The Environmental Liability Directive (ELD), based on the “polluter-pays principle”, aims at ensuring that significant environmental damage (harm to biodiversity, water or land) is restored. The Directive provides for, and regulates, the relationship between public authorities and potential or actual polluters. The operator, who operates or controls the occupational activity is liable for the environmental damage and for the costs of the preventive or remedial measures that it has to take. If these measures are taken by the competent authority itself, the latter is entitled to recover the costs from the operator.