Sinking
From Chemical Spill Response
A sunken ship with its cargo still on board may not pose an immediate threat if the cargo tanks or packages are still intact and no chemical release takes place.
Packaged goods may stay on board or spread over the sea floor depending on the nature of damage and the differing behaviour of the packages.
The ship or its cargo can be removed from the sea floor in a salvage operation. If left on the sea floor the ship or the packages may sustain further damage with further substance release.