They don’t. The USCG uses consultants from within the inustry-to do otherwise would be stupid. Professional petroleum engineers, geologists and technicians are doing the work, the government is simply giving advise and consent (with emphasis on the latter) to the process, filtered through the political expediance litmus of course.
In Iraq in early 2003, US Army Corps of Eng Task Force RIO (Restore Iraqi Oil) used similar teams (alongside Iraqi oil crews) to make safe, shut down, test and restart the oil facilities throughout Iraq. Oil began flowing to VLCC (very large crude carriers) Tankers on/about 23 June from the off shore terminal in the Persian Gulf; earlier than that oil was flowing through the Northern pipeline to terminals in Turkey. Banking dollars for the new Iraq.
Success story compared to this political debacle.
Best;
Sorry. I misplaced my sarcasm off symbol. Having worked in the oil industry I’m reasonably familiar with whose actually doing the work.