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INTERNATIONAL ATOMIC ENERGY AGENCY
WAGRAMERSTRASSE 5, P.O. BOX 100, A-1400 VIENNA, AUSTRIA

FACSIMILE: (+43 1) 26007, TELEPHONE: (+43 1) 2600



- HIDRA -
The International Project

on
Human Intrusion in the context of

Disposal of RadioActive Waste

Scope, Objectives, Content and Work Programme


Version 0.2, October 2012

- HIDRA -
The International Project

on
Human Intrusion in the context of

Disposal of RadioActive Waste

Document History:

Version 0.1: Technical Meeting, 24-28 September 2012

Version 0.2: Update after Technical Meeting, 09 October 2012

CONTENTS

1 INTRODUCTION 1

2 BACKGROUND AND RATIONALE 1

3 PROJECT DESCRIPTION 2

3.1 OBJECTIVES 2

3.2 PROJECT SCOPE 3

3.3 PROJECT ORGANISATION 3

3.4 PARTICIPANTS 5

4 METHODOLOGIES AND INTEGRATION WITH THE SAFETY CASE 6

4.1 Methodology or Process Considerations 6

4.2 Integration with the Safety Case 8

4.2.1 Phase 0: Operational Period 8

4.2.2 Phase 1: Institutional Control 8

4.2.3 Phase 2: Post Institutional Control, Knowledge of Facility 8

4.2.4 Phase 3: Distant Future, Knowledge of Facility Hazard is Lost 9

5 TECHNICAL SCOPE OF INITIAL WORKING GROUPS 10

5.1 TECHNICAL FACTORS 10



5.1.1 Rationale 10

5.1.2 Objectives 11

5.1.3 Scope 11

5.1.4 Outcomes 12

5.1.5 Contribution of Participants 13

5.2 SOCIETAL FACTORS 13



5.2.1 Rationale 13

5.2.2 Objectives 14

5.2.3 Scope 14

5.2.4 Outcomes 15

5.2.5 Potential Links with other Working Groups 15

5.2.6 Contribution of Participants 16

5.3 DESIGN CONSIDERATIONS 16



5.3.1 Rationale 16

5.3.2 Objectives 17

5.3.3 Scope 17

5.3.4 Outcomes 19

5.3.5 Contribution of Participants 19

6 RESPONSIBILITIES, MEETINGS AND DELIVERABLES 19

6.1 RESPONSIBILITIES 19



6.1.1 The Coordinating Group 20

6.1.2 The IAEA Scientific Secretary 20

6.1.3 Working Groups 20

6.1.4 Chairperson and Co-Chair 20

6.2 MEETINGS 21

6.3 DELIVERABLES 21

Appendix: Tentative work plan for the future WG activities 23










1INTRODUCTION


The International Atomic Energy Agency (IAEA) has set out a framework of internationally agreed standards for nuclear safety, radiation protection, transport and radioactive waste disposal [1-3]. This document sets out the proposed content of a new IAEA project provisionally called HIDRA (Human Intrusion in the Context of Disposal of RadioActive Waste). This work plan reflects discussions in a Consultant’s meeting in March 2012 and a larger Technical Meeting involving representatives from more than 20 countries held in September 2012. The proposed activities will take place in the context of the IAEA current Safety Requirements and draft Guides for near-surface radioactive waste disposal [4, 5, 6, 7] and will be coordinated with activities related to the safety case being discussed in the PRISM and GEOSAF projects.

The IAEA has a statutory obligation to establish standards of safety for protection of health and minimization of danger to life and property, and to provide for the application of these standards (Article III of the IAEA Statute). The IAEA also has a statutory obligation to provide for exchange of information among its member states relating to the peaceful uses of atomic energy (Article VI). Projects such as HIDRA are one means of fulfilling the IAEA statutory obligations. The development of the safety standards is aided by having a degree of international consensus on the “what” and “how” of waste safetysomething that projects such as HIDRA work towards. HIDRA will inform the application of the IAEA safety standards by providing foundation material to clarify requirements related to human intrusion and to support expert missions, training events and peer reviews carried out under the IAEA’s Technical Cooperation Fund. Exchange of information among the member states is fostered by participating in the various HIDRA meetings and through dissemination of the products developed during the project.



The project will describe considerations for addressing future human actions in post-closure safety assessment of radioactive waste disposal and the use of those assessments to optimise siting, design and waste acceptance criteria within the context of a safety case. The intent is to, based on the common principles, requirements and recommendations from the IAEA, ICRP and OECD/NEA and experiences in Member States, identify and share information related to implementation of activities to meet those requirements.

