DuPort railways

The plant just south of Fort Lewis,Washington also had such a railway. Included a branch down to a dock in salt water (Puget Sound) where they transfered to their company ship for delivery to British Columbia and Alaska. The dock line had a tunnel under the Northern Pacific double track mainline. Remanents are slowly going south.
There is a museum in the town of DuPont, open Sunday afternoons. Suggest checking ahead of time via GOOGLE.
I trust that you are familiar with the Cumbres & Toltec Scenic's rebuilt critter. Reportedly headed for Alamosa as their carshop switcher.