"... Your sins are forgotten
They’re on the bottom
Of the ocean floor
"Your sins are erased
And they are no more
They're out on the ocean floor."
~ Ocean Floor as performed by Audio Adrenaline
"You will again have compassion on us; you will tread our sins underfoot and hurl all our iniquities into the depths of the sea." ~ Micah 7:19
Unless you can afford to send Dr. Robert Ballard down there after them, that sounds really remote; pretty much irretrievable.
So why bother?
Let 'em sink and die.