RWMC TECHNICAL REPORTRWMC-TRE-04004

Monitoring of Geological Disposal- Current Status and Technical Possibilities -Shinichiro Torata, Keisuke Fukuoka, Takeshi Sugiyama,
Kimitake Yoshimura, Jin Ohuchi, Takao Tsuboya

2005 MarchRadioactive Waste Management Funding and Research Center (RWMC)

This technical paper is to intelligibly compile the R&D report issued by the Radioactive Waste Management
Funding Center (RWMC) under the contract with the Ministry of Economy, Trade and Industry (METI).

FOREWORD

The geological disposal technologies ensure the long-term safety by providing an engineered systemwith sufficient allowance that takes into full account uncertainty of safety assessments and the limits ofreliability of knowledge for the deep geological environment. At the same time, in terms of considering that it
will take long time, or an order of hundred years from planning phase through emplacing and closure ofgeological facilities it is important to strive to improve reliability of geological disposal technologies throughsuch means as: constantly accumulating information and knowledge concerning geological environments;
improving the very latest geological disposal technologies; and reflecting these on the development.
In executing geological disposal, the limits of reliability in applicable technologies should be inconsideration, and then an operation of monitoring considers confirming the required safety performance andthe conditions of the actual geological repositories from the stage of site selection through to a specified timeafter a closure of geological repositories.
The Radioactive Waste Management Funding and Research Center (RWMC) have conducted researchand study regarding monitoring of geological disposal, based on a commission of the Ministry of Economy,
Trade and Industry (METI). Also, RWMC has been undertaking research and study activities through the
hosting of international workshops, and ongoing deliberations by the Advisory Committee for Geological
Disposal Monitoring Systems of RWMC, which is comprised primarily of geological disposal experts.
This report describes a systematic review of studies currently being conducted, including different
approaches and technical possibilities of monitoring for understanding various aspects of HLW geologicalrepositories.

iContent
1.

Introduction..............................................................................................................................................................2
1.1
Background......................................................................................................................................................2
1.2
Objectives and Scope ......................................................................................................................................2
1.3
Background to Post-Closure Monitoring.......................................................................................................3
1.4
Approach to Report .........................................................................................................................................3
1.5
Report Structure...............................................................................................................................................42.

Approaches to Monitoring of Geological Disposal ..............................................................................................5
2.1
Definitions of Monitoring of Geological Disposal........................................................................................5
2.2
Objectives of Monitoring of Geological Disposal.........................................................................................6
2.3
Monitoring and Quality Control of Geological Disposal............................................................................13
2.4
Stakeholders’ Concern to Monitoring ..........................................................................................................13
2.5
Monitoring from Site Selecting Phase to Post-ClosurePhase.....................................................................16
2.6
Considerations of Monitoring Paramters.....................................................................................................18
2.7
Monitoring and Pilot Facilities......................................................................................................................18
2.8
Assessment System of Monitoring Data......................................................................................................20

3.

Technologies for Monitoring of Geological Disposal ...............................................................................21
3.1
Approach to Identifying Monitoring Techniques........................................................................................23
3.2
Measuring Technologies ...............................................................................................................................24
3.3
Transmission Technologies That Use Wireless Underground Communications......................................26

Future Work Programs ...............................................................................................................................................28
Acknowledgements.....................................................................................................................................................28
References.....................................................................................................................................................................29
Attachment A

The Current State of International Discussions Concerning Institutional Control.................. A-1

Attachment B

Survey and Analysis of the status of Monitoring Studies in Japan and Abroad.......................B-1

Attachment C

Record of Workshop on Monitoring...........................................................................................C-1

Attachment D

The Status of Safety Cases and Associated Monitoring ........................................................... D-1

Attachment E

How Safety Cases Are Handled by International Agencies ......................................................E-1

Attachment F

Surveys and Analyses Concerning Underground Research Laboratories (URL) in Japan and
Abroad............................................................................................................................................. F-1i1.

