Paks II. NPP site should be moved because it sits right at tectonic fault line, says expert
In an interview with Atlatszo Professor Gábor Timár, head of the Department of Geophysics and Space Science at Eötvös Loránd University says that a tectonic fault line is not only close to the planned site of the Paks II plant but runs right under it. Timár says that the plant should be built at least one hundred meters to the north of the originally planned site so that it does not directly sit on the fault line.
Atlatszo.hu has revealed that a tectonic fault line runs under the site of the planned Paks II nuclear plant. Moreover, a geologist found traces of earthquakes that happened less than hundred thousand years ago and reached the surface. That is, the site does not comply with IAEA seismic hazards recommendations. This information was not available to the public until Atlatszo filed a freedom of information request and received the documentation of the latest geological inspection.
In the interview, Timar says that Hungary is situated in an area where earthquakes do happen, even though they are rare. The geological inspection of the site of a planned nuclear plant has to decide two things: one of them is whether an earthquake big enough to damage the structure of the plant is likely. Timar says this is not the case at Paks and this makes a Chernobyl- or Fukushima-like catastrophe unlikely.
The second question is how much collateral damage an earthquake could do. Nuclear reactors are enclosed by a containment structure, a gas-tight shell to confine fission products that otherwise might be released to the atmosphere in the event of an accident. If this structure is damaged by an earthquake, it is either very expensive or impossible to fix it. Any damage of this containment structure is an unfixable problem. To avoid the risk of an earthquake damaging the containment, Timar says that the whole structure should be built to the north of the currently planned site because it is directly on the fault line that was found by the latest geological inspection.
Huge earthquakes are not likely at Paks, but according to Timar even a small earthquake is enough to damage the containment if it sits right on the tectonic fault line.
Timar explained that even though the probability of an earthquake is very low, the cost of the damage done to the nuclear plant would be so high that even the smallest probabilities have to be studied. However, these probabilities are so low that they are hard to comprehend even by mathematical methods used by experts. The reason why the country is spending a huge amount of money (HUF 8 billion) on a geological inspection is to be able to try and get closer to quantifying that probability.
“The whole point of the inspection was to decide whether we can or cannot build a new nuclear plant at that site, but that decision had been made before the start of the geological inspection and the results have no retroactive effect on that decision” says Timár.
He doubts whether it is still possible to change the plans and push the whole structure 100 meters to the north, off the tectonic fault line. “The research was done after the decision had been made” he says.
Timár says that the geological inspection was professional and unbiased. It found the fault line, documented it and included the results in the final report. However, the committee, in the end, made the decision that the site was fine and gave the green light to the construction. Their keyword is “capability”, that is, they are asking if the fault line is “capable” of causing damage. Timar told Atlatszo that this is the first time he heard of this expression in a geological context.
“We are on thin ice here” Timar says. “I agree that there is a small chance that the fault line will cause trouble during the operation of the nuclear plant, but is it small enough compared to the damage it can do?”
Written by Tamás Bodoky
You can read the full interview in Hungarian here.