At the Colorado Railroad museum we are also still 100% coal fired steam. We also buy our coal from the King II Coal mine owned by GCC energy. Their parent company is a cement plant in Mexico and nearly everything they mine goes there. I was told a couple years ago that they had a special screen for smaller coal for the D&S. I said I would like to try that size on our next delivery, when the truck arrived I was disappointed to find it lump as usual. Never heard anything more about it again, I guess there was an issue. So as you can imagine we still get the mine run/lump coal to this day. We deal with the same issues as others have described with the size. 491 doesn't mind it much, in fact the larger pieces are great for the back corners, but it gets problematic with 20 and 346. We keep hammers on the engines and break up some of the big stuff when we can. We obviously have more time for this than the D&S, C&TS or NN has when running.
Jeff Taylor
CRRM curator of equipment and rolling stock.