No abstract available

[en] Application of nuclear reactions for military purposes and technical imperfection of nuclear power plants raised interest in formation of radioactive elements in these processes on one hand and their occurrence in environment on the other. ⁹⁰Sr, (β-emitter), belongs to isotopes of high radiotoxicity due to its good assimilation by organisms and long half-life time as well as biological half-life. Respective data are presented in Table 1. Because of radiochemical properties of ⁹⁰Sr, analysis of its concentration is very difficult. The whole process comprises laborious stages: isolation of the isotope from the sample, removing contamination, elimination of the decay product (⁹⁰Y) and radioactivity measurement. Many analytical methods have been presented in literature for years. Generally, one can divide them in two groups: fast and standard. Fast methods, (from several hours to a few days) are mostly applied to fresh samples (immediately after radioactive fall-out) containing ⁸⁹Sr and ⁹¹Y beside ⁹⁰Sr and ⁹⁰Y. Despite smaller accuracy they can provide information on possible danger. More credible data may be obtained from .old. samples (2-3 years from contamination) by standard methods. The mostly encountered analytical problems are: sample dissolution, removal of calcium and iron ions, removing primary/parental isotopes of radium, thorium, actinium and lead. Methods for ⁹⁰Sr-⁹⁰Y separation (liquid-liquid and solid-liquid extraction) are well known and broadly presented in literature. Those methods used to determine concentration of radioactive ⁹⁰Sr in environmental samples. A skilled radioanalyst may modify them according to the needed procedure, which is described in present paper. (author)

[en] Here are presented results of studies on vertical and horizontal migration of strontium ⁹⁰Sr isotope in soil systems of Bug river valleys. Mean radioactivity of strontium in these soils was 26.15 ± 22.2 Bq/kg. Atmospheric precipitation of strontium on this area was 0.35 kBq/m2/cm. Radioactivity in soil profiles ranged from 17 to 130 Bq/m2/cm and the isotope was detected even at 30 cm depth. Some tendency to vertical migration of strontium towards the river was noticed. Obtained results were compared with concentrations of calcium and strontium in the soil. Any clear influence of these elements on the migration of strontium ⁹⁰Sr was noticed. (author)

[en] This paper takes a project manager's perspective and discusses the role of the quality assurance organization in the development, implementation and interface related to the QA program for waste projects. The author describes the role which the QA program plays in allowing project management to assure that the project manager knows what is placed in the repository and the characteristics of the surrounding environment meet closure requirements

[en] The concentration of gamma emitters in grass samples of central-eastern Poland have been determined. The transfer factors for Cs-137 were calculated for particular samples. The effects of soil type, location of the sampling points and of potassium concentration on this transfer factor were studied. (author). 16 refs, 3 figs, 1 tab

[en] Some results of the extraction of strontium and yttrium from soil samples by concentrated nitric acid are described. The concentration of Sr and Y in the solid was determined by XRF method. The results obtained allowed to elaborate the conditions of acid leaching and to propose an analytical procedure for the determination of ⁹⁰Sr in samples without their total dissolution. (author)

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No abstract available

[en] Research data on concentration and transportation of ⁹⁰Sr in cultivate soils and its migration in undisturbed from Leczna-Wlodawa Lake District are presented. ⁹⁰Sr analysis was based on yttrium path. A special attention was paid to the precision in excluding of Th and U radioisotopes and their daughters using solid-liquid extraction (on Dovex ionite), and Pb by PbI₂ precipitation. The obtained results revealed various contamination of studied soils by ⁹⁰Sr although its concentration did not exceed 10 Bq/kg in the most samples. The highest concentration was noticed in upper 20 cm layers in both types of soils. Vertical migration rate of ⁹⁰Sr, calculated from compartment model, was below 1 cm/yr for the most researched soils. (author)

[en] Results of studies of Na⁺, K⁺ and Cs⁺ influence on the adsorption of ⁸⁵Sr on soil samples of the different types of successive horizons are presented. It was proved that the adsorption isotherms in log-log coordinates are of straight-line type and may be described by the Freundlich equation. Monovalent cations influence the coverage degree of the soil surface by ⁸⁵Sr (most often lowering it) in the following order K⁺ ≥ Na⁺ ≥ Cs⁺. The investigation of pH influence proved its essential meaning in the process. The plateau of surface coverage degree versus pH lies above pH 5.5 or 6.5 depending on the soil type. Generally, in the studied system, the size of ⁸⁵Sr adsorption depends on the concentration of the isotope, pH of the solution, type of monovalent cation, and on the soil properties. (author)