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D. Hébert - One of the best experts on this subject based on the ideXlab platform.
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14C sources and distribution in the vicinity of La Hague Nuclear Reprocessing plant. Part I: Terrestrial environment
Radiocarbon, 2016Co-Authors: Michel Fontugne, Denis Maro, D. Hébert, Christine Hatté, Y. Baron, Eric DouvilleAbstract:COGEMA-La Hague Nuclear Reprocessing plant in the Cotentin Peninsula (northwest France) releases in the atmosphere about 19 TBq.yr (super -1) of radiocarbon. Three experiments in a terrestrial environment with sampling of a bio-indicator like furze were performed in 1997, 1998, and 1999, and additional air samples in the chimney plume were measured. Results presented here establish the (super 14) C distribution in the La Hague environment and suggest that a part of the (super 14) C content in the vegetation near the coast results from a (super 14) CO (sub 2) degassing of seawater supplied with the liquid waste from the Nuclear plant.
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comparison of rimpuff hysplit adms atmospheric dispersion model outputs using emergency response procedures with 85kr measurements made in the vicinity of Nuclear Reprocessing plant
Journal of Environmental Radioactivity, 2013Co-Authors: O Connan, Denis Maro, Kilian Smith, Catherine Organo, L Solier, D. HébertAbstract:Abstract The Institut de Radioprotection et de Surete Nucleaire (IRSN) performed a series of 85Kr air sampling campaigns at mesoscale distances (18–50 km) from the AREVA NC La Hague Nuclear Reprocessing plant (North West France) between 2007 and 2009. The samples were collected in order to test and optimise a technique to measure low krypton-85 (85Kr) air concentrations and to investigate the performance of three atmospheric dispersion models (RIMPUFF, HYSPLIT, and ADMS), This paper presents the 85Kr air concentrations measured at three sampling locations which varied from 2 to 8000 Bq m−3, along with the 85Kr air concentrations output by the dispersion models. The dispersion models made reasonable estimates of the mean concentrations of 85Kr field measurements during steady wind conditions. In contrast, the models failed to accurately predict peaks in 85Kr air concentration during periods of rapid and large changes in wind speed and/or wind direction. At distances where we made the comparisons (18–50 km), in all cases, the models underestimated the air concentration activities.
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Comparison of RIMPUFF, HYSPLIT, ADMS atmospheric dispersion model outputs, using emergency response procedures, with 85Kr measurements made in the vicinity of Nuclear Reprocessing plant
Journal of Environmental Radioactivity, 2013Co-Authors: O Connan, Denis Maro, Kilian Smith, Catherine Organo, L Solier, D. HébertAbstract:The Institut de Radioprotection et de Sureté Nucléaire (IRSN) performed a series of 85Kr air sampling campaigns at mesoscale distances (18-50km) from the AREVA NC La Hague Nuclear Reprocessing plant (North West France) between 2007 and 2009. The samples were collected in order to test and optimise a technique to measure low krypton-85 (85Kr) air concentrations and to investigate the performance of three atmospheric dispersion models (RIMPUFF, HYSPLIT, and ADMS),This paper presents the 85Kr air concentrations measured at three sampling locations which varied from 2 to 8000Bqm-3, along with the 85Kr air concentrations output by the dispersion models. The dispersion models made reasonable estimates of the mean concentrations of 85Kr field measurements during steady wind conditions. In contrast, the models failed to accurately predict peaks in 85Kr air concentration during periods of rapid and large changes in wind speed and/or wind direction. At distances where we made the comparisons (18-50km), in all cases, the models underestimated the air concentration activities. © 2013 Elsevier Ltd.
