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POSIVA 2014-03

January 2014

POSIVA OY

Olki luoto

FI-27160 EURAJOKI, F INLAND

Phone (02) 8372 31 (nat. ) , (+358-2-) 8372 31 ( int. )

Fax (02) 8372 3809 (nat. ) , (+358-2-) 8372 3809 ( int. )

Posiva Oy

Safety Case for the Disposal of Spent Nuclear Fuel at Olkiluoto

FEP Screening and Processing

ISBN 978-951-652-241-1ISSN 1239-3096

Tekijä(t) – Author(s)

Posiva Oy

Toimeksiantaja(t) – Commissioned by

Posiva Oy Nimeke – Title

SAFETY CASE FOR THE DISPOSAL OF SPENT NUCLEAR FUEL AT OLKILUOTO FEP SCREENING AND PROCESSING Tiivistelmä – Abstract

TURVA-2012 is Posiva’s safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. This report presents and applies the methodology by which Posiva’s TURVA-2012 FEP list − as described in Features, Events and Processes and used in Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of Radionuclide Release Scenarios for the Repository System, Biosphere Assessment and Models and Data for the Repository System − is shown to be as comprehensive as necessary at the current stage of the spent nuclear fuel management programme. The main part of the work, i.e. screening methodology and processing of the selected FEPs, has been conducted within earlier safety assessments, and has been applied to TURVA-2012 and to previous safety assessments, but never formally presented before this report. A full screening of Nuclear Energy Agency 2.1 FEP database is carried out again for this report and reported in detail to confirm the comprehensiveness of the TURVA-2012 FEP list. Except for the first stages of the screening process, surface environment FEPs are, however, not considered in this report.

Avainsanat - Keywords

FEPs, screening, disposal system, regulatory framework, assessment, scenario driver.

ISBN

ISBN 978-951-652-241-1 ISSN

ISSN 1239-3096 Sivumäärä – Number of pages

148 Kieli – Language

English

Posiva-raportti – Posiva Report Posiva Oy Olkiluoto FI-27160 EURAJOKI, FINLAND Puh. 02-8372 (31) – Int. Tel. +358 2 8372 (31)

Raportin tunnus – Report code

POSIVA 2014-03

Julkaisuaika – Date

January 2014

Tekijä(t) – Author(s)

Posiva Oy

Toimeksiantaja(t) – Commissioned by

Posiva Oy Nimeke – Title

TURVALLISUUSPERUSTELU KÄYTETYN YDINPOLTTOAINEEN LOPPUSIJOITUKSELLE OLKILUODOSSA - FEPIEN VALINTA JA PROSESSOINTI

Tiivistelmä – Abstract

Posivan rakentamislupahakemukseen liittyen tuotettu PSAR (Preliminary Safety Analysis Report) -raportti perustuu osaltaan TURVA-2012-pitkäaikaisturvallisuusperusteluun, joka on tehty käy-tetyn ydinpolttoaineen loppusijoitusta varten Olkiluodon kallioperään rakennettavalle loppu-sijoituslaitokselle. Tässä raportissa esitetään metodologia, joka on ollut käytössä FEP-listan (ilmiöt, tapahtumat ja prosessit) muodostamisessa TURVA-2012-turvallisuusperustelua varten. TURVA-2012:n FEP-lista on kuvattu tarkemmin raportissa Features, Events and Processes. FEP-listan käyttö turvallisuusperustelussa on kuvattu raporteissa Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of Radionuclide Release Scenarios for the Repository System, Biosphere Assessment sekä Models and Data for the Repository System. Tämän raportin tarkoitus on kuvata FEPien valinta ja prosessointi turvallisuusperustelua varten ja osoittaa että TURVA-2012:n FEP-lista on riittävän kattava ja vastaa käytetyn polttoaineen loppusijoitusohjelmassa meneillään olevan vaiheen tarpeita. Tässä raportissa esitetyn työn pääosa koskee FEP-valintaprosessin metodologiaa, joka on ollut käytössä myös turvallisuusarvioiden aiemmissa vaiheissa ja jota on käytetty myös muodos-tettaessa TURVA-2012:n FEP-listaa. Tätä metodologiaa ja prosessointia ei ole kuitenkaan aiemmin järjestelmällisesti kuvattu. FEPien valinnan pohjana on käytetty NEAn (Nuclear Energy Agency) 2.1 FEP-tietokantaa. Tässä raportissa esitetään FEPien valinta ja prosessointi, minkä perusteella on tarkasteltu TURVA-2012:n FEP-listan kattavuutta. Lukuun ottamatta FEPien valintaprosessin alkuvaihetta, pintaympäristön FEPit eivät ole mukana lopullisessa tarkastelussa.

Avainsanat - Keywords

FEPit, loppusijoitusjärjestelmä, viranomaisvaatimukset, turvallisuusarvio.

ISBN

ISBN 978-951-652-241-1 ISSN

ISSN 1239-3096 Sivumäärä – Number of pages

148 Kieli – Language

Englanti

Posiva-raportti – Posiva Report Posiva Oy Olkiluoto FI-27160 EURAJOKI, FINLAND Puh. 02-8372 (31) – Int. Tel. +358 2 8372 (31)

Raportin tunnus – Report code

POSIVA 2014-03

Julkaisuaika – Date

Tammikuu 2014

1

TABLE OF CONTENTS

ABSTRACT TIIVISTELMÄ

TERMS AND ABBREVIATIONS ..................................................................................... 3

FOREWORD .................................................................................................................. 5

1 INTRODUCTION ................................................................................................... 7 1.1 Background .................................................................................................. 7 1.2 The KBS-3 method ....................................................................................... 7 1.3 Posiva’s programme for developing a KBS-3 repository at Olkiluoto ........... 8 1.4 Regulatory context for the management of spent nuclear fuel ................... 11 1.5 Safety concept and safety functions .......................................................... 11 1.6 TURVA-2012 Safety Case portfolio ........................................................... 15 1.7 Quality assurance ...................................................................................... 17 1.8 Scope and objectives of the present report ................................................ 19 1.9 Structure ..................................................................................................... 19

2 METHODOLOGY FOR FEP SCREENING AND PROCESSING ........................ 21 2.1 Overall methodology .................................................................................. 21 2.2 FEP screening and processing steps ......................................................... 22 2.3 Identification and screening of FEPs for potential significance .................. 22

2.3.1 The initial FEP list ............................................................................. 22 2.3.2 Relevance screening ........................................................................ 22 2.3.3 Initial aggregation and component-wise classification of the FEPs .. 23 2.3.4 Significance screening ...................................................................... 23

2.4 Mapping remaining Project FEPs to the TURVA-2012 FEP list ................. 24 2.5 Cross-checking .......................................................................................... 24

3 SCREENING AND PROCESSING OF THE FEPS ............................................. 25 3.1 FEP lists included in the work .................................................................... 25 3.2 Relevance screening results ...................................................................... 25 3.3 Preliminary aggregation of FEPs and classification under disposal system

components ................................................................................................ 25 3.4 Significance screening results .................................................................... 26

4 MAPPING REMAINING PROJECT FEPS TO THE TURVA-2012 FEP LIST ..... 27

5 CROSS-CHECKING AGAINST OTHER RELEVANT FEP SOURCES .............. 29 5.1 Cross-checking against the Swedish SR-Site ............................................ 29 5.2 Cross-checking against the Canadian Fourth Case Study ........................ 32 5.3 Comparison with FEPs in Process Report 2007-12 ................................... 34

6 CONCLUSIONS AND THE WAY FORWARD ..................................................... 37 6.1 Comprehensiveness of TURVA-2012 FEP list ........................................... 37 6.2 The way forward ......................................................................................... 37

REFERENCES ............................................................................................................. 39

APPENDIX A. FULL TURVA-2012 FEP LIST .............................................................. 43

APPENDIX B. MAPPING OF THE TURVA-2012 FEPS TO NEA FEPS AFTER SCREENING PROCESS .................................................................................... 49

APPENDIX C. CROSS-CHECK AGAINST SR-SITE ................................................. 111

APPENDIX D. CROSS-CHECK AGAINST THE FOURTH CASE STUDY ................ 137

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TERMS AND ABBREVIATIONS

CLA Construction Licence Application.

DiP (Government) Decision-in-Principle.

EBS

EPM

Engineered Barrier System, which includes canister, buffer, back-fill and closure.

Equivalent Porous Medium.

FEPs Features, Events and Processes.

GD Government Decree.

IAEA International Atomic Energy Agency.

ISAM Integrated Safety Assessment Methodology.

KBS-3 An abbreviation of kärnbränslesäkerhet (nuclear fuel safety) ver-sion 3. The KBS-3 method for implementing the spent nuclear fuel disposal concept based on multiple barriers.

KBS-3H (Kärnbränslesäkerhet 3-Horisontell). Design alternative of the KBS-3 method in which several spent nuclear fuel canisters are emplaced horizontally in each deposition drift.

KBS-3V (Kärnbränslesäkerhet 3-Vertikal). The reference design alternative of the KBS-3 method, in which the spent nuclear fuel canisters are emplaced in individual vertical deposition holes.

KTM Finnish Ministry of Trade and Industry.

NDT Non-Destructive Testing.

NEA Nuclear Energy Agency.

NWMO Nuclear Waste Management Organization (in Canada).

OL3 Olkiluoto 3 reactor.

OL4 Fourth reactor to be constructed at Olkiluoto. Expected to be simi-lar to OL3 in TURVA-2012 safety case.

ONKALO Underground research facility constructed at Olkiluoto.

OSD Olkiluoto Site Descriptive model.

POTTI Database at Posiva with site-investigation data.

PSAR Preliminary Safety Analysis Report – a part of the construction licence application.

QA Quality Assurance.

QC Quality Coordinator; Quality Control.

R1 Relevance screening criterion 1. The Project FEP is defined by a heading without any description of what is meant by the heading.

R2 Relevance screening criterion 2. The Project FEP is related to as-sessment methodology. These FEPs are handled elsewhere in the TURVA-2012 safety case.

R3 Relevance screening criterion 3. The Project FEP is not relevant for the context of the TURVA-2012 safety case, especially in re-spect to the national regulatory requirements and guidelines.

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R4 Relevance screening criterion 4. The Project FEP is not relevant for the KBS-3V type repository design for spent nuclear fuel dis-posal.

R5 Relevance screening criterion 5. The Project FEP is not relevant for the present-day Olkiluoto site characteristics and likely future site characteristics evolving in response to climatic changes and other external factors.

Repository

system

Spent nuclear fuel, canister, buffer, backfill (deposition tunnel backfill + deposition tunnel end plug), closure components and host rock. Excludes the surface environment.

RSC Rock Suitability Classification. The aim of the RSC is to define suitable rock volumes for the repository, deposition tunnels and deposition holes.

RTD Research, Technical development and Design.

S1 Significance screening criterion 1. The FEP has insignificant im-pact on safety functions and radiation protection criteria.

S2 Significance screening criterion 2. The FEP has low probability to occur and low impact on safety functions and radiation protection criteria.

S3 Significance screening criterion 3. The FEP itself has considerably more serious consequences than any potential radiological conse-quences from the spent nuclear fuel.

SAFCA Safety Case project.

SKB Swedish Nuclear Fuel and Waste Management Company.

SR-Site SR-Site safety assessment for a repository in Forsmark.

STUK Finnish Radiation and Nuclear Safety Authority.

TEM Finnish Ministry of Employment and the Economy, previously Ministry of Trade and Industry (KTM).

TKS-2009 Finnish equivalent for RTD (see RTD). RTD programme for 2010−2012.

TURVA-2012 Posiva’s safety case supporting the construction licence applica-tion submitted in 2012 for the Olkiluoto spent nuclear fuel dis-posal facility. TURVA means safety.

VAHA Requirements management system at Posiva.

VVER-440 Pressurised water reactor type at Loviisa.

YJH Finnish abbreviation for Nuclear Waste Management.

YVL STUK’s (see STUK) regulatory guide series for nuclear facilities.

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FOREWORD

The participants in the project group for screening in/out discussions in this report are listed below:

Hagros, Annika (Saanio & Riekkola, SROY)

Hellä, Pirjo (SROY)

Hjerpe, Thomas (Facilia AB)

Pitkänen, Petteri (Posiva Oy)

Koskinen, Lasse (Posiva Oy)

Laine, Heini (SROY)

Marcos, Nuria (SROY)

Pastina, Barbara (SROY)

Snellman, Margit (SROY)

The review comments by Kristina Skagius (SKB) are gratefully acknowledged.

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1 INTRODUCTION

1.1 Background

On assignment by its owners, Fortum Oyj and Teollisuuden Voima Oyj, Posiva Oy will manage the disposal of spent nuclear fuel from the Loviisa and Olkiluoto nuclear power plants. At Loviisa, two pressurised water reactors (VVER-440) are in operation; at Olkiluoto, two boiling water reactors are operating and one pressurised water reactor is under construction. Plans exist also for a fourth nuclear power unit at Olkiluoto. At both sites there are facilities available for intermediate storage of the spent nuclear fuel be-fore disposal.

In 2001, the Parliament of Finland endorsed a Decision-in-Principle (DiP) whereby the spent nuclear fuel generated during the operational lives of the operating Loviisa and Olkiluoto reactors will be disposed of in a geological repository at Olkiluoto. This first DiP allowed for the disposal of a maximum amount of spent nuclear fuel corresponding to 6500 tonnes of uranium (tU) initially loaded into the reactors. Subsequently, addi-tional DiPs were issued in 2002 and 2010 allowing extension of the repository (up to 9000 tU) to also accommodate spent nuclear fuel from the operations of the OL3 reactor and the planned OL4 reactor. OL4 spent nuclear fuel is handled in the TURVA-2012 safety case assuming it to be similar to OL3 spent nuclear fuel.

1.2 The KBS-3 method

The 2001 DiP states that disposal of spent nuclear fuel shall take place in a geological repository at the Olkiluoto site, developed according to the KBS-3 method. In the KBS-3 method, spent nuclear fuel encapsulated in water-tight and gas-tight sealed me-tallic canisters with a mechanical load-bearing insert is emplaced deep underground in a geological repository constructed in the bedrock. According to the DiP, the repository shall be located at minimum depth of 400 m. In Posiva’s current repository design, the repository is constructed on a single level and the floor of the deposition tunnels is at a depth of 400−450 m in the Olkiluoto bedrock.

Posiva’s reference design in the construction licence application is based on vertical emplacement of the spent nuclear fuel canisters (KBS-3V; Figure 1-1). Currently, an alternative horizontal emplacement design (KBS-3H) is being jointly developed by the Swedish Nuclear Fuel and Waste Management Company (SKB) and Posiva.

The KBS-3V design is based on a multi-barrier principle in which copper-iron canisters containing spent nuclear fuel are emplaced vertically in individual deposition holes bored in the floors of the deposition tunnels (see inset in Figure 1-1). The canisters are to be surrounded by a swelling clay buffer material that separates them from the bed-rock. The deposition tunnels and the central tunnels and the other underground openings are to be backfilled with materials of low permeability.

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Figure 1-1. Schematic presentation of the KBS-3V design.

1.3 Posiva’s programme for developing a KBS-3 repository at Olkiluoto

The Olkiluoto site, located on the coast of south-western Finland (Figure 1-2), has been investigated for over 20 years. During the past few years, key activities in the pro-gramme have been related to:

completion of the investigations for site confirmation at Olkiluoto both through analyses of data from surface-drilled characterisation holes and surveys and studies carried out in the ONKALO underground research facility,

the design of required surface and disposal facilities, the development of the selected disposal technology to the level required for the

construction licence application, and demonstration of the long-term safety of the disposal of spent nuclear fuel including

the preparation of a safety case (Section 1.6) presented as a portfolio of reports, including the present report.

Posiva’s ongoing RTD (research, development and technical design) phase has been introduced in the TKS-2009 report (Posiva 2009) for the years 2010−2012, which also provides insight into developments from previous RTD phases. In 2012 a new RTD programme (YJH-2012) for 2013−2015 was published (Posiva 2013). In Figure 1-3, a general timeline of Posiva’s programme is presented.

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Figure 1-2. Olkiluoto Island is situated on the coast of the Baltic Sea in south-western Finland. Photograph by Helifoto Oy.

Figure 1-3. Overall schedule for nuclear waste management relating to the Loviisa and Olkiluoto reactors until 2020. The target is to begin disposal of spent nuclear fuel around 2020.

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The repository will be located in the bedrock of Olkiluoto Island taking into account the host rock properties as well as the restrictions set by urban planning in the Eurajoki Municipality. In Figure 1-4 the current reference layout is presented.

Figure 1-4. The current reference layout (green). Dark grey areas are not suitable for deposition tunnels based on Rock Suitability Classification (RSC), which has been de-veloped by Posiva. Red ovals denote respect distances to drillholes. The red line sur-rounding the repository shows the area reserved for the repository in urban planning.

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1.4 Regulatory context for the management of spent nuclear fuel

According to the law, the Finnish Ministry of Employment and the Economy (TEM; previously the Ministry of Trade and Industry, KTM) decides on the principles to be followed in waste management of spent fuel and other nuclear waste.

The schedule for the disposal of spent nuclear fuel was established in the KTM’s Deci-sion 9/815/2003. According to this Decision, the parties under the nuclear waste man-agement obligation shall, either separately, together or through Posiva Oy, prepare to present all reports and plans required to obtain a construction licence for a disposal fa-cility for spent nuclear fuel as stated in the Nuclear Energy Decree by the end of 2012. The disposal facility is expected to become operational around the year 2020.

The legislation concerning nuclear energy was updated in 2008. As part of the legisla-tive reform, a number of the relevant Government Decisions were replaced with Gov-ernment Decrees. The Decrees entered into force on 1st December 2008. The Govern-ment Decision (478/1999) regarding the safety of disposal of spent nuclear fuel, which particularly applied to the disposal facility, was replaced with Government Decree 736/2008, issued 27 November 2008.

Currently, the valid Regulatory Guides pertaining to nuclear waste management are Guides YVL D.1−D.5 issued by the Radiation and Nuclear Safety Authority (STUK) in 2013. Guide YVL D.1 deals with nuclear non-proliferation control, D.2 with the trans-port of nuclear material and nuclear waste, D.3 with the processing, storage and encap-sulation of spent nuclear fuel, D.4 with nuclear waste management and decommission-ing activities and D.5 with the disposal of nuclear waste. As these Guides were pub-lished in late 2013, the version of YVL D.5 used in the preparation of the TURVA-2012 safety case (see Section 1.6) was Draft 4 (17.3.2011, in Finnish only).

1.5 Safety concept and safety functions

The long-term safety principles of Posiva’s planned repository system are described at Level 2 of the VAHA (VAHA is Posiva’s requirement management system) as follows:

1. The spent nuclear fuel elements are disposed of in a repository located deep in the Olkiluoto bedrock. The release of radionuclides is prevented with a multi-barrier disposal system consisting of a system of engineered barriers (EBS) and host rock such that the system effectively isolates the radionuclides from the living environ-ment.

2. The engineered barrier system consists of a) canisters to contain the radionuclides for as long as they could cause significant harm to the environment, b) buffer between the canisters and the host rock to protect the canisters as long as containment of radionuclides is needed, c) deposition tunnel backfill and plugs to keep the buffer in place and help restore the natural conditions in the host rock, d) the closure, i.e. the backfill and sealing structures to decouple the repository from the surface environment.

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3. The host rock and depth of the repository are selected in such a way as to make it possible for the EBS to fulfil the functions of containment and isolation described above.

4. Should any of the canisters start to leak, the repository system as a whole will hinder or retard releases of radionuclides to the biosphere to the level required by the long-term safety criteria.

The safety concept, as depicted in Figure 1-5, is a conceptual description of how these principles are applied together to achieve safe disposal of spent nuclear fuel in the con-ditions of the Olkiluoto site. Due to the long-term hazard of the spent nuclear fuel, it has to be isolated from the surface environment over a long period of time. The KBS-3 method provides long-term isolation and containment of spent nuclear fuel by a sys-tem of multiple barriers, both engineered and natural, and by ensuring a sufficient depth of disposal (the key safety features of the system in Figure 1-5). All of these barriers have their roles in establishing the required long-term safety of the repository system. These roles constitute the safety functions of the barriers (see Table 1-1). The surface environment is not given any safety functions; instead it is considered as the object of the protection provided by the repository system. Most radionuclides in the spent nuclear fuel are embedded in a ceramic matrix (UO2) that itself is resistant to dissolution in the expected repository conditions. The slow re-lease of radionuclides from the spent nuclear fuel matrix is part of Posiva’s safety con-cept. Moreover, the near-field conditions should contribute to maintain the low solubil-ity of the matrix.

Figure 1-5. Outline of the safety concept for a KBS-3 type repository for spent nuclear fuel in a crystalline bedrock (adapted from Posiva 2003). Orange pillars and blocks indicate the primary safety features and properties of the disposal system. Green pillars and blocks indicate the secondary safety features that may become important in the event of a radionuclide release from a canister.

Retention and retardation of radionuclides

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SAFE DISPOSAL

LONG-TERM ISOLATION AND CONTAINMENT

FAVOURABLE, PREDICTABLE BEDROCK AND GROUNDWATER CONDITIONS

WELL-CHARACTERISED MATERIAL PROPERTIES

ROBUST SYSTEM DESIGN

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Implementation of the KBS-3 method entails the introduction of a number of additional barriers because of engineering, operational safety or long-term safety needs. Long-term safety needs arise, for example, because implementation involves the construction of a system of underground openings, including access tunnels and shafts, that would sig-nificantly perturb the safety functions of the host rock unless backfilled and sealed at closure of the disposal facility. These closure components with long-term safety func-tions include: backfill of underground openings, including the central tunnels, access tunnels,

shafts, and other excavations, and drillhole plugs, mechanical plugs, long-term hydraulic plugs at different depths and

plugs near the surface. The safety functions of the engineered barrier system (EBS) components and host rock are summarised in Table 1-1. In the TURVA-2012 safety case documentation, the spent nuclear fuel, EBS and the host rock are jointly termed the repository system, whereas the term disposal system is used when the repository system and the surface environ-ment are both considered (see Figure 1-6).

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Table 1-1. Summary of safety functions assigned to the barriers (EBS components and host rock) in Posiva’s KBS-3V repository.

Barrier Safety functions

Canister Ensure a prolonged period of containment of the spent nuclear fuel. This safety function rests first and foremost on the mechanical strength of the canister’s cast iron insert and the corrosion resistance of the copper sur-rounding it.

Buffer Contribute to mechanical, geochemical and hydrogeological conditions that are predictable and favourable to the canister,

Protect canisters from external processes that could compromise the safety function of complete containment of the spent nuclear fuel and associated radionuclides,

Limit and retard radionuclide releases in the event of canister failure.

Deposition tunnel backfill

Contribute to favourable and predictable mechanical, geochemical and hydrogeological conditions for the buffer and canisters,

Limit and retard radionuclide releases in the possible event of canister failure,

Contribute to the mechanical stability of the rock adjacent to the deposition tunnels.

Host rock Isolate the spent nuclear fuel repository from the surface environment and normal habitats for humans, plants and animals and limit the possibility of human intrusion, and isolate the repository from changing conditions at the ground surface,

Provide favourable and predictable mechanical, geochemical and hydro-geological conditions for the engineered barriers,

Limit the transport and retard the migration of harmful substances that could be released from the repository.

Closure Prevent the underground openings from compromising the long-term isola-tion of the repository from the surface environment and normal habitats for humans, plants and animals.

Contribute to favourable and predictable geochemical and hydrogeological conditions for the other engineered barriers by preventing the formation of significant water conductive flow paths through the openings,

Limit and retard inflow of water to and release of harmful substances from the repository.

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Figure 1-6. The components of the disposal system.

1.6 TURVA-2012 Safety Case portfolio

A safety case for a geological disposal facility documents the scientific and technical understanding of the disposal system, including the safety barriers and safety functions that these are expected to provide, results of a quantitative safety assessment, the proc-ess of systematically analysing the ability of the repository system to maintain its safety functions and to meet long-term safety requirements, and provides a compilation of evi-dence and arguments that complement and support the reliability of the results of the quantitative analyses.

As stated in Guide YVL D.5, A01: Compliance with the requirements concerning long-term radiation safety, and the suitability of the disposal method and disposal site, shall be proven through a safety case that must analyze both expected evolution scenarios and unlikely events impairing long-term safety. The safety case comprises a numerical analysis based on experimental studies and complementary considerations insofar as quantitative analyses are not feasible or involve considerable uncertainties (Govern-ment Decree GD 736/2008).

The TURVA-2012 safety case portfolio is based on the safety case plan published in 2008 (Posiva 2008), which updates an earlier plan published in 2005 (Vieno & Ikonen 2005). In the updated safety case plan, further details are provided on quality assurance and control procedures and their documentation, as well as on the consistent handling of different types of uncertainties. Since 2008, the safety case plan has been iterated based on the feedback received from the authorities, and the contents of the safety case portfo-lio TURVA-2012 are now as presented in Figure 1-7. In this report, all TURVA-2012 portfolio reports are referenced using the report title in italics. The full titles and report numbers are listed at the beginning of the reference list.

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Main reports

Main supporting documents

Site Description Biosphere DescriptionUnderstanding of the present state and past

evolution of the host rock

Understanding of the present state and evolution of the surface environment

Models and Data for the Repository System

Biosphere Data Basis

Description of climate evolution and definition of release scenarios

Models and data used in the performance assessment and in the analysis of the

radionuclide release scenarios

TURVA-2012

SynthesisDescription of the overall methodology of analysis, bringing together all the lines of arguments for safety, and the

statement of confidence and the evaluation of compliance with long-term safety constraints

Design Basis Performance targets and target properties for the repository system

Production LinesDesign, production and initial state of the EBS and the underground openings

Description of the Disposal System

Analysis of releases and calculation of doses and activity fluxes.

Complementary ConsiderationsSupporting evidence incl. natural and anthropogenic analogues

Data used in the biosphere assessment and summary of models

Biosphere Assessment: Modelling reports

Description of the models and detailed modelling of surface environment

Assessment of Radionuclide Release Scenarios for the

Repository SystemBiosphere Assessment

Summary of the initial state of the repository system and present state of the surface environment

Features, Events and ProcessesGeneral description of features, events and processes affecting the disposal system

Performance AssessmentAnalysis of the performance of the repository system and evaluation of the fulfillment of performance

targets and target properties

Formulation of Radionuclide Release Scenarios

Figure 1-7. TURVA-2012 safety case portfolio including report names (coloured boxes) and brief descriptions of the contents (white boxes). Disposal system = repository sys-tem + surface environment.

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The main reports and supporting documents of the TURVA-2012 portfolio have been described in the introduction to other main reports and will not be repeated here.

This FEPs screening and processing report is not in the portfolio. The FEP screening and processing methodology, although applied in TURVA-2012, has not been formally reported until now, though an auditing of the FEPs taken into account in previous safety assessment was reported by Vieno & Nordman (1997) and discussions on what FEPs should be taken into account in a safety case took place during the compilation of Rasi-lainen (2004) and of Miller & Marcos (2007). This report presents also an audit against the NEA Version 2.1 Project Databases. The reasoning on why the FEPs are screened out of the final list is also presented.

In the review of the pre-licensing documentation, STUK emphasises the need for aggre-gating/disaggregating FEPs, and this has been taken thoroughly into account.

1.7 Quality assurance

The quality assurance (QA) procedures for the safety case (SAFCA) portfolio (see Fig-ure 1-7) have been carried out following Posiva’s quality management system, which complies with the ISO 9001:2008 standard and considers relevant regulatory require-ments. Even though the quality assurance is based throughout on management accord-ing to the standard ISO 9001:2008, a graded approach proposed for nuclear facilities is adopted, i.e. the primary emphasis is on the quality control of the safety case, particu-larly for those activities that have a direct bearing on long-term safety, whereas standard quality measures are applied in the supporting work. This means, in practice, that the main safety case reports are subjected to stricter quality demands than general research activities. The input from Posiva’s own RTD activities and other research also fulfil the ISO 9001 quality standards.

The general quality guidelines of Posiva are also applied; the composition and quality management of portfolio reports and the recruitment of expert reviewers are carried out according to the respective guidelines. In addition, special attention is paid to the man-agement of the processes that are applied to produce the safety case and its foundations, which is the basis for the whole safety case process and organisation of the work. The purpose of this enhanced process control is to provide full traceability and transparency of the data, assumptions, models, calculations and results. The safety case production process is a part of Posiva’s RTD process and is linked to Posiva’s Production lines, Facility design and other main processes. The main customer is the Strategy process and the Licensing sub-process. The aim of the safety case production process is to produce the long-term safety documentation for the construction licence application. The safety case production process is owned by the research manager of Posiva’s Long-term Safety Unit in Posiva’s Research Department.

The overall plan, main goals and constraints for the safety case production process are presented in the Safety case plan (Posiva 2008). The details of how the Safety case plan 2008 is being implemented are described in the SAFCA project plan. The work is man-aged and coordinated by a SAFCA core group and supervised by a steering group.

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The safety case production process is divided into four main sub-processes: Conceptu-alisation and Methodology, Data Handling and Modelling, Safety Assessment, and Evaluation of Compliance and Confidence.

The Data Handling and Modelling sub-process constitutes the central linkage between Posiva’s main technical and scientific activities and the production of the safety case. It is a clearinghouse activity between the supply of, and demand for, quality-assured data for the safety case. Data are produced by Posiva’s planning, design and development processes for the EBS (Engineered Barrier System), by the site characterisation process for the geoscientific data and through the biosphere description of the Olkiluoto area.

A SAFCA quality co-ordinator (QC) has been designated for the activities related to the quality assurance measures applied to the production of the safety case contents. The QC is responsible for checking that the instructions and guidelines are followed, and improvements are made in the process as deemed useful or necessary. The QC is also responsible for the coordination of the external expert reviews, maintenance of sched-ules, review and approval of the products, and the management of the expert elicitation process. The QC also leads the quality review of models and data used in the Data Han-dling and Modelling sub-process. Regular auditing of the safety case production process is done as part of Posiva's internal audit programme.

Data sources and quality aspects of the sources are documented according to a specific guideline. Individual data and databases are approved through a clearance procedure supervised by the SAFCA Quality Co-ordinator. The process owner checks and ap-proves the data and the QC checks and approves the procedure. Data used may also be approved using other Posiva databases such as VAHA or POTTI and the respective ap-proval processes. A clearance procedure has been applied to all key data used in the performance assessment (i.e. showing compliance with performance targets and target properties), and in the safety assessment (i.e. radionuclide transport and dose calcula-tions).

