This makes no sense. Russia has actual nuclear weapons, it can "obliterate" Ukraine (or Switzerland) on a whim with them, if they decide to. Also, as you can verify by looking at the containment zone of Chernobyl catastrophe, full blown meltdown/explosion of a nuclear reactor doesn't really "obliterate" a country size of Ukraine.

> The waste - nobody wants it - it's a hazard for tens of thousands of years

No, it is not hazardous for "tens of thousands of years".