ASN Report 2017

443 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 16  - Radioactive waste and contaminated sites and soils reached by 2025-2030, ASN considers that Andra must examine the possibility and conditions of increasing the volume capacity of Cires without changing its ground coverage area and, subject to these conditions being favourable, filing the corresponding modification application as soon as possible. ASN considers that a second VLL waste disposal facility will ultimately be necessary to maintain the availability of disposal capacities for this waste. ASN also considers that VLL waste producers must engage in an approach that allows an in-depth examination of the feasibility of creating disposal facilities appropriate for certain types of VLL waste on their sites. ASN considers moreover that the management of VLL radioactive waste in France must continue to be based on the place of origin of the waste and guarantee its traceability, by means of specific routes, from production to disposal. ASN also considers that the possibilities of recycling very- low-level materials within the nuclear sector must studied exhaustively before considering other outlets. These positions are formalised in ASN opinion 2016-AV-0258 of 18th February 2016. 1.3.2 Disposal of Low and Intermediate-Level, Short-Lived (LL/ILW-SL) waste The majority of LL/ILW-SL waste is placed in surface disposal facilities operated by Andra. Once these facilities are closed, they are subject to monitoring for a period set by convention at 300 years. The facility safety analysis reports – which are updated periodically, including during the monitoring phase – must show that at the end of this phase the residual activity contained in the waste will have reached a residual level such that human and environmental exposure levels are acceptable, even in the event of a significant loss of the containment properties of the facility. There are two such repositories in France. FUNDAMENTALS The periodic safety review of the CSA Andra carried out the periodic safety review of the Aube Waste Repository (CSA) until August 2016 when it submitted the conclusions report to ASN. ASN conducted an initial analysis of this file, which resulted in the licensee being asked for additional information and referral to the Advisory Committee for Laboratories and Plants (GPU) and the Advisory Committee for Waste (GPD). The identified issues concern the safety functions to be fulfilled by the civil engineering structure and the CSA equipment: control of chain nuclear reactions, containment of harmful substances (radioactive substances in particular) and protection of people and the environment against ionising radiation. The Advisory Committees gave their opinions on 8th February 2018. The periodic safety reviews provide the opportunity to assess the conformity of the facility, the upgrades or improvements proposed by the licensee or requested by ASN, taking into account the ageing of the facility and its equipment, particularly in the areas in which the regulations and safety requirements have evolved. The subjects examined with particular scrutiny in the periodic safety review of the CSA are: ཛྷ ཛྷ control of the risks associated with internal and external hazards: -- fire, particularly in the Waste Packaging Unit (ACD); -- earthquake, particularly the levels of seismic risk proposed by Andra during operation and during the surveillance phase for the various CSA buildings, and the resulting reinforcement of certain premises in the ACD; ཛྷ ཛྷ the long-term impact of the chemical substances, particular those contained in the stored packages; ཛྷ ཛྷ the technical characteristics of the long-term cover of the repository; ཛྷ ཛྷ the reassessment of the ultimate inventory of the waste; ཛྷ ཛྷ the positioning of the disposal structures with respect to the highest water level; ཛྷ ཛྷ the package acceptance specifications, particularly for sealed sources. The CSA periodic safety review takes into consideration the technical particularities of the disposal facilities and the risks during the operating phase and after closure of the repository. It has induced Andra to define measures to reinforce the safety of the repository, and to prevent and mitigate its environmental impacts. ASN is preparing a resolution to be issued in 2018 governing the continued operation of the CSA; this resolution will modify the current provisions applicable to the CSA if necessary. ASN will transmit an analysis report to the Minister responsible for Nuclear Safety on the fitness of the repository for continued operation after its periodic safety review, and more specifically until the next one.