RHONE-ALPES

Purpose/type: fuel fabrication plants

Installations: Cerca plant-fuel for research reactors; FBFC plant: Société franco-belge de fabrication de combustibles-fuel for pressurized water reactors

Operators: Cerca and FBFC .  Both Cerca and FBFC have become subsidiaries of Areva NP

Period of operation: since 1962 (entry into service Cerca 1962; FBFC 1977)

Raw materials: uranium at all levels of enrichment (Cerca); low-enriched uranium hexafluoride (FBFC)

Beginning with the construction of the FBFC plant at Romans, FBFC has employed the personnel of Cerca-Romans. The two plants at Romans share several laboratories, stores, and general services.

Cerca participataed in the development and production of fuel for gas graphite reactors (UNGG), light water reactors, fast neutron reactors, and high temperature reactors. The plant has, however, specialized in "laminated" fuel (in the form of plates). Cerca is authorized to work with uranium enriched to 93.5% uranium 235 [DSIN 98]. The plant has furnished all the uranium/aluminum fuel with 93% uranium 235 for French research reactors, and has sold this fuel abroad. It also produced and may still produce uranium/aluminum-aluminum fuel for the Célestin reactors. Fuel fabrication takes place in the F2 shop.

In 1995 Cerca and the American company General Atomics created a subsidiary in common, Triga International, responsible for commercializing the fuel designed for Triga research reactors sold by General Atomics. Cerca created, at Romans, in building F2, a shop for the production of Triga fuel, a metallic fuel with a base of uranium and zirconium hydrides [Ener 27.vii.95]. The uranium in fuel of the Triga type is normally enriched to 20% uranium 235. October 30, 1996, DSIN authorized the entry into service of the Triga shop, with uranium enriched to up to 20% uranium 235; and, May 14, 1997 authorized the first shipments of this fuel [Con ii.97 et Con i.00]. The shop includes a furnace for hydridation [Con xii.96].

On several occasions, DSIN has authorized Cerca to carry out production campaigns using lots "of uranium enriched to 20% in isotope 235, the composition of which, in regard to other isotopes, is slightly superior to the specification for uranium described in the safety report for the workshop" for laminated fuel.  August 7, 2000, the ministers responsible for the environment and for industry gave a generic authorization for the use of contaminated "commercial" uranium.  The authorization concerns, at least in part, "uranium from the dismantling of nuclear weapons" [DSIN 00; Con xi.00].

Although Cerca still produces fuel with highly enriched uranium, the plant plays an important role in the international RERTR (Reduced Enrichment Research and Test Reactor) program, designed to create and to fabricate fuel enriched to less than 20% uranium 235. It produces a silicide fuel, U3Si2-Al with 19.75% uranium 235, and is today developing a uranium-molybdenum fuel with an enrichment inferior to 20% and with a density of less than 8 g of uranium/cm3 [NucF iv.3.00].   The pilot installation Télémaque produces a powder that is a uranium-molybdenum alloy [Con i.04].  

For the production of research reactor fuel, Cerca manipulated annually, around 1993, several dozen kilos of highly enriched uranium and several hundred kilos of low-enriched uranium [NucF x.25.93].

Cerca owns a department of mechanical equipment. Moreover, Cerca studied and handled depleted uranium for civilian and military purposes. The plant "was a part of the Dam’s depleted uranium production and residues circuits" until the beginning of the nineties [Ambolet 88; also see Bonneuil-Cerca].

In 1991 Cerca proposed to its clients the conversion of uranium hexafluoride (UF6) at all levels of enrichment into uranium metal, also the recovery of uranium in residues at all enrichment levels [NucF 4.iii.91].

In 1994 and 1995 Cerca managed a stock of highly enriched uranium of American origin. Cerca stored the highly enriched uranium on behalf of other European institutions that formerly used this type of uranium [NucF 23.v.94 and 6.xi.95]. It is probable that this stock still exists.

In March 2005, Cerca requested authorization to operate a pilot unit for manufacturing High Temperature Reactor (HTR) fuel.  The unit would be part of a research and development program for Generation IV reactors [ASN 05].

LIQUID EFFLUENTS

Apparently the liquid effluents are treated today in the new Neptune installation (see below).

