DSS-ERAMANIA: Decision Support System for Site-Specific Ecological Risk Assessment of Contaminated Sites

Abstract

The DSS-ERAMANIA is a decision support system implementing a site-specific Ecological Risk Assessment (ERA) procedure and supporting the experts and the decision makers in the assessment of contaminated soils. It was developed according to a Triad approach, where the results provided by a set of measurement endpoints are evaluated and integrated to support the assessment and characterization of ecosystem impairment (i.e. assessment endpoint) caused by the soil contamination. In the Triad approach, the measurement endpoints refer to three Lines Of Evidence (LOE): environmental chemistry, ecotoxicology and ecology, whose integration should pragmatically reduce the uncertainty in the risk estimation. For the DSS, a framework including three subsequent investigation levels (i.e. tiers) was implemented, that enables the completion of the risk assessment once the provided answer is unequivocal as characterized by a relatively small uncertainty, ensuring at the same time an adequate financial investment. The DSS includes two modules: “Comparative Tables” and “Integrated Ecological Risk Indexes”, both based on Multi Criteria Decision Analysis (MCDA). Module 1 (“Comparative Tables”) aims at comparing the different measurement endpoints belonging to each LOE (i.e. bioavailability tools, toxicity tests and ecological observations) to guide the expert/decision maker in the choice of the suitable set of tests to be applied to the case study for each tier of investigation. Module 2 (“Integrated Ecological Risk Indexes”) provides qualitative and quantitative tools allowing the assessment of terrestrial ecosystem impairment (i.e. the impairment occurring on biodiversity and functional diversity of the terrestrial ecosystem) by integrating complementary information obtained by the application of the measurement endpoints selected in the first module. The two modules were implemented in a software application and validated using the Acna di Cengio contaminated site (located in Savona province, Italy). The objectives, functionalities and structure of the DSS-ERAMANIA will be presented and the main outcomes of the DSS application to the case study will be discussed.