KEY ISSUES IN BIOSPHERE ASPECTS OF ASSESSMENT OF THE LONG TERM IMPACT OF CONTAMINANT RELEASES ASSOCIATED WITH RADIOACTIVE WASTE MANAGEMENT.
Welcome to the BIOPROTA website. We hope that this will allow those interested in biosphere-related aspects of radioactive waste disposal and the wider public to keep up to date with developments within the BIOPROTA programme.
Workshops reports and other publications of interest
BIOPROTA was set up to address the key uncertainties in long term assessments of contaminant releases into the environment arising from radioactive waste disposal.
The project focuses on key radionuclides and the key biosphere migration and accumulation mechanisms relevant to those radionuclides. The key radionuclides of interest are:
| Carbon-14 | Polonium-210 |
| Chlorine-36 | Radium-226 |
| Selenium-79 | Thorium-230 |
| Technetium-99 | Neptunium-237 |
| Iodine-129 | Uranium-238 |
| Lead-210 |
Participation is aimed at national authorities and agencies with responsibility for achieving safe and acceptable radioactive waste management, both regulators and operators. At the outset, it was recognised that there are radioecological and other data and information issues which are common to specific assessments required in many countries. The mutual support within a commonly focused project is intended to make more efficient use of skills and resources, and provide a transparent and traceable basis for the choices of parameter values as well as for the wider interpretation of information used in assessments.
BIOPROTA therefore seeks to provide a forum to address uncertainties in the assessment of the radiological impact of releases of long lived radionuclides in to the biosphere.
Overall the intention of BIOPROTA is to make available the best sources of information to justify modelling assumptions made within radiological assessments constructed to support radioactive waste management. Particular emphasis is placed on key data required for the assessment of long‑lived radionuclide migration and accumulation in the biosphere, and the associated radiological impact, following discharge to the environment or release from solid waste disposal facilities.
The project is driven by assessment needs identified from previous and on‑going assessment projects. Where common needs are identified within different assessment projects in different countries, a common effort can be applied to finding solutions. Such solutions may readily take account of the BIOMASS Theme 1 Data Protocol, among other things [IAEA, 2003“Reference Biospheres” for Solid Radioactive Waste Disposal: report of Theme 1 of the BIOsphere Modelling and ASSessment Programme (BIOMASS), IAEA-BIOMASS-6. International Atomic Energy Agency, Vienna.]
The modelling issues considered include:-
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the treatment of various features, events and processes (FEPs) of the systems under investigation;
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the development of conceptual models which correspond to an adequate approximation to those systems;
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mathematical representation of those conceptual models; and
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the choice of parameter values to adopt within those mathematical representations.
BIOPROTA achieves these objectives by
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holding an annual information exchange meeting;
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holding workshops on special topics; and
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by providing a mechanism for setting up collaborative projects.
BIOPROTA is a collaborative research Forum, managed and supported financially by a Sponsoring Committee. The Sponsoring Committee is coordinated by a Chairperson. In 2007, Svensk Kärnbränslehantering AB (SKB), Sweden, has agreed to supply the Chairperson. Details of all current member organisations are provided below.