REJECTS AND SOLID WASTES

In 1991 the DSIN authorized "the operation of a recycling unit for rejected plates and kernels of enriched uranium." In a Workshop for Recycling Plates in Building F2, the recycling method includes two attacks with sodium hydroxide, the first to eliminate the remains of the cladding and the second to dissolve the uranium matrix at the core of the plates; the recovery on filters of the uranium powder; and the drying of that powder. Cerca planned to recover 375 kg of uranium enriched to less than 20% and 36 kg of uranium enriched to 93.5% per year [FBFC 97].

An "Atelier de prétraitement" in MA2 recovers uranium 235 from byproducts. The procedure includes the attack with sodium hydroxide, the filtration of the obtained solutions, the calcination of the precipitate to transform it into U308, and the packaging. The U3O8 is sent "to a specialized treatment center to transform it into reusable uranium metal." It is possible that the treatment center is the Usine de traitement de l’uranium enrichi (URE) belonging to Cogéma at Tricastin. Around 1997, the workshop handled about 279 kg of uranium at less than 20% enrichment and 331 kg at less than 93.5% enrichment [FBFC 97].

The metallic wastes intended for Andra are packaged in building AX2 of INB 98 [Con ii.98].

After FBFC ended uranium operations at its Pierrelatte plant, FBFC operated two plants—Romans and Dessel (Belgium). The Romans plant carries out the entire process of fuel fabrication for pressurized water reactors. FBFC sent uranium oxide powder to Dessel for use there, but production ceased at this factory in 2006 and as of 2008 it is being dismantled.  

A complete fabrication chain at Romans is devoted to reprocessed uranium. The chain began operation in 1994 or 1995 and has a capacity of around 200 t/yr of uranium [RGN v-vi.97]. The DSIN authorized the use of uranium from reprocessing (URE), one campaign at a time. August 7, 2000, FBFC received a generic authorization to make fuel with reprocessed uranium [DSIN 00; Con xi.00].

The plant normally receives uranium in the form of crystals of uranium hexafluoride (UF6) which are transformed into powder (for the production of UO2 pellets) through a gaseous step (see Fabrication of Uranium-Based Fuel). In 1998, DSIN authorized FBFC to undertake a campaign to fabricate UO2 pellets from UO3 powder. FBFC was to transform two tons of uranium; and was to carry out the transformation of UO3 into UO2 by calcination and by reduction inside a furnace [Con xii.98].

Decree 2006-329 of 20 March 2006, which raised the annual capacity of the plant to 1800 t for the conversion workshop and 1400 tons for the lines making pastilles, rods, and assemblies, also authorized, on an exceptional basis, the assembly of fuel rods containing plutonium oxide.  The authorization of the ministers responsible for industry and environment is necessary for each such operation.  The uranium that FBFC handles at Romans cannot be enriched above 5%.  

Treatment of Wastes and Rejects

SOLID WASTES

The AX2 installation, located in INB 98, includes a zone for storing production wastes and a decontamination and incineration shop [DSIN 98]. FBFC put into service in 1985 an incinerator for uranium wastes. The incinerator is authorized to handle only uranium enriched to 5% or less, uranium 235. The packaging of metallic wastes is carried out in AX2 [Con ii.98].

The packaging of metal wastes is carried out in AX2 [Con ii.98]. 

A recycling shop carries out "various physical-chemical procedures intended to recover and recycle the uranium contained in the production discards and in the ashes from the incineration of the waste" [Con vi.99].  Andra explained in 1988 that "there were great difficulties in the recovery of uranium. The calcination and incineration cause a chemical transformation of the uranium oxide into a form that is difficult to dissolve" [Compte 88]. However, according to oral testimony, the recovery turned out to be very lucrative.

An oven for grilling equips the second pellet line. "This oven is used to treat thermally the discarded products coming from various shops in the factory (powders, pellets, sludges from rectification) with an eye to their recycling" [Con vi.96].

LIQUID WASTES

Neptune treats the uranium-contaminated liquid effluents from the site. About 1998, the installation AX2 was equipped with a purification station that allows the recovery of uranium contained in uranium-contaminated effluents [DSIN 98]. It is probable that the purification station located in AX2 is the installation that has been named Neptune. The construction of Neptune was the result of an engagement made by FBFC in 1998 at the time of the public inquiry into the renewal of authorizations for the release of effluents [Con iii.00]. We have no information on the treatment methods used by Neptune. In 1993, a decontamination station included a centrifuge for uranium effluents.

