MOIRA-PLUS: a decision support system for the management of complex fresh water ecosystems contaminated by radionuclides and heavy metals

The accidental release of radioactive substances into the environment leads to the necessity of applying suitable countermeasures for the restoration of the polluted environment. However, despite their obvious benefits, such interventions may result in detrimental effects of economic, ecological and social nature that must be carefully evaluated. MOIRA–PLUS is a PC-based user-friendly, Computerised Decision Support System (CDSS) that helps decision makers to choose optimal countermeasure strategies for different kinds of aquatic ecosystems and contamination scenarios. CDSS MOIRA-PLUS is based on: a) Validated models to evaluate the behaviour of radionuclides in contaminated water bodies and biota and to assess the effect of countermeasures on the contamination levels; b) Models to assess the radiation dose to people and biota (fish) by the relevant exposure pathways, the effect of countermeasures, and the associated economic impact; c) Multi-Attribute value Analysis (MAA) module to assess the effectiveness of different management strategies by accounting for the social, the ecological and economic detriments and costs in relation to their benefits. The flexible structures of the environmental models implemented in MOIRA-PLUS allow the application of these models to several other types of pollutants, such as heavy metals. The CDSS can be applied to complex water systems comprised of lakes, reservoirs and rivers. The main principles underpinning the functioning of the CDSS MOIRA-PLUS will be described and discussed.