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Sourabie DG, Hebert D, Benedetti L, Vitorge E, Lourino-Cabana B, Guillou V, Maro D. First quantitative constraints on chlorine 36 dry deposition velocities on grassland: Comparing measurements and modelling results. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 268-269:107264. [PMID: 37572511 DOI: 10.1016/j.jenvrad.2023.107264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/14/2023]
Abstract
Once released into the atmosphere, radionuclide dry deposition represents a major transfer process. It can be accurately characterized by its deposition velocity. However, this parameter is poorly constrained for most radionuclides, including chlorine 36. Chlorine 36 is a radionuclide of cosmogenic and anthropogenic origin. It may be discharged into the environment as gases and/or particles during the decommissioning of nuclear plants and the recycling of nuclear fuels. In this study, chlorine 36 deposition velocities are, for the first time, experimentally determined on grass downwind from the Orano La-Hague plant. The atmospheric chlorine 36 measurements were on average 50 nBq.m-3 for the gaseous fraction and 19 nBq.m3 for the particulate fraction. To measure the chlorine 36 transferred from the atmosphere to the grass, a method was devised for extracting the chlorides contained in solid matrices. With this method, chlorides were extracted with a mean efficiency of 83%. Chlorine 36 concentrations in the grass were on average 4 μBq.g-1, suggesting fast uptake of atmospheric chlorine 36. The yielded 36Cl dry deposition velocities varied with the season and were between 1 × 10-3 and 6 × 10-3 m s-1. The chlorine 36 depositions were modelled by adapting the existing deposition models and based on meteorological and micro-meteorological data. The dry deposition velocities calculated by the model showed less than one order of magnitude of difference with those determined experimentally. The deposition fluxes calculated by the model showed that the atmospheric depositions were predominantly gaseous chlorine 36 (>97%). However, on remote sites, the particulate fraction could be larger and have a greater influence on dry deposition. As chlorine 36 is a highly soluble and bioavailable element, these results will enable a better study of its behaviour in the environment and a more accurate evaluation of its dosimetric impact.
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Affiliation(s)
- Deo-Gratias Sourabie
- Institute for Radioprotection and Nuclear Safety (IRSN), PSE-ENV/SRTE/LRC, Cherbourg-Octeville, 50130, France; Univ. Aix-Marseille, CNRS, IRD, INRAE, Coll. France, UM 34 CEREGE, Aix-en-Provence, 13545, France.
| | - Didier Hebert
- Institute for Radioprotection and Nuclear Safety (IRSN), PSE-ENV/SRTE/LRC, Cherbourg-Octeville, 50130, France.
| | - Lucilla Benedetti
- Univ. Aix-Marseille, CNRS, IRD, INRAE, Coll. France, UM 34 CEREGE, Aix-en-Provence, 13545, France.
| | - Elsa Vitorge
- EDF - DPNT - DIPDE - DEE - Environment Department, Villeurbanne, 69100, France.
| | - Beatriz Lourino-Cabana
- EDF R&D LNHE - National Laboratory of Hydraulics and Environment, Chatou, 78401, France.
| | - Valery Guillou
- Univ. Aix-Marseille, CNRS, IRD, INRAE, Coll. France, UM 34 CEREGE, Aix-en-Provence, 13545, France.
| | - Denis Maro
- Institute for Radioprotection and Nuclear Safety (IRSN), PSE-ENV/SRTE/LRC, Cherbourg-Octeville, 50130, France.
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Radiological Impact Assessment for hypothetical accident scenarios of a proposed pressurized water reactor using HotSpot code. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Investigation of a Gaussian Plume in the Vicinity of an Urban Cyclotron Using Helium as a Tracer Gas. ATMOSPHERE 2022. [DOI: 10.3390/atmos13081223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Studies focusing on the radiological impact of fluorine 18 on populations living near to cyclotrons (<200 m) frequently assume normal distribution of atmospheric concentration for simplification purposes. On this basis, Gaussian models are used, despite their limits, as deployment requires little input data and computing resources. To estimate the ability of a Gaussian model to predict atmospheric dispersion in an urban environment, we used helium as a new passive tracer of atmospheric dispersion in the near-field range (<500 m) of the Beuvry hospital cyclotron (France). The atmospheric transfer coefficients measured in the field were compared with those modeled using a Gaussian equation. According to the results, helium is an effective tracer of atmospheric dispersion when attempting to determine atmospheric transfer coefficients ( downwind of a discharge point. The Briggs-rural, Briggs-urban and Doury Gaussian models underestimate and sometimes maximum in the prevailing weather conditions during the experiments. By compiling the results of this study with data from the literature, it appears that the maximum observed obey a power law as a function of the distance from the discharge point, for distances from the discharge point in excess of 20 m.
