I grew up in Joplin, MO which is part of this mining area. The remnants of that industry have left this region highly polluted. Much of the soil in these towns is contaminated and some places like Picher, OK have been declared superfund sites. Picher is a ghost town now, completely abandoned. https://en.wikipedia.org/wiki/Picher,_Oklahoma The tailings from the mining operations are referred to as “chat” and were depo…
I spent countless hours as a kid swimming in flooded coal mining strip pits, collecting fossils from those exact sorts of piles you mention (there's some cool shit there! They dig up so many layers so you get stuff separated by tens or hundreds of millions of years all accessible on the surface, shell fossils were extremely abundant and there were some sections full of fossil ferns of the same species more often associated with Illinois) and if I biked a couple miles down an arrow-straight road from our house, I could see an operating coal power plant in the distance, pumping nastiness into the air.
I reckon cancer's in my future. Whoops.