Recommendation 7

We heard from the NDA that the Magnox Swarf Storage Silo is “the most hazardous building in the UK”. It has been leaking radioactive water into the ground since 2018–we calculated, at current rates, enough to fill an Olympic–size swimming pool approximately every three years. The NDA accepted that this leak is its “single biggest environmental issue”. However, the witnesses told us that the radioactive particles are “contained” in the soil and do not pose a risk to the public.9 They also told us that they–and the site’s regulators–believe that the best way of 4 C&AG’s report, paras 13, 3.17, Figure 8 5 C&AG’s report, paras 1, 16, 3.7 6 C&AG’s report, Figure 7 7 Committee of Public Accounts, Nuclear Decommissioning Authority: risk reduction at Sellafield, Sixty–Fifth Report of session 2017 –2019, HC 1375, 31 October 2018 8 C&AG’s report, Figure 8 9 Qq 52–55 9 addressing the leak is to focus on emptying the silo.10 Sellafield Ltd expects that the silo will largely be emptied at some point between 2054 and 2059, which is 8–13 years later than it expected in 2018.11