Radionuclides in the Kongsfjorden area, Svalbard

¹ Norwegian Radiation Protection Authority, Environmental Protection Unit, Polar Environmental Centre, 9296 Tromso, Norway
² Norwegian Radiation Protection Authority, P.O. Box 55, 1332 Osteras, Norway

Abstract

The archipelago of Svalbard is located at the junction of Arctic Ocean, the North Atlantic and the Barents Sea. During a field campaign in May 2000, seawater, sea ice and seaweed, were collected in Kongsfjorden at the western coast of Spitsbergen. Possible sources for artificial radionuclides in the marine Svalbard environment are long-distance transported discharges from nuclear reprocessing plants, dumped radioactive waste, accidents with ships, submarines and power plants containing radioactive material, and global fallout from nuclear test explosions. Samples were taken to measure the radioisotopes technetium (⁹⁹Tc, sea water and seaweed), plutonium (sea water) and caesium (¹³⁷Cs, sea water and melted sea ice). Certain processes are unique for the high-arctic environment such as formation of sea ice. The fast ice in Kongsfjorden provides an opportunity to investigate to what degree radionuclides accumulate in sea ice compared with the seawater below. Another important question relates to how radionuclides accumulate in the Arctic in different types of seaweed. First results from laboratory analyses of the samples taken in May 2000 show ⁹⁹Tc concentrations in seawater similar to levels measured in the western Barents Sea in 1999-2000. Corresponding measurements along the Norwegian coast are one order of magnitude higher. Enhanced values measured at Hillesøy (Northern Norway), in the Barents Sea and off Svalbard and can be explained with increased discharges of ⁹⁹Tc-contaminated wastewater at the Sellafield reprocessing plant since 1994.