1. Working Group 1 Reference models for waste disposal

2. 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

3. 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)

4. 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

5. 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

6. 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