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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

THE NATIONAL CENTER FOR RADIOECOLOGY: A NETWORK OF EXCELLENCE FOR ENVIRONMENTAL AND HUMAN RADIATION RISK REDUCTION

Radioecology in the United States can be traced back to the early 1950s when small research programs were established to address the fate and effects of radionuclides released in the environment from activities at nuclear facilities. These programs focused primarily on local environmental effects, but global radioactive fallout from nuclear weapons testing and the potential for larger scale local releases of radioisotopes resulted in major concerns about the threat, not only to humans, but to other species and to ecosystems that support all life. These concerns were shared by other countries and it was quickly recognized that a multi-disciplinary approach would be required to address and understand the implications of anthropogenic radioactivity in the environment. The management, clean-up and long-term monitoring of legacy wastes at Department of Energy (DOE), Department of Defense (DOD), and Nuclear Regulatory Commission (NRC)-regulated facilities continues to be of concern as long as nuclear operations continue. Research conducted through radioecology programs provides the credible scientific data needed for decision-making purposes. The current status of radioecology programs in the United States are: fragmented with little coordination to identify national strategies and direct programs; suffering from a steadily decreasing funding base; soon to be hampered by closure of key infrastructure; hampered by aging and retiring workforce (loss of technical expertise); and in need of training of young scientists to ensure continuation of the science (no formal graduate education program in radioecology remaining in the U.S.). With these concerns in mind, the Savannah River National Laboratory (SRNL) took the lead to establish the National Center for Radioecology (NCoRE) as a network of excellence of the remaining radioecology expertise in the United States. As part of the NCoRE mission, scientists at SRNL are working with six key partner universities to re-establish a graduate education training program for radioecology. Recently, NCoRE hosted a workshop to identify the immediate needs for science-driven discoveries, tool development and the generation of scientific data to support the legislative decision-making process for remediation strategies, long-term monitoring of radiologically-contaminated sites and protection of human health and the environment. Some of the immediate strategic research needs were identified in the fields of functional genomics for determining low-dose effects, improved low-level dosimetry, and mixed (radiological and chemical) contaminant studies. Longer term strategic research and tool development areas included development of radioecology case study sites, comprehensive decision-making tools, consequence response actions, and optimized scenario based ecosystem modeling. A summary of the NCoRE workshop findings related to waste management needs and priority areas will be presented in this paper.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2013

The National Center for Radioecology (NCoRE): A Network of Excellence for Environmental and Human Radiation Risk Reduction - 13365

Radioecology in the United States can be traced back to the early 1950's when small research programs were established to address the fate and effects of radionuclides released in the environment from activities at nuclear facilities. These programs focused primarily on local environmental effects, but global radioactive fallout from nuclear weapons testing and the potential for larger scale local releases of radioisotopes resulted in major concerns about the threat, not only to humans, but to other species and to ecosystems that support all life. These concerns were shared by other countries and it was quickly recognized that a multi-disciplinary approach would be required to address and understand the implications of anthropogenic radioactivity in the environment. The management, clean-up and long-term monitoring of legacy wastes at Department of Energy (DOE), Department of Defense (DOD), and Nuclear Regulatory Commission (NRC)-regulated facilities continues to be of concern as long as nuclear operations continue. Research conducted through radioecology programs provides the credible scientific data needed for decision-making purposes. The current status of radioecology programs in the United States are: fragmented with little coordination to identify national strategies and direct programs; suffering from a steadily decreasing funding base; soon to be hampered by closure of key infrastructure; hampered by aging and retiring workforce (loss of technical expertise); and in need of training of young scientists to ensure continuation of the science (no formal graduate education program in radioecology remaining in the U.S.). With these concerns in mind, the Savannah River National Laboratory (SRNL) took the lead to establish the National Center for Radioecology (NCoRE) as a network of excellence of the remaining radioecology expertise in the United States. As part of the NCoRE mission, scientists at SRNL are working with six key partner universities to re-establish a graduate education training program for radioecology. Recently, NCoRE hosted a workshop to identify the immediate needs for science-driven discoveries, tool development and the generation of scientific data to support the legislative decision-making process for remediation strategies, long-term monitoring of radiologically- contaminated sites and protection of human health and the environment. Some of the immediate strategic research needs were identified in the fields of functional genomics for determining low-dose effects, improved low-level dosimetry, and mixed (radiological and chemical) contaminant studies. Longer term strategic research and tool development areas included development of radioecology case study sites, comprehensive decision-making tools, consequence response actions, and optimized scenario based ecosystem modeling. A summary of the NCoRE workshop findings related to waste management needs and priority areas will be presented in this paper. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

