The historic problem of just 'drop it in the ocean' is that (so far) it almost always comes back to bite you. Hence the thousands of rusting barrels of DDT off the coast of California.

https://www.latimes.com/environment/story/2021-04-26/ddt-was...

Did I say thousands? Wow.

Don't ever trust anyone that says "We'll just safely dispose of that in the deep ocean.".