Environmental assessment1 of human activities with the potential for significant impacts on marine species, habitats and ecosystems is an essential component of any ocean governance regime. The process of prior environmental impact assessment (EIA) with its recognised stages of screening, scoping and public consultation is critical to minimising adverse human impacts on these areas and developing suitable mitigation measures for the life of such activities and beyond. Transboundary environmental impact assessment (TEIA) can alert States to the potential for transboundary harm from certain activities in marine areas and in many cases requires States to notify and consult other States where risks to marine areas under their jurisdiction emerge.2 EIA is an integral component of a precautionary approach to human activities with the potential for adverse effects on the marine environment. Undertaking prior EIA and ongoing monitoring of activities with the potential for adverse effects on the marine environment is also vital in incorporating environmental concerns into the development process and facilitating sustainable development. 3 The related but more recently developed process of an overarching strategic environmental assessment (SEA) can be even more beneficial in mitigating the adverse impact of plans, policies and programmes for the development of broader scale marine areas where a range of human activities occur over longer time frames.4
This chapter will examine how overarching provisions in the UN Convention on the Law of the Sea (UNCLOS)5 and other global instruments such as the Convention on Biological Diversity (CBD )6 apply to environmental assessments in marine areas. It will then discuss the concept of SEA and potential elements in this process. It will analyse the relationship between EIA and SEA
and the relevance of SEA to marine spatial planning. Some concrete examples of SEA and TEIA in a marine context will also be considered. Finally, the chapter will consider how SEA and TEIA might be implemented in the East Asian Seas.