Is there dispute over the long term toxicity of nuclear waste? It's not hard to find numerous toxic, long lived isotopes. The world has no shortage of waste and the volumes are growing, not shrinking.
Im not a proponent of coal, and at the scales my part of the world needs, hydro fills most the need. Yeah, it needs maintaining but that's unlikely to be more costly than nuclear.
No, but there is a dispute over how dangerous it is - or more specifically, how many people it's likely to kill.
We're close to capacity for the world's utilization of hydro. It can only grow ~20% in the next 30 years - which would let it... Take ~10% of coal's contribution to power generation.
Hydro power is generally cheaper then coal. If we could use more of it, we would be.
https://en.m.wikipedia.org/wiki/Long-lived_fission_product