Development and comparison of five site-specific biosphere models for safety assessment of radioactive waste disposal

Abstract

This paper describes the development and application of site-specific biosphere models that might be used for assessment of potential exposures in the framework of performance assessment studies of nuclear waste disposals. Model development follows the Reference Biosphere Methodology that has been set up in the framework of the BIOMASS study. In this paper, the application is to real sites at five European locations for which environmental and agricultural conditions have been described and characterised. For each of the sites a biosphere model has been developed specifically assuming a release of radionuclides to waters that are used by humans, for example as drinking water for humans and cattle and as irrigation water. Among the ingestion pathways, the intakes of drinking water, cereals, leafy vegetables, potatoes, milk, beef and freshwater fish are included in all models. Annual individual doses were calculated, and uncertainties in the results were estimated by means of stochastic calculations. To enable a comparison, all results were normalised to an activity concentration in groundwater of 1 Bq m(-3) for each of the radionuclides considered ((36)Cl, (79)Se, (99)Tc, (129)I, (135)Cs, (226)Ra, (231)Pa, (230)Th, (237)Np, (239)Pu, and (238)U), i.e. those that are usually most relevant in performance assessment studies of nuclear waste disposals. Although the results do not give answers in absolute terms on potential future exposures, they indicate the spectrum of exposures that might occur in different environments and specify the interaction of environmental conditions, human habits and potential exposure.

Environmental Chemical Contaminants in Food: Review of a Global Problem

“…Risk assessments are conducted to ensure that levels remain within acceptable limits. Furthermore, experimental models are undertaken to assess safety in ingestion pathways, considering several different food intakes [107]. In the US, there is an FDA rule pertaining to uranium, radium, alpha particle, beta particle, and photon radioactivity in bottled water [108].…”

Application of a generic biosphere model for dose assessments to five European sites

“…Human activities are also included in order to identify the important exposure pathways and critical groups. In order to be generic and useful for a broad range of biospheres, the proposed 'generic biosphere model' must at least take account of all the important features, events and processes (FEPs) and the exposure pathways identified in the sites studied in BIOMOSA (Pröhl et al 2004(Pröhl et al , 2005. Five sites, which covered a wide range of biosphere conditions in Europe, were selected for the BIOMOSA study.…”

“…BIOMOSA was completed in 2003 at the same time as a complementary EC BIOCLIM project (modelling sequential BIOsphere systems under CLIMate change for radioactive waste disposal) (Texier et al 2003) on assessing the long-term impacts on the safety of radioactive waste repositories due to climate and environmental change. The main report summarising the BIOMOSA work has been produced (Pröhl et al 2004).…”

“…The aim is to highlight the common approach to, or differences in, modelling the exposures that might occur due to different environmental conditions, human habits, and socio-economic development. Two companion papers describe the development and application of the site-specific models (Pröhl et al 2005, Olyslaegers et al 2005 and the results of the uncertainty analysis using the site-specific models, respectively.…”

Modeling the impact of climate change in Germany with biosphere models for long-term safety assessment of nuclear waste repositories

“…The BIOMOSA project assessed the influence of climate on the exposure of a hypothetical population with modeling approaches from different countries Pröhl et al, 2005). Other projects evaluated the influence of the evolution of geological, geographical or climatic conditions on the exposure of a population at a specific potential repository site (Posiva, 2010;SKB, 2011;Smith and Kozak, 2011).…”