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Research paper thumbnail of Considerations About Tenorm: A Study Case on Niobium Facilities

Health Physics, 2003

Two niobium mining facilities located at two different geological settings were selected as case ... more Two niobium mining facilities located at two different geological settings were selected as case studies for assessing the radiological impacts associated with mining and milling activities. The impacts were assessed both for operational and post-operational (future unrestricted use of the area) scenarios. The work methodology encompassed sampling and analysis of different materials along the operational process, including wastes, effluents and by-products, mass balance calculations, and dose assessment. The exposure scenario considered during the operational phase included the land use by hypothetical groups of members of the general public. In the case of post-operational phase the possible occupation of contaminated areas was considered. The results pointed out that during the operational phase of the investigated industries no relevant impacts could be attributed to them. However, in the case of the potential occupation of the contaminated areas where the wastes are being deposited, the unrestricted use of these areas cannot be accepted in terms of the relevant radiation protection requirements.

Research paper thumbnail of Radon Dynamics and Reduction in an Underground Mine in Brazil. Implications for Workers' Exposure

Radiation Protection Dosimetry, 2002

This work was aimed at studying the behaviour of 222Rn in an experimental underground copper mine... more This work was aimed at studying the behaviour of 222Rn in an experimental underground copper mine in Brazil with a single entrance. The 222Rn concentrations, meaured by using a dynamic radon measuring technique. varied between 30.5 Bq.m(-3), during ventilated conditions applied to the mine galleries, and 19.4 x 10(3) Bq.(-3) for non-ventilated conditions and when operational mining activities were conducted inside. High radon concentration surges were observed after blasting and drilling activities. In the cases of inadequate ventilation, it was estimated that workers could be subjected to exposures as high as 10 microSv.h(-1), only due to 222Rn and its short-lived progeny. The results show the importance of real-time measurements to evaluate radon dynamics during mining operations.

Research paper thumbnail of Challenges and opportunities of the Institute of Radioprotection and Dosimetry in looking for environmental safety solutions for the Brazilian private and public sectors

Research paper thumbnail of Water quality criteria: Application of a procedural approach of numeric criteria and risk assessment protocols to regulated toxicant concentrations in the aquatic environment

Research paper thumbnail of Proposal for an Innovative Approach to Prevent Acid Drainage from Uranium Mill Tailings Based on the Application of Na-Ferrate (Iron VI) 1

Journal of the American Society of Mining and Reclamation, 2006

The operation of uranium mining and milling plants gives rise to huge amounts of wastes from both... more The operation of uranium mining and milling plants gives rise to huge amounts of wastes from both mining and milling operations. Terrestrial deposition is the predominant method of disposal for waste-rock and tailings. When pyrite is present in these materials, the generation of acid drainage can take place and result in the contamination of underground and surface waters through the leaching of heavy metals and radionuclides. Ferrate (VI) is a powerful oxidizing agent in aqueous media. Under acidic conditions, the redox potential of the Ferrate (VI) ion is the highest of any other oxidant used in wastewater treatment processes. The standard half-cell reduction potential of ferrate (VI) has been determined as +2.20 V to + 0.72 V in acidic and basic solutions, respectively. Despite numerous beneficial properties in environmental applications, ferrate (VI) has remained commercially unavailable. Producing the dry, stabilized ferrate (VI) product required numerous process steps which le...

Research paper thumbnail of TENORM regulatory framework in Brazi

Research paper thumbnail of Evaluation of Metal Dynamics in Sediments of a Tropical Coastal Lagoon by Means of Radiotracers and Sequential Extractions

Radionuclides in the Study of Marine Processes, 1991

Jacarepagua tropical coastal lagoon, located in the south of Rio de Janeiro City, Brazil, undergo... more Jacarepagua tropical coastal lagoon, located in the south of Rio de Janeiro City, Brazil, undergoes a severe process of eutrofization and heavy metal pollution. Dredging of bottom sediment is an usual practice in the system which may account for metal remobilization, and consequently, increase of their concentration in the overlying water.