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Carbon 14 transfer from seawater to the atmosphere through degassing processes in the Bay of Seine (North-West of France)
Radioprotection, 2005Co-Authors: Michel Fontugne, Pascale St-germain, Denis Maro, L. Tenailleau, D. Hébert, M. Rozet, C. Noury, Christine Hatté, Martine PaterneAbstract:COGEMA La Hague Nuclear Reprocessing plant is located in the North West of Cotentin peninsula near Cherbourg (France). This Nuclear plant releases radioelements in atmosphere and in the English Channel. About 8.5 TBq.year -1 of radiocarbon are released as the liquid wastes through a pipe a few kilometres off sea shore, West of the Reprocessing plant. Recent studies in the peninsula show anomalous higher radiocarbon contents in vegetation near the coast that have suggested a supplementary marine contribution through the degassing of the 14 C excess supplied by liquid releases of the Nuclear plant. Carbon dioxide partial pressure, 14 C activities were measured in air and sea water in the Bay of Seine and around the COGEMA-La Hague Nuclear Reprocessing plant during three cruises in 2000 and 2002. Results show clearly that sea is a source of CO2 and 14 C to the atmosphere. Higher 14 C concentrations in air and water related to the La Hague liquid wastes are clearly recorded. The aim of this paper is to show results of these oceanographic campaigns. Flux between seawater and atmosphere are calculated in the North- West Cotentin and in Bay of Seine.
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14C Sources and Distribution in the Vicinity of La Hague Nuclear Reprocessing Plant: Part Ii—Marine Environment
Radiocarbon, 2004Co-Authors: Denis Maro, D. Hébert, Christine Hatté, Michel Fontugne, M. RozetAbstract:Carbon dioxide partial pressure and radiocarbon activity were measured in air and seawater in the Bay of Seine and around the COGEMA-La Hague Nuclear Reprocessing plant (northwest France) during 3 cruises in 2000 and 2002. Results clearly show that the sea is a source of CO2 and 14C to the atmosphere. High 14C concentrations in air and water related to the La Hague liquid waste are clearly recorded. For the restricted area of the Bay of Seine, CO2 carbon and 14C fluxes were estimated, indicating that less than 3% of the liquid 14C release is introduced in the atmosphere.
Ramunas Stepanauskas - One of the best experts on this subject based on the ideXlab platform.
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129I in Swedish rivers: distribution and sources.
The Science of the total environment, 2003Co-Authors: A Kekli, N Buraglio, Markus Meili, A Aldahan, G Possnert, Ramunas StepanauskasAbstract:We analyzed the concentration of 129I in the water of 26 rivers covering most of the runoff from Sweden, with the aim of assessing current contamination levels, distribution patterns and potential sources in freshwater systems of northern Europe. The results show relatively high values (up to 1.4 x 10(9) atoms l(-1)), steeply decreasing levels with increasing latitude and a positive correlation with Cl concentration and other chemical parameters. The 129I concentrations observed in south Sweden are probably the highest ever recorded in rivers without any direct discharge from a Nuclear installation. The strong latitudinal dependence suggests a northward dilution and possibly depletion of the isotope and a transport from a source located to the south. The most plausible source of the 129I in the studied rivers is atmospheric fallout of 129I emitted either by atmospheric discharges from the Nuclear Reprocessing facilities at Sellafield (England) and La Hague (France) or by volatilization from seawater contaminated by the same sources. The question is now whether and at what rate the 129I concentration in Nordic watersheds will increase further if discharges from Nuclear Reprocessing continue.
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129I in Swedish rivers: distribution and sources.
