I’m not sure why you think dispersing nuclear waste into our environment instead of isolating it is a good idea.
If it’s just a thought experiment from a mathematical / chemical perspective, maybe someone else would like to take on the question and do the math.
From a sociological and logistical perspective, it’s just not gonna happen. Pretty sure people’s tolerance for radioactive materials anywhere near them is zero. There isn’t any amount of radioactivity / danger that is considered socially acceptable.