The control and supervision of the safety case products (i.e. main portfolio reports) has been done in two steps, first an internal review by safety case experts and subject-matter experts within Posiva’s RTD programme and then the second step by external expert reviewers. A group of external experts covering the essential areas of knowledge and expertise needed in the safety case production has been set up. The review process is based on review templates, which record each review comment and how it has been addressed. Upon completion, this template is checked and approved according to the quality guidelines of Posiva.

An expert elicitation process has been applied to specific cases when the understanding or data basis is conflicting and consensus is needed for the selection of key data (e.g. future climate scenarios, solubility and sorption data). This expert elicitation process has been initiated, recruited, documented and managed by the SAFCA Quality Co-ordinator.

QA issues are discussed further in the Synthesis. Quality assurance and quality control measures related to the production and operation of the repository are discussed in detail

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in the Production Line reports (Canister, Buffer, Backfill, Closure and Underground Openings).

1.8 Scope and objectives of the present report

This report documents the screening and processing of features, events and processes (FEPs) starting from NEA Version 2.1 Project Databases that has been carried out within TURVA-2012. The main objective is the FEP screening process that has been used to show that Posiva’s FEP list, as described in Features, Events and Processes, is adequate for the current stage of the spent nuclear fuel management programme. The disposal system, as defined in Figure 1-6 includes the spent nuclear fuel, the engineered barriers surrounding it, the host rock, and the surface environment. The disposal system will evolve over time. The evolution of the disposal system will depend on:

- the initial state of the system (relevant features are summarised in Description of the Disposal System),

- a number of processes acting within the disposal system, and

- external influences (events and processes) acting on the system.

The focus of the present report is on the FEPs related to the repository system and ex-ternal FEPs. The processing for the FEPs related to the surface environment is here lim-ited to the initial step, the relevance screening (Chapter 3). This is due, on the one hand, to the lack of resources and, on the other hand, to the emphasis given by the Finnish regulator STUK, to the FEPs related to the repository system.

1.9 Structure

The structure of the present report is as summarised below.

Chapter 2 presents the overall FEP screening and processing methodology.

Chapter 3 presents the outcome of the relevance and significance screening steps performed on the NEA Version 2.1 Project Databases.

Chapter 4 presents the further processing of the screened in FEPs and the mapping of the TURVA-2012 FEP list to the screened in FEPs.

In Chapter 5 a cross-checking of the TURVA-2012 FEP list is performed against FEP lists developed in other relevant projects and FEPs in Posiva’s 2007 Process Report (Miller & Marcos 2007).

Chapter 6 concludes on the advantages and challenges of the TURVA-2012 FEPs classification and provides a discussion on comprehensiveness.

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2 METHODOLOGY FOR FEP SCREENING AND PROCESSING

2.1 Overall methodology

A central feature of Posiva’s TURVA-2012 safety case is the formulation and analysis of a set of scenarios that, collectively, represent the envelope of future evolutions for a KBS-3V type disposal facility at the Olkiluoto site. The definition and formulation of scenarios is supported by the identification and consideration of all potentially relevant features, events and processes (FEPs) that, on the one hand, characterise the system, and on the other hand might occur during system evolution, and that have the potential to affect long-term safety. These FEPs are discussed in detail in Features, Events and Processes. Focusing on FEPs when developing the scenarios is in line with international recommendations regarding the development, operation and closure of disposal facili-ties and international best practice applied. For example, the Specific Safety Require-ments on Disposal of Radioactive Waste (IAEA 2011) states in Requirement 15 on Site characterization for a disposal facility that:

The site for a disposal facility shall be characterized at a level of detail sufficient to support a general understanding of both the characteristics of the site and how the site will evolve over time. This shall include its present condition, its probable natural evolution and possible natural events, and also human plans and actions in the vicinity that may affect the safety of the facility over the period of interest. It shall also include a specific understanding of the impact on safety of features, events and processes associated with the site and the facility.

More specifically, the Specific Safety Guide on The Safety Case and Safety Assessment for the Disposal of Radioactive Waste (IAEA 2012) states (5.42):

Regardless of the method used for developing the scenarios, all features, events and processes that could significantly influence the performance of the disposal system should be addressed in the assessment.

Posiva’s methodology for scenario formulation, related to the repository system, follows a ‘top-down’ approach in first identifying the safety functions that are required of the repository system, then considering the effects of single FEPs or combinations of FEPs on those functions to check that the scenarios are comprehensive (Formulation of Ra-dionuclide Release Scenarios, Section 2.5). However, Posiva’s methodology for the FEP screening component in the overall FEP processing is more closely related to the ‘bottom-up’ approach for scenario development described, for example, in the ISAM project (IAEA 2004). When using this method, a comprehensive list of features, events and processes is developed as a starting point. This may involve the use of generic lists of features, events and processes (internationally agreed lists, regulations, etc.) and the determining of site- and system-specific features, events and processes (as discussed above). This is followed by a screening process to exclude features, events and proc-esses from further considerations that are either irrelevant for the KBS-3 concept or considered to have insignificant impact on the long-term safety of the disposal system. Criteria for screening features, events and processes may include rules relating to regu-lations and/or to the probability of occurrence or consequences of events and processes. The sections below describe the step-wise FEP screening method, and further process-

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ing, applied in demonstrating that the TURVA-2012 FEP list for the repository system and external events and processes is comprehensive enough.

2.2 FEP screening and processing steps

Features, events and processes that might occur, and that have the potential to affect long-term safety under certain conditions are accounted for in the safety assessment in the TURVA-2012 safety case. These FEPs are presented and discussed in Features, Events and Processes. This section describes the identification and screening of FEPs and their further processing and cross-checking that was conducted in order to assess the comprehensiveness of the TURVA-2012 FEP list. The work has been conducted in a structured step-wise manner mainly relying on expert judgement. Each step in the proc-ess is elaborated in the sub-sections below and they are summarised as follows:

1. Selecting an initial comprehensive FEP list to use as a starting point.

2. Performing a relevance screening based on a set of screening criteria aiming at screening out FEPs not relevant for the KBS-3 concept or the TURVA-2012 safety case.

3. Performing an initial aggregation of FEPs with an identical heading or meaning, and the classification of the FEPs under the components of the disposal system (or as ex-ternal if they are external to the system).

4. Performing a significance screening based on a set of screening criteria aiming at screening out FEPs clearly insignificant for long-term safety.

5. Mapping the FEPs not screened out in previous steps to the TURVA-2012 FEP list. This step contains, for example, the aggregation and disaggregation of FEPs to fol-low Posiva’s FEP nomenclature.

6. Cross-check the final TURVA-2012 FEP list against FEP lists developed in other relevant projects.

2.3 Identification and screening of FEPs for potential significance

2.3.1 The initial FEP list

The FEP screening is based on the FEP list from NEA 2.1 Project Databases (NEA 2006), which was the latest NEA FEP database available in 2011 when the FEPs in Features, Events and Processes were compiled.

2.3.2 Relevance screening

A relevance screening, aiming to screen out FEPs not relevant for a KBS-3V type re-pository or the TURVA-2012 safety case, is performed on the FEPs in the NEA Version 2.1 Project Databases, below denoted as Project FEPs. A set of criteria has been set out to facilitate this screening. A Project FEP is screened out if at least one of the five fol-lowing screening criteria is fulfilled:

R1 The Project FEP is defined by a heading without any description of what is meant by the heading.

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R2 The Project FEP is related to assessment methodology. These FEPs are handled elsewhere in the TURVA-2012 safety case.

R3 The Project FEP is not relevant for the context of the TURVA-2012 safety case, especially in respect to the national regulatory requirements and guide-lines.

R4 The Project FEP is not relevant for the KBS-3V type repository design for spent nuclear fuel disposal.

R5 The Project FEP is not relevant for the present-day Olkiluoto site characteris-tics and likely future site characteristics evolving in response to climatic changes and other external factors.

2.3.3 Initial aggregation and component-wise classification of the FEPs

The second step in the process includes:

the initial aggregation of the Project FEPs screened in that have identical heading or meaning. At this stage, the individual project-specific FEP descriptions are, how-ever, kept in the documentation for the benefit of the experts carrying out the next screening step (Section 2.3.4).

the classification of the aggregated FEPs under the component(s) of the disposal system, i.e. spent fuel, canister, buffer, backfill, auxiliary components, geosphere or surface environment or they are classified as “external” if they are related to condi-tions external to the disposal system. A FEP is classified under several components if it is not obvious that it only relates to one component (e.g. “soil moisture and evaporation” is only mapped to surface environment, whereas “diffusion” is classi-fied to all components of the disposal system).

2.3.4 Significance screening

The third step in the process is to conduct a screening evaluation of the Project FEPs not screened out in the relevance screening, aiming at screening out FEPs clearly insignifi-cant for long-term safety. A set of criteria regarding a FEP’s impact on safety functions and radiation protection criteria (these are doses and activity fluxes; there are FEPs af-fecting e.g. exposure pathways that have an impact on the end points regarding radiation protection criteria, but these FEPs have no impact on safety functions) has been defined to facilitate this screening. A Project FEP is screened out if at least one of the following significance screening criteria is fulfilled:

S1 The FEP has insignificant impact on safety functions and radiation protection criteria.

S2 The FEP has low probability to occur and low impact on safety functions and radiation protection criteria.

S3 The FEP itself has considerably more serious consequences than any potential radiological consequences from the spent nuclear fuel.

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2.4 Mapping remaining Project FEPs to the TURVA-2012 FEP list

The outcome of the steps in the FEP screening and initial processing described above is a list of NEA Project FEPs potentially safety relevant for a KBS-3V repository at the Olkiluoto site. These FEPs have been aggregated and classified under relevant compo-nents of the disposal system or as external FEPs. This list is mapped to TURVA-2012 FEPs to check that they include all FEPs relevant for the KBS-3V system at Olkiluoto. The full TURVA-2012 FEP list is presented in Appendix A. An explanation is given, when necessary, in case a remaining NEA Project FEP has not a clear corresponding TURVA-2012 FEP.

2.5 Cross-checking

The final step is to cross-check the TURVA-2012 FEP list against relevant sources to increase the confidence in that no important FEPs have been omitted. Of importance is to cross-check against FEP lists developed in other relevant projects, especially the lists underpinning safety assessments performed by SKB for a KBS-3V type repository for spent nuclear fuel disposal. A cross-check against the FEP list in Miller & Marcos (2007) is also included.

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3 SCREENING AND PROCESSING OF THE FEPS

3.1 FEP lists included in the work

The screening process was based on the NEA FEP list (NEA Version 2.1 Project Data-base), which is a compilation of FEPs included in several spent nuclear fuel disposal programmes around the world (i.e. Goodwin et al. 1994, NAGRA 1994, DOE 1996, Chapman et al. 1995, Miller et al. 2002, Miller & Chapman 1993, Bronders et al. 1994). Other FEP lists or sources of information used are discussed in Chapter 5 where the final list is cross-checked against relevant literature. Cross-checking includes data from SKB’s SR-Site (SKB 2010a) (Section 5.1), NWMO’s Fourth Case Study (Garisto 2012) (Section 5.2) and comparison to earlier work done by Posiva (Section 5.3).

3.2 Relevance screening results

Relevance screening was performed following the protocol presented in Section 2.3.2. The number of Project FEPs in version 2.1 of the NEA FEP database is large, in total there are 1671 FEPs (Electronic Appendix 1, NEA version 2.1 Project Database). In order to make the relevance screening more efficient, a workshop exercise was carried out by a group of safety assessment experts.

This screening process is documented in Electronic Appendix 1 (NEA version 2.1 Pro-ject Databases – Relevance screening_final), where screening decisions based on R-criteria (see Section 2.3.2) are listed. The final table shows the result of the initial work-shop as well as including additional screening decisions that were revised during further steps, i.e. cross-check, of the work.

The relevance screening resulted in 1154 FEPs being screened in and 517 FEPs being screened out; the latter were divided among the individual screening criteria:

R1: 119 FEPs screened out




R5: 110 FEPs screened out.

3.3 Preliminary aggregation of FEPs and classification under disposal system components

A preliminary aggregation of the FEPs and their classification under components of the disposal system (or as external to the system) was done before moving to the Signifi-cance screening phase. The protocol for the process is described in Section 2.3.3. The aggregation was done to collate FEPs that were duplicates in the NEA FEP list in order to simplify the following steps. FEPs were then classified under the following compo-nents (reflecting those discussed in Features, Events and Processes):

spent fuel

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canister buffer backfill auxiliary components geosphere surface environment external FEPs.

The aggregation was documented in an Excel file which was used as a basis for the Sig-nificance screening. Hence the, aggregation is shown also in the documentation of the Significance screening results and is not duplicated here (see Section 3.4 and Electronic Appendix 2, NEA version 2.1 Project Databases – Significance screening and justifica-tions).

After the preliminary aggregation, the number of FEPs in the list was 735. It should be noted that some of these FEPs (168 in total) were exclusively related to the surface en-vironment, and these FEPs were not further processed.

3.4 Significance screening results

The Significance screening was performed in accordance to the protocol presented in Section 2.3.4. The significance screening requires a deeper process understanding com-pared with the relevance screening. Hence, the screening involved various subject mat-ter experts for the different components of the disposal system and external conditions. Initial screening was carried out by a group of experts in a significance screening work-shop, and the justifications for screening out FEPs were written later by individual ex-perts. The components included in the significance screening were all those listed above (Section 3.3), except for the surface environment.

The Significance screening was documented in an Excel file on top of the initial aggre-gation of the FEPs (Section 2.3.3). As noted above FEPs that relate only to the surface environment (168 FEPs in total) are shown in the Excel sheet but they were not further processed. Thus, 567 FEPs remained to be screened in this phase. The screening deci-sions based on the Significance criteria and justification for “OUT” screening decisions are presented in Electronic Appendix 2 (NEA version 2.1 Project Databases – Signifi-cance screening and justifications).

The significance screening resulted in 491 FEPs being screened in and 76 FEPs being screened out. The latter were divided among the individual screening criteria:

S1: 55 FEPs screened out

S2: 16 FEPs screened out

S3: 5 FEPs screened out.

See Electronic Appendix 2 for justifications why these FEPs were screened out in this phase (column “Justification”).

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4 MAPPING REMAINING PROJECT FEPS TO THE TURVA-2012 FEP LIST

After the screening phase (Chapter 3), the resulting FEP list (comprising 491 screened-in FEPs) was divided to component-wise lists, which were then used in the mapping against Posiva’s FEPs to show that the TURVA-2012 FEP list is comprehensive enough. The full TURVA-2012 FEP list is given in Appendix A.

Initial mapping was done by the project group for each component included in this phase (spent fuel, canister, buffer, backfill, auxiliary components, geosphere and exter-nal). The results were cross-checked within the project group. Mapping of the FEPs is documented in Appendix B (Tables B-1 to B-7). In the mapping, FEP names from the TURVA-2012 (Features, Events and Processes) were used. Project FEPs not included in the TURVA-2012 FEP list were marked as “NA” (Not Applicable) in the mapping tables with a note (justification or explanation).

The number of Project FEPs not applicable (NA) to the components was 21 for the FUEL (FU), 24 for the CANISTER (CA), 11 for the BUFFER (BU), 15 for the BACK-FILL (BA), 12 for the AUXILIARY COMPONENTS (A), 5 for the GEOSPHERE (G) and 2 for EXTERNAL (E). The main reasons were that the Project FEP did not occur in the component itself, being in most cases treated in interaction matrices (e.g. Table 3-4, p. 54 in Features, Events and Processes). In other cases the Project FEP was not found as a TURVA-2012 FEP, but its consequences were treated under other relevant FEPs of TURVA-2012, belonging to the same component or to others.

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5 CROSS-CHECKING AGAINST OTHER RELEVANT FEP SOURCES

In this chapter, the TURVA-2012 FEP list is compared with other relevant FEP lists produced after the compilation of NEA’s Project Databases Version 2.1 but before the publication of Features, Events and Processes in 2012. The FEP lists considered here include those related to the following safety assessments for deep geological reposito-ries in crystalline environments:

Sweden’s SR-Site (SKB 2010a),

Canada’s Fourth Case Study (Garisto 2012).

The purpose of this section is to cross-check whether all FEPs from these safety assess-ments are also included in the TURVA-2012 FEP list, and if not, the reasons for their omission are explored. The cross-checking is done by going through the entire FEP list in question and by mapping the FEPs to one or (if necessary) several FEPs of the TURVA-2012 FEP list (Tables C-1 and D-1 in Appendices C and D). If a FEP cannot be mapped to any TURVA-2012 FEP, the reason for the omission is documented. Fur-thermore, all TURVA-2012 process FEPs (excluding the surface environment FEPs) are mapped to process FEPs in the above-mentioned assessments (Tables C-2 and D-2 in Appendices C and D).

5.1 Cross-checking against the Swedish SR-Site

The SR-Site FEP catalogue (SKB 2010a) has been mapped to TURVA-2012 FEPs in Appendix C to check the comprehensiveness of the TURVA-2012 FEP list. All SR-Site FEPs that could not be mapped directly to any TURVA-2012 FEP are shown in Table 5-1. It came out that the FEP lists are fairly similar with the few exceptions mentioned in Table 5-1. Differences are mainly due to the fact that assessment methodology issues (including quality control issues) are not treated as FEPs in TURVA-2012 but are han-dled elsewhere in the safety case and/or in other documents presented for the construc-tion licence application (CLA). Also, a few irrelevant FEPs (e.g. earth currents, lique-faction of bentonite) have been excluded from Posiva’s FEP list already before TURVA-2012, but they are included in the SR-Site FEP catalogue, even if concluded to be irrelevant in the assessment.

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Table 5-1. SR-Site FEPs (SKB 2010a, Tables 5-1...5-12, Sections 5.6, 5.7 and 5.8 and Appendix 2) that were not found in the TURVA-2012 FEP list (see Table C-1). FEPs that were excluded from the SR-Site assessment (shown in grey in Table C-1) are not included here, nor any surface environment FEPs.

FEP number in SR-Site

FEP name in SR-Site Note

ISGen02 Effects of phased op-eration

Operation schedule is handled elsewhere in TURVA-2012 (e.g. waste emplacement schedule used in thermal dimensioning).

ISGen03 Incomplete closure Out of the scope of the post-closure safety case TURVA-2012 that assumes the disposal facility to be properly closed.

ISC01 Mishaps – canister Canister handling accidents discussed in Performance Assess-ment but not included as a FEP, as any canister damaged during operation is assumed to be replaced. Operational safety is outside the scope of TURVA-2012.

ISC02 Design deviations – canister

Initial penetrating defect(s) assumed in several radionuclide re-lease scenarios.

ISBu01 Mishaps – buffer Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to buffer production and emplacement. QC issues are related to assessment methodology and are handled elsewhere in TURVA-2012.

ISBu02 Design deviations – buffer

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to buffer production and emplacement. QC issues are related to assessment methodology and are handled elsewhere in TURVA-2012.

ISBfT01 Mishaps – backfill in tunnels

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to backfill production and emplacement. QC issues are related to assessment methodology and are handled elsewhere in TURVA-2012.

ISBfT02 Design deviations – backfill in tunnels

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to backfill production and emplacement. QC issues are related to assessment methodology and are handled elsewhere in TURVA-2012.

ISBP01 Mishaps – bottom plate in deposition holes

The bottom plate is not a component in Posiva’s current repository design.

ISBP02 Design deviations – bottom plate in deposi-tion holes

The bottom plate is not a component in Posiva’s current repository design.

ISPg01 Mishaps – plugs Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to the production and emplacement of closure plugs (auxiliary components). QC issues are related to assessment methodology and are handled else-where in TURVA-2012.

ISPg02 Design deviations – plugs

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to the production and emplacement of closure plugs (auxiliary components). QC issues are related to assessment methodology and are handled else-where in TURVA-2012.

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ISCA01 Mishaps – central area Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to the selection, produc-tion and emplacement of closure materials and structures. QC issues are related to assessment methodology and are handled elsewhere in TURVA-2012.

ISCA02 Design deviations – central area

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to the emplacement of closure materials and structures. QC issues are related to as-sessment methodology and are handled elsewhere in TURVA-2012.

ISTS01 Mishaps/Design devia-tions – top seal

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to the emplacement of closure materials and structures. QC issues are related to as-sessment methodology and are handled elsewhere in TURVA-2012.

ISBhS01 Mishaps/Design devia-tions – borehole seals

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are successfully applied to the emplacement of borehole seals. QC issues are related to assessment methodology and are handled elsewhere in TURVA-2012.

F06 Mechanical cladding failure

Not a FEP in itself in TURVA-2012, but the potential consequence of other FEPs, such as e.g. 3.2.7, 4.2.3.

C13 Earth currents – stray current corrosion

Excluded already in Posiva’s previous Process Report (Miller & Marcos 2007) because the FEP had insignificant consequences as reported in SR-Can.

Bu09 Liquefaction Not relevant. Disregarded also in SR-Site since liquefaction from a short pulse cannot occur in a high density bentonite, due to high effective stresses (SKB 2010b, Table 2-4).

BfT08 Liquefaction Not relevant. Disregarded also in SR-Site as not relevant (SKB 2010b, Table 2-9).

BfT17 Radiation-induced transformations

Not a relevant FEP for backfill. Radiation effects on backfill proper-ties were disregarded also in SR-Site (SKB 2010a, p. 132).

Ge05 Displacements in intact rock

Not a specific FEP, but taken into account in the modelled rock properties.

Ge09 Surface weathering and erosion

Erosion is discussed in Complementary Considerations in Section 7.5. Surface weathering effects are considered in the geological model of the Olkiluoto site.

In SR-Site this FEP has been moved under Climate and Bio-sphere (SKB 2010a, Section 4.1.5).

Ge22 Radiation effects (rock and grout)

Radiation effects are not significant in the geosphere. They were disregarded also in SR-Site because of too low radiation fluxes (SKB 2010c, Table 1-4).

Ge23 Earth currents Not relevant. Disregarded also in SR-Site since expected electrical potential fields are too small to affect groundwater flow or solute transport (SKB 2010c, Table 1-4).

Pg08, CA08, TS08, BhS08

Liquefaction Not relevant. Disregarded also in SR-Site, since impact is low (in central area backfill) or cannot occur at all (in other components) (SKB 2010b, Tables 2-14 and 2-16).

VarBu01 Radiation intensity Taken into account in 5.2.5, but not a feature of the buffer in itself.

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VarBu08 Stress state Taken into account in 5.2.2, but not a feature of the buffer in itself.

VarBfT07 Stress state Taken into account in 6.2.2, but not a feature of the backfill in itself.

VarPg07 Stress state Will vary according to water uptake and swelling in the clay com-ponents of the plugs.

VarCA07 Stress state Will vary according to water uptake and swelling in the clay com-ponents of the central areas.

Cli04 Climate system – Cli-mate in Sweden and Forsmark

Climate in Finland and at Olkiluoto is considered (10.2.1).

LSGe01 Mechanical evolution of the Shield

Not included as a specific FEP because the tectonic situation in the Olkiluoto area is very likely to be stable in the one million year assessment time frame (post-glacial earthquake effects consid-ered in FEP 8.2.3 and in the RS and RS-DIL scenarios).

FHA01 General considerations Not a FEP in itself, but relates to assessment methodology (pro-jected to the near future).

FHA02 Societal analysis, con-sidered societal as-pects

Not a FEP in itself, but relates to assessment methodology (pro-jected to the near future).

FHA03 Technical analysis, general aspects

Not a FEP in itself, but relates to assessment methodology (pro-jected to the near future).

SiteFact02 Construction of nearby rock facilities

Taken into account in the site selection process. Dealt with else-where in the construction licence application (CLA) – also in Olkiluoto Site Descriptive model (OSD).

SiteFact03 Nearby nuclear power plant

Taken into account in the site selection process. Dealt with else-where in the CLA.

SiteFact04 Mine excavation Taken into account in the site selection process. Dealt with else-where in the CLA – also OSD.

Meth01 Assessment basis Related to assessment methodology and thus handled elsewhere in TURVA-2012.

Meth02 Assessment methodol-ogy

Assessment methodology is handled elsewhere in TURVA-2012.

The mapping of TURVA-2012 process FEPs to SR-Site process FEPs (Table C-2 in Appendix C) revealed that all TURVA-2012 process FEPs can be directly mapped to SR-Site FEPs, indicating that the TURVA-2012 FEP list includes only processes that are considered relevant also in SR-Site.

5.2 Cross-checking against the Canadian Fourth Case Study

In Appendix D, NMWO’s (Nuclear Waste Management Organization) Fourth Case Study FEP list (Garisto 2012) has been mapped to TURVA-2012 FEPs. All Fourth Case Study FEPs that could not be mapped directly to any TURVA-2012 FEP are shown in Table 5-2. The omissions are mainly due to the fact that assessment methodology is handled elsewhere in TURVA-2012, not as specific FEPs. Also, some differences are due to different fuel type and repository concept. It should be noted that the Fourth Case

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Study was a generic (not site-specific) safety assessment and it was a less extensive as-sessment than the TURVA-2012 safety case. Many FEPs were screened out in Garisto (2012) although they were presented in the original FEP list. Such FEPs are shown in grey in Table D-1 (Appendix D).

Table 5-2. Fourth Case Study FEPs (Garisto 2012, Tables 2.1, 2.2, 2.3) that were not found in the TURVA-2012 FEP list (see Table D-1). FEPs that were screened out in Garisto (2012) and shown in grey in Table D-1 are not included here, nor any surface environment FEPs.

FEP num-ber in Garisto (2012)

FEP name in Garisto (2012) Note

0.0.01 Aims of the assessment Related to assessment methodology and handled elsewhere in TURVA-2012.

0.0.02 Regulatory requirements and exclu-sions

Related to assessment methodology and handled elsewhere in TURVA-2012.

0.0.03 Impacts of concern Related to assessment methodology and handled elsewhere in TURVA-2012.

0.0.04 Time scales of concern Related to assessment methodology and handled elsewhere in TURVA-2012.

0.0.05 Spatial domain of concern Related to assessment methodology and handled elsewhere in TURVA-2012.

0.0.06 Repository assumptions Related to assessment methodology and handled elsewhere in TURVA-2012.

1.1.03 Placement of wastes and backfill Related to the operational phase and handled else-where in TURVA-2012.

1.1.05 Repository records and markers Out of the scope of TURVA-2012.

1.1.06 Waste allocation Related to the layout of repository handled else-where in TURVA-2012.

1.1.07 Repository design Repository design is handled elsewhere in TURVA-2012 (e.g. layout designs used by groundwater flow modelling; waste emplacement schedule used in thermal dimensioning).

1.1.08 Quality control QC issues are related to assessment methodology and are handled elsewhere in TURVA-2012.

1.1.09 Schedule and planning Schedule issues are handled elsewhere in TURVA-2012 (e.g. waste emplacement schedule used in thermal dimensioning).

1.1.10 Repository administrative control Out of the scope of TURVA-2012.

1.1.11 Monitoring Handled elsewhere in TURVA-2012 (considered in repository design).

1.4.08 Social and institutional develop-ments

Out of the scope of TURVA-2012.

34

2.1.01.B Inventory of chemically toxic con-taminants

Chemotoxicity is out of scope of TURVA-2012.

2.1.02.A Characteristics of used CANDU fuel (UO2)

Not applicable (different fuel type). Spent fuel char-acteristics considered by all spent fuel FEPs.

2.1.03.A Repository layout Repository design is handled elsewhere in TURVA-2012 (e.g. layout designs used by groundwater flow modelling).

2.2.01 Excavation disturbed zone EDZ considered in groundwater flow modelling variants.

2.2.12 Undetected features (geosphere) Out of scope of TURVA-2012.

3.1.02 Chemical and organic toxin stability Chemotoxicity is out of the scope of TURVA-2012.

The mapping of TURVA-2012 process FEPs to the Canadian Fourth Case Study proc-ess FEPs (Table C-2 in Appendix C) revealed that there are several processes that are considered in TURVA-2012 but that were not specifically included as FEPs in the Ca-nadian assessment. This is mainly due to the generic nature of the Canadian assessment.

5.3 Comparison with FEPs in Process Report 2007-12

Most FEPs in Posiva’s Process Report 2007 (Miller & Marcos 2007) are exactly the same as the TURVA-2012 FEPs, the descriptions being updated in the latest. However, according to the feedback received from the Finnish regulator on the Process Report in 2007, a few repository system-related FEPs have been added and some other disaggre-gated as seen now in Table 5-3. The major change is the addition of the surface envi-ronment FEPs in the latest report, but these are not listed below. Other additions are the FEP criticality to the component “Spent nuclear fuel” and freezing and thawing to the buffer, backfill and auxiliary components.

35

Table 5-3. Main changes since the FEPs in Process Report 2007.

FEPs in Process Report 2007 Corresponding FEPs in TURVA-2012

FEP num-ber

FEP name FEP number

FEP name

3.2.2 Radiogenic heat generation and heat transfer

3.2.2 Heat generation

3.2.3 Heat transfer

3.2.5 Radiolysis of groundwater 3.2.5 Radiolysis of residual water (in an intact canister)

3.2.6 Radiolysis of the canister water

3.2.8 Dissolution of the gap inventory 3.2.9 Release of the labile fraction of the inventory

4.2.8 Corrosion of the copper overpack 4.2.5 Corrosion of the copper overpack

4.2.7 Stress corrosion cracking

5.2.2 Water uptake 5.2.2 Water uptake and swelling

5.2.4 Swelling/mass redistribution

5.2.3 Piping and erosion, including chemi-cal erosion

5.2.3 Piping and erosion

5.2.4 Chemical erosion

8.3.2 Groundwater flow (advection) 8.3.5 Groundwater flow and advective transport 8.3.3 Dispersion

37

6 CONCLUSIONS AND THE WAY FORWARD

Comprehensiveness/completeness of a FEP list cannot be proven with absolute cer-tainty. However, confidence in that the TURVA FEP list is as comprehensive as possi-ble at this stage of the Safety Case has been gained through a combination of systematic reviews (both top-down and bottom-up), audits, and comparisons with other FEP lists.

