Though the structure is not currently served by rail, the tracks of the North Shore Scenic Railroad pass the building and there is at least one siding to the building. In the past coal would have been delivered there and fly ash would have been shipped out. The fly ash is a by product of the burned coal and is used in the making of cement. There is quite a demand for it. These days the fly ash would be shipped out by truck but the fly ash hopper (the cream coloured thing to the right of the second picture) is directly over the railroad tracks. So there is plenty of justification for having such a rail served industry on this small layout.
I'm sorry that these pictures are so small but for some reason I have lost the originals. I pilfered these from a plan I supplied to Carl Arendts micro layout gallery. I guess that means another trip up to Duluth for research purposes That will not be a hardship...