2BACKGROUND AND RATIONALE


The aim of radioactive waste disposal is to increase the level of safety of the waste (sometimes this is referred to as a “safety index”). Containing the waste and removing it from the human environment, by burying it, rather than dispersing it in the environment increases its safety index and is generally accepted as the preferred approach for managing radioactive waste. When waste has been placed in a sealed underground or near-surface disposal facility, the intention is that there will be no further human contact with the waste. As a consequence, this approach results in concentrated sources of radioactive waste that are contained in one location, which can pose hazards in the future.
A safety case for a radioactive waste disposal facility needs to explain how the facility will provide long-term isolation of the waste from the human environment. As the future is uncertain, safety cases consider a range of different scenarios. These scenarios are not attempting to predict the future, but rather to illustrate possibilities that may, or may not, occur in the future. Some of the possible scenarios will be more likely to occur than others.
One aspect of the future that is particularly uncertain, over the timescales considered for radioactive waste disposal facilities, is how human society will evolve and what future human activities may take place in the location of the disposal facility. Therefore safety cases need to consider the possibility that in the future knowledge of the disposal facility location and the hazard it presents is lost and that future human actions may disturb the facility, e.g. by mining, drilling etc.
Currently, there is agreement that future human actions, especially inadvertent intrusion resulting in some disruption to the facility, must be considered in the safety assessment as part of the safety case for a radioactive waste disposal facility. However, there is no agreed international position on how to incorporate future human actions into safety assessment, siting and design. It is expected that a radioactive waste disposal facility should be sited and designed to reduce the likelihood and consequences of such “future human action” (FHA) scenarios, as far as possible.
There are many factors that can influence the potential impacts of inadvertent human intrusion. For example, the facility should be sited away from natural resources to minimise the chance of exploratory drilling or design features can be implemented to reduce the potential for, or consequences of, some form of direct contact with the waste. This project will address considerations associated with societal, technical and design aspects that influence the assessment of impacts of human intrusion. The role of assessments of future human actions in the context of the safety case will also be addressed as supporting information for the PRISM and GEOSAF projects and to provide clarification and support for requirements in existing IAEA Safety Requirements and Guides.

3PROJECT DESCRIPTION

3.1OBJECTIVES


The objectives of the project are to:

  • Share experience and practical considerations for development and regulatory oversight of assessments of impacts of future human actions, primarily human intrusion, in the context of the safety case during the lifecycle for a disposal facility

  • Provide specific information regarding technical, societal and design considerations to support development of a structured process or methodology for developing scenarios for site-specific application

  • Describe the role of assessments of future human actions for siting, design and development of waste acceptance criteria in the context of the safety case

  • Provide suggestions for communication strategies to describe the rationale for assessments of future human actions and for interpretation of the results of those assessment for the public

  • Provide recommendations for WASSC and RASSC, as appropriate, for clarification of existing IAEA requirements and guidance relevant to the assessment of future human actions and human intrusion.

3.2PROJECT SCOPE


The project will focus on future human actions, primarily inadvertent intrusion involving a disruption of the disposal facility, occurring post closure and following the loss of institutional control for a properly closed repository. The events are assumed to occur when active and passive institutional controls are lost. Factors that influence the timing of the loss of institution controls will also be addressed. Potential disruptions that may occur during operations or prior to loss of institutional control are not considered in this project, but are an area that needs to be addressed in the framework of a safety case.
The project will consider near surface and geologic radioactive waste disposal facilities, including Very Low Level Waste (VLLW) facilities, facilities for short- and/or long-lived Low Level and Intermediate Level Waste (L/ILW), facilities for High Level Waste (HLW), Spent Nuclear Fuel (SF), and boreholes.
The expectation is that the participants will provide experience from regulatory and implementation perspectives for facilities with a broad spectrum of designs, waste characteristics, regulatory frameworks and for differing levels of development of the radioactive waste management programme. The influence of these different considerations on regulatory and implementation aspects of addressing future human actions will be a key topic for the project.
The participants will address the technical, societal and design aspects that influence the assumptions made for assessments of human intrusion for differing sets of conditions, as identified above, and consider how these can be addressed in a structured methodology for scenario development. The role of assessments of future human actions for decision-making in the context of the safety case throughout the lifecycle of a disposal facility (e.g., siting, design, waste acceptance criteria) will also be addressed.


3.3PROJECT ORGANISATION


Development of the project started in March 2012 with a small Consultancy to prepare a rough position paper outlining potential concepts to be addressed by a larger working group. A Technical Meeting involving representatives from more than 20 countries was convened in September 2012. At the Technical Meeting, three primary Working Groups were established to address specific issues and a fourth Working Group is envisioned to address integration of the information in the context of applications as part of the safety case for a disposal facility.

The current plan is for three Working Groups to address the following specific areas of interest:



  • Technical Aspects

  • Societal Aspects

  • Design Aspects.

Examples of interfaces between those working groups are illustrated in Figure 1. The three specific Working Groups will also interface with a future Working Group that will be tasked with addressing the overall integration of the different aspects into a methodology for including human actions in the safety assessment, and also in decision making associated with the overall safety case.



Figure 1 Proposed working group topics.
This project will consider input from other international projects (e.g., BIOPROTA, MeSA, PAMINA) and international recommendation from OECD/NEA, ICRP, etc. It is expected that results from this project will be used as inputs for consideration in updates or clarification for IAEA Safety Requirements and Guides and the role within the safety case will also be used as supporting information for consideration in activities in the GEOSAF II and PRISM (and it successor) projects. These external interactions are illustrated in Figure 2.
It is anticipated that the project will continue for 2 years with the potential for an additional year. A two year project would involve two future plenary meetings, which will be organised and hosted by the IAEA. These meetings will play a pivotal role in presenting and discussing the scope, content and outcome of the project. At the Technical Meeting in Sept. 2012, the working groups established Terms of Reference that are documented in this report. In between annual plenary meetings, individual Working Group meetings may be held to make progress on specific Working Group activities review progress made, and plan subsequent activities. The final plenary will be used to present the results and reports from the project. A web site will be available to facilitate the exchange of information.


