According to this govt video about it, the location identified is on the Newry/Dundalk border.
As part of Brexit the UK is leaving Euratom, so this nuclear dump would not be subject to EU norms
"Our work shows that we may find a suitable geological setting for a GDF [geological disposal facility] in a small part of this subregion." gov.uk/guidance/north…
Someone came up with the idea. It was scripted, shot, animated, edited, and then some UK government employee saw it and said 'yes, good, that'll do nicely, upload it to YouTube there and embed it on gov.uk'