Introduction

1.1

BackgroundThe safety of a geological repository that contains high level radioactive waste must in principle be assured
through passive means, without the premise of any kind of control including monitoring, implemented after
closure for the purpose of assuring long-term safety (OECD/NEA, 1982; IAEA, 1995, etc.). However,recently, a general consensus has been reached that, even though passive safety assurance has been an initialconcept, it is still desirable to prepare various institutional control methods that confirm that safety has being
ensured1. One such method, which has gradually gained widespread acceptance in international studies as animportant way of enhancing public confidence in underground geological disposal, is the implementation ofmonitoring that extends from the early stages of the Repository Site selection process until a specified timeafter the repository has been closed (IAEA, 2001).
The implemental body in Japan, NUMO (the Nuclear Waste Management Organization of Japan), solicited
public opinions concerning the selection of “Preliminary Investigation Areas (PIAs)” related to the geologicaldisposal of vitrified-high-level radioactive waste (HLW) in December 2002. This marked Japan’s entry into
the first preparatory stage of the full-fledged implementation of geological disposal (NUMO, 2002).
Prior to that, in 2000, the Nuclear Safety Commission of Japan (NSC) formulated a basic framework fornational safety regulations designed to facilitate the formulation of policies that are required to ensure thesafety of geological disposal (NSC, 2000). The Commission’s report defined the following measures as “safety
securing principles”: long-term safety securing measures (site selection, engineering measures); and safetyassessment measures, which confirm that safety has been ensured. The report also states that safety should be
confirmed in each stage of disposal operations, including: site selection (selection of Preliminary Investigation
Areas (PIAs), Detailed Investigation Areas (DIAs) and Repository Sites); application for approval to operate;
construction; repository operation; and repository closure. It also states that activities including of monitoringand inspection may be implemented at each stage, from initial siting to the termination of operations.
The Radioactive Waste Management Funding and Research Center (RWMC) have conducted researchand study regarding monitoring of geological disposal, based on a commission of the Ministry of Economy,
Trade and Industry (METI). Also, RWMC has been undertaking research and study activities through the
hosting of international workshops, and ongoing deliberations by the Advisory Committee for Geological
Disposal Monitoring Systems of RWMC, which is comprised primarily of geological disposal experts.
This report describes a systematic review of studies currently being conducted, including different
approaches and technical feasibilities of monitoring for understanding various aspects of HLW geologicalrepositories.

1.2

Objectives and Scope

Implementation policies and plans for monitoring for understanding various aspects of geological repositories
may be in practice formulated by interested parties, including the Japanese government and relatedorganizations and agencies. RWMC’s research have therefore conducted with the following objectives: toextensively survey and summarize information concerning relevant discussions and technologies of various
monitoring addressed in Japan and abroad to date; to formulate an approach to monitoring for understanding orinterpreting various aspects of vitrified-HLW geological repositories after repository closure (named“geological disposal monitoring”) based on those surveys and technologies; to consider technical possibilities
for geological disposal monitoring; and to summarize the outstanding issues.

