Working Group 1

Reference models for waste disposal

Aims• Develop reference modelling approaches and

reference cases for biosphere in the future on the basis of the BIOMASS approach

• Include environmental change in biosphere modelling– Climate, society, land use

• Set of models/cases that cover a wide range of environmental situations

Status of discussion• Definition phase• Biosphere modeling starts somewhere between the

waste in the repository and the human body• Discussion of the interface geosphere-biosphere• Agreement of 5 compartment that are assumed to

be initially contaminated due to discharges from the geophere – Well– Soil– Surface waters (lakes, rivers, sea)– Sediments (lakes, rivers, sea)

Processes involved in environmental transport

• Radionuclides enter biosphere via well– Drinking water (human, cattle)– Irrigation • (Contamination of soils / foliage)

– Uptake by plants– Accumulation in soil /speciation / migration / sorption /

desorption / fixation– Erosion / bioturbation

• Foliar contamination– Interception, weathering, translocation

– Uptake by domestic endpoints: meat, milk etc.– Ingestion, Inhalation, ext. exposure

Radionuclides enter biosphere via sediments• Processes in sediments

– Change of water levels– Sorption / desorption /speciation– Bioturbation / Resuspension to water column– Resuspension from dry sedimets

• Processes in water– Speciation– Uptake by biota

• Transfer to man– Drinking water (human, cattle)– Irrigation (Contamination of soils / foliage)– Uptake by domestic endpoints: meat, milk etc.– Ingestion, Inhalation, ext. exposure

Further issues to be discussed this week

• Continue discussion on relevant processes• Endpoints – Humans / biota (?)

• Find consensus on – Climates to be considered– Land use

• Agriculture /semi-natural / natural systems

– Human habits

• Interactions between biosphere and geosphere– e.g.: Climate -> hydrogeology -> capacity of wells– Pump rate of wells -> RN concentration in the groundwater

• How to proceed after this week