Taking Bearings

Chernobyl Nuclear Power Plant, Ukraine — Construction continues on New Safe Confinement (NSC) Dome

Chernobyl Nuclear Power Plant, Ukraine — Construction continues on the New Safe Confinement (NSC) dome intended to cover the sarcophagus entombing the remains of the No. 4 reactor at the Chernobyl Nuclear Power Plant destroyed by explosion in 1986.

Following the April 1986 accident, then Soviet Union threw “liquidators” (soldiers, miners, and impressed workers) into hastily construction of the original sarcophagus. Built with great loss of life due to radiation exposure and subsequent illness, Soviet engineers soon calculated the original containment building would last only about 30 years and would require constant maintenance to mitigate leaks.

Photo: The New Safe Confinement (NSC) Dome under construction over over the damaged reactor #4 and the original Soviet-built sarcophagus, with other reactors operational at the time of the accident in April 1986 in the foreground. Chernobyl Nuclear Power plant. Ukraine. May 2014. ©LMG Photo by K. Lee Lerner. All Rights Reserved.

Based on post-explosion surveys of the reactor debris, scientists estimate that 95% of the original radioactive core remains buried under tons of sand and hastily poured concrete,

The damaged core will be deadly hot for 3000 years.

Designed to last 100 years, the NSC will continue to contain the remaining radioactively hot reactor core elements and protect the slowly decaying pile of radioactively lethal debris. The NSC dome is the largest moveable land-based structure ever constructed. The dome is just over 531 feet long (162 m), 354 feet high (108 m), and spans 843 feet (257 m). The shield weighs nearly 80 million pounds (36,000 tonnes).

Built by the French consortium Novarka (a partnership of Vinci Construction Grands Projets and Bouygues Travaux), at a cost of more than $2B, the NSC is set to be moved over the existing sarcophagus by the end of 2017. After testing, the building will be hermetically sealed, with monitoring and maintenance controlled from a new operations building linked to the complex

Current plans call for an eventual dismantling of the original sarcophagus, which is partially supported by the structurally unsound reactor building damaged during the explosion. The NSC will also eventually house spent nuclear fuel from Reactors No.1, No. 2, and No. 3. Reactors No. 5 and No. 6 were never brought online.

[UPDATE: The NSC dome was moved over the original sarcophagus in November, 2016]