Research paper thumbnail of Integrated approach to planning the remediation of sites undergoing decommissioning

Available in abstract form only. Full text of publication follows: Decommissioning and remediatio... more Available in abstract form only. Full text of publication follows: Decommissioning and remediation activities are subject to some common driving forces that influence the ability of decommissioning and remediation programs to achieve end-states that correspond to planned or anticipated (future) end-uses (i.e., facility or site re-use). In addition, decommissioning and remediation programs have common resources needs that, when identified and fully utilized in an integrated framework, can result in optimizing the use of available resources to achieve risk-based results faster and at lower costs. To achieve this, it is necessary that the goals of individual decommissioning and remediation activities are aligned and not conflict with each other while costs are minimized and net health, safety, security and environmental benefits are maximized. Managing the decommissioning and remediation activities in an integrated program can result in enhanced environmental conditions, and/or reduced...

Research paper thumbnail of Radioecological characterization of a uranium mining site located in a semi-arid region in Brazil

Journal of Environmental Radioactivity, 2006

The work presents the radioecological characterization of the new Brazilian uranium mining and mi... more The work presents the radioecological characterization of the new Brazilian uranium mining and milling site located in a semi-arid region of the country. The process characterization demonstrated that in heap leach plants most of the 226 Ra remains in the leached ore. Despite the potential higher availability of radium isotopes in the soils of the studied region the lack of precipitation in that area reduces the leaching/mobilization of the radionuclides. High 226 Ra and 228 Ra concentrations were found in manioc while 210 Pb was significant in pasture. It was suggested that a range from 10 ÿ3 to 10 ÿ1 may conveniently encompass most of the transfer factors (TF) values for soil/plant systems (i.e. involving different cultures, different soils and natural radionuclides). Impacts due to aerial transportation of aerosols and radon generated in the mining were proved to be minimal and restricted to an area not greater than 15 km 2 .

Research paper thumbnail of Critical analysis of the waste management performance of two uranium production units in Brazil—part II: Caetite production center

Journal of Environmental Management, 2008

This paper discusses the environmental waste management of the Heap-Leach Uranium Production Faci... more This paper discusses the environmental waste management of the Heap-Leach Uranium Production Facility of Caetite´located in a semi-arid region in Brazil. A comparison is made with the first uranium production site of the country located in Poc-os de Caldas. It is demonstrated that differences in the operational process along with different environmental conditions can lead to different impacts. In the present case groundwater is the potential most sensitive environmental medium despite the well-established consensus in the literature that radon and aerosol emissions may turnout to be the most relevant environmental aspects of an installation located at this type of region. Most of the 226 Ra content in the ore remains in the leached ore that is deposited with the waste rock. A lack in appropriate prediction of the hydrological balance has been causing unanticipated emissions of liquid effluents into the environment. Chemical treatment of this effluent may be needed. Contamination of groundwater in the short term by the waste ponds is not to be expected but it can be a relevant issue in the long term. As a consequence, careful closure schemes will need to be put in place. Finally, the overall costs with remediation in the Caetite´production center are lower than those observed at the Poc-os de Caldas mining site.

Research paper thumbnail of Modeling the water flow in unsaturated waste rock pile: an important step in the overall closure planning of the first uranium mining site in Brazil

Uranium, Mining and Hydrogeology, 2008

Research paper thumbnail of Progress With Nuclear Energy Agency Task Group on Nuclear Site Restoration

Volume 2: Facility Decontamination and Decommissioning; Environmental Remediation; Environmental Management/Public Involvement/Crosscutting Issues/Global Partnering, 2013

The decommissioning of the twin 1040MWe PWRs at Zion, near Chicago USA is a ground breaking progr... more The decommissioning of the twin 1040MWe PWRs at Zion, near Chicago USA is a ground breaking programme. The original owner, Exelon Nuclear Corporation, transferred the full responsibility for reactor dismantling and site license termination to a subsidiary of EnergySolutions. The target end state of the Zion site for return to Exelon will be a green field with the exception of the dry fuel storage pad. In return, ZionSolutions has access to the full value of the decommissioning trust fund. There are two potential attractions of this model: lower overall cost and significant schedule acceleration. The Zion programme which commenced in September 2010 is designed to return the cleared site with an Independent Spent Fuel Storage Installation (ISFSI) pad in 2020, 12 years earlier than planned by Exelon. The overall cost, at 500Mperfullsizepowerreactorissignificantlybelowthelongruntrendof500M per full size power reactor is significantly below the long run trend of 500Mperfullsizepowerreactorissignificantlybelowthelongruntrendof750M+ per PWR. Implementation of the accelerated programme has been underway for nearly...

