Testing models for predicting the behaviour of radionuclides in aquatic systems.

The paper describes the main results of the international EMRAS model testing exercise for radionuclide transport in watershed-river and estuarine systems. The exercises included the following scenarios: multi-point source of 3H discharge into the Loire River (France), radioactive contamination of the Dnieper–Southern Boug estuary (Ukraine), remobilisation of radionuclide contamination from the Pripyat River floodplain (Ukraine) following the Chernobyl accident, release of radionuclides into the Techa River (Russia) and behaviour of 226Ra in the Huelva estuary (Spain).