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Step 4

Step 4 commenced on 13 February and is an in-depth assessment of the safety case evidence, security case evidence and the generic site envelope, on a sampling basis.

The aim of this step is to:

  • confirm that the higher-level claims and arguments are properly justified;
  • progress the resolution of issues identified during Step 3;
  • complete sufficient detailed assessment to allow ONR to decide whether a DAC can be issued.

We published the following documents at the start of Step 4:

As part of the GDA process, the public is invited to review and comment on the documents, which can be accessed via the links above.

Some documents may contain commercially sensitive, export-controlled or sensitive nuclear information and so, in line with GDA guidance, we have made judgements on areas to be redacted prior to being made public.

Should you wish to comment on these documents, please use our Comment page or send your comments to our Freepost address on the Contact us page.