I'm very familiar with the concrete company, my dad works in the building next to them, but last had been up there the siding didn't go all the way in like it was supposed to. Maybe they finished it on load from the field? The old bemis plant was bought by a company selling Himalayan salt products. I think they just use it as a warehouse. I had read that they were going to ship by rail but I haven't seen any cars on the siding(s). Atleast the concrete plant had shipped some loads, if the siding is into the plant they could get Raw materials in- stone and cement and ship finished products out.