Quality assessment of environmental simulation scenarios : scientific, expertise, interpretive and participatory methods based on mathematical, epistemological and socio-anthropological approaches

(eng) Simulation scenarios, defined as parameters with a physical meaning used with scientific models, are often used to supplement the limits and avoid the costs of experimental approaches, and to forecast the environmental consequences of regulatory decisions. Their quality assessment is important to support decisions in the public domain and avoid choiceswith unwanted effects. Building onmathematical, socio-anthropological, philosophical, and scientific developments, this study defines a generic framework for scenarios quality assessment, develops specific methods and adequacy criteria for regulatory scenarios and tests their applicability, limits and interest. Quality is defined as the adequacy for a given use. Representativeness, theoretical consistency, logical consistency, juridical conformity and political criteria are defined. Two routes for quality assessment are defined: an expertise route making interpretation choices transparent, and a participatory route opening interpretation choices to citizens. Those routes are tested, respectively, with case studies of diffuse pollution simulation scenarios for groundwater and bees exposure to pesticides. The framework allows to assessmultiple quality components, taking into account the links between them(including the juridical, scientific and political components) while preserving their specificity. It highlights the limits of the scientific knowledge in a regulatory context, makes transparent the choices and uncertainties, and allows to assess the social acceptability of such uncertainties and of the use of the scenarios. Due to the lack of a binding political mandate in our case studies, the possibility of the incorporation of the framework in formal democratic processes is still to be demonstrated.