- 32 - Furthermore, even though some training had been given, the exercises initiated by ASN during the inspections demonstrated that on most sites, the operators liable to have to use the data from the seismic instrumentation had little if any ability to do so, which could also delay reactor shutdown or even lead to this decision not being taken. ASN finds that EDF needs to overhaul its organisation (equipment and procedures) and its staff awareness and training, to ensure conformity with RFS I.3.b and its objectives. EDF informed ASN that it has already initiated measures to address ASN's findings (verification of positioning of seismic measurement sensors, operator information, updating of procedures). ASN finds that verification of the effectiveness of the procedures entails the performance of realistic exercises. This type of exercise is not currently held. This programme of exercises should also take into account the experience feedback from the Fukushima accident, in other words should take into account the hazards resulting from an earthquake (fire, explosion, industrial risk, mobilisation of the public services, absence of communication routes) and the known vulnerabilities of the facility (for example, on some sites, emergency buildings not designed to withstand a SSE). ASN also considers that EDF must for all its sites identify the general resources that are essential in the event of an earthquake on the site and check that these resources (both on and off the site) are robust enough to withstand the safe shutdown earthquake as defined in the safety reports. As applicable, other resources shall be defined in a PUI (radiological or other) and deployed. The inspections and in particular the field visits, clearly showed the need to improve awareness and good practices with respect to the approach for the earthquake event. ASN finds that EDF needs to develop and implement an appropriate training programme on this topic and update the site documents (in particular the risk analyses). The national reports will need to be applied as rapidly as possible. EDF informed ASN that it has already taken steps to address the ASN findings (nomination of a local seismic coordinator, seismic risk awareness-raising campaigns launched on all the sites). Finally, ASN finds that certain sites must more rigorously monitor the discrepancies concerning the seismic resistance of certain equipment and perform an overall analysis of the impact of these discrepancies. 1.32.3 Loss of heat sink 2.3.1 Introduction Reactor cooling is a function important for the safety of a nuclear facility. To prevent the dispersion of radioactivity, the cladding surrounding the nuclear fuel must be prevented from bursting and the fuel from melting. This in particular requires removal of the heat given off by the nuclear reaction and the residual heat remaining after the chain reaction is stopped. This function is performed by a system which pumps in cold water from an outside source (sea or river). The water in the cooling system is then either sent directly back into the environment or, when the river discharge is too low or the heating too high given the sensitivity of the environment, it is cooled in a cooling tower. The goal of the inspections was two-fold. The first goal was, following the national inspection campaign on this topic in 2007, to check the conformity of the facilities with the EDF "heat sink" frame of reference requirements currently applied to the French nuclear power plants. Various natural or climatic hazards such as drought or large-scale arrival of clogging material have also in recent years had consequences on the heat sinks of French NPPs. The second goal of the inspections was thus to assess the extent to which EDF has taken into account experience feedback and effectively deployed countermeasures and procedures for dealing with comparable hazards. 2.3.2 Organisation / human factors The aim was to check that the sites are correctly organised so that they can integrate and locally apply the requirements of the national frame of reference. The relations between the site and the head office departments were examined. The distribution of responsibilities within the sites was investigated. EDF has set up a national network of "heat sink" correspondents in each NPP. ASN observed disparities in the organisations put into place for monitoring the "heat sink" system equipment. Most of the sites have their own heat sink engineer specifically dedicated to monitoring this equipment, but this type of
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