6.1 Comprehensiveness of TURVA-2012 FEP list

To show that the TURVA-2012 FEP list is comprehensive enough for the purpose of the CLA, it is necessary to demonstrate that the FEPs in the list cover the entire range of potentially relevant phenomena at a sufficient level of detail. This has been done in the TURVA-2012 reports: Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of Radionuclide Release Scenarios for the Repository System, Biosphere Assessment and Models and Data for the Repository System. In these reports the interactions and couplings between FEPs are dealt with. The uncertainty in the oc-currence and extent of the FEPs is taken into account in formulating and analysing the scenarios and in the selection of the models and data used in the assessment of the sce-narios.

Interaction between FEPs are not considered as individual FEPs, and thus, not reported as such in the TURVA-2012 FEP list. The cross-checking in Chapter 5 has not resulted in the identification of FEPs that should be considered in the future.

The regulator STUK recommended (STUK 2009) to take into account for the buffer component a FEP called “Drying under thermal gradient and potential shrinkage”. Be-ing the reverse of “Water uptake and swelling” and considering the thermal gradients in the repository (see Figure 6.5 in Models and Data for the Repository System), the con-sequences of the FEP as suggested are considered insignificant (see also paragraph 5 in Models and Data for the Repository System, page 292), and thus it does not appear in the TURVA-2012 FEP list. Nonetheless to avoid misunderstanding, it is acknowledged that it could be added in the future.

6.2 The way forward

The basis for the FEP processing in TURVA-2012 has mainly been the NEA Ver-sion 2.1 Project Databases (NEA 2006), the previous Posiva Process Report (Miller & Marcos 2007) and FEP lists developed in other relevant safety cases. For the next safety case, supporting the application for operating licence for Posiva’s spent nuclear fuel repository, the most apparent task is to account for new information. What new infor-mation will be available is not possible to foresee, but two sources that should be con-sidered in the FEP processing are the updated NEA FEP list expected to be released in 2014 and new knowledge gained from Posiva’s RTD programme.

Processing FEPs is a task that is beneficial to perform in a continuous manner through-out the development of a safety case, and during iterations of several safety cases in a radioactive waste programme. To facilitate this, tools for a systematic documentation of the process are needed. Posiva will further develop the current electronic FEP database to be able to handle the documentation of the entire FEP processing.

39

REFERENCES

TURVA-2012 Portfolio MAIN reports:

Assessment of Radionuclide Release Scenarios for the Repository System Safety case for the disposal of spent nuclear fuel at Olkiluoto - Assessment of Radionu-clide Release Scenarios for the Repository System 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-09. ISBN 978-951-652-190-2. Biosphere Assessment Safety case for the disposal of spent nuclear fuel at Olkiluoto - Biosphere Assessment BSA-2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-10. ISBN 978-951-652-191-9.

Biosphere Data Basis Safety case for the disposal of spent nuclear fuel at Olkiluoto - Data Basis for the Bio-sphere Assessment BSA-2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-28. ISBN 978-951-652-209-1.

Biosphere Radionuclide Transport and Dose Assessment Modelling Safety case for the disposal of spent nuclear fuel at Olkiluoto - Radionuclide Transport and Dose Assessment for Humans in the Biosphere Assessment BSA-2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-31. ISBN 978-951-652-212-1.

Complementary Considerations Safety case for the disposal of spent nuclear fuel at Olkiluoto - Complementary Consid-erations 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-11. ISBN 978-951-652-192-6.

Description of the Disposal System Safety case for the disposal of spent nuclear fuel at Olkiluoto - Description of the Dis-posal System 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-05. ISBN 978-951-652-186-5.

Design Basis Safety case for the disposal of spent nuclear fuel at Olkiluoto - Design Basis 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-03. ISBN 978-951-652-184-1.

Dose Assessment for Plants and Animals Safety case for the disposal of spent nuclear fuel at Olkiluoto - Dose Assessment for Plants and Animals in the Biosphere Assessment BSA-2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-32. ISBN 978-951-652-213-8.

Features, Events and Processes Safety case for the disposal of spent nuclear fuel at Olkiluoto - Features, Events and Processes 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-07. ISBN 978-951-652-188-9.

Models and Data for the Repository System Safety case for the disposal of spent nuclear fuel at Olkiluoto - Models and Data for the Repository System 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2013-01.

40

Performance Assessment Safety case for the disposal of spent nuclear fuel at Olkiluoto - Performance Assessment 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-04. ISBN 978-951-652-185-8.

Surface and Near-Surface Hydrological Modelling Safety case for the disposal of spent nuclear fuel at Olkiluoto - Surface and Near-surface Hydrological Modelling in the Biosphere Assessment BSA-2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-30. ISBN 978-951-652-211-4.

Synthesis Safety case for the disposal of spent nuclear fuel at Olkiluoto – Synthesis 2012. Eura-joki, Finland: Posiva Oy. POSIVA 2012-12. ISBN 978-951-652-193-3.

Terrain and Ecosystems Development Modelling Safety case for the disposal of spent nuclear fuel at Olkiluoto - Terrain and Ecosystems Development Modelling in the Biosphere Assessment BSA-2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-29. ISBN 978-951-652-210-7.

TURVA-2012 Portfolio SUPPORTING reports:

Backfill Production Line report Backfill Production Line 2012 - Design, Production and Initial State of the Deposition Tunnel Backfill and Plug. Eurajoki, Finland: Posiva Oy. POSIVA 2012-18. ISBN 978-951-652-199-5.

Biosphere Description Olkiluoto Biosphere Description 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-06. ISBN 978-951-652-187-2.

Buffer Production Line report Buffer Production Line 2012 - Design, Production and Initial State of the Buffer. Eura-joki, Finland: Posiva Oy. POSIVA 2012-17. ISBN 978-951-652-198-8.

Canister Production Line report Canister Production Line 2012 - Design, Production and Initial State of the Canister. Eurajoki, Finland: Posiva Oy. POSIVA 2012-16. ISBN 978-951-652-197-1.

Closure Production Line report Closure Production Line 2012 - Design, Production and Initial state of Closure. Eura-joki, Finland: Posiva Oy. POSIVA 2012-19. ISBN 978-951-652-200-8.

Site Description Olkiluoto Site Description 2011. Eurajoki, Finland: Posiva Oy. POSIVA 2011-02. ISBN 978-951-652-179-7.

Underground Openings Production Line report Underground Openings Production Line 2012 - Design, Production and Initial State of the Underground Openings. Eurajoki, Finland: Posiva Oy. POSIVA 2012-22. ISBN 978-951-652-203-9.

41

Other references:

Bronders, J., Patyn, J., Wemaere, I., Marivoet, J. 1994. Long term Performance Studies, Catalogue of Events, Features and Processes Potentially Relevant to Radioactive Waste Disposal in the Boom Clay Layer at the Mol Site. SCK-CEN Report R-2987 Annex. Mol, Belgium.

Chapman, N.A., Andersson, J., Robinson, P., Skagius, K., Wene, C-O., Wiborgh, M., Wingefors, S. 1995. Systems Analysis, Scenario Construction and Consequence Analy-sis Definition for SITE-94. SKI Report 95:26. Stockholm, Sweden: Swedish Nuclear Power Inspectorate.

DOE (U.S. Department of Energy) 1996. Title 40 CFR Part 191 Compliance Certifica-tion Application for the Waste Isolation Pilot Plant. DOE/CAO-1996-2184. Twenty-one volumes. Carlsbad, New Mexico: U.S. Department of Energy, Carlsbad Area Office.

Garisto, F. 2012. Fourth Case Study: Features, Events and Processes. Toronto, Canada: Nuclear Waste Management Organization (NWMO). NWMO TR-2012-14. 302 p.

Goodwin, B.W., Stephens, M.E., Davison, C.C., Johnson, L.H. & Zach, R. 1994. Sce-nario Analysis for the Postclosure Assessment of the Canadian Concept for Nuclear Fuel Waste Disposal. AECL-10969. Pinawa, Manitoba, Canada: AECL Research, Whiteshell Laboratories.

IAEA 2004. Safety Assessment Methodologies for Near Surface Disposal Facilities, ISAM, Vol. 1 — Review and enhancement of safety assessment approaches and tools, Vol. 2 — Test cases. Vienna, Austria: International Atomic Energy Agency (IAEA).

IAEA 2011. Disposal of Radioactive Waste – Specific Safety Requirements. Vienna, Austria: International Atomic Energy Agency (IAEA). IAEA Safety Standard Series No. SSR-5.

IAEA 2012. The Safety Case and Safety Assessment for the Disposal of Radioactive Waste – Safety Specific Guide. Vienna, Austria: International Atomic Energy Agency (IAEA). IAEA Safety Standard Series No. SSG-23.

Miller, B. & Marcos, N. 2007. Process Report. FEPs and scenarios for a spent fuel re-pository at Olkiluoto. Eurajoki, Finland: Posiva Oy. POSIVA 2007-12. 274 p. ISBN 978-951-652-162-9.

Miller, B., Savage, D., McEwen, T. & White, M. 2002. Encyclopaedia of Features, Events and Processes (FEPs) for the Swedish SFR and Spent Fuel Repositories, Pre-liminary Version. Stockholm, Sweden: Swedish Nuclear Power Inspectorate (SKI). SKI Report 02:35. 371 p. ISSN 1104-1374.

Miller, W.M. & Chapman, N.A. 1993. HMIP Assessment of Nirex Proposals, Identifi-cation of Relevant Processes (System Concept Group Report). London, UK: Her Maj-esty’s Inspectorate of Pollution (HMIP), Department of the Environment. Technical Report IZ3185-TR1 (Edition 1).

42

NAGRA 1994. Kristallin-I. Safety assessment report. Wettingen, Switzerland: NAGRA (National Cooperative for the Disposal of Radioactive Waste). Technical Report 93-22E. 430 p.

NEA 2006. The NEA International FEP Database: Version 2.1. Paris, France: OECD/Nuclear Energy Agency (NEA).

Posiva 2003. TKS-2003 Nuclear waste management of the Olkiluoto and Loviisa power plants: Programme for research, development and technical design for 2004-2006. Olkiluoto, Finland: Posiva Oy. TKS-2003. 288 p.

Posiva 2008. Safety Case Plan 2008. Eurajoki, Finland: Posiva Oy. POSIVA 2008-05. 80 p. ISBN 978-951-625-165-0.

Posiva 2009. Nuclear Waste Management at Olkiluoto and Loviisa Power Plants – Re-view of Current Status and Future Plans for 2010-2012. Eurajoki, Finland: Posiva Oy. TKS-2009. 532 p.

Posiva 2013. YJH-2012 Nuclear waste management at Olkiluoto and Loviisa power plants: Review of current status and future plans for 2013–2015. Eurajoki, Finland: Posiva Oy. YJH-2012. 363 p.

Rasilainen, K. (ed.) 2004. Localisation of the SR 97 Process Report for Posiva. Eura-joki, Finland: Posiva Oy. POSIVA 2004-05. 168p. ISBN 951-652-131-2.

SKB 2010a. FEP report for the safety assessment SR-Site. Stockholm, Sweden: Swed-ish Nuclear Fuel and Waste Management Co. (SKB). Technical Report TR-10-45. 288 p. ISSN 1404-0344.

SKB 2010b. Buffer, backfill and closure process report for the safety assessment SR-Site. Stockholm, Sweden: Swedish Nuclear Fuel and Waste Management Co. (SKB). Technical Report TR-10-47. 360 p. ISSN 1404-0344.

SKB 2010c. Geosphere process report for the safety assessment SR-Site. Stockholm, Sweden: Swedish Nuclear Fuel and Waste Management Co. (SKB). Technical Report TR-10-48. 271 p. ISSN 1404-0344.

STUK 2009. Säteilyturvakeskus esittelymuistio 31.10.2008/20.3.2009 H221/2. Ydinjät-teiden ja ydinmateriaalin valvonta. 4 p.

Vieno, T. & Ikonen, A.T.K. 2005. Plan for Safety Case of Spent Fuel Repository at Olkiluoto. Olkiluoto, Finland: Posiva Oy, POSIVA 2005-01.

Vieno, T. & Nordman, H. 1997. FEPs and scenarios. Auditing of TVO-92 and TILA-96 against international FEP database. Helsinki, Finland: Posiva Oy. POSIVA 97-11. 103 p. ISBN 951-652-036-7.

43

APPENDIX A. FULL TURVA-2012 FEP LIST

Table A-1. List of all FEPs considered in the TURVA-2012 safety case, i.e. including the features that have not been listed specifically in Table 2-1 of Features, Events and Processes. The codes of features (incl. system components) are presented here for the purposes of cross-checking in Appendices C and D.

Code Name Type Reference (in Features, Events and Processes)

Spent fuel FEPs

FU1 Spent fuel System component Table 2-2

FU1.1 Solid fuel matrix System component Table 3-4

FU1.2 Gaps System component Table 3-4

FU1.3 Water System component Table 3-4

FU1.4 Cladding and other Zircaloy-based materi-als

System component Table 3-4

FU1.5 Other metal parts System component Table 3-4

FU2.1 Radionuclide inventory Feature Table 3-2

FU2.2 Temperature Feature Table 3-2

FU2.3 Pressure Feature Table 3-2

FU2.4 Fuel geometry Feature Table 3-2

FU2.5 Mechanical stresses Feature Table 3-2

FU2.6 Material composition Feature Table 3-2

FU2.7 Water composition Feature Table 3-2

FU2.8 Gas composition Feature Table 3-2

3.2.1 Radioactive decay (and in-growth) Process Section 3.2.1

3.2.2 Heat generation Process Section 3.2.2

3.2.3 Heat transfer Process Section 3.2.3

3.2.4 Structural alteration of the fuel pellets Process Section 3.2.4

3.2.5 Radiolysis of residual water (in an intact canister)

Process Section 3.2.5

3.2.6 Radiolysis of the canister water Process Section 3.2.6

3.2.7 Corrosion of cladding tubes and metallic parts of the fuel assembly


3.2.8 Alteration and dissolution of the fuel matrix Process Section 3.2.8

3.2.9 Release of the labile fraction of the inven-tory


3.2.10 Production of helium gas Process Section 3.2.10

3.2.11 Criticality Process Section 3.2.11

3.3.1 Aqueous solubility and speciation Process Section 3.3.1

3.3.2 Precipitation and co-precipitation Process Section 3.3.2

3.3.3 Sorption Process Section 3.3.3

3.3.4 Diffusion in fuel pellets Process Section 3.3.4

Canister FEPs

44

CA1 Canister System component Table 2-2

CA1.1 Insert System component Table 4-4

CA1.2 Void spaces System component Table 4-4

CA1.3 Water System component Table 4-4

CA1.4 Overpack System component Table 4-4

CA2.1 Radionuclide inventory Feature Table 4-2

CA2.2 Temperature Feature Table 4-2

CA2.3 Pressure Feature Table 4-2

CA2.4 Canister geometry Feature Table 4-2

CA2.5 Mechanical stresses Feature Table 4-2

CA2.6 Material composition Feature Table 4-2

CA2.7 Water composition Feature Table 4-2

CA2.8 Gas composition Feature Table 4-2

4.2.1 Radiation attenuation Process Section 4.2.1


4.2.3 Deformation Process Section 4.2.3

4.2.4 Thermal expansion of the canister Process Section 4.2.4

4.2.5 Corrosion of the copper overpack Process Section 4.2.5

4.2.6 Corrosion of the cast iron insert Process Section 4.2.6

4.2.7 Stress corrosion cracking Process Section 4.2.7




4.3.4 Diffusion Process Section 4.3.4

4.3.5 Advection Process Section 4.3.5

4.3.6 Colloid transport Process Section 4.3.6

4.3.7 Gas transport Process Section 4.3.7

Buffer FEPs

BU1 Buffer System component Table 2-2

BU1.1 Bentonite System component Table 5-4

BU1.2 Void spaces System component Table 5-4

BU1.3 Pore water System component Table 5-4

BU2.1 Radionuclide inventory Feature Table 5-2

BU2.2 Temperature Feature Table 5-2

BU2.3 Swelling pressure Feature Table 5-2

BU2.4 Buffer geometry Feature Table 5-2

BU2.5 Water content Feature Table 5-2

BU2.6 Buffer composition Feature Table 5-2

BU2.7 Porewater composition Feature Table 5-2

BU2.8 Gas composition Feature Table 5-2


5.2.2 Water uptake and swelling Process Section 5.2.2

5.2.3 Piping and erosion Process Section 5.2.3

5.2.4 Chemical erosion Process Section 5.2.4

5.2.5 Radiolysis of porewater Process Section 5.2.5

45

5.2.6 Montmorillonite transformation Process Section 5.2.6

5.2.7 Alteration of accessory minerals Process Section 5.2.7

5.2.8 Microbial activity Process Section 5.2.8

5.2.9 Freezing and thawing Process Section 5.2.9








Tunnel backfill FEPs

BA1 Tunnel backfill System component Table 2-2

BA1.1 Swelling clay System component Table 6-4

BA1.2 Void spaces System component Table 6-4

BA1.3 Pore water System component Table 6-4

BA2.1 Radionuclide inventory Feature Table 6-2

BA2.2 Temperature Feature Table 6-2

BA2.3 Swelling pressure Feature Table 6-2

BA2.4 Backfill geometry Feature Table 6-2

BA2.5 Water content Feature Table 6-2

BA2.6 Backfill composition Feature Table 6-2

BA2.7 Porewater composition Feature Table 6-2

BA2.8 Gas composition Feature Table 6-2


6.2.2 Water uptake and swelling Process Section 6.2.2

6.2.3 Piping and erosion Process Section 6.2.3

6.2.4 Chemical erosion Process Section 6.2.4

6.2.5 Montmorillonite transformation Process Section 6.2.5

6.2.6 Alteration of accessory minerals Process Section 6.2.6










Auxiliary component FEPs

AU1 Auxiliary components System component Table 2-2

AU1.1 Plug or seal System component Table 7-4

AU1.2 Water System component Table 7-4

AU2.1 Radionuclide inventory Feature Table 7-2

46

AU2.2 Temperature Feature Table 7-2

AU2.3 Pressure Feature Table 7-2

AU2.4 Repository geometry Feature Table 7-2

AU2.5 Mechanical stresses Feature Table 7-2

AU2.6 Material composition Feature Table 7-2

AU2.7 Groundwater composition Feature Table 7-2

7.2.1 Chemical degradation Process Section 7.2.1

7.2.2 Physical degradation Process Section 7.2.2


7.3.1 Transport through auxiliary components Process Section 7.3.1

Geosphere FEPs

GE1 Geosphere System component Table 2-2

GE1.1 Rock matrix System component Table 8-3

GE1.2 Fractures and deformation zones System component Table 8-3

GE1.3 Groundwater (GW) System component Table 8-3

GE2.1 Radionuclide inventory Feature Table 8-1

GE2.2 Temperature Feature Table 8-1

GE2.3 Groundwater pressure Feature Table 8-1

GE2.4 Groundwater flux Feature Table 8-1

GE2.5 Rock stress Feature Table 8-1

GE2.6 Repository geometry Feature Table 8-1

GE2.7 Fracture geometry Feature Table 8-1

GE2.8 Rock matrix properties Feature Table 8-1

GE2.9 Fracture properties Feature Table 8-1

GE2.10 Groundwater composition Feature Table 8-1

GE2.11 Gas composition Feature Table 8-1


8.2.2 Stress redistribution Process Section 8.2.2

8.2.3 Reactivation-displacements along existing fractures


8.2.4 Spalling Process Section 8.2.4

8.2.5 Creep Process Section 8.2.5

8.2.6 Erosion and sedimentation in fractures Process Section 8.2.6

8.2.7 Rock-water interaction Process Section 8.2.7

8.2.8 Methane hydrate formation Process Section 8.2.8

8.2.9 Salt exclusion Process Section 8.2.9





8.3.4 Diffusion and matrix diffusion Process Section 8.3.4

8.3.5 Groundwater flow and advective transport Process Section 8.3.5



Surface environment FEPs

47

SU1 Surface environment System component Table 2-2

SU1.1 Terrestrial system Sub-system Table 9-1

SU1.1.1 Soil System component - Terrestrial sub-system

Table 9-2

SU1.1.2 Litter System component - Terrestrial sub-system

Table 9-2

SU1.1.3 Plants and mushroom System component - Terrestrial sub-system

Table 9-2

SU1.1.4 Animals System component - Terrestrial sub-system

Table 9-2

SU1.1.5 Livestock System component - Terrestrial sub-system

Table 9-2

SU1.1.6 Man System component - Terrestrial sub-system

Table 9-2

SU1.1.7 Atmosphere (local) System component - Terrestrial sub-system

Table 9-2

9.2.1 Erosion Process Section 9.2.11

9.2.2 Degradation Process Section 9.2.2

9.2.3 Podzolisation Process Section 9.2.3

9.2.4 Agriculture and aquaculture Process Section 9.2.4

9.2.5 Forest and peatland management Process Section 9.2.5

9.2.6 Infiltration Process Section 9.2.6

9.2.7 Groundwater discharge and recharge Process Section 9.2.7

9.2.8 Runoff Process Section 9.2.8

9.2.9 Drainage Process Section 9.2.9

9.2.10 Capillary rise Process Section 9.2.10

9.2.11 Uptake Process Section 9.2.11

9.2.12 Evapotranspiration Process Section 9.2.12

9.2.13 Translocation Process Section 9.2.13

9.2.14 Litterfall Process Section 9.2.14

9.2.15 Bioturbation Process Section 9.2.15

9.2.16 Migration of fauna Process Section 9.2.16

9.2.17 Senescence Process Section 9.2.17

9.2.18 Atmospheric deposition Process Section 9.2.18

9.2.19 Atmospheric resuspension Process Section 9.2.19



9.2.22 Gas origin and implications Process Section 9.2.22

9.2.23 Ingestion of food Process Section 9.2.23

9.2.24 Inhalation of air Process Section 9.2.24

9.2.25 Respiration Process Section 9.2.25

9.2.26 External radiation from the ground Process Section 9.2.26

9.2.27 Exposure from radiation sources Process Section 9.2.27

9.2.28 Topography Feature Section 9.2.28

9.2.29 Well Feature Section 9.2.29

9.2.30 Construction of a well Event Section 9.2.30

9.2.31 Food source potential Feature Section 9.2.31

48

9.2.32 Dietary profile Feature Section 9.2.32

9.2.33 Demographics Feature Section 9.2.33

9.2.34 Exposed population Feature Section 9.2.34

SU1.2 Aquatic system Sub-system Table 9-1

SU1.2.1 Sediment System component - Aquatic sub-system

Table 9-4

SU1.2.2 Water column System component - Aquatic sub-system

Table 9-4

SU1.2.3 Primary producers System component - Aquatic sub-system

Table 9-4

SU1.2.4 Other organisms System component - Aquatic sub-system

Table 9-4

SU1.2.5 Fish System component - Aquatic sub-system

Table 9-4

SU1.2.6 Other vertebrates System component - Aquatic sub-system

Table 9-4

SU1.2.7 Livestock System component - Aquatic sub-system

Table 9-4

SU1.2.8 Man System component - Aquatic sub-system

Table 9-4

SU1.2.9 Atmosphere (local) System component - Aquatic sub-system

Table 9-4

9.3.1 Terrestrialisation Process Section 9.3.1


9.3.3 Dispersion Process Section 9.3.3

9.3.4 Water exchange Process Section 9.3.4

9.3.5 Sedimentation and resuspension Process Section 9.3.5

9.3.6 Ingestion of drinking water Process Section 9.3.6

9.3.7 Flooding Event Section 9.3.7

9.3.8 Water source potential Feature Section 9.3.8

External FEPs

10.2.1 Climate evolution Process Section 10.2.1

10.2.2 Glaciation Process Section 10.2.2

10.2.3 Permafrost formation Process Section 10.2.3

10.2.4 Land uplift and depression Process Section 10.2.4

10.2.5 Inadvertent human intrusion Event Section 10.2.5

References

Features, Events and Processes Safety case for the disposal of spent nuclear fuel at Olkiluoto - Features, Events and Processes 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-07. ISBN 978-951-652-188-9.

49

APPENDIX B. MAPPING OF THE TURVA-2012 FEPS TO NEA FEPS AFTER SCREENING PROCESS

Table B-1. Component-wise mapping of TURVA-2012 FUEL FEPs to NEA FEPs (*NEA Version 2.1 Project Databases) screened “IN”. Checked by Barbara Pastina & Nuria Marcos.

Unique Number (NEA*)

NEA FEP names after initial aggregation (FUEL)

FUEL FEP name (TURVA-2012)

Explanatory note

W 2.061 Actinide sorption Sorption

W 2.090 Advection and dispersion NA Advection and dispersion within the component FUEL are disregarded as the proc-ess happens in other compo-nents

M 1.6.01

W 2.099 Alpha recoil Radioactive decay (and in-growth)

J 1.1.03

S 005 Changes in radionuclide inventory Radionuclide inventory

E SFR-22

E SFL-02

W 2.051 Chemical effects of corrosion NA The description of the proc-ess does not apply specifi-cally to the component FUEL but it is treated in interaction matrices

A 1.10

Chemical interactions Radiolysis of residual water (in an intact canister), Radiolysis of the canister water, Corrosion of cladding tubes and metallic parts of the fuel assembly, Alteration and dissolution of the fuel matrix, Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption

Chemical interactions in the component FUEL are related to all migration and evolution FEPs

I 039

A 1.11 Chemical kinetics Precipitation and co-precipitation, Alteration and dissolution of the fuel matrix, Aqueous solubility and speciation

K 1.21

Colloid formation NA See Table B-2; colloids are disregarded within the canis-ter, despite FEP 4.3.6 Colloid transport A 2.50

A 1.63

A 2.08

I 058

W 2.079

N 1.6.9

J 3.1.04

W 2.078 Colloid transport NA Colloid transport is disre-garded within the component FUEL as it happens outside of the component

S 008

J 5.45

E SFR-01 Colloid generation in the waste package

NA Merged within colloid forma-tion

W 2.081 Colloid sorption Sorption

50




Explanatory note

K 4.12 Colloids NA Merged within colloid forma-tion

A 1.13

A 3.026

E SFL-06 Colloids and particles in the canister

S 010

M 3.2.01 Corrosion of metal parts Corrosion of cladding tubes and metallic parts of the fuel assembly

S 012

A 1.26 Criticality Criticality

E SFL-12

J 1.1.01

S 017

I 081

H 1.3.2

K 0.4

M 3.4.03

W 2.014

J 1.3 Damaged or deviating fuel Structural alteration of the fuel pellets, Alteration and dissolution of the fuel matrix

S 019 Degradation of fuel elements Structural alteration of the fuel pellets, Alteration and dissolution of the fuel matrix

E SFL-13

A 1.27 Diffusion Diffusion in fuel pellets

A 2.16

E GEN-09

M 1.6.02

S 023

W 2.091

J 3.2.06

S 024

E SFL-15

E SFR-09

J 1.2.09 Dissolution of waste Alteration and dissolution of the fuel matrix

W 2.058

W 1.038 Effects of dissolution Precipitation and co-precipitation, Alteration and dissolution of the fuel matrix, Aqueous solubility and speciation

K 4.10 Elemental solubility/precipitation Aqueous solubility and speciation, Precipitation and co-precipitation

K 1.15

K 3.18

W 2.100 Enhanced diffusion Diffusion in fuel pellets

S 038 Fuel dissolution and conversion Alteration and dissolution of the fuel matrix

W 2.050 Galvanic coupling NA Galvanic coupling is disre-garded within the component FUEL

E SFL-22 Gap and grain boundary release Release of the labile fraction of

51




Explanatory note

S 039 the inventory

M 3.3.06

Gas effects Gas composition, Production of helium gas, Radiolysis of residual water

A 1.35

J 1.2.04

Gas generation Gas composition, Radiolysis of residual water (in an intact canis-ter), Production of helium gas

A 1.35

I 015 Gas generation (CH4, CO2, H2) NA The description of the proc-ess does not apply specifi-cally to the component FUEL but it is treated in interaction matrices. Merged with gas generation in the repository.