Science of The Total Environment, 2003Co-Authors: A Kekli, N Buraglio, Ala Aldahan, Göran Possnert, Markus Meili, Ramunas StepanauskasAbstract:We analyzed the concentration of I-129 in the water of 26 rivers covering most of the runoff from Sweden, with the aim of assessing current contamination levels, distribution patterns and potential sources in freshwater systems of northern Europe. The results show relatively high values (up to 1.4 x 10(9) atoms 1(-1)), steeply decreasing levels with increasing latitude and a positive correlation with Cl concentration and other chemical parameters. The I-129 concentrations observed in south Sweden are probably the highest ever recorded in rivers without any direct discharge from a Nuclear installation. The strong latitudinal dependence suggests a northward dilution and possibly depletion of the isotope and a transport from a source located to the south. The most plausible source of the I-129 in the studied rivers is atmospheric fallout of I-129 emitted either by atmospheric discharges from the Nuclear Reprocessing facilities at Sellafield (England) and La Hague (France) or by volatilization from seawater contaminated by the same sources. The question is now whether and at what rate the I-129 concentration in Nordic watersheds will increase further if discharges from Nuclear Reprocessing continue. (C) 2003 Elsevier Science B.V. All rights reserved.
Denis Maro - One of the best experts on this subject based on the ideXlab platform.
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14C sources and distribution in the vicinity of La Hague Nuclear Reprocessing plant. Part I: Terrestrial environment
Radiocarbon, 2016Co-Authors: Michel Fontugne, Denis Maro, D. Hébert, Christine Hatté, Y. Baron, Eric DouvilleAbstract:COGEMA-La Hague Nuclear Reprocessing plant in the Cotentin Peninsula (northwest France) releases in the atmosphere about 19 TBq.yr (super -1) of radiocarbon. Three experiments in a terrestrial environment with sampling of a bio-indicator like furze were performed in 1997, 1998, and 1999, and additional air samples in the chimney plume were measured. Results presented here establish the (super 14) C distribution in the La Hague environment and suggest that a part of the (super 14) C content in the vegetation near the coast results from a (super 14) CO (sub 2) degassing of seawater supplied with the liquid waste from the Nuclear plant.
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comparison of rimpuff hysplit adms atmospheric dispersion model outputs using emergency response procedures with 85kr measurements made in the vicinity of Nuclear Reprocessing plant
Journal of Environmental Radioactivity, 2013Co-Authors: O Connan, Denis Maro, Kilian Smith, Catherine Organo, L Solier, D. HébertAbstract:Abstract The Institut de Radioprotection et de Surete Nucleaire (IRSN) performed a series of 85Kr air sampling campaigns at mesoscale distances (18–50 km) from the AREVA NC La Hague Nuclear Reprocessing plant (North West France) between 2007 and 2009. The samples were collected in order to test and optimise a technique to measure low krypton-85 (85Kr) air concentrations and to investigate the performance of three atmospheric dispersion models (RIMPUFF, HYSPLIT, and ADMS), This paper presents the 85Kr air concentrations measured at three sampling locations which varied from 2 to 8000 Bq m−3, along with the 85Kr air concentrations output by the dispersion models. The dispersion models made reasonable estimates of the mean concentrations of 85Kr field measurements during steady wind conditions. In contrast, the models failed to accurately predict peaks in 85Kr air concentration during periods of rapid and large changes in wind speed and/or wind direction. At distances where we made the comparisons (18–50 km), in all cases, the models underestimated the air concentration activities.
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Comparison of RIMPUFF, HYSPLIT, ADMS atmospheric dispersion model outputs, using emergency response procedures, with 85Kr measurements made in the vicinity of Nuclear Reprocessing plant
Journal of Environmental Radioactivity, 2013Co-Authors: O Connan, Denis Maro, Kilian Smith, Catherine Organo, L Solier, D. HébertAbstract:The Institut de Radioprotection et de Sureté Nucléaire (IRSN) performed a series of 85Kr air sampling campaigns at mesoscale distances (18-50km) from the AREVA NC La Hague Nuclear Reprocessing plant (North West France) between 2007 and 2009. The samples were collected in order to test and optimise a technique to measure low krypton-85 (85Kr) air concentrations and to investigate the performance of three atmospheric dispersion models (RIMPUFF, HYSPLIT, and ADMS),This paper presents the 85Kr air concentrations measured at three sampling locations which varied from 2 to 8000Bqm-3, along with the 85Kr air concentrations output by the dispersion models. The dispersion models made reasonable estimates of the mean concentrations of 85Kr field measurements during steady wind conditions. In contrast, the models failed to accurately predict peaks in 85Kr air concentration during periods of rapid and large changes in wind speed and/or wind direction. At distances where we made the comparisons (18-50km), in all cases, the models underestimated the air concentration activities. © 2013 Elsevier Ltd.
