ASN Report 2018

For civil facilities undergoing decommissioning, the main challenges concern the La Hague site facilities. The licensee has put in place operational provisions for extinguishing a fire in silo 130 following a “hardened safety core” earthquake (1) . Silo 115 must also be further protected against fire risk and ASN has asked the licensee to study measures to speed up implementation of this programme. Integration of the lessons learned from the Fukushima accident for the facilities presenting more limited risks shall be assessed by ASN at the next periodic safety reviews. Lastly, there is no reason to perform stress tests on facilities which are nearing the end of decommissioning and will soon be delicensed. 3.3  ̶  The periodic safety reviews of facilities undergoing decommissioning Licensees of basic nuclear installations conduct periodic safety review of their facilities, even if they have been definitively shut down and are undergoing decommissioning. This review is designed to assess the status of the facility with respect to the applicable regulations and to update the assessment of the risks or drawbacks of the facility, taking into account the condition of the facility, acquired operating experience, changes in knowledge and the rules applicable to similar facilities. For facilities whose final shutdown is announced, the safety review provides the opportunity to prepare for decommissioning by detailing the decommissioning plan, which must be regularly updated during the life of the facility. In this case the aim of the safety review is to ascertain the acceptability of the safety of the changes in the facilities resulting from the decommissioning work, of the quantities and nature of the radionuclides and other hazardous substances present in the facility, as well as the nature of the ageing of the facility. The ageing assessment is carried out with respect to the envisaged decommissioning completion time, and must take into account margins to allow for decommissioning project contingencies. For facilities in which the radioactive substance removal and decommissioning times are well under control, it may be acceptable not to apply the same requirements as on recent facilities that are in operation. The conformity check aims to ensure that the changes in the facility due to the decommissioning work or to ageing do not call into question its conformity with the provisions of the regulatory texts and its technical baseline requirements. Given the diversity of the facilities and the situations involved, each periodic safety review must be individually examined by ASN. ASN applies a method of examination that is adapted to the risks inherent to the facilities: some facilities require particular attention due to the risks they present; for others presenting a lower level of risk, the extent of the inspections and examinations is adapted accordingly. In 2018, ASN continued the examination of the safety review conclusion reports of some thirty facilities undergoing decommissioning. This examination in 2018 of the reports received in 2017 revealed no major deficiencies in the documents, but ASN nevertheless did have to request additional information or technical supporting evidence for the majority of the files in order to continue their examination. 1. Earthquake considered for the equipment forming the "hardened safety core" of the facilities. The term "hardened safety core" was defined after the Fukushima NPP accident to identify the ultimate equipment controlling the vital safety functions in an extreme situation (earthquake, winds, tornado, extreme flooding, etc.). 3.4  ̶  Financing decommissioning: ASN’s opinion on the triennial reports The regulatory framework for ring-fencing the funds necessary for management of the long-term decommissioning and waste management expenses is presented in chapter 14. On 8 June 2017, ASN published opinion CODEP- CLG-2017-022588 relative to the examination of the three- yearly reports submitted in 2016 by the licensees, concerning the accounts closed at the end of 2015. With regard to the evaluation methodology, ASN had noted disparities in the levels of detail of the submitted reports. More specifically, the EDF triennial report did not provide sufficient information for ASN to adopt a position. EDF does not present its expenses evaluation reactor by reactor, yet some situations do display particularities (taking into account the operating history, the post-operational clean-out of the structures and soils, etc.). Nor does the information provided allow an assessment of the envisaged savings resulting from the experience acquired in the decommissioning of technologically similar reactors. ASN had also noted that some decommissioning scenarios were based on the assumption that the radioactive waste and spent fuel treatment facilities would be available when required, and pointed out the need to assess the impact of these facilities not being available on the projected date. ASN recommended that for these facilities which must be created, the licensees take into consideration the hypotheses concerning their construction, operation and decommissioning. With regard to the cleaning out of the civil engineering structures and remediation of soils, ASN noted that few licensees took sufficient account of the cost of soil remediation in their evaluation. Lastly, ASN noted that the cost of facility modifications, resulting in particular from the stress tests and the works for continued operation (periodic safety reviews and EDF’s “ grand carénage ” overhaul programme), were generally not explicitly taken into account. The licensees update these evaluations annually. In 2018, as in 2017, ASN noted a lack of detail in the information provided by EDF and the need to assess the impact should the facilities required for decommissioning not be available on the projected date. ASN also noted little change in the structural clean-out and contaminated soil management procedures with respect to the three-yearly reports submitted in 2016. Lastly, ASN considers that the licensees must supplement the expenses evaluation by including the cost of the decommissioning preparation operations. 344  ASN report on the state of nuclear safety and radiation protection in France in 2018 13 – DECOMMISSIONING OF BASIC NUCLEAR INSTALLATIONS