Cigéo

Cigéo (an acronym for "centre industriel de stockage géologique", or "Industrial Centre for Geological Disposal") is a French project to construct a geological disposal facility for radioactive waste. It is conceived for the disposal of High-level waste (HLW) produced by French nuclear facilities, including during their decommissioning, and by nuclear reprocessing of spent fuel.
The Agence nationale pour la gestion des déchets radioactifs (Andra) is the French national radioactive waste management agency and is responsible for delivery of Cigéo. After more than thirty years of research, including at the Meuse/Haute Marne Underground Research Laboratory, Andra applied in 2023 to ASN, the French nuclear safety authority, for permission to construct the facility.
The Cigéo project is planned for a site several kilometres to the north, at the boundary of the departments of Meuse and Haute-Marne, within the bounds of Ribeaucourt, Bure, Mandres-en-Barrois, and Bonnet, in the drainage basin of the Seine, at the boundary with that of the Meuse. It is intended to site the waste – comprising approximately 83000 m of long-lived HLW and intermediate-level waste (ILW) – in a layer of clay.
The principle of geological disposal was put into French law in 2006. After a, which took place in 2013, the commission concluded that it was not urgent to begin disposal and the timescale for implementation envisaged at the time should be revised. The law defines in parallel alternative disposal routes: long-term storage of radioactive waste, pending final disposal; or separation and transmutation of nuclear wastes into radioisotopes with weaker activity or shorter half-lives.
The estimated cost of the project varies between 15 and 36 billion Euros. The financing, theoretically the responsibility of waste producers, rests partly on the government budget. Social acceptability is one of the major parameters of the project – one billion Euros have been spent to this effect.
Two departmental Public Interest Groups have been created. The Haute-Marne group is presided over by Nicolas Lacroix, president of the Haute-Marne departmental council, and the Meuse group is presided over by Jérôme Dumont, president of the Meuse departmental council.
Since 1996, the project has provoked controversies concerning the financing, the reversibility of the process, uncertainties regarding the capability to guarantee containment of the waste for 100000 years, the volume of waste requiring disposal, and whether the public debate has been genuine or illusory.
The activities of nuclear facilities generate fission products with very high levels of radioactivity and lifetimes in the tens of millennia. Additionally, there are actinides that are less radioactive but have lifetimes in the millions of years, such as neptunium-237, which has a half-life of 2.1 million years, fission products with lower activity such as iodine-129 (half-life of 16 million years), and activation products such as chlorine-36 (half-life of 300000 years). These elements are non-reusable nuclear wastes. In nuclear reprocessing, they are separated from uranium and plutonium, which are potentially reusable.
The strategy for management of long-lived HLW (whether fission products, actinides or activation products) consists of isolating them in places inaccessible to humans for long enough for their radiotoxicity to reduce, the principal challenge residing in the capacity of the facility to contain the radionuclides for a sufficiently long time by menas of different barriers placed between the waste and ecosystems on the surface. One of the options currently retained consists of storing the waste at a depth of 300–500 metres in vaults dug out in a geological layer that is stable, dense and as impervious as possible (e.g. granite, volcanic tuff, or clay, as is envisaged in France). The hazard of the wastes diminishes as their radioactivity decays; the activity of the majority of these wastes will reach background levels in roughly a thousand years.
The dangers of irradiation are poorly quantified for low doses, but according to the international authorities on radioprotection (United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), International Commission on Radiological Protection (ICRP)), the effect is negligible for doses at similar levels to natural background radiation (on the order of a micro-Sievert per hour, or 5mSv/year). On the other hand, according to the IRSN, the radiological impact on people and ecosystems should be evaluated equally in the short or very long term. Underground storage allows the containment of radioactivity over the very long term: groundwater flow being very weak in the impermeable region, only certain mobile radionuclides are able to migrate over a period of tens of millennia, potentially reaching the surface only in extremely small quantities.
