The Obligation of EIA in the International Jurisprudence and Its Impact on the BBNJ Negotiations

Environmental impact assessment (EIA) has been widely recognized as a crucial instrument for sound decision-making that will promote environmental conservation and sustainable development. International jurisprudence has clarified the obligation of EIA under customary international law, especially concerning its legal status, threshold standards, and procedural requirements, as well as the issue of State responsibility. As suggested by this article, international tribunals tend to adopt a procedural-oriented and State-based approach regarding the obligation of EIA, leaving more discretion to the States pursuing the proposed activities. This approach is insufficient to realize the role of EIA in fostering sound decision-making. As for the BBNJ negotiations, in light of the legal status of the Area in international law and the established rules governing the issues of EIA, especially the three Regulations and Recommendations adopted by ISA, the future implementation agreement should reinforce international regulations regarding the substance and implementation of EIA obligations.