Preprint – Final version see: Lits G. (2020) “The European Governance of Radioactive Waste: A Story of Stakeholder’s Involvement”. In: Orsini A., Kavvatha E., EU Environmental Governance: Current and Future Challenges. pp. 79-99. 1 The European Governance of Radioactive Waste: A Story of Stakeholder’s Involvement Grégoire Lits Université catholique de Louvain, Institut langage et communication. Abstract In most European countries, Nuclear Waste Management (NWM) became a subject of concern for public authorities with the development of the nuclear power industry in the 1970s. If NWM is still a national prerogative, it is also true that it has been, since its inception, conceived as an object of global and European governance. International organisations such as the Euratom, the IAEA or the OECD have played a pivotal role in the development of the industry and in setting up international safety standards. This was reinforced in 2011 when the EU adopted a legally binding directive known as the “waste directive” (Directive Euratom/2011/70) that “establish a community framework for the responsible and safe management of spent fuel and radioactive waste”. This chapter will present the main characteristic of the European nuclear waste governance system. A first section will be devoted to some technical considerations about how radioactive waste have historically been dealt with in the EU. The second section will focus on the different regulatory initiatives that have taken place since the inception of a European nuclear governance. A concluding section will present some current challenges for NWM governance in the EU especially regarding stakeholders’ participation and public involvement in NWM decision-making processes. Introduction Radioactive waste (also known as nuclear waste) have been generated since the advent of the nuclear industry with the commissioning of the Shinkolobwe uranium mine in Belgian Congo in 1921. Since then, nuclear technologies have spanned across a wide array of sectors. Applications are found in medical, research or food processing industries, but also in strategic sectors such as the military or energy industry. Having different origins, radioactive waste can be very different types of substances and involve different levels or types of radiation. Their only common traits being that (i) they contain radioactivity at a level considered harmful for the environment or for public health and (ii) they are not considered useful. These characteristics are reflected in the most general definition of a radioactive waste given by the International Atomic Energy Agency (IAEA) in his Radioactive Waste Management Glossary, i.e.: [a] “Material in gaseous, liquid or solid form for which no further use is foreseen” (IAEA 2003: 46). As radioactivity naturally decreases with time, most nuclear waste can be managed by isolating them from the environment for a certain period of time. This makes them different from other hazardous industrial or chemical waste, and triggered the need for a dedicated management strategy. In most European countries, Nuclear Waste Management (NWM) became a subject of concern for public authorities with the development of the nuclear power industry and the construction of the first nuclear reactors and nuclear power plants (NPP) between 1956 (first commercial NPP in the world made critical [able to operate in normal condition] in UK) and 1975. Since 1975, the majority of waste come from the production of electricity in NPPs and NWM has been recognized as a national