The Behaviour of Radionuclides in the Irish Sea

摘要

Authorised releases of low-level radioactive liquid wastes have been made to the NE Irish Sea from the nuclear fuel reprocessing plant at Sellafield for almost 50 years. The radionuclide content of the effluent has varied over time in response to fuel throughput and changes in the waste management plant installed on the site. This paper briefly considers three components of the waste. For ~(137)Cs and ~(239)Pu+~(240)Pu, the annual inputs for 1997 were about 0.2% of the peak values prevailing in the early to mid-1970s; in the period 1994-1997, the annual inputs of ~(99)Tc were 20-40 times greater than during the previous decade. The decay-corrected environmental inventories of ~(99)Tc, ~(137)Cs and ~(239)Pu+~(240)Pu in December 1995 were 600, 26500 and 590 TBq, respectively. Due to their varying chemical nature, the three elements might be expected to behave somewhat differently in the sea.