Long-term consequences for Northern Norway of a hypothetical release from the Kola nuclear power plant

The spatial and temporal variation in radiocaesium and 90Sr doses to two population groups of the two Northernmost counties of Norway, Troms and Finnmark, following a hypothetical accident at the Kola nuclear power plant (KNPP) have been estimated using a model implemented within a geographical information system. The hypothetical accident assumes a severe loss of coolant accident at the KNPP coincident with meteorological conditions causing significant radionuclide deposition in the two counties. External doses are estimated from ground deposition and the behaviour of the different population groups, and internal doses from predicted food product activity concentrations and dietary consumption data. Doses are predicted for reindeer keepers and other Norwegian inhabitants, taking account of existing 137Cs and 90Sr deposition but not including the remedial effect of any countermeasures that might be used. The predicted doses, arising mainly from radiocaesium, confirm the Arctic Monitoring and Assessment Programme assessment that residents of the Arctic are particularly vulnerable to radiocaesium contamination, which could persist for many years. External doses are predicted to be negligible compared to ingestion doses. Ingestion doses for reindeer keepers are predicted to exceed 1 mSv y−1 for several decades primarily due to their high consumption of reindeer meat. Other Norwegians would also be potentially exposed to doses exceeding 1 mSv y−1 for several years, especially if they consume many local products. Whilst reindeer production is the most important exposure pathway, freshwater fish, lamb meat, dairy products, mushrooms and berries are also significant contributors to predicted ingestion doses. Radionuclide fluxes, defined as the total output of radioactivity in food from an area for a unit time, are dominated by reindeer meat. The results show the need for an effective emergency response, with appropriate countermeasures, should an accident of the scale considered in this paper occur at the KNPP.