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To satisfy the increasing number of directives referring to the control of radioactivity and radioprotection,numerous analytical methods and conditioning processes for radioactive waste have been developed.This presentation is a summary of different studies realized in Radiochemical Laboratory (Faculty of Sciences,University Hassan Ⅱ Mohammedia-Casablanca) concerning different operational methods of analysis,measures,removal and storage of the radioelements.Two objectives were fixed; the first is the understanding of the transfer mechanisms of radioelements at the solid/liquid interfaces,the second is the search for the materials for the adsorption and the storage of the radioelements.As the first goal,the proposed methods have been applied for U,Th and some of their respective daughter's determination in the sedimentary rock: phosphate,black shale,coastal of Paleozoic and Mesozoic sedimentary rocks (Basalts,evaporates,carbonates,shale and sandstones).Radiochemical methods developed were used also to study the geochemistry of mainly U,Th in these different sedimentary rocks and in marine water and sediment samples.Mostly,the distribution of U in the different phases was carried out by sequential extraction and the isotopic ratios were determined.As for the second goal,the adsorbent materials of radionuclides have been produced from Moroccan oil shale through different procedures.One of these procedures is based on the activation of various fractions,obtained from the raw rock,by impregnation in KMn04 solution.The best results were obtained by the activation of the oil shale after pyrolysis at 550℃ in air; the elimination of radionuclides from standard solutions was almost total.Another procedure aims at ameliorating the textural and structural properties of adsorbents by chemical activation.Two activated agents,sulfuric and phosphoric acid were used in this procedure for the activation of the decarbonated raw rock.The adsorbents showed good properties; a specific area equals 270 m2.g-1 and 600 m2·g-1 for the adsorbent obtained by sulphuric acid and phosphoric acid respectively.In addition,important surface functions were developed.The results of the adsorption tests have shown a high affinity of these adsorbents facing radionuclides U and Th.Considering its great adsorption capacity,the abundance of raw material in Morocco and the simplicity of the production process,the adsorbents prepared from oil shale can be used efficiently for the treatment of liquid radioactive waste and the storage of many radioelements.