1See, Attachment A-2-

According to safety assessments of HLW geological disposal, geological repositories are not expected toionize significantly detectable radiation near their engineered barriers or the surrounding geologicalenvironment for a long period after they will have been backfilled, assuming that the waste has been properly
manufactured and the engineered barriers have been properly installed. In this respect, geological disposal
facilities differ from nuclear power facilities or chemical industries that expose the environment to radiation orenvironmentally related substances in certain concentrations.
The long-term safety of geological disposal can be demonstrated by: positing various scenarios related tomulti-barrier systems; performing numerical analyses based on many models and parameters related to thescenarios; and performing safety assessments based on the numerical analyses. However, it has been pointed
out that the analytical results obtained through this procedure entail uncertainty arising from the scenarios,
models and parameters themselves.
In addition, safety assessments show that geological environments that are disturbed by human activities suchas disposal site selection surveys, emplacement of waste, and repository closure, eventually return to their
original state after a given amount of time.
Therefore, geological disposal monitoring is considered to be necessary to be established in terms of reflecting
on the measurement for understanding of the evolutions of repositories environment and geologicalenvironment, while taking into account the effects of human disturbance, as well as confirming that theenvironment is restored to its original state.
At the same time, geological disposal monitoring must be continuously done using methods that do notcompromise the long-term safety of the disposal facility, with technologies that can be used reliably for long
periods over several generations. For example, post-closure monitoring may be required by society because of
the uncertainties in the safety case.
As the foregoing indicates, geological disposal monitoring must be thoroughly studied in terms of whatparameters are measured for how long and by which technologies for understanding or interpreting various
aspects of vitrified-HLW geological repositories after post-closure. Unlike other technical issues associatedwith geological disposal, research on monitoring should therefore be approached from the perspective of the“5W1H” questions: Why (objective); Who; When (from/to); Where; What; and How (methodologies). With
regard to “How” in particular out of “5W1H”, technologies must be developed that can maintain a high degreeof reliability over a long period of time. Therefore, RWMC’s following mid-term aims are specified relations
between objectives of geological disposal monitoring, information for understanding or interpreting various
aspects of vitrified-HLW geological repositories after closure and technologies options available ofmeasurement, then comprehensively summarized them, and systematized that can contribute to the planning ofmonitoring programs by various organizations and agencies.

1.3

Background to Post-Closure Monitoring

Monitoring technologies for geological disposal are defined as one type of “institutional control technology”
since they require institutional support for implementation. Even if the geological disposal itself is a measure toisolate high level radioactive waste without depending on institutional control, it is desirable to actuallymonitor and confirm that the geological disposal facility is providing the predicted and required degree ofsafety. Monitoring in geological disposal is expected to be one of the measures which can meet the societal
demands for additional security.

1.4

Approach to Report

This report describes a systematic review of studies currently being conducted, including different approaches
and technical feasibilities of monitoring for understanding various aspects of HLW geological repositories.

-3-

First, the definition and purposes of monitoring for vitrified-HLW geological disposal are summarized,
followed by a review and summary of discussion points concerning various items related to geologicaldisposal and their relationships to geological disposal monitoring. Then, on the basis of these factors, apreliminary view of geological disposal monitoring is presented, and also some speculations are introduced.
In addition, the studies on monitoring technologies included extensive surveys of current technologies, anexamination of the possibilities of measuring technologies, and a study of transmission technologies used totransmit measurement data from deep underground to the surface. The results of these studies are summarized
and the feasibilities of geological disposal monitoring are discussed and simultaneously outstanding issues are
summarized.

1.5

Report Structure

Section 1 of this report provides the background to this study. Section 2 describes the definition and purposesof monitoring for vitrified-HLW geological disposal (named “geological disposal monitoring”), followed by areview and summary of discussion points concerning various items related to geological disposal and theirrelationships to geological disposal monitoring. Section 3 provides the studies on monitoring technologies
included extensive surveys of current technologies, an examination of the feasibilities of measuring
technologies.

-4-

2.

Approaches to Monitoring of Geological Disposal

As stated in the Introduction, in Japan, “monitoring” is generally used in a sense of such as surveillance,
observation and measurement, which means “monitoring” is used in a wide range of situation. Morespecifically, it can be interpreted as a method of continuously or periodically measuring and observing the statusof a system.
This chapter describes the approaches to geological disposal monitoring that have been explored byinternational authorities and other organizations, and clearly present the results. In carrying out this work, it wasreferred to a wide variety of perspectives, including: discussions on geological disposal monitoring conductedby the Exploratory Committee for Geological Disposal Monitoring Systems; investigations conducted in Japanand abroad2; workshop results3; and surveys of academic experts and specialists.

