1. Significance and role of principles and rules of prevention and mitigation

Prevention and mitigation are two tools used for the protection of the environment. The principle of prevention purports to prevent specific harms from arising, e.g., alteration of the environment, damage to people or the environment, interference with legitimate and legal uses of the environment, and overload of the assimilative capacity of the environment.¹ The principle of mitigation, on the other hand, purports to minimize the occurrence of such specific harms. Principles of prevention and mitigation work together in the international regulation of pollution or environmental harm.

Prevention is less costly than reparation both in economic and social terms because of the intrinsic nature of pollution or environmental harm - i.e., their long-lasting and irreversible detrimental effects upon people and the environment. Consequently, more importance has been given in international environmental law to the principles of prevention and mitigation than to reparation. While the principle of liability does have a deterrent effect on environmental harm, preventive and mitigative measures have an even more direct and effective deterrent effect.