Figure 2 Links with other activities (IAEA Safety Standards, ICRP, EC, OECD/NEA).

3.4PARTICIPANTS


The project is open to professionals from Member States who undertake technical activities related to the safety of radioactive waste disposal facilities. They may be technical specialists in issues related to safety assessment or the safety case or they may be responsible for the management and operation or regulation of waste disposal facilities. Experience with technical, societal, and design aspects related to human intrusion would be beneficial for participation, but is not essential as project is also intended to serve as an informational forum.

Participants in the project will be expected to contribute to the project by taking an active part in plenary discussions and Working Group activities, including contributing to project reports. Participants will benefit from the exchange of information with experts from different countries. They should be prepared to report on national experience in addressing future human actions, especially human intrusion.


4METHODOLOGIES AND INTEGRATION WITH THE SAFETY CASE


Two key objectives for this project are to provide recommendations for a structured process or methodology for assessing the impacts associated with future human actions and for considering those impacts in the context of the safety case for a radioactive waste disposal facility. This information is expected to be the result of an integrating activity that will consider the specific information identified by the working groups. Each of the working groups will also make process or methodology-related recommendations in the context of their topical areas as well as identifying considerations important for integration in the context of the safety case.

4.1Methodology or Process Considerations


A well-defined approach that can be applied to establish site-and design-specific considerations for the assessment of future human actions will be a useful tool to support regulators and implementers in Member States to address IAEA requirements in a more consistent and structured manner. Flexibility in the approach to consider different disposal concepts, site conditions, regional habits, and level of development will be important to serve a broad range of Member State needs.
The draft position paper used as the starting point for discussions at the Technical Meeting in Sept. 2012 to plan this project included an initial concept for a methodology as a starting point (Figure 3). The methodology was structured around three key areas and needs to be refined to incorporate feedback obtained through the efforts of the working groups addressing those areas as described in Chapter 5.


Figure 3. Initial Rough Concept for Methodology from Draft Position Paper.

4.2Integration with the Safety Case


It can be helpful when discussing the role of future human actions in the context of the safety case to think of the life-cycle of a radioactive waste disposal facility as a storyline, divided into a number of phases with distinct features relating to the likelihood of future human actions. As already discussed, in the context of future human action scenarios for the safety case, it is generally accepted that it is only necessary to consider scenarios where any actions that disrupt the safety functions of the facility are undertaken without knowledge of the hazard presented by the disposal facility. We refer to such actions as being “inadvertent”. By definition, inadvertent human actions cannot occur whilst there is general knowledge of the whereabouts of the facility and the nature of its contents. Thus the level of knowledge of the facility is the key factor in defining the different phases of the safety case storyline.
An initial concept for a storyline is provided in the following sections. This concept is intended to provide a rough framework for a more detailed description. The specific descriptions and expectations for each time frame are expected to be modified as the project proceeds.

4.2.1Phase 0: Operational Period


This is the period during which the radioactive waste disposal facility is operational. It includes the time during which the facility is constructed and waste is emplaced and the time taken by the processes of backfilling, sealing and closing the facility. During this period there is human action at the facility, but it is planned and intentional and suitable protection will be in place for workers, who will be aware of the hazardous nature of the materials with which they are working. By definition, future human actions are excluded from this phase of the disposal facility life-cycle.

4.2.2Phase 1: Institutional Control


This is the period that starts with the closure and sealing of the facility and continues until institutional control of the facility and site is relinquished. During this phase, it is anticipated that the facility will be monitored and that there will be security in place at the site, preventing any unauthorised access. There will therefore be no possibility for any inadvertent human actions that could damage the safety functions of the facility.

4.2.3Phase 2: Post Institutional Control, Knowledge of Facility


This is defined as the period that starts immediately following cessation of institutional control and continues for as long as there is public knowledge of the site and the hazard it presents. It is anticipated that records will be maintained for any radioactive waste disposal facility at the local, national and international levels for many decades and even centuries (such timescales may be justified, for example, by considering the UK Doomsday Book created in the 11th century, documenting land use and locations of towns and villages, populations and livestock throughout England, which survives today).
Whilst such records are in place it can be considered that there can be no authorised inadvertent intrusion. It is perhaps possible that there could be minor, unauthorised inadvertent intrusion, for example small-scale digging without any consent, but no major construction or excavation activity that would require any form of planning consent or authorisation.

4.2.4Phase 3: Distant Future, Knowledge of Facility Hazard is Lost


This phase begins when there is no longer any public knowledge of the hazardous nature of the contents of the disposal facility. It may be possible that there is some knowledge of a feature at the disposal facility location, for example it may present a detectable signature on surface mapping techniques, but there is no knowledge of the potential hazard the facility presents.
In this phase there is the potential for inadvertent human intrusion into the disposal facility, or other human actions that could disrupt the safety functions of the disposal facility. Such activities could include drilling into the facility, mining or excavating to the depth of the wastes.
The likelihood of such actions will be determined by the depth of the facility, so it is reasonable to assume a much lower likelihood for intrusion into a deep geological facility than into a near-surface facility. Siting of the disposal facility away from any potential natural resources, such as water or minerals, will also reduce the likelihood of the facility being disturbed by exploratory drilling activities.
The consequence of such actions will depend on the:

  • nature of the waste, its level of radiotoxicity, i.e. how harmful it is;

  • timing of the intrusion event, noting that the further into the future the intrusion occurs, the greater the radioactive decay of the radionuclides in the wastes (although for certain radiotoxic radionuclides, such as radon-226, there will be ingrowth from the decay of parent radionuclides);

  • amount of waste that is brought into the biosphere;

  • nature of the intrusion scenario, i.e. how many people come into contact with the waste and for how long, whether radionuclides are ingested and/or inhaled and levels of exposure to external radiation.