2.1

Definitions of Monitoring of Geological Disposal

The first task was to examine some existing definitions of monitoring of geological disposal.
Here, definitions of monitoring of geological disposal are summarized through surveys of other countries, aswell as IAEA-TECDOC-1208 (IAEA, 2001).

2.1.1

Definitions in other countries

In 2004, European Commission published a report “Thematic Network on the Role of Monitoring in a Phased
Approach to Geological Disposal of Radioactive Waste” (EC, 2004). In this report, their various considerationsof monitoring including definition, law, plans and techniques by different nations are represented. Thosedefinitions are summarized in Table 2-1 below.

2.1.2

International Atomic Energy Agency (IAEA-TECDOC-1208, IAEA(2001))

IAEA defines monitoring of geological disposal as follows in a technical document on the topic:
For the purpose of the present publication the following definition of monitoring has been employed:
continuous or periodic observations and measurements of engineering, environmental or radiologicalparameters, to help evaluate the behaviour of components of the repository system, or the impacts of therepository and its operation on the environment

2
3

Attachment B
Attachment C-5-

Table 2-1 The definitions of monitoring of geological disposal and the description (EC, 2004)
Country
Definitions
Belgium
Monitoring means the continuous or discrete observing and measuring of the parametersthat help to form an assessment of the behaviour of different components of the disposal
system and/or of the impact of the repository and its operation on the environment.
‘Monitoring’ in this context therefore does not only mean routine checks on operationalsafety.
Finland
Systematic way of collecting and interpreting information from the facility environment withthe objective of detecting possible changes caused by the construction and operation of
the facility in relation to the baseline conditions.
Germany
Continuous or periodic measurements of properties considered important to safety.
SpainContinuous, periodic or sporadic surveillance for the verification of compliance withrequirements and to support the assessment of performance, including data acquisition,interpretation of measures and acceptability contrast
SwedenContinuous or repeated observations or measurements of parameters to increase thescientific understanding of the site and the repository, to show compliance withrequirements or for adaptation of plans in light of the monitoring results.
Switzerland a) Definition used regarding waste management in general“Periodic or continuous determination of the status of parts (or components) of the disposal
system, its environment or of related features (e.g. properties of waste streams, ...) andissues (e.g. alternative waste management options, state-of-the-art in science andtechnology, societal values, view of “affected groups”,...)b) Definition used regarding development of a repository project“Periodic or continuous determination of the status of specific components of the disposal
system by means of appropriate measurements and observations (as opposed to onetime measurements!); the nature of these measurements depend on the geologicalenvironment and the details of the repository concept.”
UK
Measurements of parameters and observations that may have implications for the design
and management of the phased disposal system, for its performance assessment, and forthe development of confidence in the phased disposal system performance and its
assessment.

2.2

Objectives of Monitoring of Geological Disposal

This section summarizes the objectives of monitoring of geological disposal. First, the status of IAEA studies is
described, then it is presented as wide a range of objectives of monitoring of geological disposal as possible,
compiled from the results of surveys conducted with authorities and organizations that are involved with thegeological disposal of high level radioactive waste both in Japan and abroad. Through this approach, it is clearlyshown that there are a great variety of objectives (needs) for monitoring of geological disposal, and so attempt
to organize these diverse monitoring objectives into discrete categories between objectives.

2.2.1

Summary of Objectives Identified by IAEA in IAEA-TECDOC-1208(IAEA, 2001)

I.

To provide information for making management decisions in a stepwise program of repository
construction, operation and closure,II.

To strengthen understanding of some aspects of system behavior used in developing the safety case forthe repository and to allow further testing of models predicting those aspects,

III.

To provide information to give society at large the confidence to take decisions on the major stages of
the repository development program and to strengthen confidence, for as long as society requires, thatthe repository is having no undesirable impacts on human health and the environment,

-6-

IV.

To accumulate an environmental database on the repository site and its surrounding that may be of use
to future decision-makers andV.