OVERVIEW OF THE COOPERATION BETWEEN THE CHERNOBYL CENTER'S INTERNATIONAL RADIOECOLOGY LABORATORY IN SLAVUTYCH, UKRAINE AND U.S. RESEARCH CENTERS BETWEEN 2000-2010

The International Radioecology Laboratory (IRL) located in Slavutych, Ukraine was created in 1999 under the initiative of the United States Government and the Government of Ukraine in the framework of international cooperation on evaluation and minimization of consequences of the Chernobyl nuclear power plant (ChNPP) accident. Since the time the IRL was founded, it has participated in a large number of projects, including the following: (1) study of radionuclide accumulation, distribution, and migration in components of various ecological systems of the Chernobyl Exclusion Zone (ChEZ); (2) radiation dose assessments; (3) study of the effects of radiation influence on biological systems; (4) expert analysis of isotopic and quantitative composition of radioactive contaminants; (5) development of new methods and technologies intended for radioecological research; (6) evaluation of future developments and pathways for potential remediation of the ChEZ areas; (7) assistance in provision of physical protection systems for ionizing irradiation sources at Ukrainian enterprises; (8) reviews of open Russian language publications on issues associated with consequences of the ChNPP accident, radioactive waste management, radioecological monitoring, and ChNPP decommissioning; (9) conduct of training courses on problems of radioecology, radiation safety, radioecological characterization of test sites and environmental media, and on research methods; (10) conduct of on-site scientific conferences and workshops on the ChEZ and radioecology problems; participation in off-site scientific conferences and meetings; and (11) preparation of scientific and popular science publications, and interactions with mass media representatives. This article provides a brief overview of the major achievements resulting from this cooperation between the IRL and U.S. research centers.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Integration of ecosystem science into radioecology: A consensus perspective

In the Fall of 2016 a workshop was held which brought together over 50 scientists from the ecological and radiological fields to discuss feasibility and challenges of reintegrating ecosystem science into radioecology. There is a growing desire to incorporate attributes of ecosystem science into radiological risk assessment and radioecological research more generally, fueled by recent advances in quantification of emergent ecosystem attributes and the desire to accurately reflect impacts of radiological stressors upon ecosystem function. This work is a synthesis of the discussions and consensus of the workshop participant's responses to three primary questions, which were: 1) How can ecosystem science support radiological risk assessment? 2) What ecosystem level endpoints potentially could be used for radiological risk assessment? and 3) What inference strategies and associated methods would be most appropriate to assess the effects of radionuclides on ecosystem structure and function? The consensus of the participants was that ecosystem science can and should support radiological risk assessment through the incorporation of quantitative metrics that reflect ecosystem functions which are sensitive to radiological contaminants. The participants also agreed that many such endpoints exit or are thought to exit and while many are used in ecological risk assessment currently, additional data need to be collected that link the causal mechanisms of radiological exposure to these endpoints. Finally, the participants agreed that radiological risk assessments must be designed and informed by rigorous statistical frameworks capable of revealing the causal inference tying radiological exposure to the endpoints selected for measurement.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Radioecological State of the Agrosphere in the 30-km Zone of the Siberian Chemical Combine During the Pre-Startup Period of a Prototype Power Complex