This third phase is the phase most applicable to consideration of inadvertent future human actions that disturb the disposal facility.
When siting and designing a radioactive waste disposal facility, consideration should be given to reducing the likelihood of human intrusion scenarios. This could include:

  • selecting a site with a low history of drilling or mining;

  • increasing the depth of waste burial;

  • placing durable markers at the site to increase the length of time before Phase 3 can reasonably be expected to occur;

  • consideration of “diverting shields” above the waste so that a drill bit misses the waste (for example, the Yucca Mountain Project safety case took credit in this respect for the role of the titanium drip shields above the waste containers).

However, when considering design features that may make a disposal facility more robust to human intrusion scenarios, it is essential to consider the impact on other aspects of the safety case. For example, introducing additional metal to potentially “divert” a drill bit, could lead to the generation of additional gas which may lead to other, more likely, post-closure exposure pathways. It will be important not to reduce the overall robustness of the safety case in order to mitigate potential, hypothetical future human action scenarios.
Although discussion of future human actions in a safety case is likely to focus on Phase 3, the earlier phases should not be ignored, as discussion of the length of time during which inadvertent disruptive human actions can reasonably be assumed not to occur helps to build confidence in the safety case. In summary, the use of such a storyline helps to put discussion of future human action scenarios (which may be judged as low likelihood, high consequence scenarios) into an appropriate context.

5TECHNICAL SCOPE OF INITIAL WORKING GROUPS


As discussed in Section 3, it is envisaged that the objectives of the project will be realised through four main working groups:

  • Working Group 1: Technical Aspects.

  • Working Group 2: Societal Aspects.

  • Working Group 3: Design Aspects.

  • Integration Working Group (TBD, see conceptual discussion in Chapter 4).

The rationale, proposed scope and anticipated outcomes of each Working Group are outlined below. The lists of activities within each Working Group are not definitive. Alternative/additional activities can be added in the future or existing activities could be modified/removed, consistent with the overall objectives of the project.

Care will be taken that the project activities are consistent with IAEA documents, especially the Safety Guide on the safety case and Safety Assessment. The products from this project will potentially provide clarification of specific topics related to future human actions that are identified in Safety Requirements and Guides.


5.1TECHNICAL FACTORS

5.1.1Rationale


WG1 will discuss and identify scenarios for which human intrusion has been postulated to disrupt radioactive waste disposal systems. WG1 will consider the postulated ranges and consolidate the scenarios into general categories of scenarios that encompass reasonably expected end members. To support the overall effort, WG1 will focus on the technical criteria associated with future human intrusion events. Providing this information in a consolidated form will allow for a quick reference to provide high-level insights that may provide a starting point for developing future human intrusion analyses.
The group has used the following criteria to constrain the number of scenarios to an appropriate range to encompass reasonably expected general scenarios:

  • Implementation generally differs between countries, though some aspects may be represented in each. By grouping scenarios into general categories, key aspects related to human intrusion can be highlighted.

  • In general, the working group identified three methods of intrusion (which have subsets described later) defined by current practices that fall into the following categories:

    • Drilling

    • Excavation

    • Mining.



5.1.2Objectives


The objective of this effort is to support the development of the currently titled, draft “Position Paper on Future Human Actions at Disposal Sites.” Specifically, the objective is to provide a document that addresses the foci of WG1 identified above that would discuss the technical criteria related to potential scenarios of future human intrusion of radioactive waste disposal systems. This document may be in the form of a chapter of a future consolidated report. The specific objectives may require reassessment based on input from working groups two and three.

5.1.3Scope


During the plenary session, WG1 identified multiple potential methods of human intrusion (e.g., drilling, excavation). To limit the number of scenarios, WG1 identified cases that would provide reasonable upper and lower bounds for the scenarios considered, as opposed to the full number of possibilities. While additional scenarios were identified, these seven (sub) scenarios were identified as case studies:


  • Drilling (Near Surface Disposal)

    • Water resource

    • Mineral exploration

  • Excavation (Near Surface Disposal)

    • Residential

    • Roadway

  • Deep Geologic Disposal

    • Drilling

    • Mining

    • Solution Mining

WG1 identified that there may be future integration issues with the other Working Groups. An example would be that another working group would need technical information related to “markers” serving as passive institutional controls.



5.1.4Outcomes

The Technical Criteria Working Group will develop a draft document describing the technical criteria related to future human actions at radioactive waste disposal sites. To focus discussions in the draft document, future human actions have been discussed in a set of scenarios that generally represent the range of hypothetical human intrusion actions currently considered in the international community. The report will utilize expert experience, available literature related to the content of the report, and relevant international examples.


