Coal ash is toxic and people exposed to the ash have higher risks for cancer. Ash piles now pollute groundwater from leaking ash ponds in the US, including NC, WI, IL, TN, IN and MI. The ash when used in other products continues to create problems.
Ash piles at manufacturing plants leach into groundwater, especially when exposed to weather. Unless the ash is totally encapsulated, it creates health hazards. Who wants drywall made with toxic coal ash? It's used as a soil supplements for farming and chicken production.
The only time it isn't a hazard is when it's "encapsulated." It's used as a road filler and it's encapsulated until the road cracks and releases ash or when the road is ripped up and piles of discarded ash join garbage dumps. The ash then is lifted by the wind into neighboring communities.
Small seeds from fields in the Midwest turn up in NYC! Ash is not just a local problem. An ash pile in TN in 2008 flooded the town and killed several residents. These ponds, nearly 1,000 of the ponds, are located throughout the US!