> It could be dumped in the ocean

FFS no. This is the reason environmentalists don't trust the nuclear industry.

This is a "no" purely for optics; it would be perfectly safe.

Citation needed.

There's approximately 1.4 * 10^21 kg of water in the ocean. There's about 2.3 * 10^6 kg of waste per year. 10^-15 is a really small number.

(Hell, seawater is already ~3.3 * 10^-9 uranium.)

Why is heavy metal concentration such a problem in fish right now?

It isn't. And unlike heavy metals, nuclear waste becomes safer over time.

Well that's a lie. https://americanpregnancy.org/healthy-pregnancy/is-it-safe/m...