In order to evaluate consequences of deposited radioactive cesium (and other radioactive substances) in natural systems a GIS based model called Stratos has been developed. This model incorporates information regarding deposition, transfer to vegetation and animals, intervention levels and geographical distribution of animals. The presentation will use a case study which describes the possible environmental consequences for Norway due to a hypothetical accident at the Sellafield complex in the UK. The scenario considered involves an explosion and fire at the B215 facility resulting in a 1 % release of the total HAL 1 inventory of radioactive waste with a subsequent air transport and deposition in Norway. Air transport modeling is based on real meteorological data from October 2008 with wind direction towards Norway and heavy precipitation. This weather is considered to be quite representative as typical seasonal weather. Based on this weather scenario, the estimated fallout in Norway will be ~17 PBq of cesium-137 which is 7 times higher than fallout after the Chernobyl accident. The modeled radioactive contamination is linked with data on transfer to the food chain and statistics on production and hunting to assess the consequences for foodstuffs. The investigation has been limited to the terrestrial environment, focusing on wild berries, fungi, and animals grazing unimproved pastures (i.e. various types of game, reindeer, sheep and goats). The results of a model-run are maps for the chosen products, with categorized colors - giving the degree of consequences. A linked text file gives relevant numeric values for each color. The Stratos model is written in python which calls GRASS-functions and uses as gui for model setup. The model has been used for two reports at the Norwegian Radiation Protection Authority, and is currently being used and developed further in the "Centre for Environmental Radioactivity" (CERAD), cerad.nmbu.no.