There’s a town in Pennsylvania called “Centralia”…. It’s a ghost town, because the coal mine under the town caught fire in the 70’s and has never gone out….they had to evacuate the town….there are spots you can touch the ground and it’s hot….vents of toxic gas…..eerie place….. the remnants of what once was….@Buzzard...which way is the wind blowing....any sign of rain yet....?....
Where we lived in NE UK we had near the surface (crap) coal seams....and fires could smolder for years along the seams...then it would break through the surface and it was bloody dangerous for anyone standing on them and dropping through to burning coals.