Supporting Multicriteria Group Decisions with MACBETH Tools: Selection of Sustainable Brownfield Redevelopment Actions

Decisions on sustainable development issues usually involve multiple stakeholders with multiple and often conflicting perspectives. Participatory processes along with sound multicriteria analysis tools and models for cooperative group decision-making can support stakeholders to select the best actions. This article presents a real-world application of the MACBETH socio-technical approach for the sustainable redevelopment of a brownfield. The project is aimed at presenting a visible and high-profile participation process that could trigger a domino effect for other mine brownfield redevelopment projects to follow in Portugal. A group of key stakeholders was chosen to represent the main evaluation perspectives of the decision context. Structuring the problem was carried out during a decision conference. As it was not possible to apply a full decision conferencing procedure, we conducted at distance a novel participatory process supported by several decision support tools (M-MACBETH, MACBETH Voting, and Web-MACBETH) to evaluate and select the actions under a weak sustainability assumption. Two alternative multicriteria aggregation schemes were applied in order to assist the group in evaluating the added value and doability of the proposed actions. New measures and methods to analyze the dominance relationships between the actions were proposed, further assisting the group in the priority selection of the most effective and doable sustainable actions. Ex-post evaluations of the proposed approach identified its associated benefits and shortcomings. By-products of the research include case study evidences suggesting that decision conferencing yields more aligned evaluations than a nominal group process, and that each brownfield redevelopment action is typically assessed as having consequences across multiple sustainability criteria.