Over the past decade, the BIOPROTA forum has undertaken a number of projects relating to the behaviour C-14 in the biosphere, both in terms of a review of the assessment models used, and the modelling of C-14 uptake in agricultural crops. To date, the model comparison studies undertaken in BIOPROTA for C-14 have used hypothetical release scenarios, with no data to support the results reported.
Independently of BIOPROTA studies, a number of waste management and research organisations have been further developing their in-house C-14 modelling capabilities, and testing their conceptual models against real world datasets. These have all focussed on modelling the uptake of C-14 into plants, and have utilised both laboratory and field data. The French Institute for Radioprotection and Nuclear Safety (IRSN) in particular, have used the application of their TOCATTA model to the La Hague field data [Les Dizès et al., 2012] to further develop their conceptual model, which is now referred to as TOCATTA-χ [Aulagnier et al., 2013].
The proposed work programme is therefore designed to provide participants with an opportunity to test and potentially validate their models of C-14 dynamics in terrestrial ecosystems using real world data.
The specific objective of this project is, based upon the interests of the participating organisations, to facilitate the validation of aspects of existing terrestrial biosphere models for C-14 using real world data. It may also provide participating organisations with the opportunity to undertake model development during this project, or in the future as a result of this study.
A BIOPROTA workshop on C-14 in the biosphere is due to be held 10 – 11 April 2019, hosted by IRSN in Aix-en-Provence, France. The workshop has the objectives of (i) presenting and discussing research and assessment modelling experience relating to C-14 in terrestrial and aquatic systems, (ii) reviewing the progress made in parallel with the BIOPROTA studies relating to C-14, and (iii) identifying opportunities for building further confidence and/or further potential improvements in the representation of C-14 in biosphere assessments.
The International Atomic Energy Agency (IAEA) BIOMASS-6 report on reference biospheres for solid radioactive waste disposal was published in 2003 following an extensive international collaborative work program. The report sets out a structured approach for the assessment of impacts of radionuclide releases to the biosphere from radioactive waste disposal facilities. It also includes examples of the application of the methodology, called Example Reference Biospheres (ERBs) and associated results expressed in terms of radiation dose rates to humans for unit release rates of some relevant radionuclides.
With the focus of such assessments being on long-term future biosphere conditions, the methodology was intended to support the development of biosphere models as a measuring instrument, providing assessment results for comparison with protection objectives rather than a prediction of future conditions and exposures.
Given the significant developments in a wide range of factors including technical developments in models for radionuclide migration and accumulation, climate change model treatments and site investigation, characterisation methods and their interpretation, it is considered timely for the reference biospheres methodology to be internationally reviewed and enhanced to take account of this new knowledge and experience.
The first project meeting took place in April 2016 in Brussels, Belgium (hosted by FANC) after the Annual BIOPROTA meeting.
The workshop report can be downloaded here.
The second workshop was held in conjunction with the first Technical Meeting of the IAEA MODARIA II programme, working group 6).
The report from this meeting can be downloaded here.
A third project workshop took place in Switzerland in May 2016, hosted by ENSI.
The meeting report can be downloaded here.
The fourth BIOMASS-6 workshop took place in conjunction with the MODARIA II workshop in Vienna in October-November 2017.
This meeting report can be downloaded here.
In March 2018, the BIOMASS 2020 interim report was issued by SKB.
This can be downloaded here from the SKB website.
The fifth workshop took place jointly with the second Interim Meeting of Working Group 6 (WG6) of the International Atomic Energy Agency (IAEA) second phase programme concerning MODARIA II in Kerava, Finland from 16-18 May 2018, hosted by Posiva.
The report can be downloaded here.
The sixth workshop was held at the IAEA in Vienna, Austria, from 22-25
October 2018, and the report can be downloaded here.