Research paper thumbnail of Societal constraints related to environmental remediation and decommissioning programmes

Journal of environmental radioactivity, Jan 20, 2017

The decisions related to decommissioning or environmental remediation projects (D/ER) cannot be i... more The decisions related to decommissioning or environmental remediation projects (D/ER) cannot be isolated from the socio-political and cultural environment. Experiences of the IAEA Member States point out the importance of giving due attention to the societal aspects in project planning and implementation. The purpose of this paper is threefold: i) to systematically review societal constraints that some organisations in different IAEA Member States encounter when implementing D/ER programmes, ii) to identify different approaches to overcome these constraints and iii) to collect examples of existing practices related to the integration of societal aspects in D/ER programmes worldwide. The research was conducted in the context of the IAEA project Constraints to Decommissioning and Environmental Remediation (CIDER). The research results show that societal constraints arise mostly as a result of the different perceptions, attitudes, opinions and concerns of stakeholders towards the risks...

Research paper thumbnail of Health Risk Assessment for Uranium in Groundwater - An Integrated Case Study Based on Hydrogeological Characterization and Dose Calculation

Research paper thumbnail of Chapter 6 Remediation as Part of the Decommissioning of Nuclear Facilities

Research paper thumbnail of Estratégias De Integração Multi-Institucional Da Gestão De Aqüíferos No Semi-Árido: Da Intervenção a Sustentabilidade

Aguas Subterrâneas, Sep 20, 2004

Resumo-O problema da escassez de água no mundo já foi bem diagnosticado, configurando-se como um ... more Resumo-O problema da escassez de água no mundo já foi bem diagnosticado, configurando-se como um dos grandes desafios para o século XXI. A literatura cientifica e os documentos e relatórios oficiais nacionais, como os da ANA, e internacionais, como os da UNESCO, apontam com riqueza de detalhes as carências e orientações gerais. No Brasil possui um caráter multifacetado que envolve vários setores da sociedade há décadas, e reveste-se de características dramáticas em algumas regiões do país, como é o caso do semi-árido nordestino. Este trabalho discute as estratégias de integração de competências para atender a demandas existentes na região do semi-árido, onde atuam instituições de várias áreas, visando o estabelecimento de parcerias que contribuam para melhorar a convivência com a seca. O objetivo geral é desenvolver arranjos multiinstitucionais técnico-científicos como ferramenta para a gestão dos aqüíferos, visando promover o uso sustentável da água subterrânea no semi-árido e possibilitar a implantação e/ou adequação de tecnologias para sistemas de produção familiar em áreas piloto. Espera-se também que a validação deste modelo conceitual de integração multi-institucional resulte futuramente em uma alternativa aplicável a outras áreas, respeitados seus condicionantes geo-sócio-econômicas.

Research paper thumbnail of Statistical modelling of heavy metal partitioning among their geochemical carrjers in sediments of rffieira bay, Rio de Janeiro, Brazil. A critical analysis

Http Dx Doi Org 10 1080 09593339309385289, Dec 17, 2008

Research paper thumbnail of Gestão ambiental em uma mina de urânio: levantamento de aspectos ambientais e critérios de relevância para implantação de uma política ambiental

Research paper thumbnail of Preliminary Results of the Water Flow Modeling in an Acid Drainage Generating Waste Rock Pile Located at the Uranium Mining Site of Poços De Caldas - BRAZIL1

The first uranium production center in Brazil began operation in 1982. After 13 years of a non-co... more The first uranium production center in Brazil began operation in 1982. After 13 years of a non-continuous operation, the mining activities were suspended definitively. Uranium was extracted by open pit mining. Operations gave rise to approximately 12.4×106 m3 of waste rock, while the mill process generated a volume of approximately 2.39×106 m3 of tailings. Regardless the fact that some studies