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Carbon 14 transfer from seawater to the atmosphere through degassing processes in the Bay of Seine (North-West of France)
Radioprotection, 2005Co-Authors: Michel Fontugne, Pascale St-germain, Denis Maro, L. Tenailleau, D. Hébert, M. Rozet, C. Noury, Christine Hatté, Martine PaterneAbstract:COGEMA La Hague Nuclear Reprocessing plant is located in the North West of Cotentin peninsula near Cherbourg (France). This Nuclear plant releases radioelements in atmosphere and in the English Channel. About 8.5 TBq.year -1 of radiocarbon are released as the liquid wastes through a pipe a few kilometres off sea shore, West of the Reprocessing plant. Recent studies in the peninsula show anomalous higher radiocarbon contents in vegetation near the coast that have suggested a supplementary marine contribution through the degassing of the 14 C excess supplied by liquid releases of the Nuclear plant. Carbon dioxide partial pressure, 14 C activities were measured in air and sea water in the Bay of Seine and around the COGEMA-La Hague Nuclear Reprocessing plant during three cruises in 2000 and 2002. Results show clearly that sea is a source of CO2 and 14 C to the atmosphere. Higher 14 C concentrations in air and water related to the La Hague liquid wastes are clearly recorded. The aim of this paper is to show results of these oceanographic campaigns. Flux between seawater and atmosphere are calculated in the North- West Cotentin and in Bay of Seine.
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14C Sources and Distribution in the Vicinity of La Hague Nuclear Reprocessing Plant: Part Ii—Marine Environment
Radiocarbon, 2004Co-Authors: Denis Maro, D. Hébert, Christine Hatté, Michel Fontugne, M. RozetAbstract:Carbon dioxide partial pressure and radiocarbon activity were measured in air and seawater in the Bay of Seine and around the COGEMA-La Hague Nuclear Reprocessing plant (northwest France) during 3 cruises in 2000 and 2002. Results clearly show that the sea is a source of CO2 and 14C to the atmosphere. High 14C concentrations in air and water related to the La Hague liquid waste are clearly recorded. For the restricted area of the Bay of Seine, CO2 carbon and 14C fluxes were estimated, indicating that less than 3% of the liquid 14C release is introduced in the atmosphere.
A Kekli - One of the best experts on this subject based on the ideXlab platform.
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129I in Swedish rivers: distribution and sources.
The Science of the total environment, 2003Co-Authors: A Kekli, N Buraglio, Markus Meili, A Aldahan, G Possnert, Ramunas StepanauskasAbstract:We analyzed the concentration of 129I in the water of 26 rivers covering most of the runoff from Sweden, with the aim of assessing current contamination levels, distribution patterns and potential sources in freshwater systems of northern Europe. The results show relatively high values (up to 1.4 x 10(9) atoms l(-1)), steeply decreasing levels with increasing latitude and a positive correlation with Cl concentration and other chemical parameters. The 129I concentrations observed in south Sweden are probably the highest ever recorded in rivers without any direct discharge from a Nuclear installation. The strong latitudinal dependence suggests a northward dilution and possibly depletion of the isotope and a transport from a source located to the south. The most plausible source of the 129I in the studied rivers is atmospheric fallout of 129I emitted either by atmospheric discharges from the Nuclear Reprocessing facilities at Sellafield (England) and La Hague (France) or by volatilization from seawater contaminated by the same sources. The question is now whether and at what rate the 129I concentration in Nordic watersheds will increase further if discharges from Nuclear Reprocessing continue.
