Abstracts ASN Report 2019

LA HAGUE SITE The Orano site at La Hague is located on the north-west tip of the Cotentin peninsula, in the Manche département ً א ׎ ژ Ǹȅ ɯƺɀɎ Ȓǔ !ǝƺȸƫȒɖȸǕ ƏȇƳ ژה Ǹȅ ǔȸȒȅ !Əȵ Ƴƺ nƏ RƏǕɖƺِ Áǝǣɀ ɀǣɎƺ is situated about fifteen kilometres from the Channel Islands. LA HAGUE ORANO CYCLE REPROCESSING PLANTS IN OPERATION The La Hague plants for reprocessing fuel assemblies irrad- iated in the nuclear reactors are operated by Orano Cycle La Hague. Áǝƺ ɮƏȸǣȒɖɀ ǔƏƬǣǼǣɎǣƺɀ Ȓǔ Ɏǝƺ Ȩ ٮב ٢ zX ژ ׏׏ ה ٣ ƏȇƳ Ȩ זٮא ׎׎ ٢ zX ژ ׏׏ ו ٣ ȵǼƏȇɎɀ ƏȇƳ Ȓǔ Ɏǝƺ ³Á0 ژב ٢ zX ژ ׏׏ ז ٣ 0ǔǔǼɖƺȇɎ ÁȸƺƏɎȅƺȇɎ ³ɎƏɎǣȒȇ ɯƺȸƺ ƬȒȅȅǣɀɀǣȒȇƺƳ ǔȸȒȅ ׏ ژהזח ٢ȸƺƬƺȵɎǣȒȇ ƏȇƳ ɀɎȒȸƏǕƺ Ȓǔ ɀȵƺȇɎ ǔɖƺǼ ƏɀɀƺȅƫǼǣƺɀ٣ ɎȒ א ׎׎ ژא ٢« ژג ȵǼɖɎȒȇǣɖȅ reprocessing facility), with most of the process facilities entering service in 1989-1990. Áǝƺ (ƺƬȸƺƺɀ Ȓǔ ׏׎ ژ hƏȇɖƏȸɵ א ׎׎ ژב ɀƺɎ Ɏǝƺ ǣȇƳǣɮǣƳɖƏǼ ȸƺȵȸȒƬƺɀɀ ٮ ǣȇǕ ƬƏȵƏƬǣɎɵ Ȓǔ ƺƏƬǝ Ȓǔ Ɏǝƺ ɎɯȒ ȵǼƏȇɎɀ ƏɎ ׏ً׎׎׎ ژ ɎȒȇȇƺɀ ȵƺȸ year, in terms of the quantities of uranium and plutonium contained in the fuel assemblies before burn-up (in the ȸƺƏƬɎȒȸ٣ً ƏȇƳ ǼǣȅǣɎ Ɏǝƺ ɎȒɎƏǼ ƬƏȵƏƬǣɎɵ Ȓǔ Ɏǝƺ ɎɯȒ ژ ȵǼƏȇɎɀ ɎȒ ׏ً ו ׎׎ ژ ɎȒȇȇƺɀ ȵƺȸ ɵƺƏȸِ Áǝƺ ǼǣȅǣɎɀ ƏȇƳ ƬȒȇƳǣɎǣȒȇɀ ǔȒȸ ƳǣɀƬǝƏȸǕƺɀ and water intake by the site are defined by ASN resolutions א ׎׏ ٮ!(ٮד ׎ ژדבד ƏȇƳ א ׎׏ ٮ!(ٮד ׎ הבד Ȓǔ (ژאא ƺƬƺȅƫƺȸ אژ ׎׏ ד ِ Operations carried out in the plants The reprocessing plants comprise several industrial units, each intended for a particular operation. Consequently there are facilities for the reception and storage of spent fuel assemblies, for their shearing and dissolution, for the chemical separation of fission products, uranium and plutonium, for the purification of uranium and plutonium, for treating the effluents and for packaging the waste. When the spent fuel assemblies arrive at the plants in their transport packaging, they are unloaded either “under water” in a pool, or dry in a sealed shielded cell. The fuel assemblies are first stored in pools to cool them down. The fuel assemblies are then sheared and dissolved in nitric acid to separate the fragments of metal cladding from the spent nuclear fuel. The fragments of cladding, insoluble in nitric acid, are removed from the dissolver, rinsed in acid and then water, and transferred to a compacting and packaging unit. The nitric acid solution containing the dissolved radioactive substances is then processed to extract the uranium and plutonium from it, leaving the fission products and the other transuranium elements. After purification, the uranium is concentrated and stored as uranyl nitrate UO 2 (NO 3 ) 2 . It will then be converted into a solid compound (U 3 O 8 ) called “reprocessed uranium” in the ÁÈ ژד ǔƏƬǣǼǣɎɵ Ȓȇ Ɏǝƺ ÁȸǣƬƏɀɎǣȇ ɀǣɎƺِ After purification and concentration, the plutonium is precipitated by oxalic acid, dried, calcined into plutoniumoxide, packaged in sealed containers and stored. The plutonium is then used for the fabrication of MOX fuels in the Orano Cycle plant (Melox) on the Marcoule site. The effluents and waste produced by the operation of the plants The fission products and other transuranium elements resulting from reprocessing are concentrated, vitrified and packaged in standard vitrified waste packages (CSD-V). The fragments of metal cladding are compacted and packaged in standard compacted waste packages (CSD-C). Furthermore, the reprocessing operations described in the previous paragraph involve chemical and mechanical processes which produce gaseous and liquid effluents and solid waste. The solid waste is packaged on site by either compaction or encapsulation in cement. The solid radioactive waste resulting from the reprocessing of the spent fuel assemblies from the French reactors is, depending on its composition, either sent to the Aube repository (CSA) or stored on the Orano Cycle La Hague site until a definitive disposal solution is found (particularly the CSD-V et CSD-C packages). Xȇ ƏƬƬȒȸƳƏȇƬƺ ɯǣɎǝ ȸɎǣƬǼƺ nِ ژאٮאגד Ȓǔ Ɏǝƺ 0ȇɮǣȸȒȇȅƺȇɎ !ȒƳƺً the radioactive waste resulting from the reprocessing of spent fuel assemblies originating from foreign countries is sent back to the owners. However, it is impossible to physically separate the waste according to the fuels from which it originates. In order to guarantee an equitable distribution of the waste resulting from the reprocessing of the fuels of its various customers, the licensee has proposed an accounting system that tracks the entries into and exits from the La Hague plant. This system, called Exper system, was approved by the Order Ȓǔ …ژא ƬɎȒƫƺȸ א ׎׎ ژז Ȓǔ Ɏǝƺ xǣȇǣɀɎƺȸ ȸƺɀȵȒȇɀǣƫǼƺ ǔȒȸ ƺȇƺȸǕɵِ The gaseous effluents are released mainly when the fuel assemblies are sheared and during the dissolution process. These gaseous effluents are treated by washing in a gas treatment unit. The residual radioactive gases, particularly krypton and tritium, are checked before being discharged into the atmosphere. The liquid effluents are treated and generally recycled. Some radionuclides, such as iodine and tritium, are channelled –after being checked– to the sea discharge outfall. This outfall, like the other outfalls of the site, is subject to discharge limits. The other effluents are routed to the site’s packaging units (solid glass or bitumen matrix). ASN Report on the state of nuclear safety and radiation protection in France in 2019 73 REGIONAL OVERVIEWOF NUCLEAR SAFETY AND RADIATION PROTECTION NORMANDIE