Research paper thumbnail of Impactos radiológicos da indústria do fosfato

Research paper thumbnail of Considerations About Tenorm: A Study Case on Niobium Facilities

Health Physics, 2003

Two niobium mining facilities located at two different geological settings were selected as case ... more Two niobium mining facilities located at two different geological settings were selected as case studies for assessing the radiological impacts associated with mining and milling activities. The impacts were assessed both for operational and post-operational (future unrestricted use of the area) scenarios. The work methodology encompassed sampling and analysis of different materials along the operational process, including wastes, effluents and by-products, mass balance calculations, and dose assessment. The exposure scenario considered during the operational phase included the land use by hypothetical groups of members of the general public. In the case of post-operational phase the possible occupation of contaminated areas was considered. The results pointed out that during the operational phase of the investigated industries no relevant impacts could be attributed to them. However, in the case of the potential occupation of the contaminated areas where the wastes are being deposited, the unrestricted use of these areas cannot be accepted in terms of the relevant radiation protection requirements.

Research paper thumbnail of Radon Dynamics and Reduction in an Underground Mine in Brazil. Implications for Workers' Exposure

Radiation Protection Dosimetry, 2002

This work was aimed at studying the behaviour of 222Rn in an experimental underground copper mine... more This work was aimed at studying the behaviour of 222Rn in an experimental underground copper mine in Brazil with a single entrance. The 222Rn concentrations, meaured by using a dynamic radon measuring technique. varied between 30.5 Bq.m(-3), during ventilated conditions applied to the mine galleries, and 19.4 x 10(3) Bq.(-3) for non-ventilated conditions and when operational mining activities were conducted inside. High radon concentration surges were observed after blasting and drilling activities. In the cases of inadequate ventilation, it was estimated that workers could be subjected to exposures as high as 10 microSv.h(-1), only due to 222Rn and its short-lived progeny. The results show the importance of real-time measurements to evaluate radon dynamics during mining operations.

Research paper thumbnail of Challenges and opportunities of the Institute of Radioprotection and Dosimetry in looking for environmental safety solutions for the Brazilian private and public sectors

Research paper thumbnail of Water quality criteria: Application of a procedural approach of numeric criteria and risk assessment protocols to regulated toxicant concentrations in the aquatic environment

Research paper thumbnail of Proposal for an Innovative Approach to Prevent Acid Drainage from Uranium Mill Tailings Based on the Application of Na-Ferrate (Iron VI) 1

Journal of the American Society of Mining and Reclamation, 2006

The operation of uranium mining and milling plants gives rise to huge amounts of wastes from both... more The operation of uranium mining and milling plants gives rise to huge amounts of wastes from both mining and milling operations. Terrestrial deposition is the predominant method of disposal for waste-rock and tailings. When pyrite is present in these materials, the generation of acid drainage can take place and result in the contamination of underground and surface waters through the leaching of heavy metals and radionuclides. Ferrate (VI) is a powerful oxidizing agent in aqueous media. Under acidic conditions, the redox potential of the Ferrate (VI) ion is the highest of any other oxidant used in wastewater treatment processes. The standard half-cell reduction potential of ferrate (VI) has been determined as +2.20 V to + 0.72 V in acidic and basic solutions, respectively. Despite numerous beneficial properties in environmental applications, ferrate (VI) has remained commercially unavailable. Producing the dry, stabilized ferrate (VI) product required numerous process steps which le...

Research paper thumbnail of TENORM regulatory framework in Brazi

Research paper thumbnail of Evaluation of Metal Dynamics in Sediments of a Tropical Coastal Lagoon by Means of Radiotracers and Sequential Extractions

Radionuclides in the Study of Marine Processes, 1991

Jacarepagua tropical coastal lagoon, located in the south of Rio de Janeiro City, Brazil, undergo... more Jacarepagua tropical coastal lagoon, located in the south of Rio de Janeiro City, Brazil, undergoes a severe process of eutrofization and heavy metal pollution. Dredging of bottom sediment is an usual practice in the system which may account for metal remobilization, and consequently, increase of their concentration in the overlying water.