E SFR-11 Gas generation in the repository

J 1.1.04 Gas generation: He production Production of helium gas

K 1.24

W 2.054

K 5.17 Gas pressure effects NA Specific FEPs disregarded within the component FUEL

K 6.17

K 0.3 Gaseous and volatile isotopes Release of the labile fraction of the inventory

A 2.27 Gases and gas transport Gas composition

W 2.049 Gases from metal corrosion Gas composition, Corrosion of cladding tubes and metallic parts of the fuel assembly

A 1.37 Geochemical pump Sorption, Aqueous solubility and speciation, Precipitation and co-precipitation

W 2.013 Heat from radioactive decay Heat generation

K 1.08

H 1.2.1 Hydrogen by metal corrosion Corrosion of cladding tubes and metallic parts of the fuel assembly

K 2.16 Hydrogen production This FEP is not FUEL specific but treated in the component CANISTER

J 1.2.05 I, Cs-migration to fuel surface Structural alteration of the fuel pellets, Diffusion in fuel pellets, Release of the labile fraction of the inventory

S 050

M 3.1.05 Induced chemical changes NA The description of the proc-ess does not apply specifi-cally to the component FUEL but it is treated in interaction matrices

S 051 Interaction with corrosion products Corrosion of cladding tubes and metallic parts of the fuel assembly

M 3.2.02 Interactions of host materials and ground water with repository materi-als

Release of the labile fraction of nuclides

The description of the proc-ess does not apply specifi-cally to the component FUEL but it is treated in interaction matrices

N 3.2.3

J 3.1.10 Interactions with corrosion products and waste

Corrosion of cladding tubes and metallic parts of the fuel assembly

52




Explanatory note

J 2.1.03 Internal corrosion due to waste NA The description of the proc-ess does not apply specifi-cally to the component FUEL but it is treated in interaction matrices

E SFL-29 Internal gas pressure NA The description of the proc-ess does not apply specifi-cally to the component FUEL but it is treated in interaction matrices

J 2.3.08

S 053

W 2.060 Kinetics of precipitation and dissolu-tion

Alteration and dissolution of the fuel matrix, Aqueous solubility and speciation, Precipitation and co-precipitation

W 2.062 Kinetics of sorption Sorption

W 2.057 Kinetics of speciation Aqueous solubility and speciation

K 2.07 Localised corrosion Corrosion of cladding tubes and metallic parts of the fuel assembly

W 2.067 Localized reducing zones Alteration and dissolution of the fuel matrix

A 1.51 Long-term physical stability Alteration and dissolution of the fuel matrix

A 1.52 Long-term transients All evolution and migration related FEPs

M 1.6.13 Mass, isotopic and species dilution Alteration and dissolution of the fuel matrix

M 3.4.02 Material propertiy changes Structural alteration of the fuel pellets, Corrosion of the cladding tubes and metallic parts of the fuel assembly

K 5.10 Non-linear sorption Sorption

K 6.10

K 5.21 Organics NA The description does not apply to the component FUEL but the presence of organic materials in the near field potentially forming colloids is treated in interaction matri-ces

K 6.21

J 4.1.02 pH-deviations Water composition

W 2.059 Precipitation Precipitation and co-precipitation

W 2.059

A 1.62 Precipitation and dissolution Alteration and dissolution of the fuel matrix, Aqueous solubility and speciation, Precipitation and co-precipitation

A 2.49

S 060

I 045 Progency nuclides (critical radionu-clides)

Radionuclide inventory, Radioac-tive decay (and ingrowth)

A 1.64 Radiation damage Structural alteration of the fuel pellets, corrosion of the cladding tubes and metallic parts of the fuel assembly

I 238

E SFR-14

A 1.65 Radioactive decay and ingrowth Radioactive decay (and in-growth)

A 2.51

A 3.082

53




Explanatory note

E GEN-28

K 0.1

H 1.3.1

M 3.4.04

W 2.012

S 069

S 070 Radioactive decay of mobile nu-clides

Radioactive decay (and in-growth)

J 1.1.02 Radioactive decay; heat Heat generation

H 1.2.4 Radioactive gases Gas composition, Release of the labile fraction of the inventory

W 2.055

W 2.015 Radiological effects on waste Structural alteration of the fuel pellets, Corrosion of the cladding tubes and metallic parts of the fuel assembly

A 1.66 Radiolysis Radiolysis of residual water (in an intact canister), Radiolysis of the canister water

E GEN-30

J 1.2.01

J 3.1.09

K 1.23

K 3.19

M 3.4.01

S 071

E SFL-37

S 072

E SFL-27 Radionuclide accumulation at the spent fuel surface

Diffusion in fuel pellets

E SFL-28 Radionuclide interaction with corro-sion products

Precipitation and co-precipitation, Aqueous solubility and speciation, Alteration and dissolution of the fuel matrix, Sorption

K 1.02 Radionuclide inventory Radionuclide inventory

W 2.002

A 1.50

K 4.08 Radionuclide migration Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion in fuel pellets

K 2.20

E GEN-27 Radionuclide precipitation and disso-lution

Alteration and dissolution of the fuel matrix, Aqueous solubility and speciation, Precipitation and co-precipitation

E GEN-31 Radionuclide reconcentration Precipitation and co-precipitation

E SFL-41 Radionuclide release from the metal non-fuel parts

Corrosion of cladding tubes and metallic parts of the fuel assembly

E SFL-40 Radionuclide release from the spent fuel matrix

Alteration and dissolution of the fuel matrix

E SFR-15 Radionuclide release from the waste Alteration and dissolution of the fuel matrix, Release of the labile fraction of the inventory

E SFR-18

K 4.09 Radionuclide retardation Precipitation and co-precipitation,

54




Explanatory note

K 3.10 Sorption

E GEN-34 Radionuclide sorption (near field - far field)

Sorption

K 7.09

K 2.15 Radionuclide sorption and co-precipitation

Sorption, Precipitation and co-precipitation

K 1.20 Radionuclide source term Spent nuclear fuel, Aqueous solubility and speciation, Precipi-tation and co-precipitation

J 3.1.11 Redox front Alteration and dissolution of the fuel matrix

S 074

E SFL-38

W 2.065

J 1.2.08 Redox potential NA The description of the proc-ess does not apply specifi-cally to the component FUEL but it is treated in interaction matrices (can be mapped to GEOSPHERE feature Groundwater composition)

W 2.066 Reduction-oxidation kinetics Alteration and dissolution of the fuel matrix

S 076 Release from fuel matrix Alteration and dissolution of the fuel matrix

S 077 Release from metal parts Corrosion of cladding tubes and metallic fuel assembly parts

K 8.18 Secular equilibrium of radionuclide chains

Radioactive decay (and in-growth)

J 5.44 Solubility and precipitation Aqueous solubility and speciation, Precipitation and co-precipitation

M 1.6.06 Solubility limit Aqueous solubility and speciation, Precipitation and co-precipitation

K 5.16 Solubility limits/colloid formation Aqueous solubility and speciation

K 6.16

J 1.2.06 Solubility within fuel matrix Alteration and dissolution of the fuel matrix

W 2.077 Solute transport Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion in fuel pellets

A 1.73 Sorption Sorption

A 2.62

J 4.1.04

K 5.09

K 6.09

M 1.6.07

S 084

A 2.63 Sorption - nonlinear Sorption

A 1.74

S 085 Sorption on filling material Sorption

55




Explanatory note

I 233 Source term & solubility limits Radionuclide inventory, Precipita-tion and co-precipitation, Aque-ous solubility and speciation

A 1.75 Source terms (expected) Radionuclide inventory

A 1.76 Source terms (other) Radionuclide inventory, Radioac-tive decay (and ingrowth)

A 1.77 Speciation Aqueous solubility and speciation

A 2.64

K 0.2

W 2.056

E SFL-21 Spent fuel dissolution and conver-sion

Alteration and dissolution of the fuel matrix

A 1.79 Stability of UO2 Alteration and dissolution of the fuel matrix

J 3.2.07 Swelling of corrosion products Corrosion of cladding tubes and metallic parts of the fuel assembly

W 1.060 Temperature Temperature Temperature is a feature that influences and is influenced by all the FEPs related to the component FUEL

A 1.81 Temperature effects Temperature, Heat generation, Heat transfer

E SFL-46 Temperature of the near-field Temperature, Heat generation, Heat transfer

E SFR-17

I 300 Termperature effects (on transport) Temperature, Heat generation, Heat transfer

W 2.029 Thermal effects on material proper-ties

Temperature, Heat generation, Heat transfer

H 1.6.3 Thermal effects: Chemical and microbiological changes


H 1.6.4 Thermal effects: Transport (diffu-sion) effects


K 3.02 Thermal evolution Temperature, Heat generation, Heat transfer

J 4.1.07 Thermo-chemical effects Temperature, Heat generation, Heat transfer

H 1.2.8

J 4.2.07 Thermo-hydro-mechanical effects Temperature, Heat generation, Heat transfer

S 095 Total release from fuel elements Alteration and dissolution of the fuel matrix, Release of the labile fraction of the inventory, Corro-sion of the tubes and metallic parts of the fuel assembly

E SFL-48

A 1.84 Transport in gases or of gases NA Within the component FUEL, gas generation is treated but not gas transport or any kind of transport other than diffu-sion, it is assumed that the gas is immediately trans-ported out of the fuel

H 1.5.5 Transport of chemically-active sub-stances into the near-field

NA

W 2.089 Transport of radioactive gases NA

H 1.5.3 Unsaturated flow due to gas produc-tion

Gas composition, Production of helium gas, Corrosion of the insert, Release of the labile frac-tion of the inventory

Within the component FUEL gas generation is treated but not gas transport, it is as-sumed that the gas is imme-diately transported out of the fuel

I 317 Unsaturated transport Gas composition, Production of

56




Explanatory note

A 1.88 helium gas, Corrosion of the insert, release of the labile frac-tion of the inventory

H 1.1.3 Waste corrosion and solubility and speciation of radionuclides

Structural alteration of the fuel pellets, Alteration and dissolution of the fuel matrix, Aqueous solu-bility and speciation

I 337 Water contacting waste in vault NA This is not a feature of the component FUEL, but can be mapped to the GEOSPHERE feature Groundwater compo-sition

S 100 Volume increase of corrosion prod-ucts

NA The description of the proc-ess does not apply to the component FUEL but it is treated in interaction matrices

Table B-2. Component-wise mapping of TURVA-2012 CANISTER FEPs to NEA FEPs (*NEA Version 2.1 Project Databases) screened “IN”. Checked by Barbara Pastina and Nuria Marcos.


NEA FEP names after initial aggregation (CANISTER)

CANISTER FEP name (TURVA-2012)

Explanatory note


W 2.090 Advection and dispersion Advection

M 1.6.01

K 2.06 Anoxic corrosion Corrosion of the copper overpack, Corrosion of the cast iron insert

W 2.088 Biofilms Corrosion of the copper overpack

A 1.03 Biological activity Corrosion of the copper overpack, Corrosion of the cast iron insert

Relates to corrosion

I 012

E SFL-10 Canister corrosion prior to wetting Corrosion of the copper overpack, Corrosion of the cast iron insert

K 2.19 Canister temperature Temperature

K 2.02 Canister thickness Canister geometry

K 3.14 Fe-clay interaction NA This FEP is disregarded within the component CAN-ISTER. Treated within the component BUFFER and in interaction matrices.

J 5.23 Changed hydrostatic pressure on canister

Pressure, Deformation

K 2.14 Chemical buffering (canister corro-sion products)

Corrosion of the copper overpack, Corrosion of the cast iron insert

W 2.051 Chemical effects of corrosion Corrosion of the copper overpack, Corrosion of the cast iron insert

A 1.10 Chemical interactions All CANISTER FEPs Chemical interactions in the component CANISTER are related to all migration and evolution FEPs in this com-

57




Explanatory note

ponent

A 1.11 Chemical kinetics Precipitation and co-precipitation, Aqueous solubility and speciation

J 2.1.01 Chemical reactions (copper corro-sion)

Corrosion of the copper overpack

K 1.21 Colloid formation NA Colloid formation is ad-dressed in the component BUFFER A 2.08

I 058

W 2.079

N 1.6.9

J 3.1.04

W 2.078 Colloid transport Colloid transport Colloid transport is also addressed in the components BUFFER, BACKFILL, GEO-SPHERE

S 008

J 5.45

E SFR-01 Colloid generation in the waste package

NA This FEP is disregarded within the component CAN-ISTER. Treated within other components.

W 2.081 Colloid sorption NA Colloid sorption is treated in other components

K 4.12 Colloids NA Colloids are disregarded within the component CAN-ISTER. They are addressed in the components BUFFER, BACKFILL, GEOSPHERE

A 1.13

A 3.026

E SFL-06 Colloids and particles in the canis-ter

S 010

J 4.1.03 Colloids, complexing agents

A 2.09 Complexation by organics NA This FEP is disregarded within the component CAN-ISTER. Treated within other components.

A 1.14

A 1.16 Container corrosion products Corrosion of the copper overpack, Corrosion of the cast iron insert

W 2.004 Container form Canister, Canister materials, geometry

A 1.20 Container healing NA This FEP is disregarded within the component CAN-ISTER, buffer penetration in a canister defect is treated in the component BUFFER (water uptake and swelling)

W 2.034 Container integrity Deformation, Thermal expansion of the canister, Corrosion of the copper overpack, Corrosion of the cast iron insert, Stress corrosion cracking

W 2.005 Container material inventory Canister geometry, Material composition

A 1.21 Containers - partial corrosion Corrosion of the copper overpack, Corrosion of the cast iron insert

58




Explanatory note

A 1.24 Corrosion Corrosion of the copper overpack, Corrosion of the cast iron insert

I 126 Corrosion (galvanic coupling) Corrosion of the copper overpack, Corrosion of the cast iron insert

S 011 Corrosion of copper canister Corrosion of the copper overpack

E SFL-07

M 3.2.01 Corrosion of metal parts Corrosion of the copper overpack, Corrosion of the cast iron insert

S 012

E SFL-09 Corrosion of the cast iron insert Corrosion of the cast iron insert

E SFL-08

K 2.03 Corrosion on wetting Corrosion of the copper overpack, Corrosion of the cast iron insert

S 014 Corrosion prior to wetting Corrosion of the copper overpack, Corrosion of the cast iron insert

K 2.18 Corrosion products (physical ef-fects)


J 2.1.08 Corrosive agents, Sulphides, oxy-gen etc


J 2.3.06 Cracking along welds Deformation, Stress corrosion cracking

J 2.2 Creeping of steel/copper Deformation, Stress corrosion cracking

S 016

E SFL-11

E SFL-14 Different thermal expansion and contraction of the near-field barriers

Thermal expansion of the canister

M 3.1.01

S 022

W 2.031

A 1.27 Diffusion Diffusion

A 2.16

E GEN-09

M 1.6.02

S 023

W 2.091

J 3.2.06

S 024

E SFL-15

E SFR-09

W 2.048 Effect of biofilms on microbial gas generation


K 2.17 Effect of hydrogen on corrosion Corrosion of the cast iron insert

W 2.064 Effect of metal corrosion Corrosion of the copper overpack, Corrosion of the cast iron insert

59




Explanatory note

W 2.047 Effect of radiation on microbial gas generation


W 2.045 Effect of temperature on microbial gas generation

Temperature

W 1.038 Effects of dissolution Aqueous solubility and speciation, Precipitation and co-precipitation

J 2.3.02 Electrochemical effects/gradients Corrosion of the copper overpack, Corrosion of the cast iron insert

W 2.094

E GEN-13

H 1.1.4

S 029

A 1.30


K 1.15

K 3.18

M 3.3.03 Embrittlement and cracking Corrosion of the copper overpack, corrosion of the cast iron insert, Deformation

W 2.100 Enhanced diffusion Diffusion

E SFL-52 Evolving water chemistry in the canister

Water composition

E SFL-51 Expansion of solid corrosion prod-ucts

Thermal expansion of the canis-ter, Corrosion of the copper overpack, Corrosion of the cast iron insert

E SFL-19 Failure of the cast iron insert Deformation, Corrosion of the cast iron insert

E SFL-18 Failure of the copper shell Deformation, Corrosion of the copper overpack

A 1.35 Formation of gases Corrosion of the copper overpack, Corrosion of the cast iron insert

W 2.050 Galvanic coupling Corrosion of the cast iron insert, Corrosion of the copper overpack

M 3.3.06 Gas effects NA The description of the proc-ess does not apply specifi-cally to the component CAN-ISTER but it is treated in interaction matrices

S 040 Gas escape from canister Gas transport

E SFL-23

J 1.2.04 Gas generation Corrosion of the cast iron insert

I 015 Gas generation (CH4, CO2, H2) Corrosion of the cast iron insert

S 045 Gas generation in the canister Corrosion of the cast iron insert

E SFL-25

E SFR-11 Gas generation in the repository Corrosion of the cast iron insert, Gas transport

This is a general FEP merged and embedded with other related gas generation and transport

60




Explanatory note

M 1.6.04 Gas mediated transport Gas transport

K 5.17 Gas pressure effects Gas transport

K 6.17

H 1.2.6 Gas transport Gas transport

J 6.02

K 4.11 Gas transport/dissolution Gas transport

A 2.27 Gases and gas transport Gas composition, Gas transport

W 2.049 Gases from metal corrosion Corrosion of the cast iron insert

A 1.37 Geochemical pump Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion

A 1.42 Hydride cracking Stress corrosion cracking

H 1.2.1 Hydrogen by metal corrosion Corrosion of the copper overpack, Corrosion of the cast iron insert

K 2.16 Hydrogen production Corrosion of the copper overpack, corrosion of the cast iron insert

J 2.3.07.2 Hydrostatic pressure on canister Pressure, Deformation

M 3.1.05 Induced chemical changes Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion

S 051 Interaction with corrosion products Sorption, Precipitation and co-precipitation

M 3.2.02 Interactions of host materials and ground water with repository mate-rials

NA Not a specific FEP within the component CANISTER - though relates to corrosion; dealt with in interaction matri-ces

N 3.2.3


NA Not a specific FEP within the component canister – though relates to corrosion, interac-tions are dealt with in interac-tion matrices

J 2.1.03 Internal corrosion due to waste Corrosion of the cast iron insert

E SFL-29 Internal gas pressure Gas composition, Pressure

J 2.3.08

S 053


Aqueous solubility and speciation, Precipitation and co-precipitation



K 2.07 Localised corrosion Corrosion of the copper overpack

W 2.067 Localized reducing zones NA Not a specific FEP within the component CANISTER; dealt with in the component GEO-SPHERE in Site Description

A 1.51 Long-term physical stability Deformation, Thermal expansion of the canister, Corrosion of the copper overpack, Corrosion of the

61




Explanatory note

cast iron insert

A 1.52 Long-term transients Relates to all FEPs within the component CANISTER

J 2.3.04 Loss of ductility Deformation, Corrosion of the copper overpack, Corrosion of the insert

M 1.6.13 Mass, isotopic and species dilution NA Not a specific FEP within the component CANISTER - relates to FUEL

M 3.4.02 Material property changes Radiation attenuation

S 055 Mechanical impact on canister Deformation, Thermal expansion of the canister, Corrosion of the copper overpack, Corrosion of the cast iron insert, Stress corrosion cracking

E SFL-30 Mechanical impact on the canister

E SFR-13 Mechanical impact on the engi-neered barriers

K 2.05 Microbially-mediated corrosion Corrosion of the copper overpack

J 3.2.02 Movement of canister in buffer/backfill

NA Not an individual FEP but interaction between canister and buffer. Dealt with in Performance Assessment.

S 058

W 2.033

E SFL-33


K 6.10

K 5.21 Organics NA Not a specific FEP within the component CANISTER; organics are dealt with in connection with other compo-nents (e.g. BUFFER, BACK-FILL) and in interaction matri-ces)

K 6.21

K 2.10 Other canister degradation proc-esses

Radiation attenuation, Deforma-tion

K 2.04 Oxic corrosion Corrosion of the copper overpack

J 4.1.01 Oxidizing conditions Corrosion of the copper overpack

J 4.1.02 pH-deviations Water composition

A 1.60 Pitting Corrosion of the copper overpack

J 2.1.07


W 2.059

A 1.62 Precipitation and dissolution Aqueous solubility and speciation, Precipitation and co-precipitation

A 2.49

S 060

S 061 Preferential pathways in canister Corrosion of the copper overpack. Corrosion of the cast iron insert

E SFL-34

S 063 Properties of failed canister Canister, Overpack, Deformation, Corrosion of the copper overpack,

62




Explanatory note

Corrosion of the cast iron insert

A 2.50 Pseudo-colloids NA Not a specific FEP within the component CANISTER; pseudo-colloids are dealt with in connection with groundwa-ter composition

A 1.63

A 1.64 Radiation damage Radiation attenuation

I 238

E SFR-14

J 2.3.05 Radiation effects on canister Radiation attenuation

S 068

E SFL-36

W 2.016

K 2.11 Radiation shielding Radiation attenuation

H 1.2.4 Radioactive gases NA Not a specific FEP within the component CANISTER. Related to the component FUEL

W 2.055

A 1.66 Radiolysis NA Not a specific FEP related to the component CANISTER. Related to the component FUEL.

E GEN-30

J 1.2.01

J 3.1.09

K 1.23

K 3.19

M 3.4.01

S 071

E SFL-37

S 072

E SFL-28 Radionuclide interaction with corro-sion products

Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion

K 4.08 Radionuclide migration Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion, Advection, Colloid transport, Gas transport

K 2.20

E GEN-27 Radionuclide precipitation and dissolution



E SFL-41 Radionuclide release from the metal non-fuel parts

NA Not a specific FEP related to the component CANISTER. Related to the component FUEL.

K 4.09 Radionuclide retardation Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion

K 3.10

E GEN-34 Radionuclide sorption (near field - Sorption

63




Explanatory note

K 7.09 far field)



E SFL-49 Radionuclides release and trans-port from the canister

Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion, Advection, Colloid transport, Gas transport

J 3.1.11 Redox front NA Not a specific FEP related to the component CANISTER. Related to the component FUEL.

S 074

E SFL-38

W 2.065

J 1.2.08 Redox potential Water composition

S 075 Reduced mechanical strength of the canister

Deformation

E SFL-39

W 2.066 Reduction-oxidation kinetics Water composition

J 1.5 Release of radionuclides from the failured canister

Advection, Diffusion

K 2.13 Residual canister (crack/hole ef-fects)

Canister geometry

J 2.1.05 Role of chlorides in copper corro-sion


J 2.1.04 Role of the eventual channeling within the canister

Advection


M 1.6.06 Solubility limit Aqueous solubility and speciation, Precipitation and co-precipitation

K 5.16 Solubility limits/colloid formation Aqueous solubility and speciation, Colloid transport

K 6.16

W 2.077 Solute transport Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion, Advection


A 2.62

J 4.1.04

K 5.09

K 6.09

M 1.6.07

S 084


A 1.74

S 085 Sorption on filling material Sorption

I 233 Source term & solubility limits Radionuclide inventory,

Aqueous solubility and speciation

Relates also to FUEL and BUFFER

64




Explanatory note


A 2.64

K 0.2

W 2.056

K 2.09 Stress corrosion cracking Stress corrosion cracking

J 2.3.03

W 2.082 Suspensions of particles NA Not a specific FEP within the component CANISTER; suspension of particles is dealt with in colloid transport

J 3.2.07 Swelling of corrosion products Corrosion of the copper overpack, Corrosion of the cast iron insert

W 1.060 Temperature Temperature, Heat transfer, Thermal expansion of the canister

A 1.81 Temperature effects

E SFL-46 Temperature of the near-field

E SFR-17

S 090 Temperature, canister

I 300 Temperature effects (on transport)

J 2.3.01 Thermal cracking




K 3.02 Thermal evolution

J 4.1.07 Thermo-chemical effects All CANISTER FEPs Relates to all FEPs within the component CANISTER

H 1.2.8

J 4.2.07 Thermo-hydro-mechanical effects All CANISTER FEPs Relates to all FEPs within the component CANISTER

K 2.08 Total corrosion rate Corrosion of the copper overpack

S 097 Transport and release of nuclides, failed canister

Diffusion, Advection

A 1.84 Transport in gases or of gases Gas transport

H 1.5.5 Transport of chemically-active substances into the near-field

Diffusion, Advection

W 2.089 Transport of radioactive gases Gas transport

A 1.86 Uniform corrosion Corrosion of the copper overpack

H 1.5.3 Unsaturated flow due to gas pro-duction

NA Not a specific FEP within the component CANISTER; unsaturated flow and trans-port is dealt with Advection and Groundwater flow and advective transport

I 317 Unsaturated transport

A 1.88

I 066 Waste container (corro-sion/collapse)

Canister, Overpack, Deformation, Thermal expansion of the canis-

65




Explanatory note

ter, Corrosion of the copper overpack, Corrosion of the cast iron insert, Stress corrosion cracking

I 065 Waste container (metal corrosion products)

Corrosion of the copper overpack, Corrosion of the cast iron insert, Sorption

S 102 Water chemistry, canister Water composition

E SFL-57 Water turnover in the cast iron insert

NA Not a specific FEP within the component CANISTER - interactions dealt with in Performance Assessment

E SFL-56 Water turnover in the copper shell

S 105 Water turnover, copper canister

I 039 Vault chemical interactions



Table B-3. Component-wise mapping of TURVA-2012 BUFFER FEPs to NEA FEPs (*NEA Version 2.1 Project Databases) screened “IN”. Checked by Heini Laine & Nu-ria Marcos


NEA FEP names after initial aggregation (BUFFER)

BUFFER FEP name (TURVA-2012)

Explanatory note



M 1.6.01

E GEN-02 Anion exclusion Diffusion, Sorption Anions do not sorb in clays (mostly)

S 002

K 3.13 Bentonite cementation Montmorillonite transformation, Alteration of accessory minerals

K 3.06 Bentonite erosion Piping and erosion, Chemical ero-sion

K 3.05 Bentonite plasticity Swelling pressure This is a property or a feature

K 3.09 Bentonite porewater chemistry Porewater composition

K 3.03 Bentonite saturation Water uptake and swelling

K 3.04 Bentonite swelling pressure Water uptake and swelling, Swell-ing pressure

A 1.80

I 298

S 003 Bentonite swelling, buffer Water uptake and swelling

J 3.2.01.1

E SFL-01

W 2.088 Biofilms Microbial activity

A 1.03 Biological activity

66




Explanatory note

I 012

I 027 Piping Piping and erosion

I 048 Cement-clay interaction Montmorillonite transformation, Alteration of accessory minerals

K 3.25

K 3.01 Bentonite/buffer emplacement and composition

Buffer, Buffer composition

I 028b

A 1.06

A 1.07 Buffer evolution All FEPs in BUFFER

K 3.08 Buffer impermeability Water uptake and swelling

I 028a Buffer cementation Montmorillonite transformationAlteration of accessory minerals

K 3.14 Fe-clay interaction Montmorillonite transformation,Alteration of accessory minerals

A 2.06 Cavitation Piping and erosion

W 2.063 Changes in sorptive surfaces Sorption

S 006 Chemical alteration of the buffer and backfill

Montmorillonite transformation, Alteration of accessory minerals

E SFL-03

W 2.051 Chemical effects of corrosion Montmorillonite transformation, Alteration of accessory minerals

N 1.6.14 Chemical gradients Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion, Montmorillonite transformation, Alteration of acces-sory minerals

A 1.09

W 2.097

M 1.6.14

A 1.10 Chemical interactions Porewater composition, Buffer composition

A 1.11 Chemical kinetics Porewater composition, Buffer composition, Sorption, Precipitation and co-precipitation, Diffusion, Aqueous solubility and speciation

E SFL-04 Coagulation of bentonite Porewater composition

J 3.1.05

S 007

E SFL-05 Colloid behaviour in the buffer and backfill

Colloid transport

W 2.080 Colloid filtration Colloid transport

E SFR-10

K 1.21 Colloid formation Colloid transport

A 2.08

I 058

W 2.079

N 1.6.9

67




Explanatory note

J 3.1.04

W 2.078 Colloid transport Colloid transport

S 008

J 5.45

S 009 Colloid generation-source Colloid transport

W 2.081 Colloid sorption Colloid transport

K 4.12 Colloids Colloid transport

A 1.13

A 3.026

J 4.1.03 Colloids, complexing agents Colloid transport

A 2.09 Complexation by organics Aqueous solubility and speciation, Buffer, buffer composition

A 1.14

N 1.6.10 Complexing agents Buffer, Buffer composition

J 4.1.09

W 2.043 Convection Heat transfer

A 1.22

A 2.11

J 2.1.08 Corrosive agents, Sulphides, oxygen, etc.

Buffer composition

M 1.2.14 Decrease of plasticity of the clay Montmorillonite transformation

J 3.1.01 Degradation of the bentonite by chemical reactions



A 2.16

E GEN-09

M 1.6.02

S 023

W 2.091

J 3.2.06

S 024

E SFL-15

E SFR-09

S 025 Dilution of buffer/backfill Chemical erosion

E SFL-16

A 1.28 Dispersion Chemical erosion, Piping and ero-sion

A 2.18

A 3.042

68




Explanatory note

J 6.04

S 026

K 4.04 Effect of bentonite swelling on EDZ

Water uptake and swelling


Microbial activity


Microbial activity


Microbial activity

J 3.1.03 Effects of bentonite on groundwa-ter chemistry

NA Not a FEP in itself but taken into account in coupling with other components

W 1.038 Effects of dissolution Chemical erosion


K 1.15

K 3.18


J 3.2.04 Erosion of buffer/backfill Piping and erosion, Chemical ero-sion

S 031

E SFL-17

E SFL-53 Evolving water chemistry in the buffer

Porewater composition

J 3.2.09 Flow through buffer/backfill Piping and erosion, Advection

S 037

A 1.34 Formation of cracks Water uptake and swelling

A 1.35 Formation of gases NA Not a specific FEP within the component BUFFER. Dealt with in e.g. the component CANISTER

I 268 Freeze/thaw cycles Freezing and thawing

M 3.3.06 Gas effects Gas transport

S 041 Gas flow through the buffer and backfill

E SFL-24

J 3.2.12

M 1.6.04 Gas mediated transport

K 3.15 Gas permeability

K 5.17 Gas pressure effects

K 6.17

H 1.2.6 Gas transport

J 6.02

K 4.11 Gas transport/dissolution

69




Explanatory note

A 2.27 Gases and gas transport

K 5.04 Groundwater flow path NA Not a specific FEP within the component BUFFER; Dealt with in the component GEO-SPHERE.

A 1.40 Hydraulic conductivity Water uptake and swelling

A 2.35 Hydraulic properties - evolution NA Not a specific FEP within the component BUFFER. Dealt with in the component GEO-SPHERE.

E SFL-42 Hydraulic resaturation of the buffer and backfill


E SFR-16 Hydraulic resaturation of the near-field


A 1.43 Hydrothermal alteration Montmorillonite transformation, Alteration of accessory minerals

M 3.1.05 Induced chemical changes Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Montmorillonite transfor-mation, Alteration of accessory minerals

K 3.21 Inhomogeneities (properties and evolution)

Buffer, Buffer composition

S 051 Interaction with corrosion prod-ucts


M 3.2.02 Interactions of host materials and ground water with repository materials

Chemical erosion, Montmorillonite transformation, Alteration of acces-sory minerals

N 3.2.3

J 3.1.10 Interactions with corrosion prod-ucts and waste


W 2.060 Kinetics of precipitation and dissolution




W 2.067 Localized reducing zones NA Not a specific FEP within the component BUFFER. Dealt with in the component GEO-SPHERE in Site Description

A 1.51 Long-term physical stability Piping and erosion, Chemical ero-sion, Freezing and thawing

A 1.52 Long-term transients All BUFFER related FEPs

M 1.6.13 Mass, isotopic and species dilu-tion

NA Not a specific FEP within the component BUFFER. Dealt with in the component FUEL and related to aqueous solu-bility and speciation in all components.

M 3.4.02 Material propertiy changes Radiolysis of porewater


Piping and erosion, Freezing and thawing

H 1.2.2 Methane and carbon dioxide by microbial degradation

NA Not a specific FEP within the component BUFFER. Related to the component GEO-SPHERE. Dealt with in Site Description.

