When waste becomes a resource: Applying a circular economy framework to nuclear power decommissioning

The term “circular economy” (CE) has been used inconsistently in nuclear decommissioning, leading to potential misinterpretations and mismatches between CE definitions and practices. With numerous nuclear installations worldwide requiring decommissioning, a clear and consolidated definition of CE, along with relevant dimensions and indicators, is needed to enable transition from the prevailing linear approach to a more sustainable and circular one. This study addresses two key questions: How can CE be defined in the context of nuclear decommissioning to ensure clarity and consistency? What key indicators can assess the practical implementation of CE in decommissioning? A two-round Delphi study was conducted in 2024 with nine experts to address these questions. The findings were validated through a facilitated Group discussion with 19 stakeholders, including industry professionals, operators, authorities, and researchers. The results provide a unified definition of CE in nuclear decommissioning and measurable indicators covering societal, environmental, health and safety, techno-economic, and legal dimensions. This study offers actionable insights for regulators, practitioners and policymakers, facilitating the integration CE principles and the comprehensive evaluation of circularity in nuclear decommissioning processes. • Nearly half of 423 nuclear reactors may begin decommissioning by 2050, taking decades. • Through waste reduction and resource reuse, the Circular Economy supports global sustainability goals. • The term ‘circular economy’ is often used inconsistently, leading to confusion and misuse. • A consolidated definition of Circular Economy, key concepts, dimensions and indicators are developed. • Societal, environmental, safety, economic, and legal dimensions indicators are defined.