Maximus: Go to the 2nd big level of the Abandoned mines. This is the one when you get off the elevator, you stand at a 4-way intersection.
Go left. Find the first room on your left. It's got a lot of tombstones in it, a chest, and a broken cart. Right next to the broken cart is an iron rod that most people miss.
It's the trolley lever.
Hope this helps!
-Sazerac