70




Explanatory note

A 2.45 Microbial activity Microbial activity

A 1.54

J 2.1.10

W 1.071

K 5.22

K 6.22

K 1.22

K 3.17

S 057

E SFL-32

M 3.2.07

N 3.2.7

A 1.55

W 2.087 Microbial transport Microbial activity, Colloid transport

K 3.12b Mineralogical alteration - long term


K 3.12a Mineralogical alteration - short term


J 3.2.02 Movement of canister in buffer/backfill

Swelling pressure, Water uptake and swelling, Buffer geometry

J 3.1.08 Near field buffer chemistry Buffer composition, Porewater composition, Gas composition


K 6.10

W 2.068 Organic complexation Aqueous solubility and speciation

W 2.069 Organic ligands Aqueous solubility and speciation, Sorption

K 5.21 Organics Buffer composition

K 6.21

J 3.1.12 Perturbed buffer material chemis-try


J 4.1.02 pH-deviations Porewater composition


A 1.62 Precipitation and dissolution Precipitation and co-precipitation, Aqueous solubility and speciation

A 2.49

S 060

J 3.2.08 Preferential pathways in the buffer/backfill

Piping and erosion, Advection

S 062 Properties of bentonite buffer Bentonite, Temperature, Swelling pressure, Buffer geometry, Water content, Buffer composition, Pore-water composition, Gas composi-tion

71




Explanatory note

A 2.50 Pseudo-colloids Colloid transport

A 1.63

A 1.64 Radiation damage Radiolysis of porewater

I 238

E SFR-14

S 067 Radiation effects on buffer/backfill

E SFL-35

J 3.1.13

H 1.2.4 Radioactive gases Gas transport

W 2.055

A 1.66 Radiolysis Radiolysis of porewater

E GEN-30

J 1.2.01

J 3.1.09

K 1.23

K 3.19

M 3.4.01

S 071

E SFL-37

S 072

K 4.08 Radionuclide migration Sorption, Diffusion, Advection, Colloid transport, Gas transport

K 2.20

K 3.16 Radionuclide transport through buffer




K 4.09 Radionuclide retardation Precipitation and co-precipitation, Sorption, Diffusion

K 3.10


Sorption

K 7.09



E SFL-50 Radionuclides release and trans-port from the buffer and backfill

Sorption, Diffusion, Advection, Colloid transport, Gas transport, Aqueous solubility and speciation

J 3.1.11 Redox front NA Not a specific FEP within the component BUFFER. Relates to the component GEO-SPHERE.

S 074

E SFL-38

72




Explanatory note

W 2.065

J 1.2.08 Redox potential Porewater composition

W 2.066 Reduction-oxidation kinetics Porewater composition

J 5.14 Resaturation Water uptake and swelling

S 079 Resaturation of bentonite buffer Water uptake and swelling

A 2.58 Saturation of sorption sites Sorption

J 3.1.02

J 3.1.06 Sedimentation of bentonite Chemical erosion, Piping and ero-sion

S 082

E SFL-43


M 1.6.06 Solubility limit Aqueous solubility and speciation

K 5.16 Solubility limits/colloid formation Aqueous solubility and speciation, Colloid transport, Chemical erosion

K 6.16

W 2.077 Solute transport Diffusion, Advection


A 2.62

J 4.1.04

K 5.09

K 6.09

M 1.6.07

S 084


A 1.74

I 233 Source term & solubility limits Radionuclide inventory, Aqueous solubility and speciation


A 2.64

K 0.2

W 2.056

W 2.082 Suspensions of particles Chemical erosion, Piping and ero-sion

W 1.060 Temperature Temperature

A 1.81 Temperature effects Temperature, Heat transfer

E SFL-46 Temperature of the near-field Temperature, Heat transfer

E SFR-17

S 089 Temperature, bentonite buffer Temperature

73




Explanatory note

I 300 Termperature effects (on trans-port)

NA Not a specific FEP within the component BUFFER. Dealt with in the component GEO-SPHERE

J 4.2.04 Thermal buoyancy NA Not a specific FEP within the component BUFFER. Dealt with in the component GEO-SPHERE.

S 094 Thermal degradation of buffer/backfill


E SFL-47

W 2.029 Thermal effects on material prop-erties


J 3.2.05 Thermal effects on the buffer material


Porewater composition, Microbial activity


All BUFFER FEPs related to migra-tion

K 3.02 Thermal evolution Temperature, Heat transfer

J 4.1.07 Thermo-chemical effects Montmorillonite transformation, Alteration of accessory minerals

H 1.2.8

J 4.2.07 Thermo-hydro-mechanical effects Heat transfer, Water uptake and swelling

S 096 Transport and release of nu-clides, bentonite buffer




All BUFFER FEPs related to migra-tion


J 3.2.01.2 Uneven swelling of bentonite Water uptake and swelling

H 1.5.3 Unsaturated flow due to gas production

Gas transport

I 317 Unsaturated transport All BUFFER FEPs related to migra-tion

A 1.88

S 101 Water chemistry, bentonite buffer Porewater composition, Buffer composition

K 4.07 Water flow at the bentonite-host rock interface

NA Not a specific FEP within the component BUFFER, but treated in interaction matrices

I 039 Vault chemical interactions NA Not a specific FEP within the component BUFFER, but treated in interaction matrices

74

Table B-4. Component-wise mapping of TURVA-2012 BACKFILL FEPs to NEA FEPs (*NEA Version 2.1 Project Databases) screened “IN”. Checked by Heini Laine & Nu-ria Marcos.


NEA FEP names after initial aggregation (BACKFILL)

BACKFILL FEP name (TURVA-2012)

Explanatory note



M 1.6.01

E GEN-02 Anion exclusion Sorption, Diffusion Anions do not sorb in clays (mostly)

S 002

I 011a Backfill (properties) Tunnel backfill, Swelling pressure, Backfill composition, Porewater composition, Gas composition, Temperature

A 1.01

W 2.010

W 2.009

J 2.1.09 Backfill effects on Cu corrosion NA Not a specific FEP within the component BACKFILL, but treated in interaction matrix

A 1.02 Backfill evolution All BACKFILL related FEPs

J 3.2.11 Backfill material deficiencies Water uptake and swelling, Piping and erosion, Chemical erosion, Backfill composition, backfill ge-ometry

K 3.13 Bentonite cementation Montmorillonite transformation, Alteration of accessory minerals

K 3.06 Bentonite erosion Piping and erosion, Chemical ero-sion

K 3.05 Bentonite plasticity Swelling pressure This is a property or feature

K 3.09 Bentonite porewater chemistry Porewater composition

K 3.03 Bentonite saturation Water uptake and swelling

K 3.04 Bentonite swelling pressure Water uptake and swelling

A 1.80

I 298



I 012

I 027 Piping Piping and erosion

I 048 Cement-clay interaction Montmorillonite transformation, Alteration of accessory minerals

K 3.25

K 3.14 Fe-clay interaction Montmorillonite transformation, Alteration of accessory minerals

A 2.06 Cavitation Piping and erosion

W 2.063 Changes in sorptive surfaces Sorption

S 006 Chemical alteration of the buffer Montmorillonite transformation,

75




Explanatory note

E SFL-03 and backfill Alteration of accessory minerals

W 2.075 Chemical degradation of backfill Montmorillonite transformation, Alteration of accessory minerals

W 2.051 Chemical effects of corrosion Montmorillonite transformation, Alteration of accessory minerals

J 4.2.10 Chemical effects of rock rein-forcement


N 1.6.14 Chemical gradients Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Diffusion, Montmorillonite transformation, Alteration of acces-sory minerals

A 1.09

W 2.097

M 1.6.14

A 1.10 Chemical interactions Porewater composition, Backfill composition

A 1.11 Chemical kinetics Porewater composition, Backfill composition, sorption, Precipitation and co-precipitation, Diffusion, Aqueous solubility and speciation

E SFL-04 Coagulation of bentonite Porewater composition

J 3.1.05

S 007

E SFL-05 Colloid behaviour in the buffer and backfill

Colloid transport

W 2.080 Colloid filtration Colloid transport

E SFR-10


A 2.08

I 058

W 2.079

N 1.6.9

J 3.1.04


S 008

J 5.45

S 009 Colloid generation-source Colloid transport



A 1.13

A 3.026

J 4.1.03 Colloids, complexing agents Colloid transport, Aqueous solubility and speciation

A 2.09 Complexation by organics Aqueous solubility and speciation, Backfill, Backfill composition

A 1.14

76




Explanatory note

N 1.6.10 Complexing agents Porewater composition

J 4.1.09

W 2.043 Convection Heat transfer

A 1.22

A 2.11

J 2.1.08 Corrosive agents, Sulphides, oxygen etc

Backfill composition

M 1.2.14 Decrease of plasticity of the clay Montmorillonite transformation, Alteration of accessory minerals

W 2.044 Degradation of organic material Backfill composition

J 3.1.01 Degradation of the bentonite by chemical reactions



A 2.16

E GEN-09

M 1.6.02

S 023

W 2.091

J 3.2.06

S 024

E SFL-15

E SFR-09

S 025 Dilution of buffer/backfill Chemical erosion

E SFL-16

A 1.28 Dispersion Chemical erosion, Piping and ero-sion

A 2.18

A 3.042

J 6.04

S 026

K 4.04 Effect of bentonite swelling on EDZ



Microbial activity


Microbial activity


Microbial activity

J 3.1.03 Effects of bentonite on groundwa-ter chemistry

NA Not a FEP in itself but taken into account in coupling with other components and inter-action matrices

W 1.038 Effects of dissolution Chemical erosion

77




Explanatory note


K 1.15

K 3.18


J 3.2.04 Erosion of buffer/backfill Piping and erosion, Chemical ero-sion

S 031

E SFL-17

E SFL-54 Evolving water chemistry in the backfill

Porewater composition

J 4.2.02.1 Excavation/backfilling effects on nearby rock


J 3.2.09 Flow through buffer/backfill Piping and erosion, Advection

S 037

A 1.34 Formation of cracks Water uptake and swelling

A 1.35 Formation of gases NA Not a specific FEP within the component BACKFILL. Dealt with in e.g. the component CANISTER



S 041 Gas flow through the buffer and backfill

E SFL-24

J 3.2.12


K 3.15 Gas permeability


K 6.17


J 6.02



K 5.04 Groundwater flow path NA Not a specific FEP within the component BACKFILL. Dealt with in the component GEO-SPHERE

A 1.40 Hydraulic conductivity Water uptake and swelling

J 4.2.02.2 Hydraulic conductivity change - Excavation/backfilling effect


A 2.35 Hydraulic properties - evolution NA Not a specific FEP within the component BACKFILL. Dealt with in the component GEO-SPHERE.

E SFL-42 Hydraulic resaturation of the buffer and backfill


78




Explanatory note



A 1.43 Hydrothermal alteration Montmorillonite transformation, Alteration of accessory minerals

M 3.1.05 Induced chemical changes Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption, Montmorillonite transfor-mation, Alteration of accessory minerals

K 3.21 Inhomogeneities (properties and evolution)

Backfill composition, Backfill ge-ometry

S 051 Interaction with corrosion prod-ucts


M 3.2.02 Interactions of host materials and ground water with repository materials

Chemical erosion, Montmorillonite transformation, Alteration of acces-sory minerals

N 3.2.3

J 3.1.10 Interactions with corrosion prod-ucts and waste


W 2.060 Kinetics of precipitation and dissolution




W 2.067 Localized reducing zones NA Not a specific FEP within the component BACKFILL. Dealt with in the component GEO-SPHERE in Site Description.

A 1.51 Long-term physical stability Piping and erosion, Chemical ero-sion, Freezing and thawing

A 1.52 Long-term transients All BACKFILL related FEPs

M 1.6.13 Mass, isotopic and species dilu-tion

NA Not a specific FEP within the component BACKFILL

M 3.4.02 Material propertiy changes NA Not a specific FEP within the component BACKFILL. Dealt with in the component FUEL and related to aqueous solu-bility and speciation in all components.

J 4.2.02.3 Mechanical effects - Excava-tion/backfilling effects

Water uptake and swelling, Piping and erosion

W 2.035 Mechanical effects of backfill Water uptake and swelling




NA Not a specific FEP within the component BACKFILL. Re-lated to the component GEOSPHERE. Dealt with in Site Description.


A 1.54

J 2.1.10

W 1.071

K 5.22

79




Explanatory note

K 6.22

K 1.22

K 3.17

S 057

E SFL-32

M 3.2.07

N 3.2.7

A 1.55

W 2.087 Microbial transport Microbial activity, Colloid transport

K 3.12b Mineralogical alteration - long term


K 3.12a Mineralogical alteration - short term



K 6.10


W 2.069 Organic ligands Aqueous solubility and speciation, sorption

K 5.21 Organics Backfill composition

K 6.21

J 4.1.02 pH-deviations Porewater composition


A 1.62 Precipitation and dissolution Precipitation and co-precipitation, Aqueous solubility and speciation

A 2.49

S 060

J 3.2.08 Preferential pathways in the buffer/backfill

Piping and erosion, Advection

S 066 Properties of tunnel backfill Temperature, Swelling pressure, Backfill geometry, Water content, Backfill composition, Porewater composition, Gas composition


A 1.63

A 1.64 Radiation damage NA Not a specific FEP within the component BACKFILL. Dealt with in the component BUFFER.

I 238

E SFR-14


W 2.055

K 4.08 Radionuclide migration Sorption, Diffusion, Advection, Colloid transport, Gas transport, Aqueous solubility and speciation

K 2.20

80




Explanatory note

E SFL-50 Radionuclides release and trans-port from the buffer and backfill




K 4.09 Radionuclide retardation Precipitation and co-precipitation, Sorption, Diffusion

K 3.10


Sorption

K 7.09



J 3.1.11 Redox front NA Not a specific FEP within the component BACKFILL. Re-lates to the component GEO-SPHERE.

S 074

E SFL-38

W 2.065

J 1.2.08 Redox potential Porewater composition

W 2.066 Reduction-oxidation kinetics Porewater composition

J 5.14 Resaturation Water uptake and swelling

S 080 Resaturation of tunnel backfill Water uptake and swelling


J 3.1.02

J 3.1.06 Sedimentation of bentonite Piping and erosion, Chemical ero-sion

S 082

E SFL-43



K 5.16 Solubility limits/colloid formation Aqueous solubility and speciation, Colloid transport

K 6.16

W 2.077 Solute transport Diffusion, Advection


A 2.62

J 4.1.04

K 5.09

K 6.09

M 1.6.07

S 084


A 1.74

81




Explanatory note



A 2.64

K 0.2

W 2.056

J 5.24 Stress changes of conductivity Water uptake and swelling

W 2.082 Suspensions of particles Chemical erosion, Piping and ero-sion

E SFL-45 Swelling of the tunnel backfill Water uptake and swelling

S 088


A 1.81 Temperature effects Temperature, Heat transfer

E SFL-46 Temperature of the near-field Temperature, Heat transfer

E SFR-17

S 093 Temperature, tunnel backfill Temperature

I 300 Termperature effects (on trans-port)

NA Not a specific FEP within the component BACKFILL – nonetheless considered in groundwater flow models (e.g. EPM)

J 4.2.04 Thermal buoyancy NA Not a specific FEP within the component BACKFILL

S 094 Thermal degradation of buffer/backfill


E SFL-47

W 2.029 Thermal effects on material prop-erties



Porewater composition, Microbial activity


Diffusion


J 4.1.07 Thermo-chemical effects Montmorillonite transformation, Alteration of accessory minerals

H 1.2.8

J 4.2.07 Thermo-hydro-mechanical effects Heat transfer, Water uptake and swelling

S 099 Transport and release of nu-clides, tunnel backfill




Sorption, diffusion, Advection, Colloid transport, Gas transport


J 3.2.01.2 Uneven swelling of bentonite Water uptake and swelling

82




Explanatory note

H 1.5.3 Unsaturated flow due to gas production

Gas transport

I 317 Unsaturated transport Sorption, Diffusion, Advection, Colloid transport, Gas transport

A 1.88

S 104 Water chemistry, tunnel backfill Porewater composition, Backfill composition

K 4.07 Water flow at the bentonite-host rock interface

NA Not a specific FEP within the component BACKFILL, but treated in interaction matrices

I 039 Vault chemical interactions NA Not a specific FEP within the component BACKFILL, but treated in interaction matrices

83

Table B-5. Component-wise mapping of TURVA-2012 AUXILIARY COMPONENT FEPs to NEA FEPs (*NEA Version 2.1 Project Databases) screened “IN”. Checked by Heini Laine & Nuria Marcos.


NEA FEP names after initial aggregation (AUXILIARY COMPONENTS)

AUXILIARY COMPONENTS FEP name (TURVA-2012)

Explanatory note

W 2.090 Advection and dispersion Transport through auxiliary com-ponents

M 1.6.01

E GEN-02 Anion exclusion Transport through auxiliary com-ponents

For clay components similar processes are expected as for the buffer and backfill S 002

W 2.088 Biofilms Chemical degradation


I 012

A 2.04 Borehole seal failure Chemical degradation, Physical degradation, Freezing and thaw-ing

I 048 Cement-clay interaction Chemical degradation

K 3.25

K 3.14 Fe-clay interaction Chemical degradation

A 2.06 Cavitation Physical degradation See Piping and erosion for BUFFER and BACKFILL

W 2.063 Changes in sorptive surfaces Transport through auxiliary com-ponents

W 2.074 Chemical degradation of seals Chemical degradation

W 2.051 Chemical effects of corrosion Chemical degradation

J 4.2.10 Chemical effects of rock reinforce-ment

Chemical degradation

N 1.6.14 Chemical gradients Chemical degradation

A 1.09

W 2.097

M 1.6.14

A 1.10 Chemical interactions Chemical degradation

A 1.11 Chemical kinetics Chemical degradation

K 1.21 Colloid formation Transport through auxiliary com-ponents

A 2.08

I 058

W 2.079

N 1.6.9

J 3.1.04

W 2.078 Colloid transport Transport through auxiliary com-ponents

S 008

J 5.45

84




Explanatory note

W 2.081 Colloid sorption Transport through auxiliary com-ponents

K 4.12 Colloids Groundwater composition

A 1.13

A 3.026

J 4.1.03 Colloids, complexing agents Groundwater composition

A 2.09 Complexation by organics Transport through auxiliary com-ponents

A 1.14

N 1.6.10 Complexing agents Groundwater composition

J 4.1.09

A 1.15 Concrete Material composition

I 062d Concrete (degradationÐnatural, artificial)

Chemical degradation, Physical degradation, Freezing and thaw-ing

I 062e Concrete (rebar corrosion) Chemical degradation

W 2.073 Concrete hydration Physical degradation

W 2.043 Convection Transport through auxiliary com-ponents

A 1.22

A 2.11



S 020 Degradation of hole and shaft seals Chemical degradation, Physical degradation, Freezing and thaw-ing

J 5.11

W 2.044 Degradation of organic material Material composition

S 021 Degradation of rock reinforcement and grout


E GEN-08

E GEN-07 Degradation of the borehole and shaft seals


A 1.27 Diffusion Chemical degradation, Transport through auxiliary components

A 2.16

E GEN-09

M 1.6.02

S 023

W 2.091

J 3.2.06

S 024

E SFL-15

E SFR-09

A 1.28 Dispersion Chemical degradation, Transport Implicitly in interaction matri-

85




Explanatory note

A 2.18 through auxiliary components ces e.g. with GEOSPHERE.

A 3.042

J 6.04

S 026



W 2.064 Effect of metal corrosion Chemical degradation


NA Not a specific FEP within AUXILIARY COMPONENTS. Implicitly dealt with in micro-bial activity.


Temperature, Material composi-tion

W 1.038 Effects of dissolution Groundwater composition

W 2.100 Enhanced diffusion Transport through auxiliary com-ponents

W 2.072 Exothermic reactions Chemical degradation, Tempera-ture

K 5.25 Exploratory boreholes (sealing) Chemical degradation, Physical degradation, Freezing and thaw-ing

E GEN-35 Fast transport pathways Transport through auxiliary com-ponents

Main treatment in interaction matrices with other compo-nents

A 1.34 Formation of cracks Physical degradation

A 1.35 Formation of gases Chemical degradation, Material composition


M 3.3.06 Gas effects Transport through auxiliary com-ponents

J 1.2.04 Gas generation

I 015 Gas generation (CH4, CO2, H2)

E SFR-11 Gas generation in the repository



K 6.17


J 6.02



A 1.40 Hydraulic conductivity Transport through auxiliary com-ponents

A 2.35 Hydraulic properties - evolution All AUXILIARY COMPONENT related FEPs


Repository geometry, material composition

86




Explanatory note

H 1.2.1 Hydrogen by metal corrosion Chemical degradation

K 2.16 Hydrogen production NA Not a specific FEP for AUX-ILIARY COMPONENTS. Dealt with in the component CANISTER.

A 1.43 Hydrothermal alteration Chemical degradation

M 3.1.05 Induced chemical changes Chemical degradation, Transport through auxiliary components

S 051 Interaction with corrosion products Chemical degradation


NA Not a specific FEP for AUX-ILIARY COMPONENTS, but treated in interaction matrices N 3.2.3



W 2.038 Investigation boreholes Repository geometry

M 2.1.02 Investigation borehole seal failure and degradation




W 2.062 Kinetics of sorption Transport through auxiliary com-ponents

W 2.057 Kinetics of speciation Material composition, Transport through auxiliary components

W 2.067 Localized reducing zones NA Not a specific FEP for AUXIL-IARY COMPONENTS. Dealt with in the component GEO-SPHERE.

A 1.51 Long-term physical stability Physical degradation

A 1.52 Long-term transients All AUXILIARY COMPONENT related FEPs

H 5.1.1 Loss of integrity of borehole seals Chemical degradation, Physical degradation, Freezing and thaw-ing

H 5.1.2 Loss of integrity of shaft or access tunnel seals


M 1.6.13 Mass, isotopic and species dilution Groundwater composition

M 3.4.02 Material propertiy changes NA No radiation effects are ac-counted for AUXILIARY COMPONENTS

W 2.037 Mechanical degradation of seals Physical degradation


Physical degradation

A 2.45 Microbial activity Transport through auxiliary com-ponents, Chemical degradation

A 1.54

J 2.1.10

W 1.071

K 5.22

K 6.22

87




Explanatory note

K 1.22

K 3.17

S 057

E SFL-32

M 3.2.07

N 3.2.7

A 1.55

W 2.076 Microbial growth on concrete Chemical degradation

W 2.087 Microbial transport Transport through auxiliary com-ponents

K 5.10 Non-linear sorption Transport through auxiliary com-ponents

K 6.10

W 2.068 Organic complexation Groundwater composition

W 2.069 Organic ligands Groundwater composition, Mate-rial composition

K 5.21 Organics Groundwater composition, mate-rial composition

K 6.21

A 1.59 Percolation in shafts NA Not a specific FEP within AUXILIARY COMPONENTS, but the possibility and conse-quences are dealt with e.g. in FEP Groundwater flow and advective transport

J 4.1.02 pH-deviations Groundwater composition, Chemical degradation

H 1.1.2 Physico-chemical degradation of concrete


W 2.059 Precipitation Chemical degradation

A 1.62 Precipitation and dissolution Chemical degradation

A 2.49

S 060

A 2.50 Pseudo-colloids Groundwater composition

A 1.63

A 1.64 Radiation damage NA

I 238

E SFR-14

H 1.2.4 Radioactive gases Transport through auxiliary com-ponents

W 2.055

K 4.08 Radionuclide migration Transport through auxiliary com-ponents

K 2.20

E GEN-27 Radionuclide precipitation and Transport through auxiliary com-

88




Explanatory note

dissolution ponents

E GEN-31 Radionuclide reconcentration Transport through auxiliary com-ponents

K 4.09 Radionuclide retardation Transport through auxiliary com-ponents

K 3.10


Transport through auxiliary com-ponents

Far field

K 7.09



J 3.1.07 Reactions with cement pore water Chemical degradation

J 3.1.11 Redox front NA Not a specific FEP within AUXILIARY COMPONENTS. Dealt with in the component GEOSPHERE.

S 074

E SFL-38

W 2.065

J 1.2.08 Redox potential Groundwater composition

W 2.066 Reduction-oxidation kinetics Groundwater composition, Mate-rial composition

J 5.14 Resaturation NA

A 2.58 Saturation of sorption sites NA

J 3.1.02

W 2.008 Seal chemical composition Material composition

A 1.71 Seal evolution Chemical degradation, Physical degradation, Freezing and thaw-ing, Transport through auxiliary components

A 1.72 Seal failure Chemical degradation, Physical degradation

W 2.006 Seal geometry Repository geometry

W 2.007 Seal physical properties Material composition

K 4.17 Shaft and tunnel seals Material composition

M 2.1.03 Shaft or access tunnel seal failure and degradation


A 2.60 Shaft seal failure Chemical degradation, Physical degradation, Freezing and thaw-ing

J 5.44 Solubility and precipitation Chemical degradation

M 1.6.06 Solubility limit Transport through auxiliary com-ponents

K 5.16 Solubility limits/colloid formation Transport through auxiliary com-ponents

K 6.16

W 2.077 Solute transport Transport through auxiliary com-ponents

A 1.73 Sorption Transport through auxiliary com-

89




Explanatory note

A 2.62 ponents

J 4.1.04

K 5.09

K 6.09

M 1.6.07

S 084

A 2.63 Sorption - nonlinear Transport through auxiliary com-ponents

A 1.74

I 233 Source term & solubility limits Transport through auxiliary com-ponents

A 1.77 Speciation Groundwater composition

A 2.64

K 0.2

W 2.056

W 2.082 Suspensions of particles Transport through auxiliary com-ponents

Discussed in relation to col-loid transport

J 3.2.07 Swelling of corrosion products Chemical degradation, Physical degradation


A 1.81 Temperature effects Temperature, Transport through auxiliary components, Freezing and thawing

E SFL-46 Temperature of the near-field NA See FEPs Temperature and Transport through auxiliary components E SFR-17

I 300 Temperature effects (on transport) Temperature, Transport through auxiliary components

J 4.2.04 Thermal buoyancy Groundwater composition

M 2.1.10 Thermal effects (e.g. concrete hydration)

Material composition


Material composition


Temperature, Chemical degrada-tion


Temperature, Transport through auxiliary components

K 3.02 Thermal evolution Temperature, Freezing and thaw-ing

J 4.1.07 Thermo-chemical effects Temperature, Chemical degrada-tion, Freezing and thawing

H 1.2.8

J 4.2.07 Thermo-hydro-mechanical effects Temperature, Chemical degrada-tion, Freezing and thawing

A 1.84 Transport in gases or of gases Transport through auxiliary com-ponents



90




Explanatory note

W 2.089 Transport of radioactive gases Transport through auxiliary com-ponents



I 317 Unsaturated transport Transport through auxiliary com-ponents

A 1.88

I 039 Vault chemical interactions NA Not a specific FEP within AUXILIARY COMPONENTS, but the possibility and conse-quences are dealt with in interaction matrices


Chemical degradation, Physical degradation

Table B-6. Component-wise mapping of TURVA-2012 GEOSPHERE FEPs to NEA FEPs (*NEA Version 2.1 Project Databases) screened “IN”. Checked by Pirjo Hellä, Annika Hagros, Lasse Koskinen, Petteri Pitkänen and Margit Snellman.


NEA FEP names after initial aggregation (GEOSPHERE)

GEOSPHERE FEP name (TURVA-2012)

Explanatory note

K 4.16 Access tunnels and shafts Repository geometry


W 2.090 Advection and dispersion Groundwater flow and advective transport

M 1.6.01

E GEN-01 Alteration and weathering along flow paths

Rock-water interaction

S 001

E GEN-02 Anion exclusion Diffusion and matrix diffusion

Sorption

S 002

I 013 Bedrock fracture Fractures and deformation zones


H 4.2.6 Biogeochemical processes Microbial activity

A 1.03 Biological activity Microbial activity

I 012

K 7.05 Boundary conditions for flow Temperature, Groundwater pres-sure, Groundwater flux, Ground-water composition

Repository geometry, Fracture geometry

Handled in interaction matri-ces and linked to surface environment FEP Groundwa-ter discharge and recharge

S 004 Cave in Spalling, Reactivation-displacements along existing fractures

A 1.08

E GEN-03

91




Explanatory note

A 2.06 Cavitation NA Not a specific FEP within the component GEOSPHERE. Dealt with in BUFFER, BACKFILL and AUXILIARY COMPONENTS; see Piping and erosion.

