Sheila Jasanoff conceptualized civic epistemologies as stable, socio-institutional forms of vetting, producing, and using policy-relevant knowledge that persist in particular political cultures. STS studies of credibility struggles are premised upon shared epistemological and moral foundations, even as they carefully remove markers of the all-too-human arbitration process. But how should one view credibility struggles in times of geological upheaval, where epistemological and political substrates are being torn apart and reconfigured? How should we conceptualize democratic legitimacy during periods of technological intrusions? Using the case of anti-nuclear activism in India, I demonstrate how activists, villagers, and different state officials are engaged in tectonic credibility struggles. Such contestations are overtly political and epistemic, and attempt to instantiate particular nuclear-democratic imaginaries by forming and expanding credibility economies across different audiences. The substantial challenges activists face in forming networked credibility economies necessitate re-theorizing civic epistemologies in India and beyond.