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Organisation |
Representative |
Role of organisation |
Website |
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| 1 |
Agence Nationale pour la Gestion des Déchets Radioactifs (ANDRA) |
Elisabeth Leclerc-Cessac |
ANDRA is responsible for the management of radioactive waste in France. |
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| 2 | Belgian Nuclear Research Center, Foundation of Public Utility (SCK.CEN) | Yves Thiry |
With a view to sustaining development by R&D programmes,
training, communication and services, SCK•CEN contributes to:
- nuclear safety and radiation protection; - medical and industrial applications of radiation; the backend of the nuclear fuel cycle. |
http://www.sckcen.be/ |
| 3 | Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT) | Cristina Trueba | CIEMAT is a Public Research Spanish Agency for excellence in energy and the environment. Activities in the field of radiological protection extend to the public and to the environment. Ongoing research covers radioecology, evaluation of radiological impacts, environmental radioactivity measurements, and personal and environmental dosimetric impact assessments. |
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| 4 |
Electricité de France (EDF)
|
Philippe Ciffroy |
EDF is the main producer of electricity in France. The Laboratoire National Hydraulique et Environnement (LNHE) department works on migration of pollutants in the ground, waste management, water quality, soil contamination, ecotoxicology, ecology, microbiology, health risk assessment, and also fluvial and maritime hydraulics, resource management, industrial flows and combustion, meteorology and air quality. |
|
| 5 |
Korea Atomic Energy Research Institute (KAERI) |
Yong-Soo Hwang |
KAERI is developing the Korean reference concept for permanent disposal of high-level radioactive waste including spent nuclear fuel and assessing the long term post-closure safety and repository performance. |
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| 6 |
National Cooperative for the Disposal of Radioactive waste (Nagra)
|
Frits van Dorp |
Nagra has more than 30 years experience in the development of disposal concepts for all categories of radioactive waste. Over the years, Nagra has built up extensive technical know-how and has applied this in site characterisation and performance assessment of deep geological repositories. |
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| 7 |
Nexia Solutions Ltd (formerly BNFL Research & Technology) |
Mark Willans |
Nexia Solutions is a UK BNFL subsiduary company providing technology solutions and services across the nuclear fuel cycle. |
http://www.nexiasolutions.com/
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| 8 |
Nuclear Research Institute Rez (NRI)
|
Jiri Landa |
In the Czech Republic, NRI is the research, development and engineering organisation responsible for the development of nuclear power technologies, utilization of radionuclides and radiation in industry and medicine, and with a role to undertake fundamental research to support the long-term management and disposal of radioactive wastes. |
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| 9 |
Nuclear Waste Management Organization of Japan (NUMO) |
Keiichiro Wakasugi |
NUMO is the implementing body for the final disposal of vitrified high-level waste packaged from the spent fuel reprocessing plant. It is a government approved organization responsible for identification of a disposal site, and for the construction, operation and maintenance of the repository, closure of the facility, and post-closure institutional control. |
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| 10 |
Nuclear Waste Management Organization (NWMO) |
Paul Gierszewski |
NWMO is responsible for implementing a national approach across Canada for the long-term management of used fuel. |
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| 11 |
Posiva Oy |
Ari Ikonen |
Posiva is responsible for the management of disposal of spent fuel produced in power reactors in Finland, including siting, licencing, construction and operation of the repository. |
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| 12 |
Statens Strålskyddsinstitut (SSI) |
Bjorn Dverstorp |
SSI, is a government authority with the task of protecting people and the environment from the harmful effects of radiation. It ensures that the risks and benefits inherent to radiation and its use are compared and evaluated and is responsible for deciding on the dose limits for the general public and for workers exposed to radiation. |
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| 13 |
Svensk Kärnbränslehantering AB (SKB) |
Ulrik Kautsky |
SKB is responsible for management of Swedish radioactive waste, planning of waste repositories, waste logistics and site selection, including safety analysis, research and development of methods. |
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| 14 |
Japan Gas Corporation (JGC) |
Kunihiro Nakai |
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| 15 |
Nuclear Decommissioning Authority, Radioactive Waste Management Directoate (NDA, RWMD) |
Simon Norris |
Nuclear Decommissioning Authority Radioactive Waste Management Directorate (NDA RWMD) is responsible for supporting Government policy by developing and advising on safe, environmentally sound and publicly acceptable options for the long-term management of radioactive materials in the UK. |
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| 16 | Electric Power Research Institute (EPRI) | John Kessler | EPRI is an independent, nonprofit center for public interest energy and environmental research in the USA that brings together members, participants, the Institute's scientists and engineers, and other leading experts to work collaboratively on solutions to the challenges of electric power. These solutions span nearly every area of electricity generation, delivery, and use, including health, safety, and environment. |
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| 17 | Norwegian Radiation Protection Agency (NRPA) | Per Strand |
The Norwegian Radiation Protection Authority (NRPA) is the competent national authority in the area of radiation protection and nuclear safety in Norway and is responsible for overseeing the use of radioactive substances; coordinating contingency plans against nuclear accidents and radioactive fallout; monitoring natural and artificial radiation in the environment; and increasing knowledge of the occurrence, risk and effects of radiation. |
www.nrpa.no
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Consulting Ltd was appointed to provide administrative and technical support to the sponsoring committee, project leaders and participants
Participation by additional technical organisations in the various BIOPROTA working groups is invited. For further information contact Karen.smith@enviros.com.