To address the requirement to maintain nuclear safeguards, should the repository contain fissile
material such as spent fuel or plutonium-rich waste.

2.2.2

Summary of Objectives of Monitoring of Geological Disposal

Based on objectives in IAEA Report (IAEA, 2001) and other objectives of monitoring by domestic andoverseas authorities and organizations involved in the geological disposal4, with considerations of vitrifiedHLW geological disposal concepts in Japan, objectives of geological disposal monitoring was broadlyclassified as follows:

Objective 1: Confirming safety performance and the adequacy of the repository's engineered measures,
Objective 2: Confirming compliance with statutory requirements,
Objective 3: Providing information for making decisions on policy and operations,Objective 4: Understanding the baseline characteristics of the geological environment at Preliminary
Investigation Areas, etc. andObjective 5: Providing information for public decision-making

Objective 1:

Confirming safety performance and the adequacy of the repository's engineered measures

Viewed from a technical perspective, monitoring provides the basis for confirming that the actual environmentof the disposal system (which constitutes the conditions that lead to safety assessment results) is in fact similar
to the conditions that were predicted through prior analyses, thereby indicating that the system's engineered
measures reflecting on the environment are adequate. One way to confirm the performance that is objectively
evaluated on the basis of the safety assessment is to survey the conditions of the geological environments andengineered barriers. This includes the hydraulic and hydrogeological characteristics surrounding theunderground repository that contains the waste, as well as the heat, hydraulic, stress and hydrogeochemical
characteristics surrounding the waste itself.
The period for monitoring changes in these characteristics needs to be studied while taking into account suchfactors as the uncertainty that was previously described. For example, if monitoring were continued for several
decades or a century after the repository is closed (equivalent to the duration that hydraulic recharging of theunderground facilities is expected to take), it could still yield valuable information for understanding how safety
can be assured in the future.
It is also essential to obtain environmental baseline data (including groundwater levels) before the environment
is disturbed by repository construction, etc., so that comparisons can be made with groundwater levels after a
closure of repository.

1)

Confirming the functionality of disposal system components

4

Attachment B-7-

The overpack, buffer materials, rock mass, and other components of the disposal system must be checked
to confirm that their functions are working as expected. Also, the following should be confirmed: that thevalues that are obtained through indoor tests of the physical properties of engineered barriers and othercomponents are the same as those obtained in actual construction environments, and that the predictions
that were analytically projected on the basis of those values, were in fact appropriate for such major
evaluative parameters as physical properties (including stress-buffering function and rises in temperature)and chemical properties (related to corrosion and water quality).

2)

Confirming values established for design and construction
The cavity is designed under the assumption that the physical properties of the rock mass and the tectonic
stress are either uniform or variable In actual practice however, some rock masses have non-uniform
properties that generate great spatial fluctuations. Similarly, such factors as the amount of sump water,
geothermal gradient, and the amount of groundwater recharge should be taken into consideration in thedesign, based on survey results. To demonstrate the reliability of a geological disposal system, it isimportant to show how much tolerance has been built into the conservative design values that have been
set as described above. The design and construction assumptions must be tested and confirmed during therepository's development phase.

3)

Verifying safety assessment models
Verification is done to check whether model structures and the physical and chemical quantities used ineach model are properly set in terms of: i) rock mass crack network models and creep models, which areformulated as part of system safety assessments based on groundwater scenarios; and ii) redox potential,
pH, and other parameters of each model. These also include the boundary conditions of the safetyassessment models, including wide-area hydraulic gradient distribution and the characteristics ofEDZ(Excavation Disturbed Zone).

