| I. Materials > The Uranium-Plutonium Chain > Waste Disposal |
The three categories of radioactive waste, for which the management is regulated, are determined by the radioactivity, nature, and half-life of the isotopes that they contain. We emphasize, however, that the categories A, B, and C such as they are defined by the CNE (see below) do not correspond to actual regulatory categories. In other words, there is no regulatory text that defines categories A, B, and C.
Category A: wastes of low- and medium-activity mainly containing short- or medium-lived beta-gamma emitters and alpha emitters in small quantity (no more than 3.7 GBq/t [0.1 Ci/t] of alpha activity after 300 years).
Category B: wastes of weak and medium activity containing long-lived emitters, mainly alpha emitters, in large quantity (more than 3.7 GBq/t [0.1 Ci/t] of alpha activity, less than 370 GBq/t of beta gamma activity).
Category C: high-activity wastes containing large quantities of fission products, activation products, and actinides. They often generate considerable thermal energy. They are chiefly vitrified wastes. Unreprocessed irradiated fuel is also considered a high-activity waste (without upper limit) [CNE 95].
In France Category A wastes are designed to be stored at a surface site. Andra manages two sites: the Centre de stockage de la Manche (La Manche Center, CSM), which is saturated, and the Centre de stockage de l’Aube (CSA), which is currently receiving waste.
The life of each center consists of three phases:
--exploitation, during which the wastes are stored;
--surveillance, during which the radioactivity of the wastes of short- or medium-period decreases, under surveillance;
--“banalisation,” during which the land can be used “normally without restrictions of a radiological nature” [JO 6.ix.89].
As of early 1999, Andra is seeking authorization for the CSM to enter the surveillance phase.
The fundamental safety rule (RFS) no. I.2 of 19 June 1984 defines “the safety objectives and the design bases for the surface centers intended for the long-term storage” of category A wastes. According to this rule, “the medium-mass activity in alpha emitters for all waste packages [....], calculated at the end of the surveillance phase proposed by the operator [300 years in the case of the CSA and CSM disposal sites] must not exceed 370 MBq per ton [0.01 Ci/t]. Moreover, the maximum mass activity in alpha emitters for each package of waste [...] should as a general rule remain less than 3.7 GBq per ton [0.01 Ci/t] without in any case exceeding 18.5 GBq per ton [0.5 Ci/t].
Category B and C wastes are placed in storage awaiting geological disposal [CNE 95]. They are found at the sites where they were created or at several storage centers, particularly an installation at Cadarache for alpha wastes.
Law 91-1381 December 30, 1991, authorizes “the study of reversible or irreversible disposal possibilities in deep underground geological formations, in particular by means of underground laboratories.” In mid-1996 Andra submitted to the DSIN a request for authorization to construct and operate three laboratories-in the Gard (a granite site) and the Vienne and Haute-Marne/Meuse (clay sites) respectively. In December 1998, the government announced the choice of a clay site at Bure (Meuse) and elimination of candidate sites at Bagnols-sur-Cèze (Gard) and La Chapelle-Baton (Vienne). It affirmed the need for two sites, however, and asked Andra to begin a search for another granite site. The government also indicated that it was insisting on a “logic of reversibility” for the deep-underground site [Reuters 10.xiii.98].
** Andra subsequently drew up a list of fifteen possible granite sites for a laboratory, all in the west of France: le Finistère (Huelgoat canton), les Cotes d’Armor (Plouaret, Quintin, Dinan cantons), l’Orne (Athis canton), la Mayenne (Izé canton), la Vienne (St Barbant Port-de-Salle canton), la Haute Vienne (Auriat canton), la Creuse (Crocq-Sernöel canton), la Corrèze (canton de St Julien Le Vendornois), le Cantal (Glénat canton), l’Aveyron (Sanvensa canton), la Dordogne (Piegut-Pluviers canton), la Vendée (Avrillé canton), les Deux-Sévres (Neuvy-Boin canton). The government appointed a committee of three specialists to enter into dialogue with officials and residents at the candidate locations. However, opposition has been strong, and as of mid July the search has been suspended [NucF 10.vii.2000].
