Application of analytic hierarchy process for analysis of impact significance in EIA of oil and gas industry

Impact significance determination is one key task required of all EIA undertakings. A major issue in EIA analysis is the subjectivity resulting in, inconsistencies in experts’ and stakeholders’ judgment. However, Analytic Hierarchy Process (AHP) can serve as a check for inconsistencies and tool for aggregation of the different experts’ and stakeholders’ opinions on impact assessment. This study investigated the integration of AHP into EIA impact significance determination to assess the effect of consistency and inconsistency in stakeholder judgments. A case study to investigate an application of the proposed method in a major oil pipeline’s replacement project is presented. It was observed that the opinions of both experts and stakeholders were uniform on some impacts such as land use, water contamination and an increase in the cost of health services, representing 18.75% of all the identified impacts. Conversely, there were differences in opinions on other impacts revealing what could be a cause of serious disagreement between the company and the community. It was also observed that, although consistency in judgment is critical, it is not always very easy to obtain when dealing with many stakeholders. This integration demonstrated the ability of AHP to serve as an excellent decision aid for managers during environmental impact assessment. This could also help authorities prioritise risk management plan and allocate resources optimally when dealing with identified impacts of a project.