The situation at the site – no foreseeable solution and a race
against time
The reactor accident
On 26 April 1986, the worst nuclear disaster the world has yet seen occurred in reactor block number 4 at the Chernobyl nuclear power plant. The accident happened in a Russian-designed RBMK, a water-cooled pressure reactor moderated with graphite. Operating errors combined with a flawed technical design and an inadequate safety culture led to the disaster. Two explosions destroyed the reactor, and the graphite block caught fire and burned for ten whole days. Radioactive material was released into the atmosphere over a vast area. Within six months, a lid was constructed under difficult conditions to cover the remains in an attempt to contain the radioactive releases. This protective sarcophagus was expected to last for 20 to 30 years.
In addition to the destroyed reactor at the site, there remained reactor blocks 1 to 3. It was not until the end of 2000, when reactor 3 was shut down, that the entire Chernobyl nuclear power plant was taken off the grid. In February 2014, the Ukrainian regulatory authorities approved the decommissioning of blocks 1 to 3. The three reactor blocks are deemed to be ‘safely contained’.
The Shelter Implementation Plan (SIP)
In the ten years after the accident, no comprehensive solution was found that was economically and technically acceptable for dealing with the damaged reactor in the long-term. For this reason it was agreed to proceed in several stages. In 1997, the Shelter Implementation Plan (SIP) became the basis for international collaboration on how to begin to manage the site. Its objective in the medium-term is to better contain the highly radioactive remains – in order to buy some time to develop a long-term solution. An essential part of implementing the medium-term objective is the construction of a new containment structure for the damaged reactor. A new curved, protective shell made of steel, the New Safe Confinement (NSC), is to be placed over the reactor. Novarka, a French consortium, was awarded the contract to construct the new protective shell.ii
Due to the high level of radiation, the new containment cannot be constructed directly above the
deteriorated sarcophagus. . The new safety shell – a massive, self-supporting, domed, hall-like structure
257 metres wide, 165 metres long, and 110 metres high – is being manufactured in two parts to the side of
the damaged reactor. These two parts are supposed to be pushed together and joined, then slid over the
damaged reactor. iii When it is completed, it will be the largest movable structure on earth.
Implementing the SIP is proving to be much more difficult than expected. At the outset (1997), the
projected timeframe for the NSC was eight to nine years, meaning completion by 2005/2006. iv
Yet work on the gigantic structure did not even begin until April 2012. At the time, the completion date
for the NSC was then planned for October 2015. But construction of the new sarcophagus for what
remains of the Chernobyl nuclear power plant is taking longer than anticipated. It is now expected that the
completion date will be November 2017.v
Despite the unrest in eastern Ukraine, construction of the new protective shell went ahead.vi In 2014, both halves were put together up to their maximum height and placed together on the assembly platform. vii Both halves of the NSC are at present being joined together. viii
Beginning in 2015, the structure is supposed to be sealed by means of a double-walled outer shell and equipped on the inside with a crane facility. ix The most difficult part will then begin: the whole structure, some 31,000 tonnes in weight, is to be pushed into place over the damaged reactor using hydraulic lifting equipment, in a process lasting three days.
The costs of the SIP have also risen considerably, and its financing is being continually called into question. The European Bank for Reconstruction and Development (EBRD) took charge of administrating the SIP. In 1997, it set up the Chernobyl Shelter Fund (CSF).
According to a new investigation held in 2014, the total costs for the SIP have now been put at EUR 2.15 billion (USD 3.09 billion). In 2012, the costs were calculated at EUR 1.54 billion (about USD 2.1 billion). x The costs for the SIP have already more than quadrupled the original estimates of USD 768 million.. xi
Due to delays and the enormously increased costs, there is now a huge financing shortfall of EUR 615 million. In the meantime, the EBRD has agreed to provide EUR 350 million, with the expectation that there will be EUR165 million forthcoming from the G7/EU. At a donor conference being held on 29 April 2015, led by Jochen Flasbarth, a state secretary in Germany’s environment ministry (in the context of Germany’s presidency of the G7), this amount is to be the subject of negotiation.xii The remaining EUR100 million is to come from non-G7/EU states, or otherwise also borne by the EBRD.
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Complete report on
Written by Oda Becker on befalf on Greenpeace e.V.
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