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Pittet PA, Josset M, Boilley D, Bernollin A, Rougier G, Froidevaux P. Origin and age of an ongoing radioactive contamination of soils near La hague reprocessing plant based on 239+240Pu/ 238Pu and 241Am/ 241Pu current ratios and 90Sr and Ln(III) soil contents. CHEMOSPHERE 2021; 270:129332. [PMID: 33422999 DOI: 10.1016/j.chemosphere.2020.129332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 12/10/2020] [Accepted: 12/13/2020] [Indexed: 06/12/2023]
Abstract
Nuclear reprocessing plants are sources of environmental contamination by gaseous or liquid discharges. Numerous radionuclides are of concern, with actinides and 90Sr being the most radiotoxic. Environmental radioactivity survey programs mostly use γ-spectrometry to track contaminations because γ-spectrometry is very cost effective and can be carried out on raw samples. On the other hand, the determination of β- or α-emitting radionuclides in environmental samples requires rather sophisticated analytical methods, and are thus dedicated to specific goals. However, measuring radionuclides such as Pu, Am, and Sr often provides more information about the presence of a current or prior contamination and on its origin, based on the isotopic composition of the samples. We found that the analysis of 241Pu, 239+240Pu, 241Am, and 90Sr of a few selected soil samples taken near the nuclear reprocessing plant of La Hague, France, revealed the presence of a previous environmental contamination originating from several incidents in La Hague site involving atmospheric transfer and leaks in flooded waste pits. The 241Am-241Pu dating method indicated a contamination period prior to 1983. The presence of elevated levels of light non-radioactive lanthanides and yttrium in the soil samples confirmed the involvement of cold fuel. Our results demonstrate how long-lived actinides are likely to reveal a long-term contamination of the environment by spent fuel. Our study indicates that there is a requirement to use more sophisticated tools than γ-spectrometry when surveying the environments surrounding industrial plants for nuclear power and nuclear reprocessing with a potential for the accidental release of radioactivity into the environment.
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Affiliation(s)
- Pierre-André Pittet
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Mylène Josset
- ACRO, Association pour le Contrôle de La Radioactivité Dans L'Ouest, 138, Rue de L'Eglise, 14200, Hérouville St Clair, France
| | - David Boilley
- ACRO, Association pour le Contrôle de La Radioactivité Dans L'Ouest, 138, Rue de L'Eglise, 14200, Hérouville St Clair, France
| | - Antoine Bernollin
- ACRO, Association pour le Contrôle de La Radioactivité Dans L'Ouest, 138, Rue de L'Eglise, 14200, Hérouville St Clair, France
| | - Guillaume Rougier
- ACRO, Association pour le Contrôle de La Radioactivité Dans L'Ouest, 138, Rue de L'Eglise, 14200, Hérouville St Clair, France
| | - Pascal Froidevaux
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
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Bollhöfer A, Schlosser C, Schmid S, Konrad M, Purtschert R, Krais R. Half a century of Krypton-85 activity concentration measured in air over Central Europe: Trends and relevance for dating young groundwater. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 205-206:7-16. [PMID: 31082675 DOI: 10.1016/j.jenvrad.2019.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/26/2019] [Accepted: 04/27/2019] [Indexed: 06/09/2023]
Abstract
For almost half a century weekly samples for the measurement of krypton-85 (85Kr) activity concentrations in surface air have been collected by the Bundesamt für Strahlenschutz (BfS), Germany. Sampling started at Freiburg (230m asl) in 1973, Mt Schauinsland (1205m asl) in 1976 and Mt Jungfraujoch in Switzerland (3454 asl) in 1990. Distinct maxima in the time series of atmospheric 85Kr activity concentration are caused by emissions from nuclear reprocessing plants in Europe, mainly the La Hague, France, and Sellafield, UK, reprocessing plants. Between 1970 and 1990 peak activity concentrations measured in winter along the Rhine Rift in Freiburg are often higher than at Mt Schauinsland, due to emissions from the operating pilot reprocessing plant in Karlsruhe - approximately 130 km to the north - and large-scale inversions that inhibit exchange of air masses within the Rhine Rift with those at higher altitudes. From the early 1990s onwards, after the shut-down of the pilot plant, differences between Freiburg and Schauinsland are much smaller. Activity concentrations measured at Jungfraujoch are generally lower and close to baseline levels, due to its location in the free troposphere. Weekly baseline and average 85Kr activity concentration in the atmosphere in Central Europe were modelled from almost 12,000 individual measurements at 11 stations. The baseline and average have continuously increased, interrupted by a relatively stable period between 2009 and the end of 2014 with a baseline activity concentration of about 1.39 Bq/m3. Depending on the geographical location and hydrological conditions, the modelled baseline or average 85Kr activity concentration time series can be used as input functions for the dating of young groundwater.
