The container is after coming in and following the corridor. It's in the gut pile.
The container is close to the bulldozer with the turning light.
The container is inside the container next to the bulldozer. Shoot the pink lock to get inside.
Continue the on the path until you get to the bridge that connects two big buildings.
There is a ladder you can climb down to get to a small room where Storage 4 is.
Storage 5, 6 and the Ark Chest:
After defeating Lug the Nut, take the elevator up. All 3 chests are up in a room.