Heavy metal and radiological exposure is not a boolean safe/unsafe.

Sure, but the important point is that we already have infrastructure deployed to detect and remove uranium from the water supply on account of naturally occurring uranium.

That's...not a very good point.

It is. Presumably your fear is that uranium from spent fuel might somehow contaminate water supplies, and cause illness. But we already monitor water for contamination from naturally occurring uranium, and have the infrastructure to remove it.

So what happens if uranium from nuclear waste somehow works its way into the water supply? We'll detect it and remove it in water treatment, just like how we remove contamination from naturally occurring uranium.

It's a terrible argument because it burdens someone else with the risk of cleaning up the mess.