Editorial note

The Convention on Environmental Impact Assessment in a Transboundary Context, which was adopted under the auspices of the UNECE, is designed to promote co-operation between States whose environmental, cultural or socioeconomic conditions are likely to be affected (referred to as ‘transboundary impact’ in Article 1(viii)) by another State's activities.

The Convention requires States to carry out an environmental impact assessment procedure for all activities listed in Appendix I that are likely to have a ‘significant adverse transboundary impact’ (Article 2(2)). That procedure is to allow for public participation and must result in production of the environmental impact assessment documentation set out in Appendix II (Article 2(2)). Environmental impact assessments as described in the Convention are required for all activities listed in Appendix I which are likely to cause ‘significant adverse transboundary impact’ (Article 2(3)). Parties may decide, by mutual consent, to extend the Convention's application to activities not listed in Appendix I but which are likely none the less to cause a ‘significant adverse transboundary impact’ (Articles 2(5) and 3(7)). Criteria for determining ‘significant adverse impact’ are set out in Appendix III of the Convention (Article 2(5)). States planning an activity likely to cause a ‘significant transboundary environmental impact’ are required to notify other States likely to be affected of the proposed project (Articles 2(4) and 3(1)) and allow the public of affected States to participate in the environmental impact assessment procedure in the same manner as its own public (Article 2(6)).