Cost-benefit analysis as a part of sustainability assessment of remediation alternatives for contaminated land

There is an increasing demand amongst decision-makers and stakeholders for identifying sustainable remediation alternatives at contaminated sites, taking into account that remediation typically results in both positive and negative consequences. Multi-criteria analysis (MCA) is increasingly used for sustainability appraisal, and the Excel-based MCA tool Sustainable Choice Of REmediation (SCORE) has been developed to provide a relevant and transparent assessment of the sustainability of remediation alternatives relative to a reference alternative, considering key criteria in the economic, environmental and social sustainability domains, and taking uncertainty into explicit account through simulation. The focus of this paper is the use of cost-benefit analysis (CBA) as a part of SCORE for assessing the economic sustainability of remediation alternatives. An economic model is used for deriving a cost-benefit rule, which in turn motivates cost and benefit items in a CBA of remediation alternatives. The empirical part of the paper is a CBA application on remediation alternatives for the Hexion site, a former chemical industry area close to the city of Göteborg in SW Sweden. The impact of uncertainties in and correlations across benefit and cost items on CBA results is illustrated. For the Hexion site, the traditional excavation-and-disposal remediation alternative had the lowest expected net present value, which illustrates the importance of also considering other alternatives before deciding upon how a remediation should be carried out.