The tentative outline of the deliverable is provided below (note that the disposal system is assumed to be near surface unless otherwise indicated):


  1. Executive Summary

  1. Introduction

    1. Background

    2. Scope/Purpose

    3. Objectives

  2. Scenarios

    1. Introduction

    2. Methods

    3. Scenarios

    4. Drilling

      1. Water resource

      2. Mineral exploration

    5. Excavation

      1. Residential

      2. Roadway

    6. Deep Geologic Disposal

      1. Drilling

      2. Traditional Mining

      3. Dissolution Mining

  3. Comparison of Key Similarities and Differences

  4. Appendix – International Examples

As an example of the type of information to be included in the report, each scenario will address, to the extent possible:



  1. An overview of the scenario, include assumptions,

  2. Technical details related to the intrusion event and potential receptors,

  3. Potential impacts on the disposal system and environment,

  4. Potential consequences to the receptor,

  5. Mitigation strategies, and

  6. Conclusions.

WG1 will share appropriate information and drafts with the other members of WG1. As needed, WG1 will coordinate with Working Groups 2 and 3 to ensure consistency for the full draft report.



5.1.5Contribution of Participants

Participants in the Technical Criteria Working Group are expected to:




  • Review relevant international documents related to human intrusion.




  • Review and identify international examples of human intrusion that may be appropriate for incorporation.




  • Proactively share information resources with the working group members throughout the development of the draft report.




  • Contribute to the preparation, review and improvement of Working Group 1 documents.




  • Coordinate with working groups 2 and 3 as necessary.



5.2SOCIETAL FACTORS


One aspect of the future that is particularly uncertain, over the timescales considered for radioactive waste disposal facilities (for deep, near surface and land disposal), is how human society will evolve and what human activities may take place in the location of the radioactive waste disposal facility Therefore, safety cases need to consider the possibility that future knowledge of the site is lost and FHA may affect the radioactive disposal facility.
However, it is not clear how to incorporate FHA scenarios into the safety case as there are questions related to the description of such scenarios, the interpretation of the results and how to involve and communicate these results to stakeholders (for example probability). Therefore, in order to build methodologies for FHA scenarios, it is crucial to look at how to incorporate societal context. The relevance of the aforementioned scenarios depends on the understanding of the societal context for future human actions.

5.2.1Rationale


Working Group 2 is addressing the fact that no one is capable of predicting the certain future evolution, behaviour, and actions of humans. However, it is possible to describe different possible societal contexts. These descriptions can be useful tools when developing FHA scenarios and/or when building confidence in the safety of a radioactive waste disposal facility. The future human behaviour is dependent on societal aspects which is a combination of:


  • the lifestyle, motivations, moral, cultural and ethical values of the people (individuals and group),

  • the evolution of knowledge and technology

  • the institutions, whether they are operators, regulators, local, national or international organizations, or any other stakeholders that might arise in the future.

The societal context is deeply linked with the policies in force at the time where they are considered. Today, the societal context is obviously taken into account, even in informal ways, when building scenarios for safety cases.


An inescapable response of disposing of radioactive waste in repositories (to contain and isolate them) is a potential exposure in the event that someone could come into contact with this waste. However, the likelihood of FHA may be small and thus a high dose consequence of a FHA scenario does not necessarily mean that that the concept of radioactive waste disposal should be abandoned. In these cases societal aspects play a role in the interpretation of results and in communication of results with stakeholders.

5.2.2Objectives


The objectives of the Societal Aspects working group are to share, exchange information and communicate good practices on:


  • How societal aspects drive the generation of FHA scenarios that may eventually be considered in the safety case

  • How the use of FHA scenarios helps to build confidence in the overall safety of the radioactive disposal facility (including derivation of WAC) at all phases of its life cycle

  • How to preserve knowledge throughout the life cycle of the radioactive disposal facility

  • How to involve and communicate with stakeholders in the development and use of the safety case (aspects related to FHA).

5.2.3Scope


The main objective of Working Group 2, the Societal Aspects working group, is to share, exchange information and communicate how societal aspects could be incorporated into safety cases. The following issues were discussed starting with the working draft position paper prepared in March 2012 and may be addressed in the Societal Aspects working group:



  • Discuss what are the common assumptions? Give examples from different countries of how societal aspects are incorporated in FHA scenarios

  • Common understanding of assumptions - What level of development (both technological and societal, current vs future) should be taken into account when scenarios are developed?

  • Common understanding of assumptions - Considering the state of knowledge – what distinguishes inadvertent and advertent?

  • Preservation of knowledge - What strategies should be implemented to ensure information needs of future generation (e.g. international archives, monitoring)?

  • Preservation of knowledge - What types of passive controls can be effective in preventing inadvertent intrusion?

  • How can site selection criteria be used to look at FHA? Are there examples?

  • For what timeframe is the assessment applicable, i.e. for how long can one assume that knowledge of the disposal system is preventing inadvertent intrusion? Are there existing examples?

  • The probability of some types of intrusion may be assumed to be 1. What justifications (if any) are sufficient to consider probabilities less than 1?