4)

Making decisions concerning improvements or repairs in the operation and construction of therepository
Feedback data should be obtained for assessing improvements in engineering policies such as the selectionof excavation, drainage, and ventilation methods, as well as safety measures in case of earthquakes or
accidents. Also, if the quality of supports, overpack, buffer materials, etc., is found out to have deteriorated
for any reason, repair work may be necessary. To decide whether or not to perform repairs, it is importantto establish various criteria levels or values. Canada has adopted this approach by setting: i) allowablelevels or values to be used as criteria for determining whether or not to conduct a detailed investigation;and ii) emergency limit values that indicate repairs must be conducted immediately (Simmons et al.,1994).

Objective 2:

Confirming Compliance with Statutory Requirements

Many countries use a phased approach in their geological disposal projects. The entire project process is divided
into multiple phases, beginning with site investigation from the ground surface through to final closure of thedisposal repository. When proceeding from one step to the next, it may be necessary for the disposal
implementing entity to obtain safety confirmation or permission from a safety regulator. In such a case, theentity would be expected to draw up or modify application forms in accordance with notifications, technicalstandards, etc. issued by the regulator as criteria for judging whether or not confirmation/permission should begiven, while taking into account monitoring information.
A large amount of monitoring data and quality management records are generated to achieve Objective 1 above(confirming the functionality of disposal system components). From among that information, the mostimportant data and reference values are generally adopted as requirements by the regulator and are reflected inlaws and regulations.

-8-During the construction and operation of the repository, it may be necessary to implement monitoring for thefollowing purposes: to measure and observe radiation and other parameters to the same degree as is done at
nuclear power plants to ensure the safety of facility workers and local residents; and to ensure compliance withgeneral safety monitoring and regulatory criteria concerning the environment, including water quality.
1)

Post-closure statutory requirements
Japan still needs to formulate safety regulations that apply to geological disposal monitoring. In the US,
the Environmental Protection Agency (EPA) stipulated general radiation protection standards in its 40
CFR Part 191 (EPA, 1993). To ensure compliance with this document, the EPA subsequently establisheddetailed, long-term monitoring requirements for Waste Isolation Pilot Plant (WIPP) sites in its 40 CFRPart 194 (EPA, 1996). In accordance with this latter document, the US Department of Energy (DOE) has
selected pre/post-closure monitoring parameters for WIPP that are called Compliance Monitoring
Parameters (COMP). These were derived from sensitivity analyses based on the Evaluation of the
Applicability of Biosphere-Related Features, Events, and Processes (FEP) or related scenarios. Thus,
monitoring plays a role in post-closure safety regulations that are specific to geological disposal.

2)

Statutory requirements applied to construction and operations (safety of workers and local residents)
In many countries, safety regulators require monitoring not only to ensure technical reliability but also tocheck radiation amounts to ensure the safety of workers and local residents during construction andoperation. The purposes of this type of monitoring are classified as follows.

3)-

Monitoring radiological effects on facility workers and the public during repository operation incompliance with legal regulatory requirements, as is the case with ordinary nuclear facilities,-

Monitoring non-radiological effects on the environment surrounding the repository during
operation, in compliance with legal regulatory requirements for the environment concerning waterflowing into water sources or changes in water quality resulting from excavation or construction
work and-Confirming compliance with the safety requirements applied to the underground facilities of general,
non-nuclear industries with regard to such factors as dust, gases, and noise.

Statutory requirements related to environmental impact
In many countries, regulators require monitoring for the purpose of assessing environmental impact. Manyof the monitoring items in this category overlap with those in the category of monitoring to obtain abaseline.

Objective 3:

Providing Information for Making Decisions on Policy and Operations

The implementor may use monitoring to facilitate operations and modify plans at each stage of repository
development in ways that are distinct from the technical concerns of Objective 1 and the statutory concerns of
Objective 2. Specifically, monitoring data and assessment results might be used for revising written materials
that explain site safety, or for obtaining basic data for design changes.
In ordinary tunnel construction, it is common to adopt a flexible approach (often referred to as "reversibility" or"design as you go") to accommodate the uncertainty of information about the geological environment. Designand construction methods are modified freely based on information about the actual geological environmentthat is obtained as construction proceeds. Likewise, for geological disposal programs involving long-term
safety, it is not reasonable to specify every design condition necessary for repository construction or theemplacement of waste before construction and operation begin. In practice, construction and operation-9-

programs will be pursued on the basis of design parameters. If monitoring provides in-situ data that differs fromdesign assumptions, design or construction methods can be flexibly modified accordingly.
1)

