A lot depends on the era you are modeling.
Here in Ottawa/Hull the E. B. Eddy Company used to have a huge pile of pulp logs behind the old Grind-wood Mill. The logs were cut in Northern Ontario and Quebec and floated down the Ottawa River. They were brought inside the mill on a simple conveyor, dropped down a chute through a heavy rubber curtain into a small waist high canal. The curtain didn’t stop those working the area from getting soaked when the logs jammed in the chute, and that old stone mill was cold and damp. It was their job to pole the logs along the canal to feed the grind stones that made pulp out the logs.
As decades passed, the concern about fire increased as the internal temperature of the log pile increased. In 1900, Hull and a good chunk of Ottawa had been destroyed in the
Fire of 1900 which started in downtown Hull and was fueled by the old wooden paper and lumber mills in the same area.
http://www.biblioottawalibrary.ca/images/ottawa_room/fire_3.jpg
To solve the problem, the company bought a number of huge electric chippers. The logs were moved, fed through the chippers and a new pile of wood chips grew. It was scary to see how fast those chippers ate a pulp log.
As the years passed, Ottawa and Hull grew with E. B. Eddy stuck in between their increasing modern downtown areas. To break down the logs chips into pulp and whiten it for paper, the plant ran a sulphide mill. Anyone who has passed a large paper mill will be familiar with the rotten eggs smell it would generate. Having that smell waft over the Supreme Court, the Federal Parliament Buildings and other downtown businesses did not sit well with the either the Municipal or Federal Bureaucrats. There was ralk of movingthe plant, but as E. B. Eddy was a large employer a compromise was reached. The pulp was processed in other more remote mills and transported as laps by trucks, lots of trucks. The laps look like large white blankets folded on skids. After the wood chip pile was depleted, the sulphide mill was shut down.
E. B. Eddy also had a railway running through most of their sprawling plant. Little, green industrial locomotives would move cars between the different mills. As the cities around it grew however, rail lines in the downtown areas disappeared and most were replaced with roadways and buildings. Likewise Eddy’s industrial railway disappeared and the spur to the CP Rail was lifted.
Later the obsolete Grind-wood Mill was gutted and became the head-end for a new, fine paper mill across the street. Fine paper requires Kaolin which is usually moved by railway tank cars. The railway spur was put back in, and service was provided by the Quebec-Gatineau Railway, one of many short lines run by the Genesee & Wyoming.