W 1.009 Changes in fracture properties Fracture properties, Reactivation-displacements along existing fractures, Erosion and sedimenta-tion in fractures, Rock-water interaction

Changes are mainly handled in interaction matrices

H 2.2.1 Changes in geometry and driving forces of the flow system

Temperature, Groundwater pres-sure, Groundwater flux, Ground-water composition, Groundwater flow and advective transport

The processes causing the change, such as glaciation, are External FEPs - changes handled in interaction matri-ces

W 1.036 Changes in groundwater Eh Groundwater composition, Rock-water interaction

W 1.037 Changes in groundwater pH Groundwater composition, Rock-water interaction

M 3.3.02 Changes in in-situ stress field Rock stress, Stress redistribution

W 1.003 Changes in regional stress Rock stress, Stress redistribution The processes causing the change such as land uplift and depression are External FEPs - changes handled in interaction matrices

W 2.063 Changes in sorptive surfaces Fracture properties, Rock matrix properties, Sorption


W 2.021 Changes in the stress field Rock stress, Stress redistribution Changes are mainly handled in interaction matrices

J 4.2.10 Chemical effects of rock reinforce-ment

Groundwater composition, Rock-water interaction, Groundwater flow and advective transport


N 1.6.14 Chemical gradients Groundwater composition, Groundwater flow and advective transport

A 1.09

W 2.097

M 1.6.14

A 1.10 Chemical interactions Rock-water interaction, Aqueous solubility and speciation, Sorption

Most interactions are mainly handled in interaction matri-ces

A 1.11 Chemical kinetics Rock-water interaction, Aqueous solubility and speciation, Precipi-tation and co-precipitation

W 1.042 Chemical weathering Rock-water interaction

E GEN-04 Colloid behaviour in the host rock Colloid transport


A 2.08

I 058

W 2.079

N 1.6.9

J 3.1.04

92




Explanatory note


S 008

J 5.45



A 1.13

A 3.026

J 4.1.03 Colloids, complexing agents Groundwater composition, Colloid transport

A 2.09 Complexation by organics Aqueous solubility and speciation

A 1.14

N 1.6.10 Complexing agents Groundwater composition

J 4.1.09

W 2.043 Convection Heat transfer, Groundwater flow and advective transport

A 1.22

A 2.11


Groundwater composition

J 4.2.09 Creeping of rock mass Creep

S 015

E GEN-05

A 2.13 Damaged zone Reactivation-displacements along existing fractures, Spalling

S 018 Deep saline water intrusion Groundwater flow and advective transport

W 2.040

W 2.044 Degradation of organic material Microbial activity

W 1.026 Density effects on groundwater flow Groundwater flow and advective transport

K 5.12

K 7.13

K 6.12

A 1.27 Diffusion Diffusion and matrix diffusion

A 2.16

E GEN-09

M 1.6.02

S 023

W 2.091

J 3.2.06

S 024

93




Explanatory note

E SFL-15

E SFR-09

J 6.05 Dilution Groundwater flow and advective transport

K 5.23

K 6.23

K 7.07

K 8.21

A 2.17 Discharge zones Fractures and deformation zones, Groundwater flow and advective transport

A 1.28 Dispersion Groundwater flow and advective transport

A 2.18

A 3.042

J 6.04

S 026

J 5.25 Dissolution, precipitation and cristallization of fracture fillings

Erosion and sedimentation in fractures, Rock-water interaction

M 1.6.08

W 1.022

M 1.6.11

S 027 Distribution and release of nuclides from the geosphere

Radionuclide inventory, Aqueous solubility and speciation, Precipi-tation and co-precipitation, Sorp-tion, Diffusion and matrix diffu-sion, Groundwater flow and advective transport, Colloid transport, Gas transport

E GEN-11

W 2.018 Disturbed rock zone Fracture geometry, Fracture properties, Stress redistribution, Reactivation-displacements along existing fractures, Spalling, Groundwater flow and advective transport

H 1.5.2

A 1.29 Earthquakes/seismic activity Reactivation-displacements along existing fractures

A 2.21

A 3.045

J 5.15

M 1.2.08

K 9.05

W 1.012

I 100

94




Explanatory note

H 2.1.6


Microbial activity


Temperature, Microbial activity

M 1.5.08 Effects at saline-freshwater inter-face


J 3.1.03 Effects of bentonite on groundwater chemistry

NA Not a specific FEP within the component GEOSPHERE, but treated in interaction matrices

W 1.038 Effects of dissolution Groundwater composition, Rock-water interaction

H 2.1.9 Effects of natural gases. Gas transport

W 1.027 Effects of preferential pathways Fractures properties, Groundwa-ter flow and advective transport


K 1.15

K 3.18

W 2.100 Enhanced diffusion Diffusion and matrix diffusion

J 5.18 Enhanced groundwater flow Groundwater flow and advective transport

E GEN-14 Enhanced rock fracturing Reactivation-displacements along existing fractures, Spalling

J 4.2.08

S 030

E SFL-55 Evolving water chemistry in the near-field rock

Groundwater composition, Groundwater flow and advection, Rock-water interaction

S 032 Excavation effects on the near field rock

Fracture geometry, fracture prop-erties, Reactivation-displacements along existing fractures, Spalling, Groundwater flow and advection

E GEN-15

J 4.2.02.1 Excavation/backfilling effects on nearby rock

Fracture geometry, Fracture properties, Stress redistribution, Reactivation-displacements along existing fractures, Spalling, Groundwater flow and advective transport, Creep

K 4.01 Excavation-disturbed zone (EDZ) Fracture geometry, Fracture properties, Stress redistribution, Reactivation-displacements along existing fractures, Spalling, Groundwater flow and advective transport

W 2.019 Excavation-induced changes in stress

Stress redistribution

K 8.03 Exfiltration to a local aquifer Groundwater flow and advective transport

K 8.04 Exfiltration to surface waters Groundwater flow and advective transport

95




Explanatory note

S 033 External flow boundary conditions Groundwater pressure, Ground-water flux, Groundwater composi-tion


J 2.3.07.1 External stress Rock stress, Stress redistribution

J 4.2.03 Extreme channel flow of oxidants and nuclides

Fracture properties, Groundwater flow and advective transport

J 6.03 Far field hydrochemistry - acids, oxidants, nitrate


I 040 Farfield chemical interactions Groundwater flow and advective transport, Rock-water interaction

E GEN-22 Far-field groundwater chemistry Groundwater composition

H 2.3.1 Far-field transport: Advection Groundwater flow and advective transport

H 2.3.13 Far-field transport: Biogeochemical changes

Microbial activity

H 2.3.7 Far-field transport: Changes in groundwater chemistry and flow direction

Groundwater composition, Groundwater flow and advective transport, Rock-water interaction

H 2.3.6 Far-field transport: Changes in sorptive surfaces

Fracture properties, Rock matrix properties, Sorption

H 2.3.8 Far-field transport: Colloid trans-port

Colloid transport

H 2.3.2 Far-field transport: Diffusion Diffusion and matrix diffusion

H 2.3.3 Far-field transport: Hydrodynamic dispersion

Groundwater flow and advective transport

H 2.3.4 Far-field transport: Solubility con-straints

Aqueous solubility and speciation

H 2.3.5 Far-field transport: Sorption includ-ing ion-exchange

Sorption

H 2.3.12 Far-field transport: Thermal effects on hydrochemistry

Temperature, Aqueous solubility and speciation

H 2.3.10 Far-field transport: Transport of radioactive gases

Gas transport

H 2.3.9 Far-field transport: Transport of radionuclides bound to microbes

Colloid transport

E GEN-35 Fast transport pathways Fracture geometry, Fracture properties, Groundwater flow and advective transport

Degradation of closure com-ponents handled in interac-tion matrices and linked to auxiliary components FEPs Chemical degradation and Physical degradation

M 1.2.09 Faulting/fracturing Reactivation-displacements along existing fractures

M 1.2.10

W 1.011

A 2.24

E GEN-17

S 036

J 4.2.06

96




Explanatory note

H 2.1.7

W 1.008

W 1.010

M 3.3.05

A 1.34 Formation of cracks Spalling

A 1.35 Formation of gases Gas transport

W 1.025 Fracture flow Groundwater flow and advective transport

I 268 Freeze/thaw cycles NA This can be mapped to Per-mafrost, which is an External FEP. Taken into account through the boundary condi-tions.

W 1.035 Freshwater intrusion Groundwater composition, Groundwater flow and advective transport

W 1.030

A 2.26 Fulvic acid Groundwater composition


S 042 Gas flow and transport, near-field rock/far-field

Gas transport

E GEN-18 Gas flow in the far-field Gas transport

E SFR-12 Gas flow in the near-field Gas transport

J 1.2.04 Gas generation Gas composition, Gas transport

I 015 Gas generation (CH4, CO2, H2) Gas composition, Gas transport

S 043 Gas generation in the far-field Gas composition, Gas transport

E GEN-19

M 1.6.04 Gas mediated transport Gas transport

K 5.17 Gas pressure effects Groundwater pressure

K 6.17

H 1.2.6 Gas transport Gas transport

J 6.02

K 4.11 Gas transport/dissolution Gas transport

K 0.3 Gaseous and volatile isotopes Gas transport

A 2.27 Gases and gas transport Gas transport

A 2.29 Geochemical interactions Rock-water interaction

A 2.28 Geothermal gradient effects Heat transfer, Groundwater flow and advective transport

97




Explanatory note

K 5.13 Geothermal regime Temperature, Heat transfer

K 6.13

J 6.13 Geothermally induced flow Heat transfer, Groundwater flow and advective transport

M 1.5.06 Ground water conditions Groundwater pressure, Ground-water flux, Groundwater composi-tion, Groundwater flow and ad-vective transport

M 1.5.04 Groundwater discharge Groundwater flow and advective transport


N 1.5.4

W 1.053

A 2.33 Groundwater - evolution Groundwater composition, Groundwater flow and advective transport, Rock-water interaction

Handled also in interaction matrices

I 143 Groundwater (redirection of) Groundwater flow and advective transport

K 4.06 Groundwater chemistry Groundwater composition

K 5.08

K 6.08

K 7.08

S 048

A 2.32

N 1.5.6

W 1.033

E SFR-20 Groundwater chemistry in the near-field


E SFR-23

J 4.1.08

H 4.1.1 Groundwater discharge to soils and surface waters


Handled by interaction matrix and linked to surface envi-ronment FEP Groundwater discharge and recharge

M 1.5.05 Groundwater flow Groundwater flow and advective transport

E GEN-23

H 2.2.3

K 7.04

S 049

J 4.2.05

K 5.04 Groundwater flow path Fracture geometry, fracture prop-

98




Explanatory note

K 6.04 erties, Groundwater flow and advective transport

K 7.06

E SFL-20

E SFR-21 Groundwater movement in the near-field


W 1.054 Groundwater recharge/discharge Groundwater flow and advective transport

Handled also in interaction matrices

J 5.46

A 1.67

A 2.53

M 1.5.03

W 1.056

E GEN-06 Groundwater salinity changes Groundwater composition, Salt exclusion, Groundwater flow and advective transport

K S1.3 Host Geology Geosphere

M 3.1.03 Host rock fracture aperture changes Fracture properties, Fracture Geometry, Reactivation-displacements along existing fractures, Erosion and sedimenta-tion in fractures, Rock-water interaction

A 2.34 Humic and fulvic acids Groundwater composition

W 2.070

A 1.40 Hydraulic conductivity Rock matrix properties, Fracture properties

J 4.2.02.2 Hydraulic conductivity change - Excavation/backfilling effect

Fracture properties, Fracture Geometry, Reactivation-displacements along existing fractures, Erosion and sedimenta-tion in fractures, Rock-water interaction, Groundwater flow and advective transport

K 7.12 Hydraulic gradient (magnitude, regional direction)

Groundwater pressure Linked to External FEPs such as Land uplift and depression

K 5.18 Hydraulic gradient changes (magni-tude, direction)

Groundwater pressure Linked to External FEPs such as Land uplift and depression

K 6.18

A 1.41 Hydraulic head Groundwater pressure Linked to Surface Environ-ment FEP Groundwater recharge and discharge

A 2.35 Hydraulic properties - evolution Groundwater pressure, Ground-water flux, Rock matrix proper-ties, Fracture properties, Groundwater flow and advective transport

W 1.031 Hydrological response to earth-quakes

Fracture properties, Reactivation-displacements along existing fractures, Groundwater flow and

99




Explanatory note

advection

M 3.1.05 Induced chemical changes Groundwater composition, Groundwater flow and advective transport, Rock-water interaction

M 3.1.04 Induced hydrological changes Groundwater flow and advective transport

N 3.1.4

W 1.055 Infiltration Groundwater pressure, Ground-water composition, Groundwater flow and advective transport

Handled in interaction matri-ces

K 5.19 Influx of oxidising water Groundwater pressure, Ground-water composition, Groundwater flow and advective transport

K 6.19


Groundwater composition Handled in interaction matri-ces

N 3.2.3

S 052 Interfaces between different waters Groundwater composition

E GEN-24

K 8.28 Interface effects Groundwater composition Handled in interaction matri-ces

K 5.11 Intrusion of saline groundwater Groundwater composition, Groundwater flow and advective transport

K 6.11

W 1.034

W 1.029

A 2.38 Isostatic rebound Stress redistribution Linked to External FEP Land uplift and depression


Rock-water interactions, Aqueous solubility and speciation, Precipi-tation and co-precipitation



A 1.52 Long-term transients All GEOSPHERE related FEPs Dealt with in interaction ma-trices

M 3.4.02 Material property changes NA Radiation damage not signifi-cant in crystalline rock. Other property changes discussed under other FEPs.

A 2.41 Matrix diffusion Diffusion and matrix diffusion

E GEN-25

J 4.1.05

K 5.06

K 6.06

M 1.6.03

100




Explanatory note

S 054

W 2.092

J 4.2.02.3 Mechanical effects - Excava-tion/backfilling effects

Fracture geometry, Fracture properties, Stress redistribution, Reactivation-displacements along existing fractures, Spalling, Groundwater flow and advective transport

J 4.2.01 Mechanical failure of repository Reactivation-displacements along existing fractures

A 2.44 Methane Groundwater composition, Meth-ane hydrate formation, Microbial activity


Microbial activity

J 5.43 Methane intrusion Methane hydrate formation


A 1.54

J 2.1.10

W 1.071

K 5.22

K 6.22

K 1.22

K 3.17

S 057

E SFL-32

M 3.2.07

N 3.2.7

A 1.55

W 2.087 Microbial transport Microbial activity

K 5.07 Mineralogy Fracture properties, Rock matrix properties

K 6.07

K 9.04 Movements along small-scale faults Reactivation-displacements along existing fractures

M 1.5.09 Natural thermal effects Temperature, Heat transfer


K 6.10

M 3.2.04 Non-radioactive solute plume in geophere

Groundwater composition, Groundwater flow and advective

101




Explanatory note

transport


W 2.069 Organic ligands Groundwater composition

K 5.21 Organics Groundwater composition

K 6.21

J 4.1.01 Oxidizing conditions Groundwater composition

J 4.1.02 pH-deviations Groundwater composition

W 1.039 Physiography Geosphere

W 2.059 Precipitation Rock-water interaction, Precipita-tion and co-precipitation

A 1.62 Precipitation and dissolution Rock-water interaction, Aqueous solubility and speciation, Precipi-tation and co-precipitation

A 2.49

S 060

S 064 Properties of far-field rock Temperature, Groundwater pres-sure, Groundwater flux, Rock stress, Fracture geometry, Rock matrix properties, Fracture prop-erties, Groundwater composition, Gas composition

S 065 Properties of near-field rock Temperature, Groundwater pres-sure, Groundwater flux, Rock stress, Fracture geometry, Rock matrix properties, Fracture prop-erties, Groundwater composition, Gas composition


A 1.63


W 2.055

E GEN-10 Radionuclide dispersion Groundwater flow and advective transport

K 4.08 Radionuclide migration Groundwater flow and advective transport, Diffusion and matrix diffusion

K 2.20



E GEN-31 Radionuclide reconcentration Precipitation and co-precipitation, Sorption

K 4.13 Radionuclide release from EDZ Radionuclide inventory, Ground-water flow and advective trans-port

K 4.09 Radionuclide retardation Sorption, Diffusion and matrix diffusion

K 3.10

102




Explanatory note


Sorption

K 7.09



J 4.1.06 Reconcentration Precipitation and co-precipitation, Sorption

S 073

J 3.1.11 Redox front Groundwater composition, Groundwater flow and advective transport, Rock-water interaction

S 074

E SFL-38

W 2.065

J 1.2.08 Redox potential Groundwater composition, Groundwater flow and advective transport, Rock-water interaction

W 2.066 Reduction-oxidation kinetics Groundwater composition, Rock-water interaction, Aqueous solu-bility and speciation, Precipitation and co-precipitation

K 5.14 Regional stress regime Rock stress

K 6.14

M 1.2.11 Rock heterogeneity Fractures and deformation zones, Fracture geometry, Rock matrix properties, Fracture properties

Geosphere in general

A 2.54 Rock properties Temperature, Fracture geometry, Rock matrix properties, Fracture properties

Geosphere in general

H 2.2.2 Rock property changes Temperature, Fracture geometry, Rock matrix properties, Fracture properties

J 5.01 Saline (or fresh) groundwater intru-sion

Groundwater composition, Groundwater flow and advective transport

M 1.5.07 Saline or freshwater intrusion Groundwater composition, Groundwater flow and advective transport

A 2.57 Salinity effects on flow Groundwater flow and advective transport

W 1.023 Saturated groundwater flow Groundwater flow and advective transport

H 1.5.4


J 3.1.02



K 5.16 Solubility limits/colloid formation Aqueous solubility and speciation,

103




Explanatory note

K 6.16 Colloid transport

W 2.077 Solute transport Groundwater flow and advective transport, Diffusion and matrix diffusion


A 2.62

J 4.1.04

K 5.09

K 6.09

M 1.6.07

S 084


A 1.74



A 2.64

K 0.2

W 2.056

A 1.78 Stability Stress redistribution, Reactiva-tion-displacements along existing fractures, Spalling, Creep

K 9.06 Stress changes - hydrogeological effects

Fracture properties, Groundwater flow and advective transport

J 5.24 Stress changes of conductivity Fracture properties, Groundwater flow and advective transport

E GEN-36 Stress field Rock stress

S 086

M 2.1.04 Stress field changes, setting, subsi-dence or caving

Rock stress, Stress redistribution, Reactivation-displacements along existing fractures, Spalling, Creep

K 7.10 Stress regime Rock stress

W 2.082 Suspensions of particles Erosion and sedimentation in fractures


A 1.81 Temperature effects Temperature, Heat transfer, groundwater flow and advective transport

E GEN-38 Temperature of the far-field Temperature

S 091 Temperature

E SFL-46 Temperature of the near-field Temperature

104




Explanatory note

E SFR-17 Temperature

S 092 Temperature, near-field rock Temperature

I 300 Temperature effects (on transport) Temperature, Groundwater flow and advective transport, Diffusion and matrix diffusion

J 4.2.04 Thermal buoyancy Heat transfer, Groundwater flow and advective transport

W 1.028 Thermal effects on groundwater flow

Heat transfer, Groundwater flow and advective transport

H 1.6.2


Fracture geometry, Fracture properties, Rock matrix proper-ties, Reactivation-displacements along existing fractures, Spalling


Groundwater composition, Micro-bial activity

H 1.6.1 Thermal effects: Rock-mass changes

Fracture geometry, Fracture properties, Reactivation-displacements along existing fractures, spalling


Diffusion and matrix diffusion


W 2.030 Thermally-induced stress changes Rock stress, Stress redistribution

J 4.1.07 Thermo-chemical effects Temperature, Groundwater com-position, Rock-water interactions, Aqueous solubility and speciation, Precipitation and co-precipitation, Sorption

H 1.2.8

J 4.2.07 Thermo-hydro-mechanical effects Temperature, Rock stress, Frac-ture geometry, Rock matrix prop-erties, Fracture properties, Heat transfer, Stress redistribution, Reactivation-displacements of existing fractures, Spalling, Groundwater flow and advective transport

S 098 Transport and release of nuclides, near-field rock

Radionuclide inventory, Ground-water flow and advective trans-port, Diffusion and matrix diffu-sion



Groundwater composition, Groundwater flow and advective transport



Gas transport

E GEN-39 Uplift and subsidence NA Not a specific FEP within the component GEOSPHERE, but treated in interaction matrices

J 5.16

M 1.2.06

S 103 Water chemistry in near-field rock Groundwater composition

K 4.07 Water flow at the bentonite-host Groundwater flow and advective

105




Explanatory note

rock interface transport

K 5.02 Water-conducting features (types) Fracture geometry, Fracture properties

K 6.02

I 091 Water table changes Groundwater pressure Linked to Surface environ-ment FEP Groundwater discharge and recharge and external FEPs e.g. glaciation

I 039 Vault chemical interactions NA Not a specific FEP within the component GEOSPHERE, but treated in interaction matrices

J 6.06 Weathering of flow paths Erosion and sedimentation in fractures, Rock-water interaction

106

Table B-7. Component-wise mapping of TURVA-2012 EXTERNAL FEPs to NEA FEPs (*NEA Version 2.1 Project Databases) screened “IN”. Checked by Thomas Hjerpe & Nuria Marcos.


NEA FEP names after initial aggregation (EXTERNAL)

EXTERNAL FEP name (TURVA-2012)

Explanatory note

M 2.4.09 Anthropogenic climate changes (greenhouse effect)

Climate evolution

H 5.2.4 Human Intrusion (inadvertent) Inadvertent human intrusion

W 2.085

W 2.084

K 11.01

M 2.3.03

N 2.3.3

A 2.05

M 2.3.04

A 1.49

I 169

A 3.071

W 3.019 Explosions for resource recovery NA Future human actions (FHA) to be dealt with in a future safety case

W 3.021 Drilling fluid flow Inadvertent human intrusion

W 3.021 Drilling fluid flow Future human action other than intrusion (see next column)

Future human actions (FHA) to be dealt with in a future safety case

W 3.022 Drilling fluid loss Inadvertent human intrusion

W 3.022 Drilling fluid loss NA Future human actions (FHA) to be dealt with in a future safety case

W 3.024 Drilling-induced geochemical changes

Inadvertent human intrusion

W 3.036

W 3.024 Drilling-induced geochemical changes

NA Future human actions (FHA) to be dealt with in a future safety case W 3.036

W 3.030 Fluid injection-induced geochemical changes

NA Future human actions (FHA) to be dealt with in a future safety case

J 5.21 Future boreholes and undetected past boreholes


J 5.21 Future boreholes and undetected past boreholes

NA Future human actions (FHA) to be dealt with in a future safety case

W 3.007 Geothermal energy production NA Future human actions (FHA) to be dealt with in a future safety case – relates anyhow to Inadvertent human intrusion

M 2.3.05

N 2.3.5

J 5.34

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Explanatory note

K 11.03

W 3.007 Geothermal energy production Inadvertent human intrusion

M 2.3.05

N 2.3.5

J 5.34

K 11.03

W 3.031 Natural borehole fluid flow Future human action other than intrusion

W 3.031 Natural borehole fluid flow Inadvertent human intrusion

M 2.3.10 Liquid waste disposal Future human action other than intrusion

W 3.010

W 3.027

K 11.04

M 2.3.10 Liquid waste disposal Inadvertent human intrusion

W 3.010

W 3.027

K 11.04

J 5.12 Near storage of other waste Future human action other than intrusion

J 5.36 Reuse of boreholes Future human action other than intrusion

J 5.36 Reuse of boreholes Inadvertent human intrusion

W 2.086 Spallings Inadvertent human intrusion

W 3.032 Waste-induced borehole flow Future human action other than intrusion

W 3.032 Waste-induced borehole flow Inadvertent human intrusion

A 3.061 Heat storage in lakes or under-ground

Future human action other than intrusion

A 3.061 Heat storage in lakes or under-ground


W 3.011 Hydrocarbon storage Future human action other than intrusion

W 3.029

W 3.011 Hydrocarbon storage Inadvertent human intrusion

W 3.029

A 2.03 Groundwater exctraction Future human action other than intrusion

Taken into account within several FEPs in the Surface environment W 3.003

M 2.3.11

W 3.005

W 3.026

K 11.05

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Explanatory note

K 8.07

A 2.73

A 2.74

J 5.41

A 2.03 Groundwater exctraction Inadvertent human intrusion Taken into account within several FEPs in the Surface environment W 3.003

M 2.3.11

W 3.005

W 3.026

K 11.05

K 8.07

A 2.73

A 2.74

J 5.41

W 3.043 Reservoirs Future human action other than intrusion

J 5.31 Change in sealevel Climate evolution, Land uplift and depression

A 3.023 Climate Climate evolution

A 2.07 Climate change Climate evolution

A 3.024

I 049

W 1.061

A 1.12

H 3.1.1

H 3.1.2

K 10.04

K 10.06

J 6.08

K 11.09

W 3.049 Damage to the ozone layer Climate evolution

A 1.29 Earthquakes/seismic activity NA The consequences of Earthquakes/seismic activ-ity is taken into account in the Geosphere FEP Reac-tivation-displacements of existing fractures

A 2.21

A 3.045

J 5.15

M 1.2.08

K 9.05

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Explanatory note

W 1.012

I 100

H 2.1.6

H 3.1.3 Exit from glacial/interglacial cycling Climate evolution

M 1.3.02 Extremes of precipitation, snow melt, and associated

Climate evolution

W 1.035 Freshwater intrusion Glaciation

W 1.030

K 10.14 Glacial erosion/sedimentation Glaciation

K 10.15

A 3.057 Glaciation Glaciation

A 1.38

A 2.30

E GEN-21

J 5.42

S 047

W 1.062

K 10.16

A 1.39 Global effects Climate evolution

K 10.10 Greenhouse effect Climate evolution

A 2.31

A 3.059

W 3.047

H 3.1.4 Intensification of natural climate change

Climate evolution

A 2.38 Isostatic rebound Land uplift and depression

A 2.48 Ozone layer failure Climate evolution

A 3.078

N 1.3.5 Periglacial effects Permafrost formation

M 1.3.05

E GEN-26 Permafrost Permafrost formation

J 5.17

K 10.13

S 059

W 1.063

K 8.29 Precipitation (meteoric) Climate evolution

W 1.059

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Explanatory note

A 3.081

K 10.01 Present-day climatic conditions Climate evolution

I 266 Sea level change Climate evolution, Land uplift and depression

A 2.59

E GEN-33

S 081

W 1.068

M 1.3.04

N 1.3.4

K 10.03 Seasonality of climate Climate evolution

A 3.090 Seasons Climate evolution

M 1.1.02 Solar insolation Climate evolution

K 9.06 Stress changes - hydrogeological effects

NA Not a specific external FEP - These changes and ef-fects are taken into account within the GEOSPHERE FEPs Groundwater flow and advective transport and Reactivation-displacements of existing fractures

W 1.060 Temperature Climate evolution

A 1.81 Temperature effects Climate evolution

E GEN-39 Uplift and subsidence Land uplift and depression

J 5.16

M 1.2.06

K 10.09 Warmer climate - equable humid Climate evolution

K 10.08 Warmer climate - seasonal humid Climate evolution

References

Performance Assessment Safety case for the disposal of spent nuclear fuel at Olkiluoto - Performance Assessment 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-04. ISBN 978-951-652-185-8.

Site Description Olkiluoto Site Description 2011. Eurajoki, Finland: Posiva Oy. POSIVA 2011-02. ISBN 978-951-652-179-7.

111

APPENDIX C. CROSS-CHECK AGAINST SR-SITE

Table C-1. Cross-checking against SR-Site FEP catalogue (SKB 2010a, Tables 5-1...5-12, Sections 5.6, 5.7 and 5.8 and Appendix 2). The FEP numbers (first column) and FEP names refer to SR-Site FEPs, and the third column shows the FEP(s) of the TURVA-2012 FEP list that is mapped to the SR-Site FEP in question. FEPs included in the SR-Site FEP catalogue but excluded from the assessment (cf. SKB 2010a, Sections 4.2 and 4.3.4) are shown in grey. Surface environment FEPs are out of scope of this report. See Appendix A for the TURVA-2012 FEP codes used in the table.

FEP FEP name Mapped to Notes

Initial state FEPs

ISGen01 Major mishaps/accidents/sabotage (ex-cluded from the SR-Site assessment)

Relates to operational safety, thus outside the scope of TURVA-2012.

ISGen02 Effects of phased operation Operation schedule is handled elsewhere in TURVA-2012 (e.g. waste emplacement schedule used in thermal dimen-sioning).

ISGen03 Incomplete closure Out of the scope of the post-closure safety case TURVA-2012 that as-sumes the disposal facil-ity to be properly closed.

ISGen04 Monitoring activities (excluded from the SR-Site assessment)

Handled elsewhere in TURVA-2012 (consid-ered in repository de-sign).

ISC01 Mishaps – canister Canister handling acci-dents discussed in Per-formance Assessment but not included as a FEP, as any canister damaged during opera-tion is assumed to be replaced. Operational safety is outside the scope of TURVA-2012.

ISC02 Design deviations – canister Initial penetrating de-fect(s) assumed in sev-eral radionuclide release scenarios.

ISBu01 Mishaps – buffer Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to buffer production and em-placement. QC issues are related to assess-ment methodology and

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are handled elsewhere in TURVA-2012.

ISBu02 Design deviations – buffer Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to buffer production and em-placement. QC issues are related to assess-ment methodology and are handled elsewhere in TURVA-2012.

ISBfT01 Mishaps – backfill in tunnels Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to backfill production and em-placement. QC issues are related to assess-ment methodology and are handled elsewhere in TURVA-2012.

ISBfT02 Design deviations – backfill in tunnels Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to backfill production and em-placement. QC issues are related to assess-ment methodology and are handled elsewhere in TURVA-2012.

ISBP01 Mishaps – bottom plate in deposition holes

The bottom plate is not a component in Posiva’s current repository de-sign.

ISBP02 Design deviations – bottom plate in deposition holes

The bottom plate is not a component in Posiva’s current repository de-sign.

ISPg01 Mishaps – plugs Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to the pro-duction and emplace-ment of closure plugs (auxiliary components). QC issues are related to assessment methodol-ogy and are handled elsewhere in TURVA-2012.

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ISPg02 Design deviations – plugs Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to the pro-duction and emplace-ment of closure plugs (auxiliary components). QC issues are related to assessment methodol-ogy and are handled elsewhere in TURVA-2012.

ISCA01 Mishaps – central area Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to the selec-tion, production and emplacement of closure materials and structures. QC issues are related to assessment methodol-ogy and are handled elsewhere in TURVA-2012.

ISCA02 Design deviations – central area Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to the em-placement of closure materials and structures. QC issues are related to assessment methodol-ogy and are handled elsewhere in TURVA-2012.

ISTS01 Mishaps/Design deviations – top seal Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to the em-placement of closure materials and structures. QC issues are related to assessment methodol-ogy and are handled elsewhere in TURVA-2012.

ISBhS01 Mishaps/Design deviations – borehole seals

Out of scope of TURVA-2012. It is assumed that quality control (QC) measures are success-fully applied to the em-placement of borehole seals. QC issues are related to assessment

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methodology and are handled elsewhere in TURVA-2012.

Process FEPs for the system component Fuel/cavity in canister

F01 Radioactive decay 3.2.1

F02 Radiation attenuation/heat generation 4.2.1/3.2.2

F03 Induced fission (criticality) 3.2.11

F04 Heat transport 3.2.3

F05 Water and gas transport in canister cav-ity, boiling/condensation

4.3.4, 4.3.5, 4.3.7

F06 Mechanical cladding failure Not a FEP in itself in TURVA-2012, but the potential consequence of other FEPs, such as e.g. 3.2.7, 4.2.3.

F07 Structural evolution of fuel matrix FU1.1, 3.2.4, 3.2.8

F08 Advection and diffusion 3.3.4, 4.3.4, 4.3.5

F09 Residual gas radiolysis/acid formation 3.2.5, 3.2.6

F10 Water radiolysis 3.2.5, 3.2.6

F11 Metal corrosion 3.2.7

F12 Fuel dissolution 3.2.8, 3.3.1

F13 Dissolution of gap inventory 3.2.9

F14 Speciation of radionuclides, colloid for-mation

3.3.1, 3.3.2

F15 Helium production 3.2.10

F16 Chemical alteration of the fuel matrix 3.2.8

F17 Radionuclide transport 3.3.1, 3.3.2, 3.3.3, 3.3.4

Process FEPs for the system component Cast iron insert and copper canister

C01 Radiation attenuation/heat generation 4.2.1, 4.2.2

C02 Heat transport 4.2.2

C03 Deformation of cast iron insert 4.2.3

C04 Deformation of copper canister from external pressure

4.2.3

C05 Thermal expansion (both cast iron insert and copper canister)

4.2.4

C06 Copper deformation from internal corro-sion products

4.2.3

C07 Radiation effects 4.2.1

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C08 Corrosion of cast iron insert 4.2.6

C09 Galvanic corrosion 4.2.5, 4.2.6

C10 Stress corrosion cracking of cast iron insert

4.2.7

C11 Corrosion of copper canister 4.2.5

C12 Stress corrosion cracking, copper canis-ter

4.2.7

C13 Earth currents – stray current corrosion Excluded already in Posiva’s previous Proc-ess Report (Miller & Marcos 2007) because the FEP has insignificant consequences as re-ported in SR-Can.