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129I in Swedish rivers: distribution and sources.
Science of The Total Environment, 2003Co-Authors: A Kekli, N Buraglio, Ala Aldahan, Göran Possnert, Markus Meili, Ramunas StepanauskasAbstract:We analyzed the concentration of I-129 in the water of 26 rivers covering most of the runoff from Sweden, with the aim of assessing current contamination levels, distribution patterns and potential sources in freshwater systems of northern Europe. The results show relatively high values (up to 1.4 x 10(9) atoms 1(-1)), steeply decreasing levels with increasing latitude and a positive correlation with Cl concentration and other chemical parameters. The I-129 concentrations observed in south Sweden are probably the highest ever recorded in rivers without any direct discharge from a Nuclear installation. The strong latitudinal dependence suggests a northward dilution and possibly depletion of the isotope and a transport from a source located to the south. The most plausible source of the I-129 in the studied rivers is atmospheric fallout of I-129 emitted either by atmospheric discharges from the Nuclear Reprocessing facilities at Sellafield (England) and La Hague (France) or by volatilization from seawater contaminated by the same sources. The question is now whether and at what rate the I-129 concentration in Nordic watersheds will increase further if discharges from Nuclear Reprocessing continue. (C) 2003 Elsevier Science B.V. All rights reserved.
Markus Meili - One of the best experts on this subject based on the ideXlab platform.
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129I in Swedish rivers: distribution and sources.
The Science of the total environment, 2003Co-Authors: A Kekli, N Buraglio, Markus Meili, A Aldahan, G Possnert, Ramunas StepanauskasAbstract:We analyzed the concentration of 129I in the water of 26 rivers covering most of the runoff from Sweden, with the aim of assessing current contamination levels, distribution patterns and potential sources in freshwater systems of northern Europe. The results show relatively high values (up to 1.4 x 10(9) atoms l(-1)), steeply decreasing levels with increasing latitude and a positive correlation with Cl concentration and other chemical parameters. The 129I concentrations observed in south Sweden are probably the highest ever recorded in rivers without any direct discharge from a Nuclear installation. The strong latitudinal dependence suggests a northward dilution and possibly depletion of the isotope and a transport from a source located to the south. The most plausible source of the 129I in the studied rivers is atmospheric fallout of 129I emitted either by atmospheric discharges from the Nuclear Reprocessing facilities at Sellafield (England) and La Hague (France) or by volatilization from seawater contaminated by the same sources. The question is now whether and at what rate the 129I concentration in Nordic watersheds will increase further if discharges from Nuclear Reprocessing continue.
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129I in Swedish rivers: distribution and sources.
Science of The Total Environment, 2003Co-Authors: A Kekli, N Buraglio, Ala Aldahan, Göran Possnert, Markus Meili, Ramunas StepanauskasAbstract:We analyzed the concentration of I-129 in the water of 26 rivers covering most of the runoff from Sweden, with the aim of assessing current contamination levels, distribution patterns and potential sources in freshwater systems of northern Europe. The results show relatively high values (up to 1.4 x 10(9) atoms 1(-1)), steeply decreasing levels with increasing latitude and a positive correlation with Cl concentration and other chemical parameters. The I-129 concentrations observed in south Sweden are probably the highest ever recorded in rivers without any direct discharge from a Nuclear installation. The strong latitudinal dependence suggests a northward dilution and possibly depletion of the isotope and a transport from a source located to the south. The most plausible source of the I-129 in the studied rivers is atmospheric fallout of I-129 emitted either by atmospheric discharges from the Nuclear Reprocessing facilities at Sellafield (England) and La Hague (France) or by volatilization from seawater contaminated by the same sources. The question is now whether and at what rate the I-129 concentration in Nordic watersheds will increase further if discharges from Nuclear Reprocessing continue. (C) 2003 Elsevier Science B.V. All rights reserved.
