Coal is shockingly nasty. Combustion concentrates heavy radioactive elements that are present in the coal. Coal and nuclear plants can't be built too close together or the exhaust from the coal plant will set off the radiation alarm at the nuclear plant.

It also does the same thing to heavy metals in the coal like arsenic, lead, cadmium and mercury. More than 90% of coal is carbon and therefore becomes CO2, but because of the huge difference in energy density, the coal plant has to burn millions of times more coal than nuclear reactors consume uranium, and thereby generates tens of thousands of times more toxic and radioactive coal ash than the nuclear plant generates nuclear waste.

Then they put the stuff into "wet surface impoundments" which is industry for dumping the toxic sludge into a lake. Those things frequently poison entire towns without any kind of terrorist attack.