A recently released Eskom document revealed that 40 years of exposure to sea air at Koeberg Nuclear Power Station has damaged the concrete of the containment buildings. At one stage the concrete containment dome was found to have cracked around the entire 110 meter circumference.

“The containment buildings are the outer shells of the reactor buildings, built as pressure vessels to withstand the pressure if the reactors inside them ever malfunction and therefore prevent harmful radiation being leaked into the environment,” says DR, a member of Koeberg Alert Alliance (KAA) and a retired analytical chemist.

“Where the chloride salts have entered, they have caused corrosion of the reinforcing steel bars, resulting in spalling and delamination of the concrete – it is even more alarming than I thought,” he says. Spalling results from water entering concrete which forces the surface to peel, pop out, or flake off. An example is shown below.

KAA requests access to information…
The KAA was notified of structural problems at Koeberg by a concerned insider. In August 2020, KAA made two requests under the Promotion of Access to Information Act (PAIA) legislation. The first was a request for the latest report on chloride damage to the concrete reactor containment domes, and the second was related to damage to the stainless steel used in the structures of the plant.

Despite PAIA stipulating that a response must be “as soon as reasonably possible, but in any event within 30 days”, which can be unilaterally extended to 60 days, Eskom did not respond for 143 days.

“Unfortunately this has been the pattern with PAIA requests made to Eskom,” says KAA’s Peter Becker. “Not only was Eskom very slow to respond but what was eventually provided was heavily redacted, with about half the contents blacked out.”

“Eskom frequently uses Covid as the reason for late responses which is becoming a tired excuse. All these documents are in electronic form and instantly retrievable. Perhaps the reason they take so long is the extensive debates they have internally about just how much they can get away with redacting,” says Becker. “They give reasons for the redactions such as ‘Opinion’, and ‘Sensitive technical information’ which do not seem justified.”

“Eskom are aware that to challenge these redactions in court requires a budget of hundreds of thousands of rand, which most civil society organisations cannot afford.”

The provided 31-page report which refers to repairs done up until 2018, has eleven pages entirely blacked out and various other sections, photos and tables redacted with the reason given as “sensitive technical information”.

“The interesting parts are clearly those that have been redacted,” says University of Johannesburg Physics Professor, Hartmut Winkler. “The first big redact is titled History/Background and presumably describes past failures and recent damage that KAA’s PAIA was interrogating. Why should the ‘History’ be sensitive due to technical information when the less redacted sections are full of technical details.

“The most puzzling redact to me are the references which are supposed to be publicly available documents, so why are they all being hidden? Do they expose some entities that Eskom does not want anyone to know have been involved with Koeberg and why? I would also query why the financial information would be redacted. Surely the public has a right to know how much money certain components cost, and what Eskom paid for them?” says Winkler.

Response from civil organisations SAFCEI and OUTA…
According to the Southern African Faith Communities’ Environment Institute’s (SAFCEI) Francesca de Gasparis, “In our experience when submitting numerous PAIA requests over the past year on issues related to nuclear energy, we have found that bodies that are involved in energy decision-making, give an wholly inadequate response.

“Eskom does not view these requests seriously as a civil right. They do not respond with information requested within the required 30-day period, and when they do finally respond, the documents requested are either not given or are heavily redacted. And, while we can understand that certain information is sensitive and must remain confidential, what is unclear is why Eskom redacts information in the documents that would be considered of interest in the public domain,” says De Gasparis.

“What is particularly of concern is that the expenditure for the necessary repairs to the containment structures are redacted,” says Organisation Undoing Tax Abuse (OUTA) Parliamentary Advisor, Liz McDaid. “In effect, this means that we don’t know how much money Eskom has planned to spend on fixing this particular problem so why should South Africans be locked into unknown costs to keep an ageing nuclear power plant going.

“All of these costs will be passed on to the electricity consumer to cough up. Therefore, South Africans need a proper prior informed consent process to decide if they want to extend the life of Koeberg or close it down now,” says McDaid.

Transparency required around Koeberg’s condition…
Eskom’s website claims that “Koeberg’s two reactor containment buildings are made of concrete 1 meter thick, lined with steel. They are designed to ensure that no radiation escapes under any conceivable circumstances, from an earthquake to a jumbo jet collision.”

