Andra is currently working on the Acaci project, the objective of which is to increase the authorized disposal capacity of very low-level waste (VLLW) at the industrial center for grouping, storage and disposal (Cires), without changing the existing disposal area of the site.
The "Acaci" project: anticipating the volumes of waste to be disposed of
One of the solutions studied consists in increasing the authorized storage capacity of Cires. This project, named "Acaci" - for Increasing the CApacity of CIres - would therefore aim, without changing the site's existing disposal area and while maintaining its current level of safety, to increase its disposal capacities by nearly 50%.
This project relies on an optimization of disposal at Cires which has been implemented for several years already. "As the center is in operation, we have sought to anticipate the increase in future volumes of VLL waste, by optimizing storage", explains Patrice Torres. The revisions to the design of the disposal cells and the disposal arrangements (diagram below) have indeed enabled a disposal gain of 56% compared to the initial concept. "This concept provided for diposaing the 650,000 m3 of authorized waste in three zones. Thanks to these optimizations, we will only use two zones. The third will therefore be free and would allow us, if we have the authorization, to accept some 250,000 m3 to 280,000 m3 of additional waste, for a total of more than 900,000 m3 for the same area. "
Andra has been working on the Acaci project since 2018. "The PNGMDR * 2016-2018 required us to submit an authorization request six years before the capacity of the center is reached (estimated in 2028)", specifies the director. In the meantime, the studies and regulatory steps related to this project will have to manage various industrial, technical, environmental issues and dialogue with stakeholders, including the public, in order to continue operating Cires under optimal conditions (read below (below the interview with Fanny Gérard).
"Not only would this project give us ten years of additional disposal capacity, which is already a lot, but it would also give us more time to concurantly assess, the relevance of other solutions for managing this waste, which '' it is the construction of a new facility for which we are conducting studies to find a site on the territory of the community of communes of Vendeuvre-Soulaines, or the disposal of part of the VLL waste on their production sites (in situ disposal) or the recycling in the nuclear sector of part of the waste, in particular metal waste.It is important to anticipate, but also to move forward step by step, leaving the debate onVLL waste management open to decisions that our successors could take, ”concludes Patrice Torres.
* PNGMDR: every three years, the Government and the Nuclear Safety Authority establish a National Radioactive Materials and Waste Management Plan (PNGMDR). This management tool takes stock of the management methods existing in France for radioactive materials and waste, it identifies the foreseeable needs for warehousing or disposal facilities, and defines strategic orientations.
Two diagrams to understand
Deepening, stiffening and widening of the slopes of the storage cells, increase in the total height of waste stacking: the optimization of CIRES has made it possible to save 56% of the storage surface by increasing the volume ratio of waste stored on the surface used
The initial CIRES Project planned to dispose of 650,00 m3 of VLL waste in 3 construction successive lots (T1, T2, T3). Thanks to optimizations in the disposal methodologies, only 2 lots will be necessary until 2028. The ACACI Project will allow the disposal of between 250,000 and 280,000 m3 on the 3rd lot, bringing the total capacity over 900,000m3.
Very Low Level waste: what the legislation says
Today, French regulations consider that any waste produced in a nuclear zone is radioactive waste and must be managed as such in a specific sector, even if the controls do not show any radioactivity or at a very low level. . This is the case, for example, with certain metal waste or rubble, concrete from nuclear installations.
Like other countries, France is considering adjusting its regulations in order to be able to recycle part of this waste within the nuclear sector.
INTERVIEW: one project, several scenarios to study
The Acaci project will be the subject of in-depth studies and a regulatory procedure specific to any ICPE *. Objective: to define, in connection with the territory, the best development options to minimize the impact of the project on humans and the environment. Update on the project with Fanny Gérard, project manager at Andra.
What are the main technical challenges of the Acaci project?
In terms of design, this third disposal area for Cires will not be very different from the other two areas. We will reproduce the current concept of storage cells, taking into account all the optimizations from which the facility has already benefited. In contrast, one of the major issues, as with most civil engineering projects, is that of land management. The digging of the disposal cells generates a lot of materials that we have to store, before reusing it for the final cover of the disposal. Several options are being studied: using industrial or agricultural land near the center, clearing part of our land adjacent to the Center, etc. We are carrying out analyzes of the best overall scenarios, according to environmental, industrial, legal, economic and other criteria, like the impact on the neighborhood, which can be discussed with residents. Andra wants to involve the local population in this project by organizing a consultation prior to filing the authorization request to increase the disposal capacity of Cires.
Does increasing the disposal capacity for even very low-level waste mean increasing the amount of radioactivity in the facility?
Yes, that is why our current studies evaluate the impact of the project on humans and the environment during all phases of the facility's life (construction, operation, closure). To do this, we will develop an inventory of future VLL waste, on the basis of which we will recalculate the radiological and chemical impacts of the entire facility. However, it should be noted that today, after disposaing of around 400,000 m3 of waste packages, or around 61% of the total currently authorized capacity of Cires, we have "consumed" less than 10% of the authorized radiological capacity ** . We are therefore not going to consume the remaining 90% by increasing the volume of waste stored on the CIRES by 50%. In all cases, we will reassess the impact of the facility to ensure that its capacity limits are respected.
"We are now working to identify the topics specific to Unit 3 to discuss them with the public"
Where is the project today and what are the next steps?
We have been working on the design studies for the project since 2018: design, development, environmental impact studies, etc. They will feed into the environmental authorization application file that we will submit to the prefecture in mid-2022. Before that, we will be launching a cycle of meetings with the public in 2021. As this is an operating facility and a concept that has already been tested, we are now working to identify specific topics for this project to discuss with local residents. The next step after the consultation phase will be the filing of the authorization application file with the prefecture. It will then take between nine months and two years of investigation by the state authorities, during which a public inquiry will be carried out. If the project is authorized, around four years of work will be necessary for unit 3 of Cires to take over from unit 2 by 2028.
* Installation classified for environmental protection / ** for the majority of radionuclides (except two radionuclides whose consumption amounts to 20% and 32%)