INTRODUCTION: This paper will look at EDF’s claim of micro-stability at the Sizewell site – a stability attributed to the protective nature of the offshore Sizewell-Dunwich part-coralline banks. The paper will consider the geomorphology and historical bathymetry of the banks, the effect of climate change, and whether the banks can be relied upon to be sufficiently stable until 2150 (the councils’ date for lifetime to decommissioning and removal of spent fuel). It will also consider the increased stress to the Sizewell foreshore in the face of the banks’ compromise and the subsequent risk to the Sizewell C nuclear complex in particular.