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Affiliation(s)
| | | | - Sabine Schmid
- Bundesamt für Strahlenschutz, 79098, Freiburg, Germany
| | | | | | - Roman Krais
- Bundesamt für Strahlenschutz, 79098, Freiburg, Germany
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Connan O, Hébert D, Solier L, Maro D, Pellerin G, Voiseux C, Lamotte M, Laguionie P. Atmospheric tritium concentrations under influence of AREVA NC La Hague reprocessing plant (France) and background levels. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 177:184-193. [PMID: 28689161 DOI: 10.1016/j.jenvrad.2017.06.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/15/2017] [Accepted: 06/18/2017] [Indexed: 06/07/2023]
Abstract
In-air tritium measurements were conducted around the AREVA NC La Hague reprocessing plant, as well as on other sites that are not impacted by the nuclear industry in northwest of France. The results indicate that the dominant tritium form around the AREVA site is HT (86%). HT and HTO levels are lower than 5 and 1 Bq. m-3 for hourly samples taken in the plume. No tritiated organic molecules (TOM) were detected. 26 measurement campaigns were performed and links were established between near-field 85Kr, HT and HTO activities. Environmental measurements are in line with those taken at the discharge stack, and tend to demonstrate that there are no rapid changes in the tritium forms released. Out of the influence of any nuclear activities, the levels measured were below 13 mBq.m-3 for HT and 5 mBq.m-3 for HTO (<0.5 Bq. L-1). HTO level in air seems to be influenced by HTO activities in surrounding seawater.
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Affiliation(s)
- O Connan
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France.
| | - D Hébert
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France
| | - L Solier
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France
| | - D Maro
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France
| | - G Pellerin
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France
| | - C Voiseux
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France
| | - M Lamotte
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France
| | - P Laguionie
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LRC, Radioecology Laboratory, BP10, Rue Max Pol Fouchet, 50130 Cherbourg-Octeville, France
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Lavielle B, Thomas B, Gilabert E, Canchel G, Horlait D, Topin S, Pointurier F, Moulin C. Development toward a double focusing isotopic separator for noble gas isotope enrichment. JOURNAL OF MASS SPECTROMETRY : JMS 2016; 51:908-913. [PMID: 27747992 DOI: 10.1002/jms.3800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 05/31/2016] [Accepted: 06/17/2016] [Indexed: 06/06/2023]
Abstract
A double focusing sector field mass filter used in Nier-Johnson geometry has been built in order to perform Kr isotope enrichment for 81 Kr and 85 Kr isotopes. The principle consists in implanting Kr+ ions accelerated at 7 keV in Al foils after separation using the magnetic sector. A specific ion source has been designed capable of generating high Kr+ ion beams (>0.5 μA) to transfer into the collecting Al foils in 3 to 5 h significant fractions of large Kr samples (1015 to 1016 atoms) initially introduced in the instrument. Implanted Kr isotopes can be further selectively released from the Al foil by surface ablation using an infrared laser beam. Implantation yields and enrichment factors are measured using a conventional mass spectrometer. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Bernard Lavielle
- University of Bordeaux, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, , 19 Chemin du Solarium, 33175, Gradignan Cedex, France.
- CNRS, IN2P3, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, 19 Chemin du Solarium, 33175, Gradignan Cedex, France.
| | - Bertrand Thomas
- University of Bordeaux, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, , 19 Chemin du Solarium, 33175, Gradignan Cedex, France
- CNRS, IN2P3, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, 19 Chemin du Solarium, 33175, Gradignan Cedex, France
| | - Eric Gilabert
- University of Bordeaux, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, , 19 Chemin du Solarium, 33175, Gradignan Cedex, France
- CNRS, IN2P3, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, 19 Chemin du Solarium, 33175, Gradignan Cedex, France
| | - Gregory Canchel
- University of Bordeaux, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, , 19 Chemin du Solarium, 33175, Gradignan Cedex, France
- CNRS, IN2P3, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, 19 Chemin du Solarium, 33175, Gradignan Cedex, France
| | - Denis Horlait
- University of Bordeaux, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, , 19 Chemin du Solarium, 33175, Gradignan Cedex, France
- CNRS, IN2P3, Centre d'Etudes Nucléaires de Bordeaux-Gradignan, 19 Chemin du Solarium, 33175, Gradignan Cedex, France
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