Transport Pathways of Radionuclides and Chemical Contaminants in the Kara Sea

A joint Norwegian/US field expedition to the Kara Sea was carried out in August-September 1995. The main purpose of the expedition was to monitor contamination levels in sea water and sediments, determine transport pathways of contaminants and investigate oceanographic circulation patterns. The results from this investigation corroborate earlier findings that 137 Cs and 90 Sr concentrations are not appreciably elevated above expected levels for the Kara Sea. Although the potential for sorption of 137 Cs and 90 Sr to sediments is greatest within the mixing zones of the rivers Ob and Yenisey, the observed distribution of 137 Cs and 90 Sr in the Kara Sea is primarily controlled by water mass transport processes. Influence of a 90 Sr contribution from the rivers has been detected in the Ob and Yenisey estuaries. The concentration levels of heavy metals is generally very low and the levels of PCBs were below the detection limit for all the measured samples.