Two doctoral theses in 2008 and 2011 on archeological glasses and obsidians estimate that the vitrification process used to immobilise HLW should by itself be capable of assuring containment of radioactive materials for 10000 years.
Nevertheless, for the evaluation of performance of geological disposal, migration models do not take credit for artificial confinement (the containers); only the natural rock is considered. The example of the natural nuclear fission reactors in the Oklo Mine, where non-volatile fission products have only migrated some centimetres in nearly 2 billion years, was used in preparatory works for Yucca Mountain nuclear waste repository to show that confinement over such timescales is possible.
According to a 2017 thesis in the history of science at the School for Advanced Studies in the Social Sciences (EHESS), Andra has had to retreat little by little from attempting to produce a formal proof of the absolute safety of disposal to instead presenting a body of arguments demonstrating that the evolution of Cigéo is controlled in the very long-term.
The region proposed by Andra for the location of Cigéo is in the East of France, at the boundary of the departments of Meuse and Haute-Marne.
Safety performance of a geological disposal site is dependant, among other factors, on the characteristics of the host rock. The geological layer planned for the location of the wastes is the "Callovo-Oxfordian". It consists of a layer of clay rock, about 160 million years old, situated at a depth of around 500 m in the East of the Paris basin (between 420 and 555 m depth at the site of the Bure laboratory. The argilites (a mix of clay and quartz from the Callovo-Oxfordian stages of the Jurassic) possess physico-chemical characteristics which tend to limit the migration of radionuclides. The clay layer, with a thickness of more than 130 m and at a depth of 500 m has revealed excellent containment properties: stable for at least 100 million years, homogenous over several hundred km, the region has very low permeability and is resistant to groundwater flow (the principal cause of degradation of waste containers and dispersion of radionuclides), and the clay has an elevated retention capacity (capacity for sorption of radioactive elements).
During operation of the facility, Andra is aiming at a maximum acceptable dose of 0.25 mSv/year for the public and 5 mSv/year for monitored workers, which is a quarter of the current regulatory limit. For long term, the objective is that the committed dose must remain lower than 0.25 mSv/year for the most affected reference group. Modelled estimates of the dose peak at the 0.0008 mSv/year at the end of 500000 years (dominated by iodine-129 and chlorine-36, which are both soluble); while staying significantly under the objective the dose would be higher (0.02 mSv/year) in the case of hypothetical disposal of "CU1" and "CU2" spent fuel from EdF.
The goal of the Meuse/Haute Marne Underground Research Laboratory was the study of the clay layer, with a view to determining if its characteristics are consistent with the safety objectives of a disposal facility located in the transposition zone.
Andra's work has permitted to show evidence that the properties of the Callovo-Oxfordian argilites will strongly reduce the mobility of actinides and thus the activity flux out of the host rock formation, by confining them in the near field. The ASN nevertheless underlined the necessity of taking into account the residual uncertainties regarding the homogeneity of the clay layer. These uncertainties have been cited by the France Nature Environnement association in justifying its opposition to the project.
The planned facility is composed of surface facilities, notably for receipt and preparation of waste packages or support services for excavation and construction works.
It is envisaged that the wastes will be placed in underground stores situated at a depth of around 500 m, in a layer of clay rock which should be impermeable and have properties which support confinement over the very long term. A funicular railway should enable the waste packages to be taken underground or returned to the surface. The design and eventual construction, maintenance and operation of the funicular have been entrusted to the Grenoble-based Poma, a specialist in cable lifts, for a cost of 68 M€ and with a potential start of operations in 2025 (if the facility is constructed by that point).
Having entered the pre-industrial phase in 2011, the Cigéo project could accept its first waste packages in 2025, after a series of stages and a calendar defined by law. It is planned to operate Cigéo for at least 100 years. The underground disposal tunnels will be constructed progressively, as and when needed. Their footprint will extend to around 15 km after about 100 years of operations.
