On the road beyond the limits of recycling

Sarah Nettemann und Janis Leon Pinge

Paper, organic waste, aluminum lids - much of our everyday waste can be recycled. But what happens to legacies of our civilization that are permanently durable and at the same time harmful to the environment? This question was investigated by students and scientists of the Institute of Geosciences during a three-day excursion in February 2020. The focus was on radio- and chemotoxic substances, the effects of which on the environment and landfilling are examined in greater detail in the master's programs in geosciences and biogeosciences.

The program started on 17.02.2020 at the Repository Research Center of the Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) gGmbH in Braunschweig. In addition to a laboratory tour, there was a lecture on topics of site selection, repository research and repository safety. Afterwards, questions could be discussed in a pleasant atmosphere.

Endlager Konrad in Salzgitter
Endlager Konrad in Salzgitter
Image: Prof. Dr. Thorsten Schäfer

With the newly learned knowledge in mind, the next day was a visit to the Konrad repository in Salzgitter, planned for the underground disposal of low and intermediate level radioactive waste. After the necessary safety briefings and changing into clothes specially designed for visitors to the shaft, the group prepared to enter the mine.

In total darkness and at a speed of several meters per second, the participants took the elevator down to the 3rd level of the facility, 1000 meters below ground. In order to be able to reach the sometimes kilometer-long distances between the various starting points underground even at temperatures of up to 35 °C, the group drove through the narrow winding tunnels of the mine in vans specially converted for this purpose. These adventurous journeys were always interrupted by visits to large-scale work measures designed to expand the plant for its future purpose.



In the subsequent Q&A session, even critical questions from hard-nosed geologists were welcome and answered by the staff. On February 19, chemotoxic waste was the topic of discussion. In this context, the underground landfill Herfa-Neurode of K+S KALI GmbH, the largest of its kind worldwide for chemotoxic waste, was visited. The path of the waste from delivery to underground disposal or recycling was traced, with safety precautions and exclusion criteria for the acceptance of waste being discussed. Afterwards, the tour also went underground.

In the corridors, which appear to outsiders to be a huge labyrinth, it was possible to examine landfilling and recycling in operation. All in all, the excursion gave all participants the mostly rare opportunity to get an underground impression of how toxic waste is removed from the biosphere in Germany.

The thematization of these questions and the supervision of corresponding concepts and plants are tasks also for future geoscientists, who should be equipped for this in the best possible way.