MODARIA II: WORKING GROUP 6 BIOSPHERE MODELLING FOR LONG-TERM SAFETY - - PowerPoint PPT Presentation

MODARIA II: WORKING GROUP 6

BIOSPHERE MODELLING FOR LONG-TERM SAFETY ASSESSMENTS OF RADIOACTIVE WASTE DISPOSAL FACILITIES

IAEA review and enhancement of Biomass methodology

Cartoon of the proposed KBS-3 repository at Forsmark, Sweden

Vienna, 21 – 24 October 2019

MODARIA II: WORKING GROUP 6

BIOSPHERE MODELLING FOR LONG-TERM SAFETY ASSESSMENTS OF RADIOACTIVE WASTE DISPOSAL FACILITIES

IAEA review and enhancement of Biomass methodology

Cartoon of the proposed KBS-3 repository at Forsmark, Sweden

Vienna, 21 – 24 October 2019

Outline

• Background
• Key enhancement areas
• Current status of enhanced report

BIOMASS Background

• BIOMOVS II (1991-1996)

– Developed “Reference Biospheres Methodology” – International “Reference” models inappropriate – Instead: methodology and FEP list to encourage transparency, consensus and harmonisation

• IAEA BIOMASS (1996-2001)

– Theme 1 further developed and refined the methodology – Acknowledged there was further work to do

BIOMASS Background

• BIOMASS methodology has proved very useful

– Highlights systematic and transparent approach – Providing guidance that is adapted to each case

• Wealth of experience in intervening time

– Further international collaborations – Experience from examples of practical application – Developments in context of assessments – Scientific developments

WG6 Meetings

• Meetings:

– 20-22 April 2016, Brussels – 31 October-3 November 2016, Vienna – 10-12 May 2017, Brugg – 30 October – 3 November 2017, Vienna – 16-18 May 2018, Kerava – 22-25 October 2018, Vienna – 15-17 May 2019, Munich – 21-24 October 2019, Vienna

• Field trip to periglacial analogue
• Extensive collaborative work

– Close to 80 participants – Over 100 presentations – Close to 300 pages of workshop reports

Contributors and Organisations

• BIOPROTA project

– Progress only possible with support of the sponsors of the BIOPROTA project

• ANDRA, BfS, DSA, ENSI, FANC, LLWR, Nagra, NUMO,

NWMO, Posiva, RWM, SKB, SSM

– BIOPROTA Technical Support Team

• Support to facilitation and reporting of workshops
• Support drafting of updated guidance

Original BIOMASS Methodology

A. Setting down the assessment context Output: The underlying premises of the calculation (what is being calculated and why) are stated explicitly. B. Identification and justification of biosphere system(s) Output: Biosphere system, or a series of biosphere systems, identified by the principal component types, e.g. climate, topography etc. C. Biosphere system description Outputs: A word picture that provides qualitative and, where appropriate, quantitative description of the biosphere system. A description of potential exposure pathways. D. Consideration of potentially exposed groups Outputs: A list of candidate critical groups and/or other groups of special interest, where appropriate. Fully characterised exposure groups. E. Model development Output: Assessment model. F. Calculation Output: Doses or concentrations as required by the assessment context. FEP list and screening Principles for identification of biosphere systems Principles for critical group selection Data selection principles

Refinements Identified

Assessment Context Biosphere system identification and justification Biosphere system descriptions Human actions, wildlife Potentially exposed group definition human PEGs and wildlife PEPs Biosphere and supporting model definition Conceptual model, mathematical model & data FEP list and screening Site under- standing Data and model selection principles

Climate development & downscaling Geosphere (discharge locations) Near-surface investigation methods and experience Landscape development Principles for critical group selection Protection of the environment Confidence building

Calculation & communication

Enhanced Methodology

• Recognise

importance of methodology diagram

• Want to emphasise

importance of

– Site understanding: “Let the site tell the story” – Integration with

• verall safety

assessment and safety case – Degree of iteration and interaction

Report Structure

Key enhancement areas

Integration with Safety Case

Integration with Safety Case

Biosphere Narrative v Description

Biosphere Narrative v Description

• Clarification of

narrative versus description of the biosphere

• Bridges gap with

MODARIA I WG6

• Climate dynamics over

the next few thousand years proposed for MODARIA III

Use of Site Information

Use of Site Information

• Site information collected for many purposes

– Site characterisationis required for facility design, operational impact assessment, environmental impact assessment and post-closure safety assessment. – Highlights the importance of the dialogue between biosphere assessment and system understanding

Biosphere System

• Deciding how to

represent the biosphere in assessments

PEGs and PEPs

• Guidance on Potential Exposure Groups

– Characteristics – Behaviour

• Guidance on Biota Potentially Exposed

Populations

– Selection principles – Representation in a spatial context

Information Boxes

• Used to provide more detailed guidance on

particular topics

Data Selection Principles

• Only minor

changes

System Understanding

• Various approaches
• Interaction matrices for system understanding

and conceptual model development

Conceptual and Mathematical Models

Conceptual and Mathematical Models

Mathematical Representation

• Increased transparency of mapping

conceptual to mathematical model

Current status and plan to print

• Completed report

– Concise methodology ready – Final draft in IAEA template ready – Final review and approval until mid November – IAEA review and printing 2020 (?)

• Supplementary information

under development

– BIOPROTA report 2020

• So, its too late to join us!

…but maybe during next Programme?

Potential papers from Working Group 6

• IAEA guidance on climate and landscape change as an input to

defining biosphere characteristics for post-closure biosphere assessments of repositories for radioactive wastes (Paper)

• Approaches to the definition of potentially exposed groups and

potentially exposed populations of biota in the context of solid radioactive waste disposal (Paper)

• The updated BIOMASS methodology as illustrated by approaches

adopted in various assessments (Review)

• A roadmap of research and development requirements to

support applications of the updated BIOMASS methodology (Paper/Opinion)

MODARIA II: WORKING GROUP 6

BIOSPHERE MODELLING FOR LONG-TERM SAFETY ASSESSMENTS OF RADIOACTIVE WASTE DISPOSAL FACILITIES

IAEA review and enhancement of Biomass methodology

Cartoon of the proposed KBS-3 repository at Forsmark, Sweden

Vienna, 21 – 24 October 2019

Thank you!