CASTEAUR: A tool for operational assessments of radioactive nuclides transfers in river ecosystems

Institute for Protection and Nuclear Safety, DPRE/SERLAB, Laboratory of Environmental Modelling, CE Cadarache, bâtiment 159, BP. 1, 13108 Saint-Paul-lez-Durance cedex, France

Abstract

CASTEAUR (french acronym for Simplified CAlculation of radioactive nuclides Transfer in Receiving WATERways) is an operational tool to assess the impact on fluvial ecosystems of both accidental and routine radioactive releases. This code is organised over a simplified representation of the hydrographic network, on which simplification was applied to the five domains : hydraulics, sedimentary dynamics, ecology and radioecology. The ecosystem could be described by six components which are water, suspended and settled matters, primary producers, first order consumers and fish. According to time and space and with the possibility to take into account four kinds of radioactive releases, from pulse to continuous pollution, CASTEAUR assesses the radioactive nuclides concentrations in these components. These concepts are formalised in a prototype, which offers the possibility to combine the different kind of releases, pollutants and ecosystem components. This paper presents these concepts (hypothesis, models and functionalities) and some application example.