Research paper thumbnail of Integrated approach to planning the remediation of sites undergoing decommissioning

Available in abstract form only. Full text of publication follows: Decommissioning and remediatio... more Available in abstract form only. Full text of publication follows: Decommissioning and remediation activities are subject to some common driving forces that influence the ability of decommissioning and remediation programs to achieve end-states that correspond to planned or anticipated (future) end-uses (i.e., facility or site re-use). In addition, decommissioning and remediation programs have common resources needs that, when identified and fully utilized in an integrated framework, can result in optimizing the use of available resources to achieve risk-based results faster and at lower costs. To achieve this, it is necessary that the goals of individual decommissioning and remediation activities are aligned and not conflict with each other while costs are minimized and net health, safety, security and environmental benefits are maximized. Managing the decommissioning and remediation activities in an integrated program can result in enhanced environmental conditions, and/or reduced...

Research paper thumbnail of Radioecological characterization of a uranium mining site located in a semi-arid region in Brazil

Journal of Environmental Radioactivity, 2006

The work presents the radioecological characterization of the new Brazilian uranium mining and mi... more The work presents the radioecological characterization of the new Brazilian uranium mining and milling site located in a semi-arid region of the country. The process characterization demonstrated that in heap leach plants most of the 226 Ra remains in the leached ore. Despite the potential higher availability of radium isotopes in the soils of the studied region the lack of precipitation in that area reduces the leaching/mobilization of the radionuclides. High 226 Ra and 228 Ra concentrations were found in manioc while 210 Pb was significant in pasture. It was suggested that a range from 10 ÿ3 to 10 ÿ1 may conveniently encompass most of the transfer factors (TF) values for soil/plant systems (i.e. involving different cultures, different soils and natural radionuclides). Impacts due to aerial transportation of aerosols and radon generated in the mining were proved to be minimal and restricted to an area not greater than 15 km 2 .

Research paper thumbnail of Critical analysis of the waste management performance of two uranium production units in Brazil—part II: Caetite production center

Journal of Environmental Management, 2008

This paper discusses the environmental waste management of the Heap-Leach Uranium Production Faci... more This paper discusses the environmental waste management of the Heap-Leach Uranium Production Facility of Caetite´located in a semi-arid region in Brazil. A comparison is made with the first uranium production site of the country located in Poc-os de Caldas. It is demonstrated that differences in the operational process along with different environmental conditions can lead to different impacts. In the present case groundwater is the potential most sensitive environmental medium despite the well-established consensus in the literature that radon and aerosol emissions may turnout to be the most relevant environmental aspects of an installation located at this type of region. Most of the 226 Ra content in the ore remains in the leached ore that is deposited with the waste rock. A lack in appropriate prediction of the hydrological balance has been causing unanticipated emissions of liquid effluents into the environment. Chemical treatment of this effluent may be needed. Contamination of groundwater in the short term by the waste ponds is not to be expected but it can be a relevant issue in the long term. As a consequence, careful closure schemes will need to be put in place. Finally, the overall costs with remediation in the Caetite´production center are lower than those observed at the Poc-os de Caldas mining site.

Research paper thumbnail of Modeling the water flow in unsaturated waste rock pile: an important step in the overall closure planning of the first uranium mining site in Brazil

Uranium, Mining and Hydrogeology, 2008

Research paper thumbnail of Progress With Nuclear Energy Agency Task Group on Nuclear Site Restoration

Volume 2: Facility Decontamination and Decommissioning; Environmental Remediation; Environmental Management/Public Involvement/Crosscutting Issues/Global Partnering, 2013

The decommissioning of the twin 1040MWe PWRs at Zion, near Chicago USA is a ground breaking progr... more The decommissioning of the twin 1040MWe PWRs at Zion, near Chicago USA is a ground breaking programme. The original owner, Exelon Nuclear Corporation, transferred the full responsibility for reactor dismantling and site license termination to a subsidiary of EnergySolutions. The target end state of the Zion site for return to Exelon will be a green field with the exception of the dry fuel storage pad. In return, ZionSolutions has access to the full value of the decommissioning trust fund. There are two potential attractions of this model: lower overall cost and significant schedule acceleration. The Zion programme which commenced in September 2010 is designed to return the cleared site with an Independent Spent Fuel Storage Installation (ISFSI) pad in 2020, 12 years earlier than planned by Exelon. The overall cost, at 500Mperfullsizepowerreactorissignificantlybelowthelongruntrendof500M per full size power reactor is significantly below the long run trend of 500Mperfullsizepowerreactorissignificantlybelowthelongruntrendof750M+ per PWR. Implementation of the accelerated programme has been underway for nearly...