The law requires that the waste disposal will be reversible for a minimum of 100 years. in order to allow future generations the possibility of modifying or adjusting to disposal process, for example by removal of the stored packages if another "mode of management" is planned or if the safety of the site is called into question. It is not, however, planned to make financial provision to cover some or all of the cost of such a reversal operation.
Cigéo was conceived for the disposal of high-level waste, and long-lived intermediate-level (LL-ILW) waste which could not be disposed of in surface or near-surface disposal facilities for reasons of nuclear safety or radiation protection. For high-level wastes, the dose rate at 1 metre from an unshielded package can be multiple Sieverts per hour at the time of disposal.
The wastes are conditioned in "parcels" by their producer before being placed in a disposal container. The estimated volumes of wastes for disposal at Cigéo are:
The inventory considered by Andra for the conception of the Cigéo project only takes into account nuclear installations that were authorised (or were on the point of being authorised) on 31 December 2010, for a projected operational period of 50 years. However, for waste coming from the current operation of the fleet of nuclear power stations, Andra's reference inventory assumes that all spent fuels will ultimately be completely recycled (including MOX and enriched reprocessed uranium, which are not currently recycled). So, the adjournment of the complete recycling of all spent fuels would have a strong impact on the nature of waste to be stocked, but only towards the end of the century. If it were ultimately decided to dispose of untreated spent fuel in Cigéo, the design would have to be adapted accordingly and the footprint would be expected to increase to around 25 km (9.7 sq mi) (from around 15). Additionally, in the case of complete cessation of nuclear operations, separated plutonium (which could no longer be considered as a recyclable nuclear material but would rather be a waste) would add to the inventory to be taken into account. According to Hervé Kempf, of Reporterre, retreatment, which produces 5 types of wastes (minor actinides, plutonium, spent MOX, reprocessing uranium and spent uranium fuel), should be stopped, storage conditions at the la Hague site should be rediscussed and the project for a spent MOX fuel pool at Belleville-sur-Loire should likewise be rediscussed.
The disposal of wastes from future nuclear installations at Cigéo would be possible, provided they are compatible with the site authorisation (in terms of volume, nature and level of activity. If the inventory to be taken into account exceeds the Cigéo's authorised limits, these should be changed by a modification of the authorisation, the procedure for which would include a public inquiry.
The volumes to be stocked are closely dependent on energy policy, with an increase in the volume expected in the case of early closure of some power stations. The opponents of the project in the public debate in 2013 demanded the adjournment of debate until after the law on the energy transition programme, while ASN recommended, because of these uncertainties, that these "expansion hypotheses" are taken into account.
In order to allow future generations the possibility of revisiting the choice for disposal, the law on the radioactive waste programme states that disposal shall be reversible, as a means of precaution.
The conditions of reversibility are not fixed a priori; they must be discussed during the public debate. After the public debate, the Government will present a bill setting out these conditions, leading to a parliamentary debate; Only then can the authorisation to costruct the storage centre be issued. This authorisation will fix the minimum period during which the reversibility of storage must be ensured; and this duration may not be less than one hundred years
The notion of « reversibility » is relative: it depends on the containers retaining their integrity and the stores being left accessible, but also on the price one is willing to pay for a retrieval operation. Containers which have been placed hundreds of metres below ground and left there for decades or even centuries could perhaps remain technically recoverable, but the cost of doing so under acceptable safety conditions might be prohibitive. Thus, reversibility is considered in progressive stages, including conditioning in containers, emplacement, closure of cells, end of active operations in a storage gallery, backfilling of the gallery, through to the definitive closure of the centre. Each step taken makes reversal a little more difficult and expensive.
Reversibility must be taken into account in the design of the facility: which must facilitate the safe recovery of waste packages, despite the depth, for as long as the facility is not fully closed. To make this recovery possible "in complete safety":
These devices and their maintenance obviously have a cost, all the more important as the requirements for reversibility will be onerous. The question of financing this reversibility is part of the global reflection of intergenerational responsibility. The option taken by the actors of the project is for current generations to finance the laboratory, construction, operation and closure of Cigéo, since only they have chosen this storage method.
