Monte Carlo integrated approach to radiological characterization for nuclear facilities decommissioning

In the last decades, hundreds of nuclear reactors have been shut-down and have experienced decommissioning. This is also the case of L-54M Politecnico di Milano nuclear research reactor. Since shut-down in 1979, the plant has been managed following deferred dismantling strategy. Recently, preliminary radiological characterizations have been launched, even though a more extended campaign is necessary to implement facility decommissioning and restore unrestricted reuse status.In the framework of the IAEA collaborative research project on irradiated GRAphite Processing Approaches, a general radiochemistry and Monte Carlo integrated approach has been developed to study materials activation and support radiological characterization campaign. This integrated method, thanks to its general principles, could be applied to any nuclear reactor or facility undergoing decommissioning, thus helping to reduce the characterization efforts and, possibly, the associated costs.