Canadian coal trains is a big subject...
CP, CN and BC Rail loaded unit trains in BC, Alberta and Saskatchewan (just CP and CN in the latter two provinces)
The CP M630s were ordered along with the first CP bathtub cars for Kaiser resources unit train service from Fording River to Robert's Bank, BC hauling metelurical coal for Japanese Steel Mills.
They Ran in 100-105 car trains with mid-train robots and manned helpers over Roger's Pass.
The M630s proved unreliable in this service and were replaced when the 5800 series SD40-2s arrived in 1974.
Interesting side note the original cars were painted Action Red, however the effects of coal dust were quickly noticed and all subsequent orders were painted Black.
The original cars were never repainted however, they're still red under all the coal dust!
