Migration ability of radionuclides in soil-vegetation cover of Belarus after Chernobyl accident

Title: Migration ability of radionuclides in soil-vegetation cover of Belarus after Chernobyl accident

Author: G.A. Sokolik, T.G. Ivanova, S.L. Leinova, S.V. Ovsiannikova, I.M. Kimlenko

Reference: Environment International, Volume 26, Issue 3, January 2001, Pages 183-187

DOI: http://dx.doi.org/10.1016/S0160-4120(00)00104-5

Keywords: Radionuclides; Cesium-137; Strontium-90; Plutonium-239, 240; Americium-241; “hot” particles; Physicochemical State; Chernobyl accident; Migration parameters; Biological accessibility

Abstract: This paper illustrates the experimental experience achieved in the research of the self-restoration of radioactive-contaminated natural ecosystems. The main directions of studies were: the content and geochemical stability of “hot” particles in radioactive fallout from Chernobyl accident; the physicochemical forms (water-soluble, exchangeable, mobile and fixed) of Cs-137, Sr-90, Pu-239, 240 and Am-241 in the wide varieties of soils; the biological accessibility of radionuclides and their contents in soil pore solutions; and the dynamics and migration parameters of radionuclides vertical redistribution in different landscape conditions.

URL: http://www.sciencedirect.com/science/article/pii/S0160412000001045

α-Particle track investigation of the Chernobyl Nuclear Power Plant accident region soil samples

Title: α-Particle track investigation of the Chernobyl Nuclear Power Plant accident region soil samples

Author: L.L. Kashkarov, G.V. Kalinina, V.P. Perelygin

Reference: Radiation Measurements, Volume 36, Issues 1–6, June 2003, Pages 529-532

DOI: http://dx.doi.org/10.1016/S1350-4487(03)00199-9

Keywords: α Tracks; CZ plastic track detector; Highly-radioactive “hot” particles; Chernobyl accident region; Radio-nuclide soil contamination

Abstract: Results of α-particle track studies (Radiat. Meas. 25(1–4) (1995) 413; Radionuclides and Heavy metals in Environment, Vol. 5, 2001, Kluwer Academic Publisher, Dordrecht) indicate that the surface layer of the soil in the Chernobyl Nuclear Power Plant (NPP) accident region consists of thinly dispersed radionuclides and highly-radioactive “hot” particles (HPs). The latter contain nearly 2/3rds of the total α-activity of the contaminated soil. In the present report, the new results of continued HP α-activity characteristics are presented. The chief attempt made was to investigate size–frequency vs. α-activity distribution of HPs of size fraction ⩽10– . For the Hp-aggregates with ∼100– sizes, α-radio-nuclide heterogeneity was established. This is probably the result of formation of HP-aggregates during the second stage of the NPP accident process: in these HPs the presence of not only U and fission products of “fuel” origin has been revealed, but also of terrestrial matter components.

URL: http://www.sciencedirect.com/science/article/pii/S1350448703001999

Resuspension of coarse fuel hot particles in the Chernobyl area

Title: Resuspension of coarse fuel hot particles in the Chernobyl area

Author: Florian Wagenpfeil, Jochen Tschiersch

Reference: Journal of Environmental Radioactivity, Volume 52, Issue 1, January 2001, Pages 5-16

DOI: http://dx.doi.org/10.1016/S0265-931X(00)00081-3

Keywords: Resuspension; Chernobyl fallout; Hot particles; Aerosol sampler; Digital autoradiography

Abstract: Measurements of resuspended aerosol in the Chernobyl 30-km exclusion zone have shown coarse fuel hot particles in the activity range 1–12 Bq per particle. The particles were sampled with newly designed rotating arm impactors which simultaneously collect during the same experiment three samples with fuel particles in the size ranges larger than 3 μm, larger than 6 μm and larger than 9 μm in geometric diameter. The radionuclide ratios, determined after γ-spectrometry, were in good agreement with the theoretical calculations for the radionuclide-composition of the Chernobyl Nuclear Power Plant at the moment of the accident and the measured hot particles in soil in the early years after the accident. The number concentrations of airborne hot particles were derived from digital autoradiography. For wind resuspension, maximal concentrations of 2.6 coarse hot particles per 1000 m³ and during agricultural activities 36 coarse hot particles per 1000 m³ were measured. The geometric diameter of single hot particles was estimated to be between 6 and 12 μm.

