All those are within the Armoury, which is tricky to get into. The door is at bottom of the offices but the switch to open it (can't be lockpicked) is two stories above and you can either jump up there (very difficult) or go back into the Depot and find the door to the top floor.
Once inside the Armoury, the Keller refuge (the bunker) can only be opened if you've found codes, there's four scattered around the wasteland I think.