The news remained discreetly buried in the depths of the site of the French Nuclear Safety Authority (ASN): Following recent studies, EDF has just "discovered" a disturbing "anomaly" standard on 34 of its reactors. In all reactors of 900 MW in case of major leakage from the primary circuit, the water injection safety circuit may be unable to prevent the meltdown of the reactor core.
The Nuclear Safety Authority (ASN) warns: "In an accident situation, for breach of certain sizes of primary pressure, the injection from the high pressure safety system may not be sufficient enough to cool the reactor core" (i) ..
The water injection security system is the only device that allows to delay a nuclear meltdown if there is a major leakage of primary circuit water. Its role is to inject massive quantities of boron water (ii) in this circuit to suppress the nuclear reaction and cool the core.
So EDF has discovered this while the first series of 900 MW reactors have been running for over 30 years (iii), it is unable to assess whether the injected water through the system is uniformly distributed in the three loops of the primary circuit of the reactor; the ASN has admitted ,"it might not allow sufficient cooling of the reactor core" (iv).EDF has let 34 nuclear reactors run for a quarter of a century before to ensure the effectiveness of this primary prevention system against nuclear meltdown.
Why has this discovery occurred so late? It is extremely disturbing that a problem of this magnitude has been ignored for so long by EDF ...
The plants concerned are: Blaye (Gironde), Bugey (Ain), Chinon (Indre-et-Loire) Cruas (Ardèche), Dampierre (Loiret), Fessenheim (Haut-Rhin), Gravelines (Nord), Saint- Laurent des Eaux (Loir-et-Cher), Tricastin (Drôme). Or all of the thirty four 900 MW nuclear reactors, some of which have already reached 30 years of operation. EDF has put all its eggs in one basket, multiplying the risks as they go along....
Under the precautionary principle, the Network "Sortir du nucléaire" demands the closure of the reactors concerned
An accident caused by these "anomalies" would have catastrophic consequences. In a context where security concerns are increasing in recent years (v), this possibility must always be taken into account. Especially considering that 21 reactors run on MOX fuel containing plutonium.
More than ever, the discovery of these failures shows vividly the need for a political energy transition as quickly as possible, to finally get out of the French nuclear risk imposed on the population for decades.In light of these security deficiencies, the Network "Sortir du nucléaire" has requested that the ASN plays its role, in requiring EDF, under the precautionary principle (vi), the closure without delay of the 34 reactors concerned.
Steven Mitchell +33 (0)952 495 022
Sortir du nucléaire +33 (0)478 282 922
i. Link to the opinion of the DSC security flaw:
ii. The borated water serves to moderate the nuclear reaction in the core.
iii. The first reactor of 900 MW was connected to the grid in April 1977, the Central Fessenheim (Alsace). The last of the 34 900 MW reactor was connected to the power grid in November 1987 at the Central Chinon (Indre-et-Loire).
v. Report "The view of the IRSN on the safety and radiation protection of French nuclear power plants in 2009"
vi. The precautionary principle is constitutional since the integration of the Environmental Charter into the Constitution in 2005