Tim Porter/Wikimedia Commons

After the disaster at Chernobyl’s number four nuclear power reactor, a “sarcophagus” was built around the site to contain the deadly radiation emanating from the ruins. The old Chernobyl Nuclear Power Plant sarcophagus, also known as the Shelter Structure, has been in place for many years, and those years have taken a toll on the building. A new structure was deemed necessary to keep the radiation contained, and so the New Safe Confinement building was built over the ruins of the Shelter Structure, a new sarcophagus encapsulating the old, broken one.

The Chernobyl disaster

On April 26 of 1986, the number four reactor at the Chernobyl Nuclear Power Plant went into meltdown, resulting in possibly the worst nuclear disaster in all of history. This disaster was rated a seven on the International Nuclear Event Scale, the most severe rating possible. Only one other disaster was even close to the horror of the Chernobyl event, the 2011 Fukushima Daiichi nuclear disaster in Japan.

The Chernobyl disaster is believed to have started during a safety test on one of the nuclear reactors. The test was meant to explore what would happen if there was an electrical power outage that resulted in a loss of cooling for the reactor. Other tests had already been safely done on this issue, with no usable results. However, on the occasion of this test, the time had to be pushed back by an unexpected 10 hours, resulting in it having to be conducted by an unprepared shift of workers.

Unpreparedness for the test led to a failure to follow proper safety procedures which resulted in unstable conditions that exploited flaws in the design of the reactor and lead to an uncontrolled nuclear chain reaction. The massive amount of energy released by the chain reaction vaporized the water in the coolant systems, demolishing part of the reactor in a devastating steam explosion. That damage allowed an open-air reactor core fire to start and released radioactive contaminants into the surrounding area.

The old sarcophagus

Radiation from the Chernobyl nuclear reactor forced the creation of a 10-, then a 30-mile exclusion zone around the power plant. Nearly 50,000 people were forced to leave their homes in the nearby town of Pripyat, then another 68,000 were later moved from the larger exclusion zone. In order to contain the radiation as much as possible, the government quickly began construction on the Chernobyl Nuclear Power Plant sarcophagus.

Construction on the sarcophagus began on May 20th, 1986, just 24 days after the disaster. In less than a year, the sarcophagus was finished, although not without serious issues. The building became so radioactive during its construction that at the end, no human being could screw down nuts onto bolts or weld together the seams of metal sheets. Robots were used to complete some of the work, but parts of the building were never finished, hastening the sarcophagus’ deterioration.

By the end of 1988, scientists in the Soviet Union had declared that the Chernobyl Nuclear Power Plant sarcophagus would last, at most, another 30 years. In 1996, it was determined that the building had deteriorated to the point that no further repairs were possible and a new sarcophagus would be needed as soon as possible.

New Safe Confinement

The New Safe Confinement megaproject began construction in September of 2010. However, the project had been started several years earlier, with a competition for the design of the structure being held and funding being secured for the massive undertaking. Eventually, French consortium Novarka won the bid to design and build the new sarcophagus.

Since tearing down the old sarcophagus would allow the release of a massive amount of radioactive contaminants, the new structure is being built around the old one, completely encapsulating it and, in turn, the reactor inside of the old sarcophagus (kind of like extremely deadly Russian nesting dolls.) In order to surround the old structure, the New Safe Confinement building was built as a massive arch having an overall span of over 500 feet.

In order to ensure that the new sarcophagus did all it was hoped to, it was created with specific design goals. First, it had to make the area around the radioactive ruins of the number four reactor safe by containing the radiation. Second, it needed to reduce the speed of deterioration of the old sarcophagus and the reactor four ruin itself. Third, the new sarcophagus needed to be able to mitigate the fallout of the old shelter’s potential collapse. Finally, there had to be enough room in the new structure to allow for the safe demolition of the old sarcophagus. The New Safe Confinement building also needed to qualify as a nuclear entombment device, a structure which would last long enough to allow the radioactive materials inside to break down to safe levels.

The new sarcophagus was declared complete on July 3rd of this year. On July 10th, the keys for the structure (as well as the responsibility for its maintenance) was turned over to Ukrainian government.

Radioactive tourism

Largely in part to the popularity of the S.T.A.L.K.E.R. video game franchise, tourists have been drawn to the radioactive ruins of Chernobyl for a little over a decade. Then, the second wave of tourists has descended upon the disaster area, eager to see the massive construction that is the New Safe Confinement building. Now, with the airing of the “Chernobyl” miniseries on HBO, more people came to see Chernobyl for themselves.

The Ukrainian government has decided to capitalize upon people’s fascination with the terrible disaster, designating Chernobyl an official tourism site. While wildlife has returned to areas inside of the exclusion zone, tourists are warned that many radioactive elements are still present in the dust coating the ruins and in some places the radiation is still at dangerous levels.