BIOPROTA Publications
The initial BIOPROTA work programme was organised in three themes. Details of these, and the publications within those themes, are detailed below.
The BIOPROTA output is made available for use of others, but the participants and supporting organisations take no responsibility for the use of the material.
Theme 1: Development of a Data-Base for Key Radionuclides and Process Data
The overall objective of the BIOPROTA Database is to provide data and supporting information relating to key Features, Events and Processes (FEPs) and the behaviour of key radionuclides in the biosphere. Enviros have collated parameter information for inclusion in a database to support BIOPROTA forum members in biosphere modelling exercises.
Theme 2: Modelling Testing and Development Tasks
Theme 2 investigated the mathematical and conceptual modelling assumptions of key biosphere processes. There were six tasks under Theme 2:
Theme 2: Task 1 – Irrigation
The objective of this task was to investigate the calculation of doses arising from interception by growing crops using contaminated irrigation water and the consequent contamination of the food consumed by humans. The Theme 2 Task 1 report can be downloaded here.
Theme 2: Task 2 - Inhalation
The objective of this task was to investigate further the calculation of doses arising from inhalation of particles suspended from soils within which long-lived radionuclides, particularly alpha emitters, had accumulated. The Theme 2 Task 2 report can be downloaded here.
Theme 2: Task 3 - Model Review and Comparison for C-14 Dose Assessment
The objective of this task was to be able to model the transport and fate of C-14 and account for the treatment of C-14 processes, pathways and accumulation in the biosphere, including equilibration times between the newly arriving C-14 and stable C (C-13 and C-12) of the biosphere and its component system/ compartments. The Theme 2 Task 3 report can be downloaded here.
Theme 2: Task 4 - Model Comparison for Radionuclide Accumulation in Soils
The objective of this task was to discuss the objectives, definitions and results of an assessment model intercomparison. Focus was given to the long-term accumulation of long lived radionuclides in soils. Two often used scenarios were adapted as means of contamination, the well scenario, where contaminated well water is used for irrigation of agricultural land and a river scenario, where contaminated river water floods the agricultural land. The Theme 2 Task 4 report can be downloaded here.
Theme 2: Task 5 - Analogues
Analogue information can increase our conceptual understanding of long term repository behaviour and behaviour of radionuclides in the environment in support of post closure performance assessment. They can also provide quantitative data for Performance Assessment (PA) models and are a communication method to pass on information to a non-specialist audience.
The objective of this Task was to review past and present use and understanding of natural analogues relating to biotically-influenced biosphere processes with the intention of promoting considered application of them in future safety assessments and public communication. The output of Theme 2 Task 5 can be downloaded here.
Theme 2: Task 7 – Geosphere-Biosphere Interface Zone (GBIZ)
The objective of Task 7 within Theme 2 was to support better account of the treatment of radionuclide transfer through the geosphere-biosphere interface zone, and the related accumulation/dispersion/dilution processes which should be considered in order to provide appropriate confidence in PA results. The output of Theme 2 Task 7 can be downloaded here.
Theme 3: Site Characterisation, Experiments and Monitoring.
The objective of Theme 3 is to provide advice about the biosphere features of a site which it may be useful to determine because they are especially relevant to the evaluation of radiation exposures over the long term. In addition, advice is also to be prepared concerning the setting up of experiments and field measurements so that the output can be relevantly interpreted for use in radiological assessments. The output of Theme 3 can be downloaded here.
