The concrete issue in the nuclear reactors Doel 3, Doel 4, Tihange 2 and Tihange 3 has been classified at the lowest level (an “anomaly”) on the International Nuclear Event Scale (“INES”). The Federal Agency for Nuclear Control (“AFCN”) indicated so on Friday. The INES, which goes from 1 to 7 (major accident), enables the determination of the significance of an event involving ionizing radiation sources. The AFCN stresses that the issue of concrete, which itself has no impact upon the population, workers and the environment, is calling into question the lack of availability of fail-safe systems, which is increasing the risks in the event of an external accident.
During its scheduled stoppage this month, concrete damage was observed at the level of the bunker ceiling of the reactor Doel 3. Similar damage has been observed in the reactors with the same bunker concept: Tihange 3, Doel 4 and Tihange 2. The agency mentions that the damage is requiring significant repair of the concrete on the roofs of these bunkers.
The concrete damage is linked to the specific function of part of these bunkers. Some facilities have had significant vapour release. The vapour exposes the concrete to warm and humid conditions, which in the end has led to the damage.
The cleaning of the damaged areas has also caused the appearance at Tihange 2 and 3 of anomalies as regards positioning of the concrete armatures of the framework of the bunker, present since the construction of the building.
These buildings house fail-safe systems. So that the operation of these systems is guaranteed at all times, the building must be able to resist external events. The AFCN concludes the scale of the damage and anomalies call into question the resistance of these buildings when faced with an outside accident, such as an aeroplane coming down.