C14 Deposition of salts on canister surface 4.2.5, 4.3.2

C15 Radionuclide transport 4.3.1−4.3.7

Process FEPs for the system component Buffer

Bu01 Radiation attenuation/heat generation 5.2.1

Bu02 Heat transport 5.2.1

Bu03 Freezing 5.2.9

Bu04 Water uptake and transport for unsatu-rated conditions

5.2.2, 5.3.4

Bu05 Water transport for saturated conditions 5.3.4, 5.3.5

Bu06 Gas transport/dissolution 5.3.7

Bu07 Piping/erosion 5.2.3

Bu08 Swelling/mass redistribution 5.2.2

Bu09 Liquefaction Not relevant. Disre-garded also in SR-Site since liquefaction from a short pulse cannot occur in a high density ben-tonite, due to high effec-tive stresses (SKB 2010b, Table 2-4).

Bu10 Advective transport of species 5.3.5

Bu11 Diffusive transport of species 5.3.4

Bu12 Sorption (including exchange of major ions)

5.3.3

Bu13 Alterations of impurities 5.2.7

Bu14 Aqueous speciation and reactions 5.3.1

Bu15 Osmosis 5.3.4

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Bu16 Montmorillonite transformation 5.2.6

Bu17 Iron-bentonite interaction 5.2.6, 5.2.7

Bu18 Montmorillonite colloid release 5.2.4, 5.3.6

Bu19 Radiation-induced transformations 5.2.5, 5.2.7 Not an actual FEP in itself, but the conse-quences, if any, are considered under 5.2.6 and 5.2.7 (though stud-ies suggest that no ra-diation-induced trans-formations are expected at all).

Bu20 Radiolysis of porewater 5.2.5

Bu21 Microbial processes 5.2.8

Bu22 Cementation 5.2.6, 5.2.7

Bu23 Colloid transport 5.3.6

Bu24 Speciation of radionuclides 5.3.1

Bu25 Transport of radionuclides in the water phase

5.3.2, 5.3.4, 5.3.5

Bu26 Transport of radionuclides in a gas phase 5.3.7

Process FEPs for the system component Backfill in tunnels

BfT01 Heat transport 6.2.1

BfT02 Freezing 6.2.8, 7.2.3

BfT03 Water uptake and transport for unsatu-rated conditions

6.2.2, 6.3.4

BfT04 Water transport for saturated conditions 6.3.4, 6.3.5, 7.3.1

BfT05 Gas transport/dissolution 6.3.7

BfT06 Piping/erosion 6.2.3, 7.2.2

BfT07 Swelling/mass redistribution 6.2.2

BfT08 Liquefaction Not relevant. Disre-garded also in SR-Site as not relevant (SKB 2010b, Table 2-9).

BfT09 Advective transport of species 6.3.5, 7.3.1

BfT10 Diffusive transport of species 6.3.4, 7.3.1

BfT11 Sorption (including exchange of major ions)

6.3.3, 7.3.1

BfT12 Alterations of backfill impurities 6.2.6, 7.2.1

BfT13 Aqueous speciation and reactions 6.3.1

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BfT14 Osmosis 6.3.4

BfT15 Montmorillonite transformation 6.2.5, 7.2.1

BfT16 Backfill colloid release 6.2.4, 6.3.6

BfT17 Radiation-induced transformations Not a relevant FEP for backfill. Radiation effects on backfill properties were disregarded also in SR-Site (SKB 2010a, p. 132).

BfT18 Microbial processes 6.2.7, 7.2.1

BfT19 Colloid formation and transport 6.2.4, 6.3.6

BfT20 Speciation of radionuclides 6.3.1

BfT21 Transport of radionuclides in the water phase

6.3.1−6.3.6, 7.3.1

BfT22 Transport of radionuclides by a gas phase

6.3.7, 7.3.1

Process FEPs for the system component Geosphere

Ge01 Heat transport 8.2.1

Ge02 Freezing 8.2.9 (10.2.3)

Ge03 Groundwater flow GE2.4, 8.3.5

Ge04 Gas flow/dissolution 8.3.7

Ge05 Displacements in intact rock Not a specific FEP, but taken into account in the modelled rock proper-ties.

Ge06 Reactivation – Displacement along exist-ing discontinuities

8.2.3

Ge07 Fracturing GE1.2, 8.2.3, 8.2.4

Ge08 Creep 8.2.5

Ge09 Surface weathering and erosion Erosion is discussed in Complementary Consid-erations in Section 7.5. Surface weathering effects are considered in the geological model of the Olkiluoto site.

In SR-Site this FEP has been moved under Cli-mate and Biosphere (SKB 2010a, Section 4.1.5).

Ge10 Erosion/sedimentation in fractures 8.2.6

Ge11 Advective transport/mixing of dissolved species

8.3.5

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Ge12 Diffusive transport of dissolved species in fractures and rock matrix

8.3.4

Ge13 Speciation and sorption 8.3.1, 8.3.3

Ge14 Reactions groundwater/rock matrix 8.2.7

Ge15 Dissolution/precipitation of fracture-filling minerals

8.2.6, 8.2.7, 8.3.1, 8.3.2

Ge16 Microbial processes 8.2.10

Ge17 Degradation of grout 7.2.1, 7.2.2, 7.2.3

Ge18 Colloidal processes 8.3.6

Ge19 Formation/dissolution/reaction of gase-ous species

GE2.11, 8.2.8, 8.3.7

Ge20 Methane hydrate formation 8.2.8

Ge21 Salt exclusion 8.2.9

Ge22 Radiation effects (rock and grout) Radiation effects are not significant in the geo-sphere. They were dis-regarded also in SR-Site because of too low radia-tion fluxes (SKB 2010c, Table 1-4).

Ge23 Earth currents Not relevant. Disregarded also in SR-Site since expected electrical poten-tial fields are too small to affect groundwater flow or solute transport (SKB 2010c, Table 1-4).

Ge24 Transport of radionuclides in the water phase

8.3.1−8.3.6

Ge25 Transport of radionuclides in the gas phase

8.3.7

Process FEPs for the system components Tunnel plugs (Pg), Central area (CA), Top seal (TS), Bot-tom plate in deposition holes (BP) and Borehole seals (BhS)

BP01, Pg01, CA01, TS01, BhS01

Heat transport (6.2.1) 7.2.3 Processes in the closure backfill assumed to be similar to those in the deposition tunnel backfill. In other auxiliary compo-nents, this FEP is not specifically included, although it is taken into account in the thermal dimensioning of the re-

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pository.

BP02, Pg02, CA02, TS02, BhS02

Freezing (6.2.8) 7.2.3

BP03, Pg03, CA03, TS03, BhS03

Water uptake and transport under un-saturated conditions

7.3.1

BP04, Pg04, CA04, TS04, BhS04

Water transport under saturated condi-tions

7.3.1

BP05, Pg05, CA05, TS05, BhS05

Gas transport/dissolution (6.3.7) FEP not significant for closure components other than closure backfill (where processes are assumed similar to those in the deposition tunnel backfill).

BP06, Pg06, CA06, TS06, BhS06

Piping/erosion (6.2.3) 7.2.2

BP07, Pg07, CA07, TS07, BhS07

Swelling/mass redistribution (6.2.2) FEP not discussed spe-cifically for Auxiliary components, but if they contain clay, discussion in 6.2.2 generally applies.

Pg08, CA08, TS08, BhS08

Liquefaction Not relevant. Disregarded also in SR-Site, since impact is low (in central area backfill) or cannot occur at all (in other components) (SKB 2010b, Tables 2-14 and 2-16).

BP08, Pg09, CA09, TS09, BhS09

Advective transport of species (6.3.5) 7.3.1

BP09, Pg10, CA10, TS10, BhS10

Diffusive transport of species (6.3.4) 7.3.1

BP10, Pg11, TS11, BhS11

Sorption (including exchange of major ions)

(6.3.3) 7.3.1

CA11 Sorption (6.3.3) 7.3.1

CA12 Alteration of central area backfill (6.2.5, 6.2.6)

BP11, Alteration of concrete 7.2.1

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Pg12, TS12, BhS12

CA15 Alteration of concrete components 7.2.1, 7.2.2

BP12, Pg13, CA13, TS13, BhS13

Aqueous speciation and reactions The FEP is discussed for buffer and backfill but not explicitly for auxiliary components.

BP13, BhS14

Copper corrosion 7.2.1 Degradation of metal parts is discussed under 7.2.1. Copper may be used in some auxiliary components, such as in certain borehole seals (Feature, Events and Processes, Section 7.1).

BhS15 Alterations of impurities in bentonite (6.2.6)

Pg14, CA14, BhS16

Osmosis (6.3.4), 7.3.1 FEP not significant for closure components other than closure back-fill.

Pg15, BhS17

Montmorillonite transformation (6.2.5), 7.2.1

Pg16, BhS18

Montmorillonite colloid release (6.2.4, 6.3.6) FEP not significant for closure components other than closure back-fill.

TS14 Colloid release 7.3.1

TS15 Steel corrosion 7.2.1 Degradation of metal parts is discussed under 7.2.1. Steel is anticipated to be the most used metal in the concrete structures (Feature, Events and Processes, Section 7.1).

CA16 Corrosion of steel components 7.2.1 Degradation of metal parts is discussed under 7.2.1. Steel is anticipated to be the most used metal in the concrete structures (Feature, Events and Processes, Section 7.1).

BP14, Pg17, CA17, TS16, BhS19

Microbial processes (6.2.7,) 7.2.1

BP15, Pg18, CA18, TS17, BhS21

Speciation of radionuclides (6.3.1) FEP not significant for closure components other than closure back-fill, in which case discus-sion under 6.3.1 applies.

BP16, Pg19,

Transport of radionuclides in the water phase

7.3.1

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CA19, TS18, BhS22

Variable FEPs for the system component “Fuel/cavity in canister”

VarF01 Radiation intensity FU2.1 Radiation intensity de-pends on the radionu-clide inventory.

VarF02 Temperature FU2.2

VarF03 Hydrovariables (pressure and flow) FU1.3, FU2.3

VarF04 Fuel geometry FU2.4

VarF05 Mechanical stresses FU2.5

VarF06 Radionuclide inventory FU2.1

VarF07 Material composition FU2.6

VarF08 Water composition FU2.7

VarF09 Gas composition FU2.8

Variable FEPs for the system component “Cast iron insert and copper canister”

VarC01 Radiation intensity CA2.1, 4.2.1 Radiation intensity de-pends on the radionu-clide inventory.

VarC02 Temperature CA2.2

VarC03 Canister geometry CA2.4

VarC04 Material composition CA2.6

VarC05 Mechanical stresses CA2.5

Variable FEPs for the system component “Buffer”

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VarBu01 Radiation intensity Taken into account in 5.2.5, but not a feature of the buffer in itself.

VarBu02 Temperature BU2.2

VarBu03 Water content BU2.5

VarBu04 Gas content BU1.2, BU2.8

VarBu05 Hydrovariables (pressure and flow) BU1.3, BU2.5, BU2.3, 5.3.5

VarBu06 Buffer geometry BU2.4

VarBu07 Pore geometry BU1.2

VarBu08 Stress state Taken into account in 5.2.2, but not a feature of the buffer in itself.

VarBu09 Bentonite composition BU2.6

VarBu10 Montmorillonite composition BU2.6

VarBu11 Porewater composition BU2.7

VarBu12 Structural and stray materials BU2.6 In TURVA-2012, the only foreign materials as-sumed to be located in the deposition holes are the bentonite accessory minerals.

Variable FEPs for the system component “Backfill in tunnels”

VarBfT01 Temperature BA2.2

VarBfT02 Water content BA2.5

VarBfT03 Gas content BA1.2, BA2.8

VarBfT04 Hydrovariables (pressure and flow) BA1.3, BA2.5, BA2.3, 6.3.5

VarBfT05 Backfill geometry BA2.4

VarBfT06 Backfill pore geometry BA1.2

VarBfT07 Stress state Taken into account in 6.2.2, but not a feature of the backfill in itself.

VarBfT08 Backfill materials - composition and con-tent

BA2.6

VarBfT09 Backfill porewater composition BA2.7

VarBfT10 Structural and stray materials Auxiliary compo-nents, BA2.6

Variable FEPs for the system component “Geosphere”

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VarGe01 Temperature GE2.2

VarGe02 Groundwater flow GE2.4

VarGe03 Groundwater pressure GE2.3

VarGe04 Gas phase flow GE2.11, 8.3.7

VarGe05 Repository geometry GE2.6

VarGe06 Fracture geometry GE2.7

VarGe07 Rock stresses GE2.5

VarGe08 Matrix minerals GE2.8

VarGe09 Fracture minerals GE2.9

VarGe10 Groundwater composition GE2.10

VarGe11 Gas composition GE2.11

VarGe12 Structural and stray materials Auxiliary compo-nents

Grouts injected to the host rock are assumed to be part of auxiliary com-ponents.

VarGe13 Saturation GE1.1 Rock matrix is assumed to be saturated also around the near field soon after closure.

Variable FEPs for the system component “Bottom plate in deposition holes” - These FEPs are ex-cluded (not a component in Posiva’s current repository design)

Variable FEPs for the system component “Plugs”

VarPg01 Temperature AU2.2

VarPg02 Water content AU1.2

VarPg03 Gas content AU2.6

VarPg04 Hydrovariables (pressure and flow) AU1.2, AU2.3

VarPg05 Plug geometry AU1.1 Inherent to repository geometry.

VarPg06 Plug pore geometry AU2.6 Will depend on material composition.

VarPg07 Stress state Will vary according to water uptake and swell-ing in the clay compo-nents of the plugs.

VarPg08 Plug materials – composition and content AU2.6

VarPg09 Plug porewater composition AU2.6

VarPg10 Structural and stray materials Auxiliary compo-nents

Considered part of Auxil-iary components, al-though not discussed in

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detail in the FEP report.

Variable FEPs for the system component “Central area”1

VarCA01 Temperature BA2.2, AU2.2 Variables in the closure backfill assumed to be similar to those in the deposition tunnel backfill.

VarCA02 Water content BA2.5, AU1.2

VarCA03 Gas content AU2.6

VarCA04 Hydrovariables (pressure and flow) BA1.3, AU1.2, AU2.3

VarCA05 Central area geometry AU2.4 Will depend on repository geometry.

VarCA06 Central area pore geometry AU2.6 Will depend on material composition.

VarCA07 Stress state Will vary according to water uptake and swell-ing in the clay compo-nents of the central ar-eas.

VarCA08 Central area materials – composition and content

BA2.6, AU2.6

VarCA09 Central area porewater composition BA2.7, AU2.7 Will depend on ground-water and material com-position.

VarCA10 Structural and stray materials Auxiliary compo-nents

Considered part of Auxil-iary components, al-though not discussed in detail in the FEP report.

Variable FEPs for the system component “Top seal”

VarTS01 Temperature AU2.2

VarTS02 Water content AU1.2

VarTS03 Gas content AU2.6

VarTS04 Hydrovariables (pressure and flow) AU1.2, AU2.3

VarTS05 Top seal geometry AU1.1, AU2.4 Will depend on repository geometry.

VarTS06 Top seal pore geometry AU2.6

VarTS07 Stress state AU2.3 Will vary according to water uptake and swell-

1 In SR-Site, this system component comprises the part below 200 m depth of the subsurface of the KBS-3 repository facility and includes rock cavities for operation, logistics and maintenance. The central area will be filled with crushed rock. This system component also includes engineered and residual materials, such as rock bolts, shotcrete and reinforcement nets that will be used as rock support (SKB 2010a, Section 2.1.2).

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ing in the clay compo-nents of the Top seal.

VarTS08 Top seal materials – composition and content

AU2.6

VarTS09 Top seal porewater composition AU2.7 Will depend on ground-water and material com-position.

VarTS10 Structural and stray materials Auxiliary compo-nents


Variable FEPs for the system component “Borehole seals”

VarBhS01 Temperature AU2.2

VarBhS02 Water content AU1.2

VarBhS03 Gas content AU2.6

VarBhS04 Hydrovariables (pressure and flow) AU1.2, AU2.3

VarBhS05 Borehole geometry AU1.1, AU2.4

VarBhS06 Pore geometry AU2.6

VarBhS07 Stress state AU2.3 Will vary according to water uptake and swell-ing in the clay compo-nents of the borehole seals.

VarBhS08 Sealing materials – composition and content

AU2.6

VarBhS09 Porewater composition AU2.7 Will depend on ground-water and material com-position.

VarBhS10 Structural and stray materials Auxiliary compo-nents


Provisional Biosphere FEPs - These FEPs are excluded (not handled in this report)

Climate FEPs

Cli01 Climate system – Components of the climate system

10.2.1

Cli02 Climate system – Climate forcing 10.2.1

Cli03 Climate system – Climate dynamics 10.2.1

Cli04 Climate system – Climate in Sweden and Forsmark

Climate in Finland and at Olkiluoto is considered (10.2.1).

Cli05 Climate related issues – Development of permafrost

10.2.3

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Cli06 Climate related issues – Ice-sheet dy-namics

10.2.2

Cli07 Climate related issues – Ice-sheet hy-drology

10.2.2

Cli08 Climate related issues – Glacial isostatic adjustment

10.2.4

Cli09 Climate related issues – Shoreline migra-tion

10.2.4

Cli10 Climate related issues – End-glacial faulting

8.2.3, 10.2.2

Cli11 Climate related issues – Denudation 10.2.2

Large-scale geological FEPs

LSGe01 Mechanical evolution of the Shield Not included as a specific FEP because the tectonic situation in the Olkiluoto area is very likely to be stable in the one million year assessment time frame (post-glacial earth-quake effects considered in FEP 8.2.3 and in the RS and RS-DIL scenar-ios).

LSGe02 Earthquakes 8.2.3, 10.2.4 This FEP is not explicitly included, but its causes and consequences are discussed under 10.2.4 and 8.2.3. Nonetheless the subject is broadly discussed in Comple-mentary Considerations.

FHA (Future Human Actions) FEPs

FHA01 General considerations Not a FEP in itself, but relates to assessment methodology (projected to the near future).

FHA02 Societal analysis, considered societal aspects

Not a FEP in itself, but relates to assessment methodology (projected to the near future).

FHA03 Technical analysis, general aspects Not a FEP in itself, but relates to assessment methodology (projected to the near future).

FHA04 Technical analysis, actions with thermal impact and purpose

10.2.5 May include intrusion into the repository via drilling.

FHA05 Technical analysis, actions with hydraulic impact and purpose


FHA06 Technical analysis, actions with me-chanical impact and purpose


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FHA07 Technical analysis, actions with chemical impact and purpose


Other

Oth01 Meteorite impact (excluded from the SR-Site assessment)

Not included as it is re-lated to much more seri-ous consequences than any radiological impact from the spent nuclear fuel. Nonetheless dealt with in Complementary Considerations

Site-specific factors

SiteFact02 Construction of nearby rock facilities Taken into account in the site selection process. Dealt with elsewhere in the construction licence application (CLA) – also in Olkiluoto Site Descrip-tive model (OSD).

SiteFact03 Nearby nuclear power plant Taken into account in the site selection process. Dealt with elsewhere in the CLA.

SiteFact04 Mine excavation Taken into account in the site selection process. Dealt with elsewhere in the CLA – also OSD.

Methodology issues

Meth01 Assessment basis Related to assessment methodology and thus handled elsewhere in TURVA-2012.

Meth02 Assessment methodology Handled elsewhere in TURVA-2012.

Table C-2. Mapping of TURVA-2012 process FEPs to FEPs in the SR-Site FEP cata-logue (SKB 2010a, Tables 5-1...5-12, Sections 5.6, 5.7 and 5.8 and Appendix 2). Surface environment FEPs not included.

FEP number in TURVA-2012

FEP name in TURVA-2012 Mapped to Process FEP in SR-Site

(FEP number: FEP name)

Process FEPs in the spent nuclear fuel:

3.2.1 Radioactive decay (and in-growth) F01: Radioactive decay

3.2.2 Heat generation F02: Radiation attenuation/heat generation

3.2.3 Heat transfer F04: Heat transport

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3.2.4 Structural alteration of the fuel pellets F07: Structural evolution of fuel matrix


F09: Residual gas radiolysis/acid formation F10: Water radiolysis

3.2.6 Radiolysis of the canister water F09: Residual gas radiolysis/acid formation F10: Water radiolysis


F11: Metal corrosion

3.2.8 Alteration and dissolution of the fuel matrix F07: Structural evolution of fuel matrix F12: Fuel dissolution F16: Chemical alteration of the fuel matrix


F13: Dissolution of GAP inventory

3.2.10 Production of helium gas F15: Helium production

3.2.11 Criticality F03: Induced fission (criticality)

3.3.1 Aqueous solubility and speciation F12: Fuel dissolution F14: Speciation of radionuclides, colloid forma-tion F17: Radionuclide transport

3.3.2 Precipitation and co-precipitation F14: Speciation of radionuclides, colloid forma-tion F17: Radionuclide transport

3.3.3 Sorption F17: Radionuclide transport

3.3.4 Diffusion in fuel pellets F08: Advection and diffusion F17: Radionuclide transport

Process FEPs in the canister: 4.2.1 Radiation attenuation F02: Radiation attenuation/heat generation

C01: Radiation attenuation/ heat generation C07: Radiation effects

4.2.2 Heat transfer C01: Radiation attenuation/ heat generation C02: Heat transport

4.2.3 Deformation C03: Deformation of cast iron insert C04: Deformation of copper canister from external pressure C06: Copper deformation from internal corro-sion products

4.2.4 Thermal expansion of the canister C05: Thermal expansion (both cast iron insert and copper canister)

4.2.5 Corrosion of the copper overpack C09: Galvanic corrosion C11: Corrosion of copper canister C14: Deposition of salts on canister surface

4.2.6 Corrosion of the cast iron insert C08: Corrosion of cast iron insert C09: Galvanic corrosion

4.2.7 Stress corrosion cracking C10: Stress corrosion cracking of the cast iron insert C12: Stress corrosion cracking of the copper canister

4.3.1 Aqueous solubility and speciation C15: Radionuclide transport

4.3.2 Precipitation and co-precipitation C14: Deposition of salts on canister surface C15: Radionuclide transport

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4.3.3 Sorption C15: Radionuclide transport

4.3.4 Diffusion F05: Water and gas transport in canister cav-ity, boiling/condensation F08: Advection and diffusion C15: Radionuclide transport

4.3.5 Advection F05: Water and gas transport in canister cav-ity, boiling/condensation F08: Advection and diffusion C15: Radionuclide transport

4.3.6 Colloid transport C15: Radionuclide transport

4.3.7 Gas transport F05: Water and gas transport in canister cav-ity, boiling/condensation C15: Radionuclide transport

Process FEPs in the buffer: 5.2.1 Heat transfer Bu01: Radiation attenuation/heat generation

Bu02: Heat transport

5.2.2 Water uptake and swelling Bu04: Water uptake and transport for unsatu-rated conditions Bu08: Swelling/mass redistribution

5.2.3 Piping and erosion Bu07: Piping/erosion

5.2.4 Chemical erosion Bu18: Montmorillonite colloid release

5.2.5 Radiolysis of porewater Bu19: Radiation-induced transformations Bu20: Radiolysis of porewater

5.2.6 Montmorillonite transformation Bu16: Montmorillonite transformation Bu17: Iron-bentonite interaction Bu22: Cementation

5.2.7 Alteration of accessory minerals Bu13: Alterations of impurities Bu17: Iron-bentonite interaction Bu19: Radiation-induced transformations Bu22: Cementation

5.2.8 Microbial activity Bu21: Microbial processes

5.2.9 Freezing and thawing Bu03: Freezing

5.3.1 Aqueous solubility and speciation Bu14: Aqueous speciation and reactions Bu24: Speciation of radionuclides

5.3.2 Precipitation and co-precipitation Bu25: Transport of radionuclides in the water phase

5.3.3 Sorption Bu12: Sorption (including exchange of major ions)

5.3.4 Diffusion Bu04: Water uptake and transport for unsatu-rated conditions Bu05: Water transport for saturated conditions Bu11: Diffusive transport of species Bu15: Osmosis Bu25: Transport of radionuclides in the water phase

5.3.5 Advection Bu05: Water transport for saturated conditions Bu10: Advective transport of species Bu25: Transport of radionuclides in the water phase

5.3.6 Colloid transport Bu18: Montmorillonite colloid release Bu23: Colloid transport

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5.3.7 Gas transport Bu06: Gas transport/dissolution Bu26: Transport of radionuclides in a gas phase

Process FEPs in the tunnel backfill: 6.2.1 Heat transfer BfT01: Heat transport

6.2.2 Water uptake and swelling BfT03: Water uptake and transport for unsatu-rated conditions BfT07: Swelling/mass redistribution

6.2.3 Piping and erosion BfT06: Piping/erosion

6.2.4 Chemical erosion BfT16: Backfill colloid release BfT19: Colloid formation and transport

6.2.5 Montmorillonite transformation BfT15: Montmorillonite transformation

6.2.6 Alteration of accessory minerals BfT12: Alterations of backfill impurities

6.2.7 Microbial activity BfT18: Microbial processes

6.2.8 Freezing and thawing BfT02: Freezing

6.3.1 Aqueous solubility and speciation BfT13: Aqueous speciation and reactions BfT20: Speciation of radionuclides BfT21: Transport of radionuclides in the water phase

6.3.2 Precipitation and co-precipitation BfT21: Transport of radionuclides in the water phase

6.3.3 Sorption BfT11: Sorption (including exchange of major ions) BfT21: Transport of radionuclides in the water phase

6.3.4 Diffusion BfT03: Water uptake and transport for unsatu-rated conditions BfT04: Water transport for saturated conditions BfT10: Diffusive transport of species BfT14: Osmosis BfT21: Transport of radionuclides in the water phase

6.3.5 Advection BfT04: Water transport for saturated conditions BfT09: Advective transport of species BfT21: Transport of radionuclides in the water phase

6.3.6 Colloid transport BfT16: Backfill colloid release BfT19: Colloid formation and transport BfT21: Transport of radionuclides in the water phase

6.3.7 Gas transport BfT05: Gas transport/dissolution BfT22: Transport of radionuclides by a gas phase

Process FEPs in the auxiliary components:

7.2.1 Chemical degradation

BfT12: Alterations of backfill impurities BfT15: Montmorillonite transformation: BfT18: Microbial processes Ge17: Degradation of grout BP11, Pg12, TS12, BhS12: Alteration of con-crete CA15: Alteration of concrete components

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BP13, BhS14: Copper corrosion Pg15, BhS17: Montmorillonite transformation TS15: Steel corrosion CA16: Corrosion of steel components BP14, Pg17, CA17, TS16, BhS19: Microbial processes

7.2.2 Physical degradation

BfT06: Piping/erosion Ge17: Degradation of grout BP06, Pg06, CA06, TS06, BhS06: Pip-ing/erosion CA15: Alteration of concrete components

7.2.3 Freezing and thawing

BfT02: Freezing Ge17: Degradation of grout BP01, Pg01, CA01, TS01, BhS01: Heat trans-port BP02, Pg02, CA02, TS02, BhS02: Freezing

7.3.1 Transport through auxiliary components

BfT04: Water transport for saturated conditions BfT09: Advective transport of species BfT10: Diffusive transport of species BfT11: Sorption (including exchange of major ions) BfT21: Transport of radionuclides in the water phase BfT22: Transport of radionuclides by a gas phase BP03, Pg03, CA03, TS03, BhS03: Water up-take and transport under unsaturated condi-tions BP04, Pg04, CA04, TS04, BhS04: Water transport under saturated conditions BP08, Pg09, CA09, TS09, BhS09: Advective transport of species BP09, Pg10, CA10, TS10, BhS10: Diffusive transport of species BP10, Pg11, TS11, BhS11: Sorption (including exchange of major ions) CA11: Sorption Pg14, CA14, BhS16: Osmosis TS14: Colloid release BP16, Pg19, CA19, TS18, BhS22: Transport of radionuclides in the water phase

Process FEPs in the geosphere: 8.2.1 Heat transfer Ge01: Heat transport

8.2.2 Stress redistribution Ge07, VarGe07, Ge05, Ge06


Ge06: Reactivation – Displacement along existing discontinuities Ge07: Fracturing Cli10: Climate related issues – End-glacial faulting LSGe02: Earthquakes

8.2.4 Spalling Ge07: Fracturing

8.2.5 Creep Ge08: Creep

8.2.6 Erosion and sedimentation in fractures Ge10: Erosion/sedimentation in fractures Ge15: Dissolution/precipitation of fracture-

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filling minerals

8.2.7 Rock-water interaction Ge14: Reactions groundwater/rock matrix Ge15: Dissolution/precipitation of fracture-filling minerals

8.2.8 Methane hydrate formation Ge19: Formation/dissolution/reaction of gase-ous species Ge20: Methane hydrate formation

8.2.9 Salt exclusion Ge02: Freezing Ge21: Salt exclusion

8.2.10 Microbial activity Ge16: Microbial processes

8.3.1 Aqueous solubility and speciation

Ge13: Speciation and sorption Ge15: Dissolution/precipitation of fracture-filling minerals Ge24: Transport of radionuclides in the water phase

8.3.2 Precipitation and co-precipitation

Ge15: Dissolution/precipitation of fracture-filling minerals Ge24: Transport of radionuclides in the water phase

8.3.3 Sorption Ge13: Speciation and sorption Ge24: Transport of radionuclides in the water phase

8.3.4 Diffusion and matrix diffusion

Ge12: Diffusive transport of dissolved species in fractures and rock matrix Ge24: Transport of radionuclides in the water phase

8.3.5 Groundwater flow and advective transport

Ge03: Groundwater flow Ge11: Advective transport/mixing of dissolved species Ge24: Transport of radionuclides in the water phase

8.3.6 Colloid transport Ge18: Colloidal processes Ge24: Transport of radionuclides in the water phase

8.3.7 Gas transport

Ge04: Gas flow/dissolution Ge19: Formation/dissolution reaction of gase-ous species Ge25: Transport of radionuclides in the gas phase

Process FEPs external to the disposal system:

10.2.1 Climate evolution

Cli01: Climate system – Components of the climate system Cli02: Climate system – Climate forcing Cli03: Climate system – Climate dynamics

10.2.2 Glaciation

Cli06: Climate related issues – Ice sheet dy-namics Cli07: Climate related issues – Ice sheet hy-drology Cli10: Climate related issues – End-glacial faulting Cli11: Climate related issues – Denudation

10.2.3 Permafrost formation Cli05: Climate related issues – Development of Permafrost

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10.2.4 Land uplift and depression

Cli08: Climate related issues – Glacial isostatic adjustment Cli09: Climate related issues – Shoreline mi-gration LSGe02: Earthquakes

10.2.5 Inadvertent human intrusion

FHA04: Technical analysis, actions with ther-mal impact and purpose FHA05: Technical analysis, actions with hy-draulic impact and purpose FHA06: Technical analysis, actions with me-chanical impact and purpose FHA07: Technical analysis, actions with chemical impact and purpose

References

Complementary Considerations Safety case for the disposal of spent nuclear fuel at Olkiluoto - Complementary Consid-erations 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-11. ISBN 978-951-652-192-6.

