the plant again.

The Ukrainian authorities are calling for the exclusion zone to be included in the UNESCO World Heritage List, since the object is a unique place “of interest to all mankind.” The Ministry of Culture of Ukraine has already taken steps to recognize the zone as a monument, which will attract more funding and tourists.

“Chernobyl should not become a wild playground for adventure hunters,” Ukrainian Culture Minister Oleksandr Tkachenko told the Associated Press. “People should leave the exclusion zone with the awareness of the historical memory of this place and its importance for all mankind.”