For Andra,
Some commentators, such as Jean-Marc Jancovici, believe that reversibility leads to undue complexity.
Evaluation of the total cost of Cigéo must take into account all the costs of storage over more than 100 years: studies, construction of the first structures (surface buildings, shafts, declines (sloped tunnels)), operation (staff, maintenance, energy...), the gradual construction of underground structures, then their closure, their monitoring, etc. Part of these costs/investments will be the salaries of the workforce employed in the digging, construction and storage work, who, according to Andra, will number 1500 to 2000 persons for at least a hundred years.
The cost will theoretically be financed by waste producers (EdF, the CEA and Areva (now Orano)), through agreements with Andra, which will constitute a "fund intended to finance the construction, operation, permanent shutdown, maintenance and monitoring of storage or storage facilities for high- or intermediate-level long-lived waste". For a new nuclear reactor over its entire operating life, this cost represents in the order of 1 to 2% of the total cost of electricity production.
In France, any entity planning to establish or operate a nuclear installation must file a "Safety Options Case".
ASN published a safety guide for final geological disposal of radioactive waste in 2008 and issued several opinions on the file before the 2013 public inquiry (whose conclusions were issued at the beginning of 2014).
After the public debate on the project (end of 2013), Andra announced that it wanted to start operating the storage in 2025, with a "pilot industrial phase" "of 5 to 10 years" preceding a long phase of current operation. On this occasion, it announced that it would submit a safety options file to ASN in 2015, prior to the application for authorisation to construct. This file will include "documents relating to technical recoverability options, draft preliminary package acceptance specifications and a master plan for operations".
On 20 January 2015, ASN replied to Andra by informing it by letter of 19 December 2014 of its expectations regarding the safety options case:
ASN also insists on knowing Andra's subcontracting policy and on seeing in the file an initial draft of the notice provided for in paragraph II Article 8 of the Decree of 2 November 2007 [7] presenting Andra's technical capabilities for the construction and operation of this facility as defined in Article 2.1.1 of the Decree of 7 February 2012, and lists other requirements in an annex to the letter.
ASN's opinion on the safety options case, published on 15 January 2018, confirms the analysis of its technical expert, judging that the project has reached "satisfactory technological maturity". However, it takes up the concerns expressed in the summer of 2017 by the Institute for Radiological Protection and Nuclear Safety (IRSN) on bituminous waste, which represent 16% of the volumes and 18% by number of the packages that Andra plans to store, which would present fire risks. Two solutions are therefore available to Andra with respect to bituminous wastes: treat them to make them inert, for example by a pyrolysis process, or modify the design of Cigéo to avoid a chain reaction in the event of a fire in a package.
In accordance with the 2006 law on radioactive wastes, producers are legally obliged to evaluate the long term costs posed by their wastes and to set aside funds to meet those costs. These expenses are not accounted for in "gross value", but are discounted: dedicated assets are invested and earn financial interest. If, for example, the interest rate is 3.04%, a euro invested today will theoretically yield 1.0304^100=20 € after a century, which makes it possible to balance an expenditure twenty times higher in a hundred years' time.
One difficulty raised by opponents of the project is that, as a result of the discounting, the provisions for charges made by waste producers therefore only very partially cover what the future costs of the storage centre will be, with the balance to be made up by the expected return on investments. The high discount (5% and/or 3%) for long-term charges allows operators to set aside only €5 billion for the Cigeo project, whereas this project is expected to cost at least seven times more. If the cost is under-estimated or the return on investments over-estimated, the fund would be insufficient to cover the cost.