Providing information for public decision-making
In recent years, Japan, Europe and the US have tended to adopt a phased approach to geological disposal
projects. Phased policies are being adopted not only because of the extremely long-term nature of the
projects, but also because they permit reversibility as a project is implemented, thereby providing one way
to enhance public confidence in disposal operations. Stages encompassed by the early phase of a project
include the phased selection of the site for final disposal facilities, and changes in design. Further stages areencountered as the project progresses, including repository construction, operation, and closure. In thesafety case defined by IAEA (see Attachments D and E), allowance is made for unsolved problems which
may emerge in each phase of project development, and decision-making (including policies to solve suchproblems) can be implemented in a subsequent phase. Geological disposal monitoring will play a criticalrole in the decisions made by project operators in each phase, including: i) whether or not to proceed fromthe construction phase to the operation phase; ii) how waste emplacement should be implemented indifferent phases over the course of several decades; iii) how emplaced waste should be retrieved(described later); and iv) whether or not to proceed to the disposal/access tunnel closure phase after
operations have been terminated. SKB is planning to implement preparatory emplacement prior to fullscale emplacement, and monitoring will be used to help decide when to proceed from the former to thelatter (see Attachment B).

2)

Retrievability of emplaced waste
Retrievability, which means being able to recover emplaced waste, is an important concept that merits
study from a broad perspective in implementation policies designed to bring greater flexibility togeological disposal (OECD/NEA, 2001).
France and the US are good examples of countries that have identified the retrievability of emplaced waste
either as a national necessity or as a policy of the implementing entity (EPA, 1993; ANDRA, 1991). The
French believe that there is a close relationship between retrievability and geological disposal monitoring,in that active monitoring of such factors as the degree of waste constriction resulting from rock mass creep,or the corrosive environment surrounding the waste, can help to guarantee retrievability.

Objective 4:

Understanding the Baseline Characteristics of the Geological Environment at Preliminary
Investigation Areas, etc.

"Understanding the baseline" means measuring the characteristics of the geological environment of the final
disposal site before it has been disturbed by such activities as boring surveys conducted from the ground surface(which are done when selecting a repository site) or disposal facility construction. Baseline information can
provide useful parameters for confirming repository performance or implementing engineering measures, andmuch of it overlaps with monitoring carried out for Objective 1.
From the perspective of society, one of the purposes of geological disposal monitoring cited under Objective 5
is "Compiling databases for future generations." Baseline information, which records initial environmental
conditions, is an important component that should be recorded in these databases.
Baseline information on the characteristics of the geological environment might also be necessary to ensure
statutory compliance as described in Objective 2. Therefore, an understanding of the baseline characteristics of
the Preliminary Investigation Areas will be crucial as a source of fundamental information for implementing
geological disposal programs.

- 10 -

1)

Understanding baseline characteristics of geological environments
An understanding of the baseline characteristics of geological environments (such as undergroundhydraulic and hydrogeochemical properties) can help to clarify the environmental impact of a repository
project. It can also be important as a means of tracing geological environmental information while taking
into account the expanse of space extending from the ground surface to deep underground, as well as long
periods of time.
According to the results of surveys conducted overseas, nearly all advanced countries have implemented
or intend to implement policies designed to obtain an understanding of the baseline characteristics ofgeological environments. As already noted, geological disposal projects involve the selection of repository
sites in phases. An understanding of the baseline is expected to be needed during the initial survey phase,before activities such as boring down from the ground surface unavoidably disturb the geologicalenvironment.