URL: http://www.sciencedirect.com/science/article/pii/S0265931X00000813

Classification of hot particles from the Chernobyl accident and nuclear weapons detonations by non-destructive methods

Keywords: Hot particles; Chernobyl; Weapons tests; Fallout; Characterisation; Analysis

Abstract: Both after the Chernobyl accident and nuclear weapon detonations, agglomerates of radioactive material, so-called hot particles, were released or formed which show a behaviour in the environment quite different from the activity released in gaseous or aerosol form. The differences in their characteristic properties, in the radionuclide composition and the uranium and actinide contents are described in detail for these particles. While nuclear bomb hot particles (both from fission and fusion bombs) incorporate well detectable trace amounts of ⁶⁰Co and ¹⁵²Eu, these radionuclides are absent in Chernobyl hot particles. In contrast, Chernobyl hot particles contain ¹²⁵Sb and ¹⁴⁴Ce which are absent in atomic bomb HPs. Obvious differences are also observable between fusion and fission bombs’ hot particles (significant differences in ¹⁵²Eu/¹⁵⁵Eu, ¹⁵⁴Eu/¹⁵⁵Eu and ²³⁸Pu/²³⁹Pu ratios) which facilitate the identification of HPs of unknown provensence. The ratio of ²³⁹Pu/²⁴⁰Pu in Chernobyl hot particles could be determined by a non-destructive method at 1 : 1.5. A non-destructive method to determine the content of non-radioactive elements by Kα-emission measurements was developed by which inactive Zr, Nb, Fe and Ni could be verified in the particles.

URL: http://www.sciencedirect.com/science/article/pii/S0265931X01000133

Resuspension of coarse fuel hot particles in the Chernobyl area

Title: Resuspension of coarse fuel hot particles in the Chernobyl area

Author: Wagenpfeil, Florian / Tschiersch, Jochen

Reference: Journal of Environmental Radioactivity, 52 (1), p.5-16, Jan 2001

doi: 10.1016/S0265-931X(00)00081-3

Keywords: Resuspension; Chernobyl fallout; Hot particles; Aerosol sampler; Digital autoradiography

Abstract: Measurements of resuspended aerosol in the Chernobyl 30-km exclusion zone have shown coarse fuel hot particles in the activity range 1–12 Bq per particle. The particles were sampled with newly designed rotating arm impactors which simultaneously collect during the same experiment three samples with fuel particles in the size ranges larger than 3 μm, larger than 6 μm and larger than 9 μm in geometric diameter. The radionuclide ratios, determined after γ-spectrometry, were in good agreement with the theoretical calculations for the radionuclide-composition of the Chernobyl Nuclear Power Plant at the moment of the accident and the measured hot particles in soil in the early years after the accident. The number concentrations of airborne hot particles were derived from digital autoradiography. For wind resuspension, maximal concentrations of 2.6 coarse hot particles per 1000 m³ and during agricultural activities 36 coarse hot particles per 1000 m³ were measured. The geometric diameter of single hot particles was estimated to be between 6 and 12 μm.

URL: http://www.sciencedirect.com/science/article/pii/S0265931X00000813

ASSESSMENT OF THE RADIONUCLIDE COMPOSITION OF “HOT PARTICLES” SAMPLED IN THE CHERNOBYL NUCLEAR POWER PLANT FOURTH REACTOR UNIT

Title: ASSESSMENT OF THE RADIONUCLIDE COMPOSITION OF “HOT PARTICLES” SAMPLED IN THE CHERNOBYL NUCLEAR POWER PLANT FOURTH REACTOR UNIT

Author: Farfan, E. / Jannik, T. / Marra, J.

Reference: HEALTH PHYSICS JOURNAL, Oct 2011

Keywords: 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; AMERICIUM; BURNUP; CESIUM; CESIUM ISOTOPES; CONFINEMENT; CURIUM; EUROPIUM; NUCLEAR POWER PLANTS; PLUTONIUM; RADIOISOTOPES; SHELTERS

Abstract: Fuel-containing materials sampled from within the Chernobyl Nuclear Power Plant (ChNPP) 4th Reactor Unit Confinement Shelter were spectroscopically studied for gamma and alpha content. Isotopic ratios for cesium, europium, plutonium, americium, and curium were identified and the fuel burnup in these samples was determined. A systematic deviation in the burnup values based on the cesium isotopes, in comparison with other radionuclides, was observed. The conducted studies were the first ever performed to demonstrate the presence of significant quantities of {sup 242}Cm and {sup 243}Cm. It was determined that there was a systematic underestimation of activities of transuranic radionuclides in fuel samples from inside of the ChNPP Confinement Shelter, starting from {sup 241}Am (and going higher), in comparison with the theoretical calculations.

URL: http://www.osti.gov/bridge/product.biblio.jsp?query_id=2&page=0&osti_id=1024191