Comparing Predictions of Two Radioecological Models with Measured Values

The models most widely used in France for impact studies related to nuclear facilities have been consolidated into computerized reference under the code name “DUNE”.The environmental effects of radionuclides released during the Chernobyl accident allowed observations to be made with applications not only to accidental fallout but also to routine waste discharge.Two examples are considered which reveal the difficulties encountered in completely verifying a model: one involves the contamination of mutton, and the other concerns radionuclide migration in soils.Two questions are then raised: “How can a model which produces uncertain results be confronted with field measurements which are variable by nature?” and “Should existing models be modified in the light of the latest observations?”