High-grade hard coal (anthracite) was chosen as fuel for the K-28s since it was easily obtained from mines close to the D&RGW's narrow gauge railyards. It is loaded into the tender's bunker. The locomotive fireboxes were designed to use coal and their efficiency charts were prepared with coal in mind. Though other railroads converted coal locomotives to be oil-fired, the K-28s were never considered for this expensive modification.
Quick facts
Big mound of coal
Fueling possibilities