Workshops reports and other publications of interest
International Forum on Application of Guidance and Methodologies for Assessing Radiation Impacts on Non-Human Biota (NHB) from Radioactive Waste Disposal Facilities (PROBIOTA)
A forum on the application
of guidance and methodologies for assessing radiation impacts on
non-human biota from radioactive waste disposal facilities was held
from 31 January to 1 February 2007 at Lappeenranta, Finland, hosted
by Posiva. The workshop was attended by 15 participants from six
countries. Presentations were made by participants on developments
in international methods for assessing impacts of ionising radiation
on NHB and national experience in the application of methods to
waste disposal facilities. The workshop report is now available
here
International Forum on Chlorine-36 in the Biosphere
A forum on the behaviour of Cl-36 in the biosphere was held from 27 - 28
September 2006 at Chatenay-Malabry near Paris and was hosted by ANDRA.
The workshop was well attended by 33 participants from nine countries,
including operators and regulators. Various participants presented
their current models for assessing the radiological impact of Cl-36
ranging from those models using equilibrium concentration ratios those
using dynamic specific activity approaches. The chlorine cycle and the
behaviour of organic and inorganic chlorine was also discussed. The
workshop report is available
here.
The presentations are available here,
(Ciffory,
Higley,
Laciok,
Leclerc,
Nakai,
Oberg,
Oughton,
Shaw,
Tamponnet,
Thiry,
Thorne,
Introductions and Conclusions)
Evaluation of codes for geosphere and biosphere compartmental
contaminant transfer modelling
One of the goals of BIOPROTA is the search for opportunities of
synergies. A task currently under development within the forum is
therefore an inter-comparison of codes and their flexibilities for model
development and implementation.
The current wealth of models and codes is a sign of healthy independent
development by various agencies. Most agencies are moving away form hard
coded models, since they allow for little model flexibility, requiring
the user to modify the source code in order to adapt the model.
Comparing codes, illustrating their capacities, giving examples of their
strengths and weaknesses could enhance code refinement and help point
towards future development. A workshop on code comparisons was held at
ANDRA in September 2005, which provided a platform for knowledge
exchange on various codes and set the stage for synergy exploitation in
the fields of code, model and data base development.
In situ Study of the Long Term Sorption of Iodine onto Organic Matter
Iodine is generally present in environments as an anion (either iodide or iodate) and is therefore soluble in groundwater and migrates relatively quickly through rock and overburden to low-lying landscape positions such as wetlands where it can be retained by the organic matter of soils (iodine can only be retained in its oxidised form. This reaction with phenols, for example, is well known for I2 or I3-; the question is what controls the oxidation. Organic matter and bacterial activity seem to play an important role). Peat bogs are often located at low-lying landscape positions and are very rich in organic matter and therefore iodine is likely to “accumulate” in peat bogs.
An 18 month experimental study has been initiated, which aims to increase understanding of the mechanisms that govern the mobility and transport of iodine in peat bogs, and to acquire values for assessment models such as soil Kd and plant CR (concentration ratio). The study will focus on:
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the biogeochemical cycle of iodine in the peat bog including:
-the transfer of iodine along the carbon cycle in the peat bog (plant uptake, speciation of iodine in the plant, consequences of the biodegradation of the plant material on the availability of iodine in the peat); and,
-the role of the redox potential on the migration and the speciation of iodine in the peat bog.
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the retention of iodine onto the peat; and
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the relation between the chemistry of organic matter and the retention of iodine.
Such an understanding of the mechanisms that govern the fate of iodine in peat bogs will form the basis for a better model of the transfers of this element in these types of ecosystems.
Chlorine-36 Accumulation in Soil and Crop Uptake
Following the Cl-36 Forum (see Workshop reports), a new exercise was developed to compare various modelling approaches. These include:-
- the traditional approach involving assumed equilibrium sorption in soil and concentration ratios for root uptake (e.g. the model used in the IAEA BIOMASS reference biospheres examples);
- specific activity models; and
- more detailed process oriented models that take account of the interaction between hydrology and crop dynamics.
