Sustainable governance of seabed minerals activities in the Cook Islands is underpinned by a dedicated ecosystem-based management framework. This framework supports the organisation of knowledge, design of work programs, environmental monitoring, environmental risk assessment, and policy and regulatory decision‑making. A national‑scale Strategic Environmental Assessment (SEA) was delivered within this framework, comprising a risk‑based Environmental Effects Assessment, Cumulative Impact Assessment, and Regional Environmental Management Plan.
As the world’s first SEA for deep‑sea minerals activities, the approach was designed to be iterative, allowing future updates to address uncertainty as new data becomes available. The SEA assessed four key drivers: three minerals extraction activities (polymetallic nodules, rare earth element muds, and cobalt‑rich crusts), and Tier 2 seabed exploration. For each activity, operational pressures (e.g. habitat disturbance, noise, lighting, water quality changes, sedimentation, and vessel movement) were assessed for their environmental impacts, both for individual projects and possible cumulative developments.
To assist decision making, environmental impacts were assigned significance ratings based on severity, extent, and duration, with confidence ratings highlighting uncertainty and guiding precautionary management and future research priorities.