Rapport Technique NTB 87-11

Programme suisse de recherches et de surveillance du site d'immersion de déchets radioactifs en Atlantique Nord-EstProgramme «PROSPER», Rapport final

This report presents the final results from the activities of the PROSPER group during the first phase (1981 – 1986) of CRESP (Coordinated Research and Environmental Surveillance Programme) which was coordinated by the Nuclear Energy Agency of the DECO. The first two chapters outline the legal and historical framework of deep-sea dumping as a disposal option for radioactive wastes. The internationally coordinated research and surveillance programme at the disposal site in the NE Atlantic is described in chapter 3, while chapter 4 is dedicated to the Swiss contribution to the project, together with a resumé of the most significant results obtained between 1982 and 1986. The research carried out by the PROSPER group relates to characterisation of the hydrological and nepheloid features at the disposal site, the geochemistry of the sediments and suspended materials and the bacterial activity in the sediments. New information has been obtained on the nepheloid zones which can be disturbed by deep ocean currents. The geochemical studies of the sediments have allowed the sedimentation and accumulation rates at the dumping site to be quantified. These results were integrated into the review of the suitability of the site carried out by the NEA/OECD in 1985.