However, according to the Eskom report: “This (chemical threat) phenomenon was not fully understood when the structures were designed. It is clear that the original designers did not fully comprehend the severe environmental attack which the structures would be subjected to in a harsh marine environment. As such, major reinforcement corrosion has occurred on parts of the outer surfaces, leading to concrete delamination and spalling.”

“What is in the report is deeply disturbing and contradicts claims of safety,” says Becker. “There should be no need to hide the extent of the damage or the associated costs of the repairs. There is a great need for transparency from Eskom as the proposed 20-year extension of Koeberg’s lifespan and additional nuclear builds are being debated.

“It is a well established legal precedent that public participation can only be considered meaningful if the public are fully informed. “By a pattern of delaying and obstructing public access to information, Eskom are pre-emptively undermining the meaningfulness of public participation in the life extension application for Koeberg,” says Becker.

Several engineers were contacted for comment but declined as they hoped to work for Eskom in the future, or had worked for Eskom in the past and signed non-disclosure agreements, or were worried about the implications of being involved. One industry insider willing to comment publicly asked not to be named and just his initials to be used.

What the report does include…
In a section about current versus the optimum scenario, the report begins “The current interventions are neither ideal nor sustainable.”

When discussing mitigation and prevention, the report reads: “The work is not sustainable nor permanent, as the anode (part of the structure which corrodes) ‘moves’ next to where the anode used to be, i.e. the area which the patch repair is applied to. The repairs are non-structural and only about 11% of the structures’ surfaces have been rehabilitated. The areas adjacent to the patched areas will now corrode at an accelerated rate.”

“The containment building is the last line of defence against any breach of the nuclear reactors.”

“It is questionable whether the plant still satisfies the defence in depth safety requirements, given that the containment buildings are experiencing accelerated damage,” says Becker.

No routine maintenance…
The report further states that there is currently “no routine maintenance basis” for the structures with “significant delays to repair concrete degradation with the net result that large patches amounting to approximately 10% of the containment building surface area have delaminated and chloride ingress extends past the rebar cover depth. If left unattended, corrosion of the post tensioning ducts can be expected.”
According to KAA, Eskom has not as yet provided any details on if and when any permanent repairs have taken place since this report has been performed.

The report mentions some remedial work to be carried out. However, the entire section ‘Life Cycle Plan and Expenditure’ has been redacted, so it is unclear what remedial actions are planned.

“Despite the limited information, it seems already clear that these problems persist and patchwork over the years has provided only temporary repair,” says DR. “The vital missing technical information should be included and this is an inadequate response to the PAIA request.”
Koeberg life extension questionable without transparency

Eskom has said it will formally apply to the National Nuclear Regulator (NNR) in 2021 to extend the life of the Koeberg plant 20 years beyond its designed lifetime.

“Koeberg’s safety is a matter of public interest, especially for the 4-million Capetonians who live and work in Koeberg’s shadow,” says environmental sociologist and long-standing observer of the nuclear industry, Dr David Fig.

“If Eskom is not prepared to trust the public with information on Koeberg’s safety problems, how can Eskom expect the public to endorse Eskom’s current plans to extend the life of the reactors?”

De Gasparis concurs: “SAFCEI believes that Eskom’s lack of transparency, in terms of what they share when responding to PAIAs, is hampering citizens’ ability to be more active in the decisions that are being made by government, on their behalf. We feel that the overall poor response to PAIA requests should be seen as a violation of the PAIA Act.”

“By explicitly withholding so much technical information about defects and damage to Koeberg, Eskom is undermining the meaningfulness of any public participation in the life extension licencing process,”says Becker.

In conclusion…
“Given the current containment buildings corroded at an unexpectedly high rate, it makes sense that Koeberg should be permanently shut down as planned in 2024 at the latest,” concludes Becker. “The concrete did not even last the design lifetime, so how can it be expected to last an extra twenty years?”

A major nuclear accident at Koeberg could have devastating consequences for hundreds of thousands of people. Any degradation of the safety features such as the containment building is very much in the public interest, and the lack of transparency by Eskom is a cause for concern. Any public debate about extending the life of the plant needs to be informed by a full disclosure about issues which have been found there so far.

Here is the full report as released: