Solutions for Low-Level, Long-Lived waste (LL-LLW)
Andra is developing solutions for the disposal of LL-LLW, for which there is currently no evacuation route. While not accepted in surface-based storage facilities because of its long-lived radionuclide activity, the low specific activity of LL-LLW does not justify storage at 500 m depth in Cigéo
Low-level long-lived waste (LLW-LL) makes up 6% of the total volume of French radioactive waste. It mainly comes from:
- processing various ores used, for example, in the fine metallurgy and electronics industries (radium-bearing waste),
- dismantling the nine first-generation graphite-moderated gas-cooled nuclear reactors built in France (graphite waste).
It also includes objects, some of which are quite old, whose manufacture required the use of radioactive substances, for example, watches, alarm clocks, lightning conductor rods, as well as waste from cleanup operations at disused sites contaminated with radioactivity.
All this waste is low-level radioactive waste but, in some cases, it will remain active for hundreds of thousands of years. In most cases, this type of waste is no longer produced. Such waste is stored at the sites where it was produced, pending the development of a final disposal solution.
Designing a suitable solution proportionate to the risk
Large quantities of LLW-LL cannot be disposed of in the surface disposal facilities at Andra's Aube industrial facilities because of the long half-lives involved, but it is not so hazardous that there is any justification in systematically disposing of it 500 m underground at the Cigeo Industrial Centre for Geological Disposal.
A suitable disposal solution that is proportionate to the safety risks posed by such waste therefore needs to be developed.
This solution must meet various technical requirements (choice of a site, knowledge of the waste, disposal facility design), and be aligned with the waste producers' strategy for dismantling their facilities and storing their waste, as well as addressing ethical and societal issues regarding such waste, which while it does not present a serious hazard, will remain radioactive for a very long time.
Key stages of the project
Under the Planning Act of 28 June 2006, the French government assigned Andra the task of finding disposal solutions for graphite waste and radium-bearing waste.
2008-2012: a national campaign was launched but proved inconclusive
In 2008, and based on a geological survey conducted by the French Geological Survey (BRGM), Andra, with approval from the French government, launched a call for applications across France. 3,115 municipalities located in districts where the geology was potentially compatible with the siting of a near-surface disposal facility were contacted.
Around forty municipalities expressed an interest in the project. After being analysed by Andra and after consulting the French Nuclear Safety Authority (ASN), the National Assessment Board (CNE) and elected officials representing the municipalities in question, the government asked Andra in 2009 to conduct in-depth geological investigations in two municipalities. However, the latter both withdrew their applications in the summer of 2009 under pressure from people opposed to the project.
In this context, the government asked Andra to pursue discussions with regions in which municipalities had expressed an interest.
The High Committee for Transparency and Information on Nuclear Safety (HCTISN) set up a working group to draw up recommendations for continuing the campaign to find a site. The group's recommendations, published in 2011, cover the selection of a site, a schedule, responsibilities, local stakeholders, public information, consultation and support for the project. In particular, the High Committee recommended:
- using the results of the 2008 call for applications;
- prioritising the choice of regions in which nuclear facilities already exist;
- holding discussions at the very least at intercommunal level, supported by the government and larger local authorities.
In 2012, and based on these recommendations, Andra submitted a report on the long-term management scenarios for LLW-LL. This report pointed to the need to initiate geological investigations in order to move forward with the design of a near-surface disposal facility project. Andra submitted the 2012 report to the local authorities of the municipalities that had expressed their interest following the 2008 call for applications, making it known that the Agency was available to present the ongoing campaign and learn what their intentions were.
2013-2015: taking the project further and the geological investigations
In 2013, following on from the campaign, the Soulaines intercommunal authority gave the go-ahead for geological investigations to be conducted in the area, although this did not imply approval for siting a future disposal centre there. The other local authorities did not renew their interest.
The government asked Andra to conduct scientific investigations in the Soulaines district to assess the feasibility of building a disposal facility for LLW-LL, to which a facility for the disposal of very low-level waste could be added. All this was subject to a requirement to set up a consultation and information process prior to any activity in the district. A consultation body was set up in mid-2013 to define support measures for the possible siting of a new disposal facility. Chaired by the Prefect for the Aube, this body is made up of local elected officials, representatives of the producers of LLW-LL, government departments and Andra. At the same time, a geological survey campaign was carried out in 2013-2015 in a 50 km2 sector encompassing five municipalities.
In 2015, Andra submitted a status report on the near-surface disposal facility for LLW-LL at the site investigated to the government. This report set out what had been learned from the initial geological investigations carried out, and described the progress made on the studies and research on waste conducted by Andra and the waste producers (EDF, CEA, AREVA, and Solvay). Preliminary design studies had been carried out and a first safety assessment completed. At the same time, analysis of the different management scenarios relating to graphite waste and bituminised LLW-LL was being conducted by the working group on optimising waste management solutions set up under the National Radioactive Materials and Waste Management Plan (PNGMDR). The 2015 status report identifies a small area suitable for developing the project, as well as various topics to be investigated further in pursuing the research and studies.
Under the 2016-2018 National Radioactive Materials and Waste Management Plan, and following on from the 2015 report, Andra was asked to submit an overall industrial plan for managing all LLW-LL by the end of 2019. This plan must integrate new input data identified since 2015: the ASN's Opinion on the 2015 report, the request to include new waste in the inventory for the project, changes in producers' dismantling and cleanup strategies, and, in particular, the new timetable announced.
To draw up this industrial plan, Andra has, since May 2017, been conducting further geological investigations in the zone of interest proposed in 2015. In liaison with the waste producers, Andra is also conducting studies on the radiological inventory of this waste and on controlling its behaviour in disposal conditions. At the same time, Andra has integrated in its studies the possibility of developing a disposal area for very low-level waste (VLLW) at the future disposal facility for LLW-LL. Given the forecast volume of VLLW that will be produced during future dismantling operations, new disposal capacity must now be planned, and this may involve developing synergy with Andra's existing facilities in the Aube.