The Palmottu analogue project

The report presents a comprehensive summary of the results of investigations carried out during 1988-1991 at the Palmottu natural analogue study site. A small U-Th mineralization in Nummi-Pusula, southwestern Finland. In the studies information has been sought concerning radionuclide mobilization and transport phenomena analogues to those assumed to apply to repository near- and far-field phenomena. A major effort has been directed towards the geological and hydrogeological characterization of the Palmottu area. Detailed information on the regional and local structural geology in three dimensions has been obtained. Observations concerning uranium sorption and rock matrix diffusion have been made. Detailed information about uranium fixation mechanisms has been obtained, rendering certain interpretation about uranium mobility at Palmottu. Element mobility has also been studied using the multielement profile approach. Studies for finding and characterizing groundwater colloids have been performed. Studies dealing with the biospheric transport of radionuclides have also been initiated for establishing background data. As a conclusion of the 4-year study period an analysis of progress through the various stages of the study is also given. .000: INIS