iMAGINE – or why we need to know what influence new technologies can have on the final disposal

The way to a final disposal for highly-active waste and the disposal strategy has been laid down in the Standortauswahlgesetz (StandAG) and the Standortauswahlverfahren (StandAV). The core focus has been put on a deep geological disposal for the heat producing waste. However, the mandate from the StandAG is also to examine whether alternative disposal routes could make a positive contribution to the task. Previously, Germany invested heavily in deep geological disposal by concentrating research and development on what seemed to be the in-time choice. However, the decision to delay the site selection process must now be used prudently by examining alternative innovative technologies which could make a positive contribution to final disposal. The delay, coupled with the emergence of novel technologies like iMAGINE - which promise to completely avoid the need for the deep geological disposal for heat producing waste - opens a unique, unmissable opportunity. These new, advanced technologies have the potentially a much stronger influence on the process as well as the final outcome than what has been expected for advanced reactors.

In the wider context, as a society, Germany needs to know how to best solve the waste handling/storage problem; to do this, we need to understand if the very promising, recently published scientific results can be demonstrated to deliver in the real-world.

Due to significant investmentsof the past, modern simulation technologies in nuclear have a very high standard and level of quality assurance for conventional reactors. Even for unknown systems, IAEA gives a trusted standard of ± 10%. But we have to keep in mind, there is a difference between the real-world and the related computer model, which is an approximate abstract representation of the problem. Especially for highly innovative systems like Molten Salt Reactors, there are no specifically developed and validated codes yet. Thus, what we simulate can be a high-quality representation of a maybe incomplete system since we may not be aware of all the relevant phenomena.

The conclusion of this can only be: we need to demonstrate promising new technologies and then evaluate them against the existing solution, deep geological disposal, to understand the potential opportunities.

Only with this acquired understanding can we assure that the required future political decision on the handling of nuclear waste is fact-based, while without this, we can only decide on perception, identity, and/or ideology. Thus, as socially responsible scientists, our aim must be to create the facts on highly society-relevant problems and support political decision making based on scientific evidence-base. As highlighted by Krogsgaard-Larsen et al. in 2011, social responsibility is the "responsibility of scientists of all disciplines to direct their research activities in such a way that they can contribute to the well-being of society and to meeting the challenges of our time".

To support the understanding and to facilitate a scientific discussion a short overview on the key opportunities and technical challenges, as well as a development plan for iMAGINE will be given.