Developing a Framework for Oil Spill Environmental Liability Assessment in the Nigerian Offshore Context

The determination of environmental liability for offshore oil spills in Nigeria has remained contentious, legally contested, and scientifically inadequate, with the absence of a rigorous, nationally accepted environmental liability assessment framework contributing to persistent impunity and inadequate remediation of damaged ecosystems. This dissertation develops a comprehensive Environmental Liability Assessment Framework tailored to the Nigerian offshore legal, ecological, and institutional context, drawing on natural resource damage assessment methodologies from the United States, European Union, and comparative African legal systems. The framework development involves four research phases: a systematic review of existing global natural resource damage assessment methodologies and their transposability to the Nigerian context; a series of simulated oil spill environmental impact scenarios modelled using the General National Oceanic and Atmospheric Administration Oil Spill Modelling program coupled with an ecological exposure-response framework for key Nigerian shelf habitats (mangroves, seagrass, coral, pelagic fish habitat); a multi-stakeholder Delphi consultation with 40 Nigerian and international experts from environmental law, oceanography, ecology, economics, and regulatory institutions to achieve consensus on framework components; and a retrospective application of the framework to three historical spill events to test its operational feasibility and compute illustrative liability estimates. Theoretical contributions include the development of an ecosystem services valuation module calibrated to the economic context of Niger Delta fishing communities and a temporal recovery trajectory model for tropical mangrove systems based on synthesis of West African restoration literature. The framework is proposed for adoption under a reformed Petroleum Industry Act environmental regulation schedule. Keywords: oil spill liability, environmental damage assessment, Niger Delta, natural resource damage, offshore regulations