The results of radioecological monitoring of agricultural activities within the 30-km impact zone of the Siberian Chemical Combine are examined. The surface activity of {sup 137}Cs in soil and the specific activity of {sup 137}Cs in plants with similar indicators characteristic for NPP sites are analyzed and compared. The obtained data make it possible to evaluate the impact of a prototype electric power complex (PEPC) on the soil-and-vegetation cover and the products of agricultural activity, since the data make it possible to differentiate information on two basic parts – that associated with the activity of the Combine, on the one hand, and the other with the possible contribution of PEPC, on the other.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2021

Marshall Islands Dose Assessment and Radioecology Program: Report on the (i) 2018 Visual Study of Exterior Concrete of the Cactus Crater Containment Structure (ii) Periodic Monitoring of Groundwater on Runit Island and (iii) Initial Health Risk Assessment from Contaminants in the Cactus Crater Containment Structure

In 2012, Congress passed P.L. 112-149, Insular Areas Act of 2011, which amended the Compact of Free Association Amendments Act of 2003 by assigning Cactus Crater containment monitoring and reporting requirements to the Secretary of Energy (Secretary). Effective January 1, 2012, the Secretary was required to “periodically (but not less frequently than every 4 years) conduct -- (I) a visual study of the concrete exterior of the Cactus Crater Containment Structure on Runit Island; and (II) a radiochemical analysis of the groundwater surrounding and in the Cactus Crater Containment Structure on Runit Island.” 48 U.S.C. 1921b(f)(1)(B)(i). The Secretary was also directed to submit to Congress a report describing the results of each visual survey and the radiochemical analysis and “a determination on whether the surveys and analyses indicate any significant change in the health risks to the people of Enewetak from the contaminants within the Cactus Crater Containment Structure.” 48 U.S.C. 1921b(f)(1)(B)(ii)(II).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

EDITORIAL HPJ SPECIAL ISSUE INTRODUCTION

Radioecology is the study of the fate and transport and potential effects of radionuclides and associated contaminants in the environment. In short, it is the science that describes the fundamental connection between environmental health and human health risks. As such, radioecology can and has provided the credible, consistent and defensible basis for the successful and cost-effective environmental cleanup and closure of nuclear production and waste sites. In addition, radioecology also provides the technical basis for making timely and reliable decisions on cleanup in the aftermath of nuclear incidents such as Chernobyl and Fukushima. The 1986 Chernobyl Nuclear Power Plant (ChNPP) accident resulted in catastrophic health, social, and economic consequences in many countries, predominantly, Ukraine, Belarus, and Russia. The extent of radioactive contamination, levels and forms of contamination, and diversity of the ecosystems affected by the accident did not have any precedent and provided unique opportunities for environmental scientists around the world. Following the natural course of their development, populations of species and their communities found themselves in conditions of chronic radiation exposure that exceeded the natural background by factors of hundreds and thousands. Anything similar would have been extremely difficult if not impossible to recreate in a scientific laboratory. Consequently, since the first few years after the accident, many teams of scientists have visited the Chernobyl Exclusion Zone (ChEZ). The knowledge gained by studying the consequences of this accident has tremendous importance. The concept of an international research and technical center to address the problems involving nuclear and radiological accidents became a reality with the establishment of the International Chernobyl Center (ICC). In May 1995, the US and Ukraine signed a Protocol of Intent on establishment of the ICC, and the government of Ukraine appealed to the international scientific community to support ICC and join its activities (Chernobyl Center 2006). In December 1995, a memorandum of understanding (MOU) on the ChNPP closure was signed by the government of Ukraine, all of the G7 governments, and the European Commission. The ICC foundation was considered critical to ensure the safe decommissioning of the ChNPP reactor units and improvement of the safety of the Chernobyl Containment Shelter. On the 10th anniversary of the Chernobyl accident (26 April 1996), Mr. Viktor Yushchenko, the President of Ukraine, issued a decree to establish the Chernobyl Center for Nuclear Safety, Radioactive Waste and Radioecology (Chernobyl Center). On the same day, a MOU involving the US participation in Chernobyl Center activities was signed by the US and Ukraine (Chernobyl Center 2006). In July 1998, the US and Ukraine signed an agreement to establish the International Radioecology Laboratory (IRL) as part of the Chernobyl Center. The creation of IRL was a logical continuation of previous programs to conduct scientific research in radioecology and provide Ukraine and the rest of the world with the necessary infrastructure and scientific basis to conduct research in radioecology, radiobiology, dosimetry, and environmental protection in the ChEZ (Chernobyl Center 2006). A recent collaborative effort with IRL has been implemented through a project titled 'Long-term impacts from radiation/contamination within the Chernobyl Exclusion Zone' (Farfan et al. 2008; Gerdes et al. 2009; Marra et al. 2010). This collaboration had the following objectives: (1) Assess the long-term impacts to the environment from radiation exposure within the ChEZ; (2) Provide information on remediation guidelines and ecological risk assessment within radioactively contaminated territories based on the results of long-term field monitoring, analytical measurements, and numerical modeling of soils and groundwater radioactive contamination; and (3) Recommend the development and testing of effective cleanup technologies to reduce environmental and health risks. Based on this work, a large amount of data are now available for publication, some of which are presented in this Special Issue of the Health Physics Journal.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