This objection is based on the ability of financial investments to perform over the long term. However, the discount rate used by waste producers is not in fact fixed, but is itself constrained: "it cannot exceed the rate of return, as expected with a high degree of confidence, of the hedging assets, managed with a degree of security and liquidity sufficient to meet their purpose" and must be assessed annually: if the financial return on provisions is lower than expected, producers must reassess their charges (upwards), which unbalances their expense balance. In this case, "the administrative authority notes an insufficiency or inadequacy in the assessment of the charges, the calculation of the provisions or the amount, [and may] prescribe the measures necessary to regularize its situation by setting the deadlines within which it must implement them". Operators are then required to increase provisions to rebalance their long-term expense accounts.
The State has decided not to cover the CEA's expenses from its own assets, but will ensure its financing through the budget; For operators whose costs are mainly long-term, the deadline for complying with this coverage rule has been extended from 2011 to 2014.
The Law of 30 December 1991 on research into the management of radioactive waste organises, over a period of 15 years, research on the management of high-level and long-lived radioactive waste and work according to three families of possible methods:
This law provides that, at the end of a period which may not exceed fifteen years, the government will submit to parliament a global report evaluating this research, accompanied by a draft law authorizing, if necessary, the creation of a storage centre for high-level and long-lived radioactive waste.
In 1992, a call for applications was launched for the choice of departments to host underground laboratories. Thirty applications were received from 11 departments. At the end of 1993, four departments were selected by the government: Gard, Vienne, Meuse and Haute-Marne.
In 1998, after geological and public investigations, the Government of Lionel Jospin opted to build a single laboratory in Bure.
From 1999 to 2004, the Bure underground laboratory was built. In 2005, Andra published the "Argile 2005" (Clay 2005) dossier, which took stock of 15 years of research supplemented by experiments carried out in the underground laboratory, and concluded that it was feasible in principle for the waste to be stored in a geological clay layer, subject to a certain amount of additional research.
In January 2006, the National Commission for the Evaluation of Research on the Management of Radioactive Waste (CNE), created by the 1991 law, published a global report on the results of 15 years of work in preparation for a future bill "authorising, if necessary, the creation of a storage centre for high-level and long-lived radioactive waste". In particular, the CNE recommends "reversible disposal in deep geological situations" which represents the "reference route" for the definitive management of final waste. It also proposes the continuation of research in the underground laboratory located in Bure.
The 2006 law stipulated that the decision whether or not to authorise Cigéo would be preceded by:
The solutions proposed by Andra will be subject to independent control:
The application for authorisation to create Cigéo, which was due to be sent to ASN in 2018, was postponed in 2017 until mid-2019.
At the beginning of 2013, the National Commission for Public Debate (CNDP) prepared the debate on the storage site project. On 4 February 2013, the Minister of Ecology, Delphine Batho, went to Bure to visit the underground laboratory. On 6 February, she validated the dossier prepared by Andra to present the project during the public debate, which was to be held from 15 May to 31 July and from 31 August to 15 October 2013.
For the director of Andra, "the decision to create a storage site in Meuse and Haute-Marne has not yet been taken. [...] On the one hand, [...] it will require the green light from the French Nuclear Safety Authority (ASN). On the other hand, [...] both departments have agreed to the underground laboratory, but they have not yet said 'yes' to the storage centre, and we are perfectly aware of this."
On 15 May 2013, around 40 organisations called for a boycott of the debate, in particular many local groups including Bure Zone Libre, the national federation of Friends of the Earth and the Sortir du nucléaire Network.
On 23 May and again on 18 June, opponents of the project prevented the debates from taking place, believing that decisions had already been taken. The chairman of the Committee for the Debate on this project, Claude Bernet, suspended the session after a quarter of an hour, to the regret of the CNDP, which noted that "many participants had been deprived of their rights to information and expression on the project." Similarly, the Haut comité pour la transparence et l'information sur la sécurité nucléaire (HCTISN) announced that it deplored "these obstacles to the proper conduct of public meetings of the debate, which debate is organized precisely within the framework of the laws of the Republic in order to guarantee a real exercise of democracy."
