I wonder if they dug up an already burning seam, or if it caught fire after it was exposed. Seems like digging out an already burning seam would be pretty futile, unless they are just getting this part of it out of their way.

And question for those who might know: How do underground coal fires, like the one in Centralia, PA, get enough oxygen to keep burning? I can understand that exposed shafts and large cracks in the Earth might let some O2 in, but wouldn't you seal those up to stop the fire? This has long been a burning question for me.