It turns out, oddly enough, that "dirty coal" harbors Rare Earth Elements. REEs have become increasingly important in manufacturing, especially in phones and computers, and for a while now, China has had a monopoly of sorts on them, as they produce 95% of REEs at present. Pantsuit famously crowed during her failed campaign that she intended to put a lot of coal miners out of work; as it happens, she crowed too soon. REE extraction from coal and coal byproducts seems economically feasible, which means that we can do it here rather than rely upon Chinese supplies.
Kentucky, W. Virginia, Illinois, and Pennsylvania are among the states with extensive coal deposits, and test facilities for REE extraction are being constructed in at least two locations.
The "war on coal" appears to have suffered a setback.