A poll of residents of Meuse and Haute-Marne showed that 83% of them were in favour of opponents of the project participating in the public debate, but 68% agree with the statement that "the debate will be useless, as the conclusions are known in advance", while considering the debate useful to raise the level of information.
However, Andra declared that "there is no statutory instrument that says that the debate must take the form of public meetings. The National Commission for Public Debate (CNDP) has just proposed alternative solutions, such as adversarial forums on the Internet or a citizens' conference."
On 12 February 2014, the President of the CNDP, Christian Leyrit, proposed to mark out the creation of the industrial centre for the geological disposal of nuclear waste (Cigéo) by starting with a "significant stage" of "pilot storage".
In June 2015, the Conseil constitutionnel (constitutional council) censured the inclusion in the Macron law of an article on reversibility. This was finally included in the law setting the framework for the Cigéo project adopted in July 2016.
On 8 November 2017, at the request of Andra, the CNDP announced the appointment of two guarantors who would support it in the process of informing and involving civil society in the project (Pierre Guinot-Delery and Jean-Michel Stievenard). Given the complexity of the case and the resignation of one of the two guarantors, the CNDP decided on 6 June 2018 to appoint three guarantors (Jean-Michel Stievenard, Marie-Line Meaux and Jean-Daniel Vazelle)
From 2016, the Lejuc wood in Mandres-en-Barrois, on which Cigeo's facilities could be built, became the symbol of the project's protest. It was occupied by activists while the secret ballot of the municipal council of Mandres authorising its transfer to Andra was challenged for formal defects. The ballot was annulled on 28 February 2017 by the Administrative Court of Nancy, which led the city council to meet again on 18 May to confirm its first decision. However, the forest remained occupied by opponents of the project, who were evicted by the gendarmes on 22 February 2018. As the legal remedies on the transfer of the Lejuc wood have not been exhausted, the legality of this eviction is contested by the lawyers of the opponents of the project. In the days that followed, the materials that the opponents had installed in the woods to prevent access and facilitate occupation were removed.
The protests, moreover, sometimes took a violent turn (attempt to set fire to the hotel-restaurant located near the Laboratory, damage to the Court of Bar-le-Duc, threats against parliamentarians and journalists), which led the judiciary to open an investigation into several anti-nuclear activists who had come to settle in Bure and neighbouring villages for criminal association. To this end, it uses criminal analysis methods. Telephone tapping carried out in this context is presented by Reporterre and Mediapart as part of an "inordinate intelligence machine on the anti-nuclear movement", the cost of which is estimated to be around one million euros.
The public inquiry file was filed on August 3, 2020. On 13 January 2021, the Environmental Authority issued its opinion, in which it recommended the presentation of a detailed programme of additional risk management and monitoring studies, while the National Commission for Public Debate (CNDP) stressed the importance of in-depth consultation on the rehabilitation of the Nançois-Tronville-Gondrecourt railway line. In February 2021, the General Secretariat for Investment published a favourable opinion on the Cigéo project, highlighting the "strong prudential and insurance value" of the project, while pointing out the "significant and serious risk of cost drift".
As the public inquiry file was updated to reflect these recommendations, the inquiry was launched on 9 August 2021 and ran from 15 September to 23 October. On 20 December, the investigating commissioners gave an opinion "unreservedly" in favour of the declaration of public utility and the compatibility of the urban planning documents.
On July 8, 2022, the declaration of public utility (DUP) for the Cigéo project was published by decree. This DUP will allow the urban planning documents to be brought into compliance and the acquisition by the National Agency for the Management of Radioactive Waste (Andra) of the necessary land by expropriation. The decree specifies that the expropriations of land necessary for the realization of the project will be "carried out before 31 December 2037", and those "concerning only the subterranean [aspects] [...] no later than 31 December 2050".
On 17 January 2023, Andra submitted the application for authorisation to create the Cigéo site to the Ministry of Energy Transition. The Nuclear Safety Authority has five years to examine the file and decide whether or not to authorise the creation of the site.