St. Maries River Railroad EMD SW1200 No. 501 switches the PotlatchDeltic lumber mill at St. Maries, Idaho, on September 27, 2021. The locomotive has just emerged from the covered plywood loading dock of the main building in the large complex with two loaded boxcars of plywood, and now carefully negotiates mill trackage, along with vehicle traffic, before getting back to the STMA yard along the “main line” at this location.