Sunken oil tanker: How to protect the high seas environment?

Eight days after the collision with the cargo vessel, due to unknown reasons, the Iranian oil tanker Sanchi fire started and it was sunk in eastern China Sea last Sunday. Members of 30 members of the group are missing with the slightest possibility of existence - and the fear of environmental damage has spread. High seas are often the source of controversy to protect wildlife and marine ecosystems. Absence of strict international rules in water outside national maritime boundaries - which covers half the surface of the planet - reflected in many brown areas. SOURCE http://www.dw.com/en/sunken-oil-tanker-how-to-protect-the-high-seas-environment/a-42150179