In our contribution, we present the key results of the stakeholder workshop Nuclear Waste Disposal – Possible Paths, Directional Decisions, Future Challenges. In the decade-long process of site selection and final storage, it is highly probable that unforeseen developments will occur and that a response will be needed. We focus on the problems and perceptions of the participants and to what extent the experimental setting of the workshop is suitable for promoting collective problem-solving.

Using case examples, insights and experiences from a complex conceptualisation and application process and two years research experience in the TRANSENS project will be presented taking the views of the involved (standing Working Group Population and scientists). Particularly, the understanding of transdisciplinarity will be discussed given the varying definitions in literature.

For specialists, the tool Safety Case (in the German site selection procedure: Sicherheitsuntersuchung) is an established instrument for supporting safety-relevant decisions in a stepwise disposal programme. Actors, affected individuals and interested persons have different notions and value judgements about it, though. In the TRANSENS project, it is planned to reveal these notions and judgements and, if possible, to derive conclusions about optimising the safety case concept.