France is working on an underground repository for permanent disposal of radioactive waste. The Industrial Geological Storage Center (Cigéo) will be located in a system of tunnels in a natural layer of clay in Meuse/Haute Marne east of Paris. EDF, Areva and the French Alternative Energies and Atomic Energy Commission are generators of radioactive waste in France including spent nuclear fuel. They will provide the financing for the repository which will be managed by the waste management agency Andra. The application to regulators will be submitted by the end of 2018. Construction will follow in 2020. Actual disposal of waste in the repository could begin as early as 2025.
Andra has submitted a “safety options dossier” about the Cigéo to the Nuclear Safety Authority (ASN), the French nuclear regulatory agency. This document details objectives, concepts and principles that will be employed to insure that the repository is operated in a safe and efficient manner. The document allows Andra to seek advice from the ASN as they prepare the portion of the license that involves safety protocols at the repository.
The ASN technical division, Institute for Radiological Protection and Nuclear Safety (IRSN), was asked to review the “safety options dossier”. Their main goal was to “assess the project's maturity status in order to judge the relevance of the options selected, from the point of view of safety and radiation protection”. The IRSN drafted a report to the ASN after a series of technical meetings with Andra and other stakeholders. The IRSN concluded that the Cigéo project has "overall achieved satisfactory technical maturity at the stage of a safety options dossier and underlines the substantial design and research undertaken by Andra with a view to demonstrate the safety of the installation". The report from the IRSN did highlighted some areas of concern that may impact the design of the Cigéo repository.
The IRSN expressed a concern that the design of the facility must be optimized to insure that radioactive material cannot be not released into the environment. The IRSN also said that monitoring systems should be installed to track risk of problems developing. The operators should also be able to intervene “to manage situations likely to lead to contamination of infrastructures”.
There is a danger of fire in a chamber that will store bituminous waste. The IRSN said that this was their biggest concern and that the Andra design does not have enough safety guarantees. About eighteen percent of the waste to be stored at Cigéo will contain bituminous materials. The IRSN report said that “The problem is that in the event of a fire [the packages of bituminous waste] rise in temperature and are likely to spread a heat wave and eventually spread the fire.”
The IRSN suggests that Andra and the creators of radioactive waste consider pre-treating waste containing bituminous materials in order to remove its thermal reactivity. Andra could also change their design to prevent the spread of a fire if it should occur. The IRSN said, “In this respect, the work to be carried out by Andra on these issues could have an impact on the outline of the [application for authorization to set up a nuclear installation] or the associated delays.”
The ASN requested that the International Atomic Energy Agency (IAEA) carry out a peer review of the Cigéo “safety options dossier.” The IAEA reported that it found that Andra’s methodology for evaluating operational safety was comprehensive and systematic. The ASN will soon issue its conclusions with respect to the dossier. The IAEA, IRSN, ASN and Andra will use the reviews of the “safety options dossier” to guide the drafting of the actual license application for the repository.
