When you flip the switch, the light comes on. It's something we all take for granted, and it's possible because of coal energy. But burning coal for electricity leaves something behind: coal ash, containing things like barium. And arsenic.

We burn a lot of coal in this country, producing huge amounts of coal ash that we have to figure out what to do with.

At the D.B. Wilson power plant in Western Kentucky, that coal ash goes into unlined landfills. It’s been seen in ditches and ponds that flow into the Green River, and it's also been seeping into the groundwater--possibly for as long as 18 years.

Coal ash is supposed to be regulated, and the regulations are supposed to keep people safe from it. So what went wrong at D.B. Wilson? WFPL's environment reporter Ryan Van Velzer joins us on this episode of Recut, to explain.