Well, one reason is that a lot of people casually assume that the baseline level of radiation in the natural environment is 0.0000000...., but it's not.
Uranium has been extracted from seawater before. It's not economically practical, but it can be done, because seawater has uranium in it already. Tritium is also already in there.
Issues of concentration at the point where it is put into the ocean can be an issue, but once dispersed this won't turn the pristine, 0.0000000...% radioactive ocean into a radioactive hellscape, it represents an impercetible percentage increase of what is already there. That doesn't mean we shouldn't think about the implications, but "thinking about the implications" shouldn't start from incorrect understandings of the nature of the current world.
Earth is an amazing environment. It does an incredible job of giving us a low-radiation environment, compared to most of the rest of the universe which ranges from "dangerous" to "radioactive wasteland". But it's not perfect and we are not at a flat 0 even here.
Uranium has been extracted from seawater before. It's not economically practical, but it can be done, because seawater has uranium in it already. Tritium is also already in there.
Issues of concentration at the point where it is put into the ocean can be an issue, but once dispersed this won't turn the pristine, 0.0000000...% radioactive ocean into a radioactive hellscape, it represents an impercetible percentage increase of what is already there. That doesn't mean we shouldn't think about the implications, but "thinking about the implications" shouldn't start from incorrect understandings of the nature of the current world.
Earth is an amazing environment. It does an incredible job of giving us a low-radiation environment, compared to most of the rest of the universe which ranges from "dangerous" to "radioactive wasteland". But it's not perfect and we are not at a flat 0 even here.