RADIATION ECOLOGY ISSUES ASSOCIATED WITH MURINE RODENTS AND SHREWS IN THE CHERNOBYL EXCLUSION ZONE

This article describes major studies performed by the Chernobyl Center's International Radioecology Laboratory (Slavutich, Ukraine) on radioecology of murine rodents and shrews inhabiting the Chernobyl Exclusion Zone. The article addresses the long-term (1986-2005) and seasonal dynamics of radioactive contamination of animals, and reviews interspecies differences in radionuclide accumulations and factors affecting the radionuclide accumulations. It is shown that bioavailability of radionuclides in the 'soil-to-plant' chain and a trophic specialization of animals play key roles in determining their actual contamination levels. The total absorbed dose rates in small mammals significantly reduced during the years following the Chernobyl Nuclear Power Plant accident. In 1986, the absorbed dose rate reached 1.3-6.0 Gy hr{sup -1} in the central areas of the Chernobyl Exclusion Zone (the 'Red Forest'). In 1988 and 1990, the total absorbed dose rates were 1.3 and 0.42 Gy hr{sup -1}, respectively. In 1995, 2000, and 2005, according to the present study, the total absorbed dose rates rarely exceeded 0.00023, 0.00018, and 0.00015 Gy hr{sup -1}, respectively. Contributions of individual radiation sources into the total absorbed dose are described.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2016

Addressing ecological effects of radiation on populations and ecosystems to improve protection of the environment against radiation: Agreed statements from a Consensus Symposium

This paper reports the output of a consensus symposium organized by the International Union of Radioecology in November 2015. The symposium gathered an academically diverse group of 30 scientists to consider the still debated ecological impact of radiation on populations and ecosystems. Stimulated by the Chernobyl and Fukushima disasters' accidental contamination of the environment, there is increasing interest in developing environmental radiation protection frameworks. Scientific research conducted in a variety of laboratory and field settings has improved our knowledge of the effects of ionizing radiation on the environment. However, the results from such studies sometimes appear contradictory and there is disagreement about the implications for risk assessment. The Symposium discussions therefore focused on issues that might lead to different interpretations of the results, such as laboratory versus field approaches, organism versus population and ecosystemic inference strategies, dose estimation approaches and their significance under chronic exposure conditions. The participating scientists, from across the spectrum of disciplines and research areas, extending also beyond the traditional radioecology community, successfully developed a constructive spirit directed at understanding discrepancies. From the discussions, the group has derived seven consensus statements related to environmental protection against radiation, which are supplemented with some recommendations. Each of these statements is contextualized and discussed in view of contributing to the orientation and integration of future research, the results of which should yield better consensus on the ecological impact of radiation and consolidate suitable approaches for efficient radiological protection of the environment.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Irradiation Dose of the Woody Tier of a Coniferous Forest Due to Accidental Emissions from NPP

