It's a reasonable question. I think the linked wiki article addresses it though. There are at least concerns about ground water contamination and about heavy metals.
If dilution is so straightforward then why wasn't the waste mixed with a large volume of sea water and then dumped far out at sea to begin with? That probably would have been cheaper.
If dilution is so straightforward then why wasn't the waste mixed with a large volume of sea water and then dumped far out at sea to begin with? That probably would have been cheaper.