This book is a collection of papers given on the first day of the international symposium Radionuclides in the Oceans (RADOC 96-97). This symposium was organized by the Nuclear Safety and Protection Institute (irsn) and the Ministry of Agriculture, Fisheries and Food (MAFF). It was divided into two parts. The first part, « Inventories, Behaviour and Processes », took place at Octeville?Cherbourg, France (7-11 October 1996) and dealt with the same themes as the 1987 Cherbourg symposium (Radionuclides as a tool for oceanography) and the 1991 Norwich symposium (Radionuclides in the study of marine processes). The second part, « Impacts on Man and the environment », will take place at Norwich and Lowestoft (7-11 April 1997), and will cover the themes of radiological and environmental protection and modelling.
Ten years after Chernobyl, after the French decision to end nuclear weapon testing in the Pacific Ocean, after the end of the OECD-NEA Coordinated Research and Environmental Surveillance Programme related to low-level waste dumping in deep sea, and one hundred years after the discovery of radioactivity, irsn has considered it useful to assemble the available information on artificial radioactivity levels in the seas and oceans. The objective is to address scientific and public concerns about the use of the sea as a « waste repository », and to answer regarding the radioactive contamination of the seas and oceans. Therefore, international experts have been invited to describe and quantify, during the first day of the symposium (Part 1), the inputs and inventories of artificial radionuclides released in seas and oceans by civil and military activities.
In the different chapters of this book, radionuclides are studied in geographical areas of different size, and varying physical and biological features. Therefore, some presentations deal with oceans taken as a whole (Atlantic, Pacific and Indian oceans). Some sources of radionuclides, such as atmospheric fallout, both before and after Chernobyl, have a large scale impact, whereas others, such as marine dumping sites, sites for nuclear weapon tests, and damaged submarines provide more localised inputs of artificial radionuclides.
Others presentations focus on of particular interest seas from the point of view of specific radionuclide sources and the particular processes which govern radionuclide behaviour. The Channel, the North Sea and the Irish Sea are quite shallow and receive, directly or indirectly a small fraction of the wastes released by reprocessing plant wastes. The Baltic Sea has been strongly affected by Chernobyl, and is subject to a high salinity pressure gradient. The Black Sea has also been marked by Chernobyl and is s1trongly anoxic. The Mediterranean Sea receives an input of radionuclides from the Rhone River outflow into the western basin and has exchanges with the Atlantic Ocean. Dumped radioactive wastes, radionuclide inputs from the Ob and Yenisei river basins, radionuclides from European reprocessing plants transported by ocean currents, and radionuclide transport by ice must be considered in the Arctic, Barents, Kara and Laptev Seas.
It appears that such a comprehensive review of all the available data has not been made in recent years and it is the aim of this book to provide it.
The production of this book was made possible by the collaborative efforts of the international experts in providing, within a tight schedule, the inputs requested by irsn; they deserve our gratitude.
We are very grateful to the Minister of the Environment, Mrs Corinne Lepage, who has accepted to open the session devoted to inputs and inventories of radionuclides in seas and oceans.