  • Involving and communicating to stakeholders - The resulting doses of FHA analysis may be high whereas the likelihood of actually having an intrusion may be low. How should such results be communicated to stakeholders? Should stakeholders be involved in the process? If yes, at what stage? Are there other groups that are considering aspects associated with communicating with stakeholders (e.g., IAEA, NEA)?

  • What aspects of societal aspects should be included in the methodology of deriving FHA scenarios?

  • How can different scenarios of FHA be used in the process of siting and designing a repository, and developing WAC?

  • Think outside the “engineering” box!

5.2.4Outcomes


The Societal Aspects working group will prepare a report (or chapter of a report) that compiles information on how different societal aspects may be included in safety cases. In this report, consensus between Member States should be clearly identified where applicable, and areas where differences have been identified should be outlined. This report could be the basis for development of an IAEA TECDOC or a position paper.

5.2.5Potential Links with other Working Groups


The Societal Aspects working group has identified other projects and topics regarding safety cases were integration and information exchange may be valuable. Cooperation and information exchange are proposed with the following projects:


  • GEOSAF 2 – regarding our topic to considering how scenarios regarding future human actions are integrated into the safety case

  • PRISM – regarding our topic to considering how scenarios regarding future human actions are integrated into the safety case

  • IAEA siting documents

  • Other international stakeholder consultation groups, e.g. OECD/NEA Forum on Stakeholder Confidence (FSC) regarding communication of results and interpretation of FHA analysis.

  • Information preservation groups – working with information preservation could be contacted to discuss assumptions regarding how long knowledge of repository can be assumed, how to relate to archives etc.

5.2.6Contribution of Participants


Participants in the Societal Aspects working group are expected to:


  • Share experiences regarding future human actions analysis in their countries

  • Share success and challenges in using FHA scenarios in siting and designing a repository and in the of WAC

  • Provide reference information

  • Provide feedback to concerns that may be specific to the situation in their country

  • Contribute to preparation, review and improving of working group documents to elaborated in the course of the project.

5.3DESIGN CONSIDERATIONS

5.3.1Rationale


The treatment of FHA and human intrusion (HI) in the context of Safety Case development for radioactive waste disposal facilities needs adequate guidance due to uncertainties regarding future human activities and how human society will evolve, as well as due to uncertainties pertaining to potential future human activities that may take place at the disposal site. In this context, accepted and acknowledged technical as well as societal conditions and issues have to be addressed in the Safety Case.

The outcome of investigated technical and societal issues together with the underlying design of a specific disposal facility forms the basis for the development of HI scenarios, which have to be considered as plausible scenarios. The investigations of developed scenarios in turn, can provide information about the optimisation potential of the disposal system. Therefore the following task is quite vital for considering HI in a Safety Case:



  • Linking Technical and Societal Conditions with Design & Siting - to consider the synthesis of site and societal considerations with the actual repository design & siting to develop the full scenarios to be considered as plausible.”

In the context of siting and design aspects, the following items are of particular importance:

  • Timing – effectiveness of barriers as a function of time

  • Links between natural processes and intrusion (e.g.; erosion of cover)

  • Countermeasures – what types of barriers are effective against drilling or excavation (e.g.; need to develop a list of barriers and different types of potential intrusion)

  • How does design minimize impact / contact with any specific waste package (spatial issue)?



5.3.2Objectives


The overall objective of this effort is to support the development of the currently titled, draft “Position Paper on Future Human Actions at Disposal Sites.” Specifically, the objective is to provide a document that addresses the scope of work of WG3, identified above, that would discuss the siting and design aspects in the context of future human intrusion of radioactive waste disposal systems. This document may be in the form of a Chapter of a future consolidated report.

For implementation of the overall objective several other specific objectives have to be considered within the scope of WG3:



  • Cross-fertilization of knowledge, concepts and ideas among IAEA member states to strengthen the common understanding of HI issues.

  • Understand and assess

    • the significance and consequences of HI to the safety function

    • the interaction and relationship between siting / design and HI scenario assessment

  • Identify key measures and features to:

    • deter potential human intrusion

    • reduce HI consequences

The above mentioned specific objectives may require reassessment based on input from the other working groups.

5.3.3Scope


During the group meetings, WG3 identified siting / design aspects that might deter or prevent specific human actions at the site, including:

  • Design

  • Depth1 of waste disposal and depth of repository

  • Cover (near surface disposal)

  • Waste isolation / separation and containment

  • Container (material, wall thickness)

  • Vaults

  • Counter-measures (e.g., design features to deflect drill bits)

  • Backfill

  • Siting

  • Avoiding resources as much as possible

    • mineral resources

    • water (as a function of the quality and availability)

  • Avoiding dense population

  • Avoid archaeological and historical locations

  • Rough terrain (difficult to the reclamation of land).

In order to derive relevant siting and design aspects in a systematic way, it was decided to collect information, data, and facts of planned and existing facilities from the member countries for both near surface disposal and geological disposal as a starting basis for the further tasks. In this context an internal questionnaire with specific queries will be provided.

The future tasks pertain to the identification of:



  • Differences and commonalities between national programs (regulatory basis, disposal concepts etc.),

  • Components of the disposal system that can be impacted by HI,

  • Differences and commonalities between near surface and geological disposal systems, and

  • Measures and features that can be taken during the siting / design in order to deter and / or reduce consequences of HI,

  • Cross cutting issues and integration among groups.

