Excellent question Peter,
From my data management focused perspective, a key technical base line is good quality well engineering records throughout the entire well life cycle.
Some UK NS wells are 40 to 50 years old, so access to legacy well engineering data can be a challenge.
I understand that the key documents for the full well engineering life cycle are (I think) described in the The Guidelines for Decommissioning of Wells, as issued by Oil & Gas UK, Version 6.
full well engineering life cycle documents (ideally digitally enabled, e.g.
with OCR) as a key deliverable will enable:
(i) good after action review (AAR) and lessons learned processes
... and ...
(ii) data driven analysis, data analytics and future (re)intepretation, in the age of digital well data and information capture.