At the end of 2006 or earlier, the government is to send to Parliament a bill authorizing the creation of a storage center for wastes of high activity and long life [JO 1.i.92]. Logically, one of the laboratories will be chosen. The CNE wrote, before the suspension of the search for a granite site, that “if the calendar is respected, Andra should be ready in 2006 to furnish a substantial dossier on the possibilities of storage in a clay medium.” However, as regards granite, Andra risks having to present a dossier based essentially on generic work in which it has participated in foreign laboratories [CNE 00].
WASTE SAID TO BE OF VERY LOW RADIOACTIVITY
The situation is problematic for substances with less than 100 Bq/g of radioactivity for artificial radionuclides or 500 Bq/g for natural radionuclides (called waste of very low activity, TFA). As of mid-2000, French regulations “do not impose on their holders any special obligations in terms of radioprotection” [RGN xi-xii.95]. No storage site for these particular wastes exists, and the wastes are susceptible to circulation in the public domain.
A 1996 Euratom radiation protection directive (96-29) sets thresholds below which material contaminated with radionuclides is exempt from regulation as nuclear material. The directive had a deadline of May 13 for implementation in member nations, which may choose to impose stricter standards. As of August 2000, however, French officials had not completed drafting the radioactive protection decrees that would implement the European regulations in France, and the French regulations are not expected to be published until late in 2000 [NucW 17.ii.00]. It was not known at this time whether the regulations will set exemption thresholds.
Meanwhile, DSIN has developed a policy of dividing installations into radioactive and nonradioactive zones as a means of determining what materials should be treated as radioactive waste during dismantling operations. Those from a radioactive zone would be treated as radioactive materials and measured before release. Those from nonradioactive zones would be treated as conventional materials. Decommissioning decrees for Brennilis and for St. Laurent A-1 embody this policy.
Andra is planning to construct a storage site for TFA wastes near the CSA and to put it into operation in 2002 (see under Champagne-Ardennes, Stockage de déchets très faiblement radioactifs).
WASTES WITH RADIUM
Andra is studying a specific design for a disposal site dedicated to wastes with radium. These “very low activity” wastes contain a notable quantity of radium (a long-lived radionuclide) and give off radon. The majority of these wastes were produced by Rhone-Poulenc in treating rare earths [DSIN 99].
WASTES WITH TRITIUM
At the request of the minister of industry, the High Commissioner of Atomic Energy and the director of DSIN created a working group bringing together Andra and the other entities concerned with wastes with tritium. In 1997 the group dew up an inventory of these wastes and studied management options. In 1999 the group examined the option of a surface disposal site devoted to these wastes [DSIN 99].
WASTES CONTAINING GRAPHITE
The wastes with graphite consist mainly of sleeves and piles of graphite associated with the gas graphite reactors: the G1, G2, and G3 piles at Marcoule; the EDF reactors: Chinon, Bugey, and Saint Laurent-des-Eaux; and the Vandellos-1 reactor in Spain (the fuel from Vandellos was reprocessed at Marcoule and at La Hague). Andra is studying a design for subsurface disposal of these wastes because of their long-lived radionuclides: nickel 63 (half life: 100 years); carbon 14 (half life: 5730 years); and chlorine 36 (half life: 300 000 years) [Rivasi 00]. The working group responsible for this project is the same group that is studying the destiny of tritiated wastes (see above).
DSIN maintains close relationships with the Spanish and British safety authorities in regard to graphite wastes. These three authorities are studying the issue together. Their work should result in a report in 2000 on the future of the graphite wastes [DSIN 99].
The CNE remarks, “The types of waste external to the fuel cycle of EDF’s present reactors pose (…) serious problems (tritiated wastes, graphite, propulsion, etc.). Even if treatment and disposal concepts have been studied, no construction is underway” [CNE 00].
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