Both Cs137 and Sr90 have half-lifes of about 30 years. So of what was deposited, just under half of it is left. It'll likely be centuries before the exclusion

Both Cs137 and Sr90 have half-lifes of about 30 years. So of what was deposited, just under half of it is left. It'll likely be centuries before the exclusion zone is really just a bunch of land again.