Even on land they aren't cleaned up (see http://2.bp.blogspot.com/-xVwr9gMopMY/UGhek26WYJI/AAAAAAAABzQ/lgiAZ70C6xA/s1600/DSC_0280.JPG http://2.bp.blogspot.com/-

Even on land they aren't cleaned up (see http://2.bp.blogspot.com/-xVwr9gMopMY/UGhek26WYJI/AAAAAAAABzQ/lgiAZ70C6xA/s1600/DSC_0280.JPG http://2.bp.blogspot.com/-xVwr9gMopMY/UGhek26WYJI/AAAAAAAABz... for example, on Kerguelen island there is large area littered with missiles remaining from France-USSR testing in the 60's) so under the sea? Not a chance.