    It is expected that the exchange of information between the WGs is an iterative process in terms of the derivation of HI scenarios, consideration of societal aspects and identification of countermeasures relating to siting / design aspects.





5.3.4Outcomes


The focus of WG3 will be on siting and design aspects in consideration of human intrusion. In this context different disposal facilities (e.g. near surface and deep geological disposal) have to be taken into account. There was general consensus that information of disposal facilities shall comprise natural and engineered barriers, safety-functions, performance time-frames, waste acceptance criteria (WAC) and kind of waste (e.g. LLW, ILW and / or HLW) etc. The collection of this information should establish the basis for the further tasks of WG3. It was also discussed that, in contrast to the deep geological disposal of HLW, near surface disposal facilities already exist. These facilities are in the construction phase, operational phase, closure phase, or post closure phase. Currently, it is uncertain how WG3 will deal with such existing facilities in terms of HI and the group does not anticipate “back fit” assumptions. Finally, the key conclusions of the basis work from WG3 will be derived.
The working group will share appropriate information and drafts with the other members of WG3. As needed, WG3 will coordinate with WG1 and WG2 to ensure consistency within the full draft report. The specific future interfaces between the WGs have to be defined.

5.3.5Contribution of Participants


Participants in the Design Considerations Working Group (WG3) are expected to:

  • Collect and exchange information (e.g., questionnaire) and experience gained on siting and design features that influence HI (all members)

  • Identify the relevant components of the disposal system that can be impacted by HI (B. Eid, U. Elghawi, F. Dragolici, C. Virtopeanu)

  • Identify differences and commonalities between national programs (B. Guiot, B. Eid, T. Beuth)

  • Identify differences and commonalities between near surface and geological disposal systems (J. de Meredieu, S. Lei, D. Cho)

  • Identify measures and features that can be taken during the siting / design in order to deter and reduce consequence of HI (M. Capouet, D. Cho, J. Walker, B. Guiot, M. Muneer)

  • Identify cross cutting issues and integration among groups (e.g.; overlapping issues pertaining to HI) (T. Beuth, B. Eid)

  • Derive key conclusions (T. Beuth, B. Eid).



6RESPONSIBILITIES, MEETINGS AND DELIVERABLES

6.1RESPONSIBILITIES


The organisation structure of the project includes a coordinating group comprising the IAEA Scientific Secretary, Chair, Co-Chair and Working Group Leaders. The roles are described below.

6.1.1The Coordinating Group


The Coordinating Group consists of a Chairperson, the coordinators of the Working Groups and the IAEA Scientific Secretary. Its role will be to coordinate the activities of the Working Groups, identify and solve issues of a technical and organisational nature that need to be resolved as part of the project, prepare and coordinate the topics, ensure consistence between Working Groups, agendas and summaries of the plenary and Working Groups meetings, and coordinate the preparation and review the documents and materials.

6.1.2The IAEA Scientific Secretary


The IAEA Scientific Secretary will provide coordination with the IAEA and technical and administrative assistance to the project. The Scientific Secretary will also make the necessary arrangements for planning, conducting plenary and other Working Group activities in accordance with the work plan, as well as for documentation of the proceedings of the meetings, Working Group activities and final outcomes of the project.

6.1.3Working Groups


Each Working Group will consist of a leader and a number of participants who will contribute actively to the work undertaken by the Working Group.

The Working Group will identify and discuss technical issues consistent with the project scope and develop a document reflecting the discussions in the working group. The working groups will function in parallel, but the plenary and Working Group meetings will be structured in such a way that participants can make contributions to the integrating group (TBD) and also directly participate in one of the working groups addressing specific topics.

The Working Group leads will be responsible for:


  • Coordinating the working group activities.

  • Overseeing preparation of the overall work plan of the working group activities.

  • Overseeing the preparing of the technical content of working group meetings.

  • Chairing the working group meetings.

  • Overseeing compliance with Working Group objectives.

6.1.4Chairperson and Co-Chair


The Chairperson and Co-Chair will have the responsibility of:

  • Leading the project.

  • Chairing the plenary and Coordinating Group meetings.

  • Reviewing technical report(s).

  • Overseeing consistency with the objectives and agreed work plan.

6.2MEETINGS


The following categories of meetings are envisaged:

  • Annual plenary meetings.

  • Working Group meetings, which would take place during the plenary meetings and at one (or potentially two) additional times per year.

  • Coordinating Group meetings.

The first plenary meeting will take place in November 2013. The plenary meetings provide project participants with the opportunity to exchange knowledge, experience and information on a range of issues relating to near-surface disposal either through giving an oral presentation or by providing a poster.

6.3DELIVERABLES


It is envisaged that the following deliverables would be produced:

  • A project report based on the working group reports.

  • A booklet, suitable for project managers, describing the role of future human action for decision-making in the context of the safety case and to provide assistance communicating the purpose of assessments of future human actions.

These documents will provide a discussion of good practice in the technical areas addressed by the project.





REFERENCES

[1] INTERNATIONAL ATOMIC ENERGY AGENCY. The Principles of Radioactive Waste Management. Safety Fundamentals, Safety Series No. 111-F, Vienna, 1995.

[2] INTERNATIONAL ATOMIC ENERGY AGENCY. Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management. Vienna, 1999.

