Most interesting.
Grew up in Kankakee, Illinois, where one could go to one of the limestone quarries on hot summer days, when i was a kid in the 50s, and go swimming.
Water so clear you could see down ...30-50 ft... and see the locos and dumpcars still on the tracks on the ledges near the sides. In the center, it was a deep dark hole, and tales were told about 'things' getting thrown there...to make them disappear...
Always gave me the creeps seeing locos and cars there... feeling that someone might still be sitting in there.
Many limestone quarries scattered across northern Illinois, for building material and for burning into clinker to locally make cement. Virtually all these quarries used little 'dinks' as my father called them (for dinkey?), and my guess is that they were all 2'... a very commom industrial gauge.
In Chicago, at the big steel works on the south side, they used a 3' gauge, (chronicled in a recent issue of Railroad History) and was extant until the 1980s... large GEs, looked like maybe 75-90 tonners, all center cabs, but later equipped with ...remote control, so one man could operate them from the front or rear step, while switching...
too bad those locos aren't available today, for ballast hauling on the east end...