An approach to the comparative assessment of the impact of accidental radioactive emissions on the biota and radioecological validation of nuclear fuel cycle objects is presented. It is shown that the dose loads on woody tier in a coniferous forest as a result of severe accidents in NPPs with PWR-890, BWR-1412, and EPR-1600 significantly exceed the limit recommended by the ICRP. The impact of the radiation factor can result in serious disturbances in forest ecosystems in the immediate vicinity of NPPs.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2023

Multi-element isotopic analysis of hot particles from Chornobyl

Microscopic fuel fragments, so-called “hot particles”, were released during the 1986 accident at the Chornobyl nuclear powerplant and continue to contaminate the exclusion zone in northern Ukraine. Isotopic analysis can provide vital information about sample origin, history and contamination of the environment, though it has been underutilized due to the destructive nature of most mass spectrometric techniques, and inability to remove isobaric interference. Recent developments have diversified the range of elements that can be investigated through resonance ionization mass spectrometry (RIMS), notably in the fission products. The purpose of this study is to demonstrate the application of multi-element analysis on hot particles as relates to their burnup, particle formation in the accident, and weathering. The particles were analysed with two RIMS instruments: resonant-laser secondary neutral mass spectrometry (rL-SNMS) at the Institute for Radiation Protection and Radioecology (IRS) in Hannover, Germany, and laser ionization of neutrals (LION) at Lawrence Livermore National Laboratory (LLNL) in Livermore, USA. Comparable results across instruments show a range of burnup dependent isotope ratios for U and Pu and Cs, characteristic of RBMK-type reactors. Results for Rb, Ba and Sr show the influence of the environment, retention of Cs in the particles and time passed since fuel discharge.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2014

Radioecologycal study of {sup 239/240}Pu in Bangka Island and Muria Peninsula: Determination of {sup 239/240}Pu in marine sediment and seawater as part of baseline data collecting for sitting of candidates of first Indonesia NPP

Radioisotope Pu-239/240 are alpha emitting nuclides important indicators of radioactive contamination of the marine environment. Global fallout is the main source of plutonium in the marine environment. There are very limited study on {sup 239/240}Pu in Indonesia coastal environments. The data of this radioisotopes is needed for baseline data of nuclear power plant (NPP) site candidates both in Bangka Island and Muria Peninsula. Bottom sediments play an important role in radioecological studies of the marine environment because a large proportion of radioactive substances entering the sea is adsorbed over time onto suspended particulate matter and deposited in sediments. Plutonium is particle reactive and deposited in marine sediment. Radioisotope {sup 239/240}Pu was determinated by alpha spectrometry after radiochemical procedure that was performed in both water and marine sediment from Bangka Island and Muria Peninsula. The sediment baseline of concentration {sup 239/240}Pu in Bangka Island and Muria Peninsula were range from 0.013 to 0.021 Bq.kg{sup −1} and 0.018 to 0.024 Bq.kg{sup −1} respectively. The water baseline concentration this isotope were range from 2.73 to 4.05 mBq.m{sup −3} and 2.98 to 4.50 mBq.m{sup −3}.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Modeling and validating tritium transfer in a grassland ecosystem in response to {sup 3}H releases

In this paper a radioecological model (TOCATTA) for tritium transfer in a grassland ecosystem developed on an hourly time-step basis is proposed and compared with the first data set obtained in the vicinity of the AREVA-NC reprocessing plant of La Hague (France). The TOCATTA model aims at simulating dynamics of tritium transfer in agricultural soil and plant ecosystems exposed to time-varying HTO concentrations in air water vapour and possibly in irrigation and rain water. In the present study, gaseous releases of tritium from the AREVA NC nuclear reprocessing plant in normal operation can be intense and intermittent over a period of less than 24 hours. A first comparison of the model predictions with the field data has shown that TOCATTA should be improved in terms of kinetics of tritium transfer.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2011

RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND

Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2025

Fission gas trapped in Chornobyl fuel microparticles reveals details of reactor operations

The isotopic ratios of fission gas would provide important source information of a nuclear fuel sample found in the environment. However, it is believed that during a reactor accident like Chornobyl all fission gas is lost and that the radioactive particles found in the Chornobyl Exclusion Zone today are depleted in gases by the initial explosion and subsequent fire. We disprove this hypothesis by detection and analysis of trapped krypton and xenon in these particles. Our analysis of krypton and xenon isotopes by noble gas mass spectroscopy in combination with resonance ionization mass spectrometry establishes that important information about reactor operations like age, neutron flux and plutonium fission fraction can still be reconstructed from individual micrometer-sized particles even after decades of weathering in the environment.

Chornobyl↗
DOE OSTI2018

Excess Lead-210 and Plutonium-239+240: Two suitable radiogenic soil erosion tracers for mountain grassland sites

Highlights: • First application of excess Lead-210 as soil tracer in alpine grasslands. • {sup 239+240}Pu/{sup 137}Cs ratios indicated 75% Chernobyl contribution to {sup 137}Cs inventory. • {sup 239+240}Pu is compared to more mature radioisotopic tracers (i.e. {sup 210}Pb{sub ex} and {sup 137}Cs). • {sup 210}Pb{sub ex}, {sup 137}Cs and {sup 239+240}Pu yielded comparable estimates of soil redistribution. The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 ({sup 137}Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 ({sup 210}Pb{sub ex}) and Plutonium-239+240 ({sup 239+240}Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of −6.7 ± 1.1, −9.8 ± 6.8 and −7.0 ± 5.2 Mg ha{sup -1} yr{sup -1} for {sup 137}Cs, {sup 210}Pb{sub ex} and {sup 239+240}Pu, respectively. A mean soil loss of −5.7 ± 1.5, −5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (−5.2 ± 2.5, −4.5 ± 2.5 and −3.3 ± 2.4 Mg ha{sup -1} yr{sup -1} for {sup 137}Cs, {sup 210}Pb{sub ex} and {sup 239+240}Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, {sup 239+240}Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, {sup 210}Pb{sub ex} produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. {sup 210}Pb{sub ex} can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2013

The fate and behaviour of enhanced natural radioactivity with respect to environmental protection

In contrast to the monitoring and prevention of occupational radiation risk caused by enhanced natural radioactivity, relatively little attention has been paid to the environmental impact associated with residues containing enhanced activity concentration of naturally occurring radionuclides. Such materials are often deposited directly into the environment, a practice which is strictly forbidden in the management of other types of radioactive waste. In view of the new trends in radiation protection, the need to consider the occurrence of anthropogenically enhanced natural radioactivity as a particular unique case of environmental hazard is quite apparent. Residues containing high activity concentrations of some natural radionuclides differ from radioactive materials arising from the nuclear industry. In addition, the radiation risk is usually combined with the risk caused by other pollutants. As such and to date, there are no precise regulations regarding this matter and moreover, the non-nuclear industry is often not aware of potential environmental problems caused by natural radioactivity. This article discusses aspects of environmental radiation risks caused by anthropogenically enhanced natural radioactivity stored at unauthorised sites. Difficulties and inconclusiveness in the application of recommendations and models for radiation risk assessment are explored. General terms such as 'environmental effects' and the basic parameters necessary to carry out consistent and comparable Environmental Risk Assessment (ERA) have been developed and defined. - Highlights: Black-Right-Pointing-Pointer Features of environmental impact caused by residues containing high activity concentration of natural radionuclides Black-Right-Pointing-Pointer Definition of an effect of radiation on an ecosystem and novel method for its assessment Black-Right-Pointing-Pointer Radiation protection regulation inconclusiveness in the aspects of enhanced natural radioactivity.

54 ENVIRONMENTAL SCIENCES↗