Ukraine unloaded the 'concrete coffin' that was about to collapse at the Chernobyl factory

Ukrainian authorities decided to remove the concrete dome surrounding the exploded reactor at Chernobyl to prevent it from collapsing after years of degradation.

SSE Chernobyl NPP, the Ukrainian company managing the Chernobyl nuclear power plant announced a review from experts showing that the concrete arches covering the No. 4 reactor are seriously degraded. On July 29, the company signed a $ 78 million contract with a contractor to remove the dome before 2023.

When the reactor core at the Chernobyl plant exploded in a periodic safety inspection on April 26, 1986, columns of radioactive material shot across four sides. The explosion and subsequent fires caused radioactive contamination to spread across Europe, but the area most heavily affected was the No. 4 reactor, where the accident occurred.

The scene of the new steel coffin covers the Chernobyl factory.(Photo: AFP).

Nearly two months after the disaster, about 600,000 Soviet workers were mobilized to build a giant concrete coffin covering the reactor to prevent leakage of radioactive materials such as corium, uranium and plutonium. The construction process caused many workers to be exposed to dangerous amounts of radiation, at least 31 people died from radiation poisoning.

Concrete arches are designed to be robust, using 400,000m3 of concrete and about 7,257 tons of steel but construction is rushed. As workers try to complete the construction as quickly as possible to avoid injury to their health, they do not seal the joints of the dome. They also missed many holes in the vaulted ceiling, allowing water to seep through, leading to erosion.

The entire dome should be removed before collapsing. The construction workers will reinforce the concrete coffin before dismantling each part with the help of the robot crane. Removed parts will be cleaned and removed for recycling or disposal. According to the contractor, removing all parts at the same time will increase the risk of collapse of the arch layer, releasing large amounts of radioactive material.

In the past 9 years, workers have built a new 32,000-ton steel casket covering the old concrete dome, ensuring radioactive material does not leak into the air. Parts are assembled in Italy, then transported to the construction site by 18 ships and 2,500 trucks. The project was pulled to the last place in 2016, becoming the largest land transport object and inaugurated in July this year. This steel coffin is expected to stand firm for 100 years, allowing workers enough time to clean up the area.

After dismantling the concrete coffin, workers will begin clearing radioactive waste that remains in the No. 4 reactor. The process includes smoking radioactive particles and cleaning pasty mixes formed when Soviet workers Pour sand, lead and baron into a burning reactor. This work will last until 2065.

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