[vihren]

We are not discussing nuclear waste here. It is highly concentrated and disposed of in the end of the fuel cycle. What you should be comparing with is the radioactivity that is released in the environment during the operation of the plant. That is mostly Tritium and isotopes of Xenon, definitely no heavy metals. Tritium is a very low energy beta emitter and is mostly harmless. Xenon is a noble gas and a beta emitter, so again not very harmful.

The WHO guidelines on alpha emitters (all elements you cite that are contained in fly ash) is 1 Bq/l in drinking water. So depending on how and where this ash goes to, you can definitely cause some significant damage with it.