IAEAInternational Atomic Energy Agency

Kd Database

Proposal for the IAEA MODARIA II Programme (2016–2019)

Patrick Boyer (IRSN)

Miquel Vidal (University Barcelona)

Daniel Kaplan (Savannah River National Laboratory)

Brenda Howard (CEH)

IAEA

Underlying problem to be addressed by the proposal

• Problem: • Sensitivity analyses demonstrate that Kd values are the most important

source of uncertainty in risk calculations

• Need to make datasets more user friendly and enable to make informed selection of Kd values

• Need for technical justification for Kd selection

• As MODARIA I, we created critical review Kd datasets of soil and freshwater systems:

• 10,000 Kd entries >80 elements

• Derived Kd distributions (PDF/CDF)

• Developed examples of how to reduce uncertainty by identifying key properties

• Identified and developed protocol to fill data gaps

• Established a path forward to include marine Kd dataset

IAEA

Aims and Objectives

• Include marine Kd data (IAEA’s MARiS)

• Move towards a common structure for soil/freshwater/marine systems

• Increasingly important for global assessments

• To help users reduce Kd uncertainty through the use of environmental properties that are radionuclide-specific

– “smart” database

• Fill data gaps for prioritized radionuclides & scenarios

IAEA

Main working steps

1. Work with other WG to insure we meet their needs

2. Finalize software structure

3. Complete critical review of marine Kd

4. Import soil/freshwater/marine datasets into common database

5. Continue efforts to help user reduce uncertainty through identifying key factors

6. Develop procedure and make recommendations for missing data (mean & distribution)

IAEA

Expected results and benefits

• Kd database

• Critically reviewed mean and distribution

• Global soil/freshwater/marine

• Help to inform end user how to reduce uncertainty