[3] INTERNATIONAL ATOMIC ENERGY AGENCY, Fundamental Safety Principles. 2006, International Atomic Energy Agency, Vienna, Austria.

[4] INTERNATIONAL ATOMIC ENERGY AGENCY. Geologic Disposal of Radioactive Waste, Specific Safety Guide No. SSG-14, International Atomic Energy Agency, Vienna, 2011.

[5] INTERNATIONAL ATOMIC ENERGY AGENCY. Near Surface Disposal of Radioactive Waste, Draft Safety Guide DS 356, International Atomic Energy Agency, Vienna, 2012.

[6] INTERNATIONAL ATOMIC ENERGY AGENCY. Disposal of Radioactive Waste, Specific Safety Requirements, Safety Series No. SSR-5, International Atomic Energy Agency, Vienna, 2011.

[7] INTERNATIONAL ATOMIC ENERGY AGENCY. The Safety Case and Safety Assessment for Disposal or Radioactive Waste, Draft Safety Guide DS 355, International Atomic Energy Agency, Vienna, 2011.





Appendix: Tentative work plan for the future WG activities



WG 1

The draft outline and the draft technical input needs were identified during the Technical Meeting in Sept. 2012. WG1 assignments were made and the members are expected to provide their inputs to the lead author. Prior to the next plenary meeting, the lead author will consolidate the draft inputs and provide, for comment, to the WG1 members. As necessary, the lead author will coordinate with the group members to resolve any issues. If needed, a WG1 meeting may be called. Once any potential issues have been addressed, the lead author will provide a draft to the leads for working groups two and three, for comment. WG1 plans to have a document meeting the program description for WG1, noting that the scope of the currently titled, draft “Position Paper on Future Human Actions at Disposal Sites” may evolve as the other working groups develop their input. More specific details are provided below.


Timeline

Draft inputs from the WG 1 members December 2012

Consolidated draft report for WG1 member review February 2013

Revised draft report for WG2/3 lead review July 2013

Revised draft report for next Plenary September 2013

WG 2

During the Technical Meeting in Sept. 2012, WG2:

• Identified the objectives

• Discussed the issues identified as the scope

• Prepared draft text on the discussed issues

Prior to the Coordinate Group meeting in March 2013, WG2 will:

• Combine the different texts produced by working group members during the meeting into one draft document. This draft document may be used as the basis for a Chapter on Societal Aspects that will be the printed in the resulting report of the project (Eva by October 5)

• Distribute the draft document to the work group members for comments (everyone in Societal Aspects working group by end of November)

• Update the draft after getting comments from working group members and distribute to working groups 1 and 3 for their comment (Eva - December)

Prior to the Plenary meeting in 2013, the following activities will be conducted:

• Identify sources of information (people or organizations that could be consulted)

• GEOSAF 2 (Michael, Sucipta)

• PRISM (Andrey, Nataliya)

• IAEA siting documents (Julie, Maria)

• Other international stakeholder consultation groups, e.g. NEA FSC (Maria)

• Information preservation groups (Attila, Eva)

• Identify additional topics that should be covered (everyone)

• Collect examples that could be used in the description (Cecile, everyone)

Prior to the Plenary meeting in 2014, the following activities will be conducted:

• Continued expansion on examples and references

• Continued development of the text of the report chapter

Following the Plenary meeting in 2014, the final version of the report chapter will be completed.


In between the plenary meetings, one Working Group meeting may be held with some of the Working Group members in order to work on the draft report chapter and prepare the work for plenary meeting.
WG 3

The following tentative schedule comprises the tasks and outcomes of WG3 until the next plenary meeting:


Draft inputs from the WG3 members (until December 2012)

  • Collect and exchange information and experience gained on siting and design features that influence HI (all members)

  • Preparation of a questionnaire with the focus on disposal facilities (T. Beuth)

  • Responses to the questionnaire (all members)

  • Review of the responses

        • Identify the relevant components of the disposal system that can be impacted by HI (B. Eid, U. Elghawi, F. Dragolici, C. Virtopeanu)

        • Identify differences and commonalities between national programs (B. Guiot, B. Eid, T. Beuth)

        • Identify differences and commonalities between near surface and geological disposal systems (J. de Meredieu, S. Lei, D. Cho)


Preparation of a draft report for WG3 member review (until February 2013)

  • Compilation of the outcome from the review of responses



    Coordinate Group meeting (March 2013)

(Ongoing work)

  • Identify measures and features that can be taken during the siting / design in order to deter and reduce consequence of HI (M. Capouet, D. Cho, J. Walker, B. Guiot, M. Muneer)

  • Identify cross cutting issues and integration among groups (e.g.; overlapping issues pertaining to HI) (T. Beuth, B. Eid)

  • Derive key conclusions (T. Beuth, B. Eid)

  • Continued development of the text of the report chapter

(Revised draft report for)



  • WG3 member review (until June 2013)

  • WG1/2 lead review (until August 2013)

  • next Plenary (until October 2013)



Plenary Meeting (November 2013)


1 The depth of the repository as a mean to deter intrusion should be taken into account during the siting while selecting the appropriate host rock as well as during the design while selecting the actual emplacement of the repository within the geological formation.

REF. xxxxxxxx



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