The presence of uranium in grouted Magnox intermediate level waste (ILW) containers is a concern for the nuclear waste industry. Recent inspection of 16 randomly selected ILW containers revealed bulging around the circumference of 3 containers, the cause of which is currently unknown. The bulges are suspected to be related to the intermittent existence of large uranium masses, the corrosion of which produces products almost twice the volume of uranium metal. Formation of hydrogen and uranium hydride through the oxidation of uranium and Magnox with water is of particular concern owing to their pyrophoric nature on exposure to oxidising conditions should the container fail. The understanding of uranium corrosion mechanisms and rates in ILW containment is therefore vital in assessing the risk posed by the bulging waste containers during container storage, transportation and disposal. The following study aimed to contribute to this understanding by performing experiments that transition from laboratory based investigations to conditions more relevant to real ILW scenarios.