If we take a glance at the scientific literature, particularly those on soil treatments, the number of articles, reports and books available are uncountable. Suddenly the question comes to mind – which treatment is best for a define case? We know that all of them differ from each other and have their advantages and disadvantages, many factors come into play when deciding on the best technology. In addition, variations in boundary conditions defined between technologies, produce distorted environmental impact results. Thereupon, a balance between environmental, social, and economic costs and benefits must be required in identifying the optimal remediation solution. Key indicators need to be defined in each case.
More precisely, an indicator is a single characteristic that can be compared between the different tools to evaluate their relative weight in each technology. An important perspective about the indicators is how they are measured and how all of them are ultimately balanced in the evaluation of potential remediation strategies.
Determining the most appropriate course of action when faced with soil or groundwater contamination requires the consideration of technologies or approaches that can feasibly remove the contamination to the required target level within project-defined time and cost constraints. Consequently, the technology selection phase in the planning process consists of two steps: identify the feasible technologies and evaluate the financial, social and environmental financial costs of the different alternatives.
On the other hand, Decision Support Systems (DSSs) provide us a structured method of comparing these alternative courses. On the commercial market there are many examples of soil and groundwater remediation. Some DSSs examples are MMT (Mega-site Management Tool), DESYRE (Decision Support System for the Rehabilitation of contaminated sites), SBR (Sustainable Brownfields Redevelopment tool), CO2 calculator, SRT (Sustainable Remediation Tool), REC (Risk reduction, Environmental merit and Costs tool) or GoldSET.
Between all the above DSSs described, Alistair Beames and his colleagues from VITO established the use of four of them for its study on a specific contaminated area of Antwerp, exactly a petrochemical storage and distribution facility, providing a meta-analysis of sustainability appraisal of four technically feasible remediation alternatives proposed for the site: ex situ soil washing, ex situ thermal desorption, in situ thermal desorption and monitored natural attenuation.
The results generated after this study are compiled in a more detailed article titled Sustainability appraisal tools for soil and groundwater remediation: How is the choice of remediation alternative influenced by different sets of sustainability indicators and tool structures?
About the tools used, the CO2 calculator is an example of a standard environmental footprint calculator and considers an inventory solely focused on energy consumption and CO2 emissions. SRT and REC are tools with larger inventories across a range environmental impacts that also account for financial costs. SRT aggregates the different criterion scores according to economic valuation. REC integrates different criterion scores within a multi-criteria analysis framework. GoldSET is an example of tools used by consultants on behalf of clients and considers a broader range of impacts across the three pillars of sustainability (environmental, social and economic), many of which are measured qualitatively.
In conclusion, the results generated by these tools differ from one another when applied to the same case study, due to differing indicator sets and aggregation methods. Clearly broadening the scope of the assessment from only a few environmental indicators and financial costs to also considering social impacts and indirect economic impacts will influence the sustainability performance of the remediation alternatives.
All the information is available on the article
Beames A, Broekx S, Lookman R, Touchant K, & Seuntjens P (2014). Sustainability appraisal tools for soil and groundwater remediation: How is the choice of remediation alternative influenced by different sets of sustainability indicators and tool structures? The Science of the total environment, 470-471, 954-66 PMID: 24239816