Research paper thumbnail of Societal constraints related to environmental remediation and decommissioning programmes

Journal of environmental radioactivity, Jan 20, 2017

The decisions related to decommissioning or environmental remediation projects (D/ER) cannot be i... more The decisions related to decommissioning or environmental remediation projects (D/ER) cannot be isolated from the socio-political and cultural environment. Experiences of the IAEA Member States point out the importance of giving due attention to the societal aspects in project planning and implementation. The purpose of this paper is threefold: i) to systematically review societal constraints that some organisations in different IAEA Member States encounter when implementing D/ER programmes, ii) to identify different approaches to overcome these constraints and iii) to collect examples of existing practices related to the integration of societal aspects in D/ER programmes worldwide. The research was conducted in the context of the IAEA project Constraints to Decommissioning and Environmental Remediation (CIDER). The research results show that societal constraints arise mostly as a result of the different perceptions, attitudes, opinions and concerns of stakeholders towards the risks...

Research paper thumbnail of Health Risk Assessment for Uranium in Groundwater - An Integrated Case Study Based on Hydrogeological Characterization and Dose Calculation

Research paper thumbnail of Chapter 6 Remediation as Part of the Decommissioning of Nuclear Facilities

Research paper thumbnail of Estratégias De Integração Multi-Institucional Da Gestão De Aqüíferos No Semi-Árido: Da Intervenção a Sustentabilidade

Aguas Subterrâneas, Sep 20, 2004

Resumo-O problema da escassez de água no mundo já foi bem diagnosticado, configurando-se como um ... more Resumo-O problema da escassez de água no mundo já foi bem diagnosticado, configurando-se como um dos grandes desafios para o século XXI. A literatura cientifica e os documentos e relatórios oficiais nacionais, como os da ANA, e internacionais, como os da UNESCO, apontam com riqueza de detalhes as carências e orientações gerais. No Brasil possui um caráter multifacetado que envolve vários setores da sociedade há décadas, e reveste-se de características dramáticas em algumas regiões do país, como é o caso do semi-árido nordestino. Este trabalho discute as estratégias de integração de competências para atender a demandas existentes na região do semi-árido, onde atuam instituições de várias áreas, visando o estabelecimento de parcerias que contribuam para melhorar a convivência com a seca. O objetivo geral é desenvolver arranjos multiinstitucionais técnico-científicos como ferramenta para a gestão dos aqüíferos, visando promover o uso sustentável da água subterrânea no semi-árido e possibilitar a implantação e/ou adequação de tecnologias para sistemas de produção familiar em áreas piloto. Espera-se também que a validação deste modelo conceitual de integração multi-institucional resulte futuramente em uma alternativa aplicável a outras áreas, respeitados seus condicionantes geo-sócio-econômicas.

Research paper thumbnail of Statistical modelling of heavy metal partitioning among their geochemical carrjers in sediments of rffieira bay, Rio de Janeiro, Brazil. A critical analysis

Http Dx Doi Org 10 1080 09593339309385289, Dec 17, 2008

Research paper thumbnail of Gestão ambiental em uma mina de urânio: levantamento de aspectos ambientais e critérios de relevância para implantação de uma política ambiental

Research paper thumbnail of Preliminary Results of the Water Flow Modeling in an Acid Drainage Generating Waste Rock Pile Located at the Uranium Mining Site of Poços De Caldas - BRAZIL1

The first uranium production center in Brazil began operation in 1982. After 13 years of a non-co... more The first uranium production center in Brazil began operation in 1982. After 13 years of a non-continuous operation, the mining activities were suspended definitively. Uranium was extracted by open pit mining. Operations gave rise to approximately 12.4×106 m3 of waste rock, while the mill process generated a volume of approximately 2.39×106 m3 of tailings. Regardless the fact that some studies

Research paper thumbnail of Impactos radiológicos da indústria do fosfato