Options for marking a geological repository

The safe disposal of high-level radioactive waste is a complex technical, social, and communicative task. A key question is how geological repositories can be marked over tens of thousands of years in such a way that future generations are effectively warned of the dangers and knowledge about the location, purpose, and risks is preserved. This challenge touches on scientific, technical, semiotic, legal, and sociocultural dimensions. Despite intensive international research, key questions remain unanswered: Which materials and designs are stable over geological time scales? How can comprehensibility be ensured despite cultural change? And how can marking systems be combined effectively with other forms of knowledge preservation? BOKU's contribution to the project lies in particular in the analysis of possible scenarios of human intrusion into repositories and in the systematic comparison and evaluation of different types of marking.