Isotopic Disequilibrium for Assessment of Radionuclide Transport in Peat Lands : Uranium-Thorium Series Nuclides in a Core from Klarebäcksmossen, Oskarshamn, Sweden

摘要: In order to assess the risks that are associated with a deep repository of nuclear waste, it is important know how different radionuclides behave in environments. Since some most critical waste such as Ra-226 occur naturally environment, possible study their behaviour directly. Peat lands thought be one ecosystems due capability accumulating large amounts radioactivity and exposure pathways man. Klarebacksmossen peat land situated close power plant Oskarshamn, which two areas Sweden where site investigations for future being conducted. this complete peat-gyttja-clay profile from has been analysed number both natural artificial using gamma spectrometry. The degree isotopic disequilibrium between nuclides uranium-thorium series used radionuclide migration accumulation throughout core. measurements indicate uranium accumulated gyttja, but mobilised clay. Radium, on other hand, leached gyttja layers, strikingly low Ra-226/Pb-210 ratios show might have very recently. Alternatively, there extensive Rn-222. levels were found radionuclides, clear differences minerotrophic ombrotrophic peat. This may uptake by mainly passive. rate also determined Pb-210 dating.