Features, Events and Processes Safety case for the disposal of spent nuclear fuel at Olkiluoto – Features, Events and Processes 2012. Eurajoki, Finland: Posiva Oy. POSIVA 2012-07. ISBN 978-951-652-188-9.

Miller, B. & Marcos, N. 2007. Process report. FEPs and scenarios for a spent fuel re-pository at Olkiluoto. Eurajoki, Finland: Posiva Oy. POSIVA 2007-12. 274 p. ISBN 978-951-652-162-9.

SKB 2010a. FEP report for the safety assessment SR-Site. Stockholm, Sweden: Swed-ish Nuclear Fuel and Waste Management Co. (SKB). Technical Report TR-10-45. 269 p. ISSN 1404-0344.

SKB 2010b. Buffer, backfill and closure process report for the safety assessment SR-Site. Stockholm, Sweden: Swedish Nuclear Fuel and Waste Management Co. (SKB). Technical Report TR-10-47. 360 p. ISSN 1404-0344.

SKB 2010c. Geosphere process report for the safety assessment SR-Site. Stockholm, Sweden: Swedish Nuclear Fuel and Waste Management Co. (SKB). Technical Report TR-10-48. 271 p. ISSN 1404-0344.

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APPENDIX D. CROSS-CHECK AGAINST THE FOURTH CASE STUDY

Table D-1. Cross-checking against NWMO’s Fourth Case Study FEP list (Garisto 2012, Tables 2.1, 2.2, 2.3). The FEP numbers (first column) and FEP names refer to the FEPs in the Fourth Case Study FEP list, and the third column shows the FEP(s) of the TURVA-2012 FEP list that can be mapped to the Fourth Case Study FEP in question. FEPs that were screened out in Garisto (2012) are shown in grey. N.A. = not applica-ble (to Posiva’s site or concept). Surface environment FEPs are not considered here (out of the scope of this report). See Appendix A for the TURVA-2012 FEP codes used in the table.


ASSESSMENT BASIS FEPS

0. 0 Assessment basis

0.0.01 Aims of the assessment Related to assessment method-ology and handled elsewhere in TURVA-2012.

0.0.02 Regulatory requirements and exclusions

Related to assessment method-ology and handled elsewhere in TURVA-2012.

0.0.03 Impacts of concern Related to assessment method-ology and handled elsewhere in TURVA-2012.

0.0.04 Time scales of concern Related to assessment method-ology and handled elsewhere in TURVA-2012.

0.0.05 Spatial domain of concern Related to assessment method-ology and handled elsewhere in TURVA-2012.

0.0.06 Repository assumptions Related to assessment method-ology and handled elsewhere in TURVA-2012.

0.0.07 Future human action assump-tions

10.2.5 (Surface environment FEPs not considered here.)

0.0.08 Future human behaviour (target group) assumptions

(Surface environment FEPs not considered here.)

0.0.09 Dose response assumptions (Surface environment FEPs not considered here.)

EXTERNAL FEPS

1.1 Repository Issues

1.1.01 Site investigation Geosphere Related to Olkiluoto site investi-gation and handled elsewhere – Related to the component GEOSPHERE.

1.1.02 Excavation and construction Geosphere Excavation effects (EDZ) han-dled in groundwater flow model-

136

ling variants – Related to the component GEOSPHERE.

1.1.03 Placement of wastes and backfill Related to the operational phase and handled elsewhere in TURVA-2012.

1.1.04 Closure and repository sealing Auxiliary components

1.1.05 Repository records and markers Out of the scope of TURVA-2012.

1.1.06 Waste allocation Related to the layout of reposi-tory handled elsewhere in TURVA-2012.

1.1.07 Repository design Repository design is handled elsewhere in TURVA-2012 (e.g. layout designs used by ground-water flow modelling; waste emplacement schedule used in thermal dimensioning).

1.1.08 Quality control QC issues are related to as-sessment methodology and are handled elsewhere in TURVA-2012.

1.1.09 Schedule and planning Schedule issues are handled elsewhere in TURVA-2012 (e.g. waste emplacement schedule used in thermal dimensioning).

1.1.10 Repository administrative control Out of the scope of TURVA-2012.

1.1.11 Monitoring Handled elsewhere in TURVA-2012 (considered in repository design).

1.1.12 Accidents and unplanned events (OUT)


1.1.13 Retrieval of wastes (OUT) Handled elsewhere in TURVA-2012.

1.2 Geological Processes and Effects

1.2.01 Tectonic movement and orogeny (OUT)

N.A.

1.2.02 Deformation (elastic, plastic or brittle)

8.2.3, 8.2.4, 8.2.5

1.2.03 Seismicity (earthquakes) 8.2.3, 10.2.4

1.2.04 Volcanic and magmatic activity (OUT)

N.A.

1.2.05 Metamorphism (OUT) N.A.

1.2.06 Hydrothermal activity (OUT) N.A.

1.2.07 Erosion and sedimentation

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(OUT)

1.2.08 Diagenesis (OUT) N.A.

1.2.09 Salt diapirism and dissolution (OUT)

N.A.

1.2.10 Hydrological response to geo-logical changes

8.3.5, 10.2.2 Not a specific FEP but handled in interaction matrices.

1.3 Climate Processes and Effects

1.3.01 Global climate change 10.2.1

1.3.02 Local and regional climate change

10.2.1

1.3.03 Sea-level change (OUT) (Surface environment FEPs not considered here.)

1.3.04 Periglacial effects 10.2.3

1.3.05 Local glacial effects 10.2.2, 10.2.4

1.3.06 Warm climate effects (tropical and desert) (OUT)

N.A.

1.3.07 Hydrological response to climate changes (OUT)

Not a specific FEP but handled in interaction matrices.

1.3.08 Ecological response to climate changes


1.3.09 Human behavioural response to climate changes


1.4 Future Human Actions

1.4.01 Human influences on climate 10.2.1

1.4.02 Deliberate human intrusion (OUT)


1.4.03 Non-intrusive site investigations (OUT)


1.4.04 Drilling activities (human intru-sion)

10.2.5

1.4.05 Mining (human intrusion) (OUT) 10.2.5

1.4.06 Surface environment, human activities (OUT)


1.4.07 Water management (wells, res-ervoirs, dams)

10.2.5 Relates to human intrusion, if deep drillings are involved.

1.4.08 Social and institutional devel-opments


1.4.09 Technological developments (OUT)


1.4.10 Remedial actions (OUT) Out of the scope of TURVA-

138

2012.

1.4.11 Explosions and crashes (OUT) Out of the scope of TURVA-2012.

1.5 other external factors

1.5.01 Meteorite impact (OUT) Not included as it is related to much more serious conse-quences than any radiological impact from the spent nuclear fuel.

1.5.02 Species evolution (OUT) Out of the scope of TURVA-2012.

1.5.03 Miscellaneous FEPs (OUT) Excluded due to very low prob-ability or no significant effect (cf. Garisto 2012, p. 92).

INTERNAL FEPS CONSIDERED

2. REPOSITORY FACTORS

2.1 Wastes and Engineered Features

2.1.01 Waste inventories

2.1.01.A Inventory of radionuclides FU2.1

2.1.01.B Inventory of chemically toxic contaminants

Chemotoxicity is out of scope of TURVA-2012.

2.1.02 Waste form materials and characteristics

2.1.02.A Characteristics of used CANDU fuel (UO2)

N.A. Not applicable (different fuel type). Spent fuel characteristics considered by all spent fuel FEPs.

2.1.02.B Characteristics of Zircaloy clad-ding

FU1.4, 3.2.7

2.1.02.C Characteristics of other waste forms (OUT)

N.A.

2.1.02.D Used fuel dissolution 3.2.8, 3.3.1

2.1.02.E Zircaloy cladding dissolution 3.2.7

2.1.03 Container materials and characteristics

2.1.03.A Container design characteristics CA2.4, CA2.6, CA2.7, CA2.8

2.1.03.B Fabrication and installation de-fects

CA1.4 Initial penetrating defect as-sumed in most scenarios.

2.1.03.C Stress corrosion cracking (OUT) 4.2.7

2.1.03.D General or uniform corrosion (OUT)

4.2.5, 4.2.6

2.1.03.E Mechanical degradation 4.2.3

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2.1.03.F Localized corrosion (OUT) 4.2.5, 4.2.6

2.1.03.G Microbial-induced corrosion 4.2.5

2.1.03.H Internal corrosion processes (OUT)

3.2.7

2.1.03 Buffer and backfill materials and characteristics

2.1.03.A Repository layout Repository design is handled elsewhere in TURVA-2012 (e.g. layout designs used by groundwater flow modelling).

2.1.03.B Buffer characteristics and evolu-tion

BU2.3, BU2.4, BU2.5, BU2.6, BU2.7, BU2.8, all Buffer evolution FEPs

2.1.03.C Backfill characteristics and evo-lution

BA2.3, BA2.4, BA2.5, BA2.6, BA2.7, BA2.8, all Backfill evolution FEPs

2.1.05 Seals and grouts (cavern, tun-nel, shaft)

Auxiliary components Grouts injected to the host rock are assumed to be part of auxil-iary components.

2.1.06 Other engineered features (OUT)

Auxiliary components

2.1.07 Mechanical processes and conditions (repository)

2.1.07.A Buffer and backfill swelling 5.2.2, 6.2.2

2.1.07.B Formation and healing of cracks (OUT)

Not specifically but under 5.2.2 and 6.2.2.

2.1.07.C Collapse of repository openings (OUT)

Collapse is not possible after closure (due to backfill). Opera-tional safety is out of the scope of TURVA-2012.

2.1.07.D Evolution of stresses in the near-field

GE2.5, 8.2.2

2.1.07.E Buffer and backfill creep (OUT) Not included due to very low impact (cf. Garisto 2012, p. 134).

2.1.08 Hydrological processes and conditions (repository)

2.1.08.A Desaturation and resaturation of the repository

5.2.2, 5.2.3, 6.2.2, 6.2.3, 6.3.5, 8.3.5

2.1.08.B Groundwater movement 8.3.4, 8.3.5

2.1.08.C Evolution of hydraulic conditions 8.2.6, 8.2.7, 8.3.2, 8.3.4, 8.3.5

2.1.08.D Coupled hydraulic processes (OUT)


2.1.09 Chemical processes and conditions (repository)

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2.1.09.A Water chemistry and evolution (repository)

GE2.10, 8.2.7, 8.3.1

2.1.09.B Hydrothermal alteration (OUT) 5.2.6, 5.2.7, 6.2.5, 6.2.6

2.1.09.C Other chemical processes (OUT)

7.2.1, migration FEPs in almost all compo-nents

2.1.10 Biological processes and conditions (repository)

2.1.10.A Biological processes (repository) (OUT)

5.2.8, 6.2.7, 8.2.10

2.1.10.B Complexation by organics (re-pository materials) (OUT)

5.3.1, 6.3.1

2.1.10.C Biological effects on groundwa-ter movement (OUT)

Considered to have minor ef-fect. Also, neglecting this proc-ess is conservative (cf. Garisto 2012, p. 149).

2.1.11 Thermal processes and conditions (repository)

2.1.11.A Thermal conduction and convec-tion

3.2.3, 4.2.2, 5.2.1, 6.2.1, 8.2.1

2.1.11.B Coupled heat transfer processes (OUT)


2.1.12 Gas sources and effects (reposi-tory) (OUT)

5.3.7, 6.3.7, 8.2.8, 8.3.7

2.1.13 Radiation effects (repository)

2.1.13.A Radiation effects - wasteform 3.2.5, 3.2.6

2.1.13.B Radiation effects - container (OUT)

4.2.1

2.1.13.C Radiation effects - sealing mate-rials (OUT)

5.2.5

2.1.14 Nuclear criticality (OUT) 3.2.11

2.2 Geological Environment

2.2.01 Excavation disturbed zone EDZ considered in groundwater flow modelling variants.

2.2.02 Host rock Geosphere

2.2.03 Other geological units (OUT) N.A.

2.2.04 Discontinuities and lineaments (geosphere)

GE1.2

2.2.05 Contaminant transport path characteristics (geosphere)

2.2.05.A Advection and dispersion 8.3.5

2.2.05.B Diffusion 8.3.4

2.2.05.C Matrix diffusion (OUT) 8.3.4

141

2.2.06 Mechanical processes and con-ditions (geosphere)

8.2.2, 8.2.3, 8.2.4, 8.2.5

2.2.07 Hydrological processes and conditions (geosphere)

8.3.4, 8.3.5

2.2.08 Chemical processes and condi-tions (geosphere)

8.2.7, 8.3.1, 8.3.2, 8.3.3, 8.3.4

2.2.09 Biological processes and condi-tions (geosphere) (OUT)

8.2.10

2.2.10 Thermal processes and condi-tions (geosphere) (OUT)

8.2.1

2.2.11 Gas sources and effects (geo-sphere) (OUT)

8.3.7

2.2.12 Undetected features (geo-sphere)

Out of scope of TURVA-2012.

2.2.13 Geological resources (OUT) Handled elsewhere in TURVA-2012.

2.3 Surface Environment - These FEPs are excluded (not handled individually in this report)

2.4 Human Behaviour - These FEPs are excluded (not handled individually in this report)

3 CONTAMINANT FACTORS

3.1 Contaminant Characteristics

3.1.01 Radioactive decay and ingrowth 3.2.1

3.1.02 Chemical and organic toxin stability

Chemotoxicity is out of the scope of TURVA-2012.

3.1.03 Inorganic solids and solutes Spent fuel

3.1.04 Volatiles and potential for volatil-ity

3.2.9, 3.2.10

3.1.05 Organics and potential for or-ganic forms (OUT)


3.1.06 Noble gases 3.2.10

3.2 Contaminant Release and Migration Factors

3.2.01 Dissolution, precipitation and crystallisation (contaminant)

3.2.01.A Dissolution and precipitation (repository)

3.2.8, 3.3.1, 3.3.2, 4.3.1, 4.3.2, 5.3.1, 5.3.2, 6.3.1, 6.3.2, 8.3.1, 8.3.2

3.2.01.B Dissolution and precipitation (geosphere) (OUT)

8.3.1, 8.3.2

3.2.01.C Dissolution and precipitation (biosphere) (OUT)


3.2.02 Speciation and solubility (contaminant)

142

3.2.02.A Speciation and solubility (reposi-tory)

3.3.1, 4.3.1, 5.3.1, 6.3.1, 8.3.1

3.2.02.B Speciation and solubility (geo-sphere) (OUT)

8.3.1

3.2.02.C Speciation and solubility (bio-sphere) (OUT)


3.2.03 Sorption and desorption (contaminant)

3.2.03.A Sorption/desorption (repository) 3.3.3, 4.3.3, 5.3.3, 6.3.3, 8.3.3

3.2.03.B Sorption/desorption (geosphere) 8.3.3

3.2.03.C Sorption/desorption (biosphere) (Surface environment FEPs not considered here.)

3.2.04 Colloid interactions and trans-port (contaminant)

4.3.6, 5.3.6, 6.3.6, 8.3.6

3.2.05 Complexing agent effects (con-taminant)

3.3.1

3.2.06 Biologically mediated processes, excluding transport (contami-nant) (OUT)

5.2.8, 6.2.7, 8.2.10

3.2.07 Water-mediated transport of contaminants (repository)

3.2.07.A Water-mediated effects (reposi-tory)

4.3.4, 4.3.5, 5.3.4, 5.3.5, 6.3.4, 6.3.5, 7.3.1, 8.3.4, 8.3.5

3.2.07.B Water-mediated effects (geo-sphere)

8.3.4, 8.3.5

3.2.07.C Water-mediated effects (bio-sphere)


3.2.07.D Coupled solute transport proc-esses (OUT)

Not a specific FEP but handled in interaction matrices

3.2.08 Solid-mediated transport of contaminants (OUT)

4.3.6, 5.3.6, 6.3.6, 8.3.6

3.2.09 Gas-mediated transport of con-taminants

4.3.7, 5.3.7, 6.3.7, 8.3.7

3.2.10 Atmospheric transport of con-taminants


3.2.11 Biological-mediated transport of contaminants

4.3.6, 5.2.8, 5.3.6, 6.2.7, 6.3.6, 8.2.10, 8.3.6

3.2.12 Human action mediated trans-port of contaminants


3.2.13 Food chains and uptake of con-taminants


3.3 Exposure Factors - These FEPs are excluded (not handled in this report)

143

Table D-2. Mapping of TURVA-2012 process FEPs to the FEPs in NWMO’s Fourth Case Study FEP list (Garisto 2012, Tables 2.1, 2.2, 2.3). FEPs that were screened out in Garisto (2012) are shown in grey. Surface environment FEPs not included.

FEP number in TURVA-2012

FEP name in TURVA-2012 Mapped to FEP in Garisto (2012)

(FEP number: FEP name)

Process FEPs in the spent nuclear fuel:

3.2.1 Radioactive decay (and in-growth) 3.1.01: Radioactive decay and ingrowth

3.2.2 Heat generation

3.2.3 Heat transfer 2.1.11.A: Thermal conduction and convection

3.2.4 Structural alteration of the fuel pellets


2.1.13.A: Radiation effects – waste form

3.2.6 Radiolysis of the canister water 2.1.13.A: Radiation effects - wasteform


2.1.02.B: Characteristics of Zircaloy cladding 2.1.02.E: Zircaloy cladding dissolution 2.1.03.H: Internal corrosion processes (OUT)

3.2.8 Alteration and dissolution of the fuel matrix 2.1.02.D: Used fuel dissolution 3.2.01.A: Dissolution and precipitation (reposi-tory)


3.1.04: Volatiles and potential for volatility

3.2.10 Production of helium gas 3.1.04: Volatiles and potential for volatility 3.1.06: Noble gases

3.2.11 Criticality 2.1.14: Nuclear criticality (OUT)

3.3.1 Aqueous solubility and speciation 2.1.02.D: Used fuel dissolution 3.2.01.A: Dissolution and precipitation (reposi-tory) 3.2.02.A: Speciation and solubility (repository) 3.2.05: Complexing agent effects (contami-nant)

3.3.2 Precipitation and co-precipitation 3.2.01.A: Dissolution and precipitation (reposi-tory)

3.3.3 Sorption 3.2.03.A: Sorption/desorption (repository)

3.3.4 Diffusion in fuel pellets

Process FEPs in the canister: 4.2.1 Radiation attenuation 2.1.13.B: Radiation effects - container (OUT)

4.2.2 Heat transfer 2.1.11.A: Thermal conduction and convection

4.2.3 Deformation 2.1.03.E: Mechanical degradation

4.2.4 Thermal expansion of the canister

4.2.5 Corrosion of the copper overpack 2.1.03.D: General or uniform corrosion (OUT) 2.1.03.F: Localized corrosion (OUT) 2.1.03.G: Microbial-induced corrosion

4.2.6 Corrosion of the cast iron insert 2.1.03.D: General or uniform corrosion (OUT) 2.1.03.F: Localized corrosion (OUT)

144

4.2.7 Stress corrosion cracking 2.1.03.C: Stress corrosion cracking (OUT)

4.3.1 Aqueous solubility and speciation 2.1.09.C: Other chemical processes (OUT) 3.2.01.A: Dissolution and precipitation (reposi-tory) 3.2.02.A: Speciation and solubility (repository)

4.3.2 Precipitation and co-precipitation 2.1.09.C: Other chemical processes (OUT) 3.2.01.A: Dissolution and precipitation (reposi-tory)

4.3.3 Sorption 2.1.09.C: Other chemical processes (OUT) 3.2.03.A: Sorption/desorption (repository)

4.3.4 Diffusion 2.1.09.C: Other chemical processes (OUT) 3.2.07.A: Water-mediated effects (repository)

4.3.5 Advection 3.2.07.A: Water-mediated effects (repository)

4.3.6 Colloid transport 3.2.04: Colloid interactions and transport (con-taminant) 3.2.08: Solid-mediated transport of contami-nants (OUT) 3.2.11: Biological-mediated transport of con-taminants

4.3.7 Gas transport 3.2.09: 4.3.7, 5.3.7, 6.3.7, 8.3.7

Process FEPs in the buffer: 5.2.1 Heat transfer 2.1.11.A: Thermal conduction and convection

5.2.2 Water uptake and swelling 2.1.07.A: Buffer and backfill swelling 2.1.08.A: Desaturation and resaturation of the repository

5.2.3 Piping and erosion 2.1.08.A: Desaturation and resaturation of the repository


5.2.5 Radiolysis of porewater 2.1.13.C: Radiation effects - sealing materials (OUT)

5.2.6 Montmorillonite transformation 2.1.09.B: Hydrothermal alteration (OUT)

5.2.7 Alteration of accessory minerals 2.1.09.B: Hydrothermal alteration (OUT)

5.2.8 Microbial activity 2.1.10.A: Biological processes (repository) (OUT) 3.2.06: Biologically mediated processes, ex-cluding transport (contaminant) (OUT) 3.2.11: Biological-mediated transport of con-taminants


5.3.1 Aqueous solubility and speciation 2.1.09.C: Other chemical processes (OUT) 2.1.10.B: Complexation by organics (repository materials) (OUT) 3.2.01.A: Dissolution and precipitation (reposi-tory) 3.2.02.A: Speciation and solubility (repository)



5.3.4 Diffusion 2.1.09.C: Other chemical processes (OUT)

145

3.2.07.A: Water-mediated effects (repository)

5.3.5 Advection 3.2.07.A: Water-mediated effects (repository)


5.3.7 Gas transport 2.1.12: Gas sources and effects (repository) (OUT) 3.2.09: Gas-mediated transport of contami-nants

Process FEPs in the tunnel backfill: 6.2.1 Heat transfer 2.1.11.A: Thermal conduction and convection

6.2.2 Water uptake and swelling 2.1.07.A: Buffer and backfill swelling 2.1.08.A: Desaturation and resaturation of the repository

6.2.3 Piping and erosion 2.1.08.A: Desaturation and resaturation of the repository


6.2.5 Montmorillonite transformation 2.1.09.B: Hydrothermal alteration (OUT)

6.2.6 Alteration of accessory minerals 2.1.09.B: Hydrothermal alteration (OUT)

6.2.7 Microbial activity 2.1.10.A: Biological processes (repository) (OUT) 3.2.06: Biologically mediated processes, ex-cluding transport (contaminant) (OUT) 3.2.11: Biological-mediated transport of con-taminants


6.3.1 Aqueous solubility and speciation 2.1.09.C: Other chemical processes (OUT) 2.1.10.B: Complexation by organics (repository materials) (OUT) 3.2.01.A: Dissolution and precipitation (reposi-tory) 3.2.02.A: Speciation and solubility (repository)



6.3.4 Diffusion 2.1.09.C: Other chemical processes (OUT) 3.2.07.A: Water-mediated effects (repository)

6.3.5 Advection 2.1.08.A: Desaturation and resaturation of the repository 3.2.07.A: Water-mediated effects (repository)


6.3.7 Gas transport 2.1.12: Gas sources and effects (repository) (OUT)

146

3.2.09: Gas-mediated transport of contami-nants

Process FEPs in the auxiliary components: 7.2.1 Chemical degradation 2.1.09.C: Other chemical processes (OUT)

7.2.2 Physical degradation


7.3.1 Transport through auxiliary components 2.1.09.C: Other chemical processes (OUT)

3.2.07.A: Water-mediated effects (repository)

Process FEPs in the geosphere:

8.2.1 Heat transfer 2.1.11.A: Thermal conduction and convection 2.2.10: Thermal processes and conditions (geosphere) (OUT)

8.2.2 Stress redistribution 2.1.07.D: Evolution of stresses in the near-field 2.2.06: Mechanical processes and conditions (geosphere)


1.2.02: Deformation (elastic, plastic or brittle) 1.2.03: Seismicity (earthquakes) 2.2.06: Mechanical processes and conditions (geosphere)

8.2.4 Spalling 1.2.02: Deformation (elastic, plastic or brittle) 2.2.06: Mechanical processes and conditions (geosphere)

8.2.5 Creep 1.2.02: Deformation (elastic, plastic or brittle) 2.2.06: Mechanical processes and conditions (geosphere)

8.2.6 Erosion and sedimentation in fractures 2.1.08.C: Evolution of hydraulic conditions

8.2.7 Rock-water interaction

2.1.08.C: Evolution of hydraulic conditions 2.1.09.A: Water chemistry and evolution (re-pository) 2.2.08: Chemical processes and conditions (geosphere)

8.2.8 Methane hydrate formation 2.1.12: Gas sources and effects (repository) (OUT)

8.2.9 Salt exclusion

8.2.10 Microbial activity

2.1.10.A: Biological processes (repository) (OUT) 2.2.09: Biological processes and conditions (geosphere) (OUT) 3.2.06: Biologically mediated processes, ex-cluding transport (contaminant) (OUT) 3.2.11: Biological-mediated transport of con-taminants

8.3.1 Aqueous solubility and speciation

2.1.09.A: Water chemistry and evolution (re-pository) 2.2.08: Chemical processes and conditions (geosphere) 3.2.01.A: Dissolution and precipitation (reposi-tory) 3.2.01.B: Dissolution and precipitation (geo-sphere) (OUT) 3.2.02.A: Speciation and solubility (repository) 3.2.02.B: Speciation and solubility (geosphere) (OUT)

147

8.3.2 Precipitation and co-precipitation

2.1.08.C : Evolution of hydraulic conditions 2.2.08: Chemical processes and conditions (geosphere) 3.2.01.A: Dissolution and precipitation (reposi-tory) 3.2.01.B: Dissolution and precipitation (geo-sphere) (OUT)

8.3.3 Sorption

2.2.08: Chemical processes and conditions (geosphere) 3.2.03.A: Sorption/desorption (repository) 3.2.03.B: Sorption/desorption (geosphere)

8.3.4 Diffusion and matrix diffusion

2.1.08.B : Groundwater movement 2.1.08.C : Evolution of hydraulic conditions 2.2.05.B: Diffusion 2.2.05.C: Matrix diffusion (OUT) 2.2.07: Hydrological processes and conditions (geosphere) 2.2.08: Chemical processes and conditions (geosphere) 3.2.07.A: Water-mediated effects (repository) 3.2.07.B: Water-mediated effects (geosphere)

8.3.5 Groundwater flow and advective transport

1.2.10: Hydrological response to geological changes 2.1.08.A: Desaturation and resaturation of the repository 2.1.08.B : Groundwater movement 2.1.08.C : Evolution of hydraulic conditions 2.2.05.A: Advection and dispersion 2.2.07: Hydrological processes and conditions (geosphere) 3.2.07.A: Water-mediated effects (repository) 3.2.07.B: Water-mediated effects (geosphere)

8.3.6 Colloid transport

3.2.04: Colloid interactions and transport (con-taminant) 3.2.08: Solid-mediated transport of contami-nants (OUT) 3.2.11: Biological-mediated transport of con-taminants

8.3.7 Gas transport

2.1.12: Gas sources and effects (repository) (OUT) 2.2.11: Gas sources and effects (geosphere) (OUT) 3.2.09: Gas-mediated transport of contami-nants

Process FEPs external to the disposal system:

10.2.1 Climate evolution 1.3.01: Global climate change 1.3.02: Local and regional climate change 1.4.01: Human influences on climate

10.2.2 Glaciation 1.2.10: Hydrological response to geological changes 1.3.05: Local glacial effects

10.2.3 Permafrost formation 1.3.04: Periglacial effects

10.2.4 Land uplift and depression 1.2.03: Seismicity (earthquakes) 1.3.05: Local glacial effects

148

10.2.5 Inadvertent human intrusion

0.0.07: Future human action assumptions 1.4.04: Drilling activities (human intrusion) 1.4.05: Mining (human intrusion) (OUT) 1.4.07: Water management (wells, reservoirs, dams)

References

Garisto, F. 2012. Fourth Case Study: Features, Events and Processes. Toronto, Canada: Nuclear Waste Management Organization (NWMO). NWMO TR-2012-14. 302 p.

LIST OF REPORTS

POSIVA-REPORTS 2014

________________________________________________________________________________

POSIVA 2014-01 Sulphide Fluxes and Concentrations in the Spent Nuclear Fuel Repository at Olkiluoto Paul Wersin & Peter Alt-Epping, University of Bern Petteri Pitkänen, Posiva Oy Gabriela Román-Ross, Paolo Trinchero & Jorge Molinero Amphos 21 Paul Smith, SAM Switzerland GmbH Margit Snellman, Saanio & Riekkola Oy André Filby, Brenk Systemplanning GmbH Mirjam Kiczka, Gruner AG

ISBN 978-951-652-239-8 POSIVA 2014-02 Radionuclide transport in the repository near-field and far-field Antti Poteri, Henrik Nordman, Veli-Matti Pulkkanen, VTT Paul Smith, SAM Switzerland GmbH ISBN 978-951-652-240-4 POSIVA 2014-03 Safety Case for the Disposal of Spent Nuclear Fuel at

Olkiluoto – FEP Screening and Processing Posiva Oy ISBN 978-951-652-241-1

safety case for the disposal of spent nuclear fuel at olkiluoto · 2014-04-28 · safety case...

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