The Bunker of Burrowout by roscob

You are in a cold, dimly lit room. The room is undecorated and the only furnishing is a small wooden table, which is bolted to the floor. There is a heavy metal door to the West that appears to be locked. You can hear a dripping sound but it is not clear where it is coming from.

To the east is the opening to what appears to be a tunnel.

How and when did you end up here?

Can you work it out and complete your mission?