AUTHORIZATION FOR RELEASES

A request for a new authorization for liquid and gaseous releases, which integrates chemical releases, was submitted to public inquiry at the beginning of 1998 [Con iv.98; DSIN 98]. A new decree was published in the Journal officiel 28 July.  This authorization takes into account foreseeable developments in the plant (use of reprocessed uranium or contaminated uranium, in particular because of putting on the market nuclear materials from the dismantling of nuclear weapons) [Con xi.00].  

WASTES RELEASED/SENT OUTSIDE THE PLANT

In 1993, when presenting conversion by the dry method, Jean-Luc Lamy, in charge of radioprotection "in several plants for enriched uranium" for thirty years, described the "visit to a major production plant, for making fuel (Vallée du Rhône)": "No continuous atmospheric measure, no immediate alarm (useless). Uranium oxide is everywhere, in small brown patches here and there, and, in the air, pastilles, splashes of UO2 on the ground." He talks also of releases of fluoride to the exterior, when the plant goes (to the end of saturation" of calcium fluoride [Lamy 93b].  

Today, 90% of the gaseous releases from the site come from the incinerator [Con iv.99].

The work of decontamination can be assumed to produce liquid effluents contaminated by alpha emitters and radioactive sludges resulting from the treatment of these liquids. Because of pressure from residents of Romans, the liquid effluents released after "purification" have been sent directly to the Isère since the summer of 2000. They were formerly sent to the city’s treatment system.

FBFC sent to the Chambard (Drôme) dump the calcium fluoride from the treatment of the hydrofluoric acid vapors that are released. The dump was closed in 1991. The plant apparently still produces fluorine. If so, where is it sent?

Andra enumerates various wastes (metallic wastes, bricks, filters, graphite, rubber . . ), awaiting dispatch to Andra, and a stock of 33,000 liters of oil awaiting dispatch to a treatment center. All these wastes are contaminated by uranium 234, 235, and 238 [Andra 99].

The production chain devoted to URE, put into operation in 1994 or 1995, is equipped with supplementary protective measures. To handle reprocessed uranium, it is necessary to increase the tightness of the containers of uranium dioxide powder, because the alpha emitters, and notably the uranium 234, present a risk of contamination. The concentration of uranium 234 in the reprocessed uranium is three to five times higher than in the UO2 of natural uranium [Henckes 94]. The risk of alpha contamination of the gaseous effluents is increased.

The conversion of UF6 into UO2 at the production factory is a partial purification step, because the descendents of uranium 232 remain for the most part in the transport cylinders when the UF6 is vaporized. To protect workers, it is necessary to carry out the manufacture rapidly before the descendents accumulate too much. Six months after conversion of UF6 into UO2, the rate of gamma irradiation, on contact with a fuel assembly, is nine times higher with reprocessed uranium than with natural uranium. The use of biological screens is likewise necessary to protect workers.

According to FBFC, descendents of uranium 232 increase the radioactivity of liquid effluents coming from the chemical recycling workshop and from the incinerator.

The solid wastes must be packaged for long-term storage [Henckes 94].

Selected incidents at FBFC in 2008 and 2009

July 17, 2008 FBFC informed ASN that an underground pipe containing uranium-bearing liquids was ruptured.  FBFC told inspectors from ASN later that day that the rupture could have existed for several years.  FBFC began cleanup on July 18.  See ASN's note (Avis 18.vii.08]. 

FBFC conducted a study of the ground at the site, the results of which it submitted to ASN and made public in October 2009. FBFC had found a slow and progressive accumulation of uranium-bearing sludge in a section of an old pipe carrying rainwater and in the ground under the storm-water basin in the interior of the site.  FBFC reported that there was no risk of a criticality or harm to employees or residents of the area and submitted to ASN a plan for cleaning up the pipe and the basin, which will be put into effect in 2010-2011 [ASNAvis 17.xi.09; DauLib 14.xi.09].

                                                                                                                     -- last entered January 5, 2010

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