The search for a final nuclear repository in Germany poses a societal and political issue of high national medial presence and controversy. The German Repository Site Selection Act demands the search to be a “participatory, science-based [...] process”. Also, the repository search combines numerous scientific aspects (e. g., geological analyses, technical requirements) with broad societal implications. For these reasons it constitutes a promising background to analyze the general public’s habits regarding referencing research on Twitter. We collected tweets associated with the conversation around the German nuclear repository search based on keywords. Subsamples of the resulting tweet set are coded regarding sending users’ professional roles and types of hyperlinked content. We found the most vocal group participating in the conversation to be activists and initiatives, while journalists constituted the follower-wise most influential accounts in the sample. Regarding references to scientific content, we found only very few cases of direct links to scholarly publications; however, several kinds of indirect references to academic findings could be identified, e. g., links to paraphrases of studies in news articles or blog posts. Our results indicate participation from a fairly diverse set of users in the observed communication around the German repository search; exchanges of research findings however appear to have happened rarely and been limited to very few particular studies. The findings also illustrate a central problem regarding the expressive power of socialmedia-based altmetrics, namely that a large share of signals indicating a scholar-y work’s influence will not be found by searching for explicit identifiers.