Sellafield - the most hazardous building in Britain - is still leaking radioactive water.

The MSSS has been leaking radioactive water into the ground since 2018, releasing enough water to fill an Olympic swimming pool every three years, and is likely to continue leaking until the oldest section of the building has been emptied in the 2050s, around a decade later than previously expected.

Pointing to the fact that Sellafield Ltd had missed most of its annual targets for retrieving waste from buildings, including the MSSS, the committee warned: “The consequence of this underperformance is that the buildings are likely to remain extremely hazardous for longer.”