The objectives are to investigate:
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whether variation in predicted peak concentrations are the result of model structure;
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how much variation is inherent within all models;
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whether more advanced models improve predictions; and,
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whether more data could be used to reduce uncertainties and, if so, whether this can be derived from site independent research or by site characterisation.
Two phases of calculations are planned, the first based on the application of models to a simple assessment situation applied to specific sites or country circumstances, and, following review of the assumptions and results, a second phase to determine whether more complex approaches can reduce uncertainties, and under which conditions. The work is due to be completed in 2007. For more information contact Karen.smith@enviros.com
Additional tasks
In addition to the on-going tasks outlined above, the following tasks are currently under development within BIOPROTA. These include:
Towards a Consolidated and Integrated Data Set on Chlorine (Cl-36) Cycling in Forests - A post-doctoral study has been proposed on the cycling of chlorine in a Belgian forest. It is intended that an integrated data set on water and chlorine cycling within the forest and across the geosphere-biosphere interface zone will be derived through laboratory analysis of tree, litter fall, soil and groundwater samples. The output is intended to provide data on which ecosystem models can be based.
Specific Models for Carbon-14 Dose Assessment - A proposal has been developed for a task aimed at comparing models for C-14 behaviour in the biosphere and is currently under consideration within the forum.
Sensitivity Analysis of a Non-Human Biota Assessment Method – This task would involve an investigation of which assessment parameters effect non-human biota dose rates to the greatest degree in the EC ERICA Assessment Tool. It is intended that the task would help identify where further modelling or experimental work is required in order to reduce assessment uncertainties.
Site Characterisation – The BIOPROTA Theme 3 report on site characterisation was completed in 2006. a further task has been proposed for a coordinated programme to look into the choice of parameter values such as Kd and CF and whether there are instances in which such values are common to a number of sites or whether they are site specific.
Uranium Series Modelling – Two tasks are under consideration; the first looking at modelling the way in which U-238 and daughters decay and migrate following a long-term release and the second investigating non-equilibrium in a soil-plant system. A task looking into Rn-222 dose calculation in relation to inhalation and the gas pathway is also under consideration.
Historic Discharge Analogues - This task would aim to investigate the value of historical monitoring and concurrent environmental data associated with effluent discharges to a lake, a river estuary, and a tidal area. The objective would be to assess whether such data can provide a broad level of understanding and holistic information on the migration and fate of radioactivity in aquatic environments that could aide understanding of processes pertinent to post-closure safety assessment modelling.
Environmental Behaviour of Se-79 – An international workshop (similar to that held for Cl-36) on the environmental behaviour of Se-79, a radionuclide of importance for intermediate and low-level waste, is planned for the week commencing 5th May 2008. It is intended that the workshop would help identify the most important processes relating to this radionuclide. Further information on the workshop will be made available shortly.
Non-radioactive risks – An investigation into non-radioactive risks (chemical toxicity) associated with radioactive waste management facilities. It is intended that this task be developed following a review of current issues in international biosphere programmes.
Suggestions for additional tasks for inclusion within BIOPROTA should be sent to Karen.smith@enviros.com.
PAST MEETINGS
BIOPROTA are attended by representatives of the Sponsoring Committee and task group leader organisations and other interested bodies.
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June 2002 |
June 2002 Workshop Report |
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October 2002 |
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May 2003 |
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September 2003 |
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May 2004 |
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September 2004 |
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May 2005 |
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May 2006 |
May 2006 Workshop Report |
| May 2007 | May 2007 Workshop Report |
FUTURE MEETINGS
The next ANNUAL BIOPROTA FORUM is provisionally to be hosted by Nagra, Switzerland, in the week commencing 5-9 May 2008. Further information will be made available shortly.
If you would like further information about any of the activities of the BIOPROTA forum or are interested in membership, please contact karen.smith@enviros.com.