are high. These operations must be based on characterisation of the waste and qualification of the processes envisaged, for which the licensee must reinforce its methods to confirm the feasibility of the envisaged solutions. The WRC* worksites are of particular importance, given the inventory of radioactive substances present and the age of the facilities in which they are stored, which do not meet current safety standards. WRC* projects are becoming increasingly complex owing to the interactions with the plants in operation on the site. Some work could span a period of several decades. In addition, Orano does not systematically envisage demolishing the structure of the facilities: some of them will continue to be used for industrial purposes (equipment storage, etc.). In order to achieve the target final state, clean-out of the structures and soils is Orano’s reference option. However, the licensee does not rule out a two-stage operation, in order to meet the need for temporary use of all or part of the facility. The decommissioning and WRC* operations will generate a large quantity of waste, for which there is no disposal route. When disposal routes are not yet available, the management solution adopted by Orano is interim storage. In order to deal with a high level of industrial complexity, a strategy which envisages reusing certain structures ASN’S POSITION In 2016, Orano transmitted its decommissioning and waste management strategy for the La Hague and Tricastin sites. After reviewing these aspects, which led to a cycle of discussions with Orano, ASN notes progress in the assimilation of the immediate dismantling objectives, progress in the decommissioning operations on several facilities at Tricastin and the definition of conditioning processes for radioactive waste from the La Hague site. ASN nonetheless asked it to improve the following four aspects of its strategy: • decommissioning and waste management must be prioritised according to the risks and Orano must design new reprocessing, conditioning, storage and transport capacity for effluents and waste, in order to replace certain ageing equipment and increase storage capacity; • implementation of the clean-out strategy must be based on sufficient knowledge of the current state of the facilities and more particularly the civil engineering structures and soils. It also ensures that clean-out is taken as far as reasonably achievable if complete clean-out is not possible for technical or economic reasons; • WRC* must be better managed: the issue is to characterise the waste and qualify processes so that it can be retrieved and conditioned in order to reduce the risks from its radioactivity as early as possible; • the oversight of complex projects* must be improved: Orano must analyse the causes of delays to the priority projects and ensure the adequacy of the resources devoted to these projects so that it can submit detailed 5-year activity schedules to ASN, presenting the key milestones. * See glossary page 30 In the future, Orano will have to conduct several large-scale decommissioning projects: that of the first generation fuel reprocessing plant at La Hague (UP2-400 and its support units), as well as that of the uranium conversion* and enrichment* plants at Tricastin. The licensee adopts the principle of immediate dismantling; it must carry out certain particularly complex operations, notably those linked to WRC*, for which the safety and radiation protection stakes For more information, scan this QR code. 14 • Les cahiers de l’ASN • June 2022 BNIs BEING DECOMMISSIONED
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