LOCATION
In the reactor maintenance tunnel that you swim through from the auxiliary coolant tank to the main reactor.
[setpos -1157.307495 -95.198456 -887.755737;setang 21.191437 44.517006 -0.618001]
DETAILS
I was swimming through the reactor maintenance tunnel pressing against the top left of the tunnel. After the loading screen I was stuck there unable to move until I drowned. This continued on auto-load as well. Luckily I had a manual save beforehand.
SCREENSHOT
NOTE: This bug is easily reproducible.