They should have took the stacks down. I bet we find out that the stacks collapsed on the building.
also from the pictures I am seeing there was a lot of decay on the buildings (mortar and bricks) and they left it that way to give the place that old feeling.
Many years ago we had a old 5+ story factory (Welch Baby Carriage Factory) in St. Louis that had a full wall collapse (all 5+ stories). Instead of tearing the building down they rebuilt the wall and turned it into lofts. There is no way I would ever live there.