Objective 5:

Providing Information for Public Decision-Making

Geological disposal monitoring that falls under this category can be further divided into two purposes: i)providing technical information concerning geological disposal necessary to public decision-making, which isthe present generation’s needs ; and ii) compiling databases to help future generations make decisions.
As noted previously, monitoring that is implemented in connection with waste retrievability or the phased
implementation of disposal operations plays a role in providing technical information oriented toward publicdecision-making.
In Switzerland, EKRA (EKRA, 2000) has adopted the following geological disposal concept that depends onlong-term monitoring.: Before the repository is closed, information is collected on the performance of its
various disposal systems and on the characteristics of the geological environment surrounding it. After public
acceptance is obtained concerning the safety of the said geological disposal systems, the repository is closed. In
this concept, monitoring is used to collect data and confirm repository performance until closure.
1)

Enhancing the confidence of the public, including local residents with regard to geological disposal
Information, based on actual measurements, that testifies to the safety of a geological disposal system canenhance the confidence of the public (particularly local residents) with regard to disposal site operations. Ina public dialog that contributes to public decision-making through Public Involvement (PI), specificgeological disposal monitoring items might be discussed that are both feasible and helpful in promoting
public peace of mind.

2)

Compiling databases for future generations
IAEA is currently considering another objective for geological disposal monitoring: compilingenvironmental data at and around repository sites which might contribute to future decision-makers.

As discussed above, it turned out that monitoring of geological disposal has many functions corresponding to awide range of objectives. Those objectives are summarized in Table 2-2 below.

- 11 -

Table 2-2 The objective of monitoring of geological disposal and the description
Objective
1.

2.

Description

Confirming safety performanceand the adequacy of therepository's engineered measures♦

Confirming compliance withstatutory requirements

♦

♦
♦
♦

♦
♦

3.

Providing information for making
decisions on policy and operations

♦
♦

4.

Understanding the baselinecharacteristics of the geologicalenvironment at Preliminary
Investigation Areas, etc.
Providing information for publicdecision-making

♦

5.

♦
♦

Confirming whether or not disposal systemcomponents function as planned
Confirming design/construction assumptions
Verifying safety assessment models
Judging the need for facility improvements or
repairs related to repository
operation/construction
Confirming compliance with regulations after a
closure of repository
Confirming compliance with safety regulations
for workers and local residents during
construction and operation
Confirming compliance with environmental
impact assessment regulations
Providing information for decision-making
Dealing with the retrievability of emplaced waste
packages
Clarifying the baseline characteristics of thegeological environment

Enhancing the confidence that the public(particularly local residents) have in geologicaldisposalCompiling databases for future generations

The objectives for geological monitoring listed above can be correlated with each other as described below.
Objective 1 (Confirming safety performance and the adequacy of the repository's engineered measures) andObjective 2 (Confirming compliance with statutory requirements) have comparatively clear-cut measurementtargets and assessment methods. The information related to these two objectives will be actively utilized as the
project proceeds.
In contrast, Objective 3 (Providing information for making decisions on policy and operations) involves
information to help project operators and policy-makers make decisions based on such factors as the progress of
future geological disposal programs, the different circumstances surrounding geological disposal, theadvancement of geological disposal technologies, and public acceptance.
Objective 4 (Understanding the baseline characteristics of the geological environment at Preliminary
Investigation Areas, etc.) can be thought of as covering the collection of fundamental data to meet diverse
requirements, including the objectives and assessments described in Objectives 1, 2, and 3. For geologicaldisposal that involves the postulation of extremely long periods of time, monitoring in this category is alsomeant to ensure the traceability of geological environmental information, both spatially between the surface anddeep underground, and temporally over extended periods.

Objective 5 (Providing information for public decision-making) seems to overlap extensively with the otherobjectives. What distinguishes it, however, is that it enables the determination of monitoring parameters thatshould be measured on the basis of full discussion and public decision-making when the time comes to select a
final disposal site.

- 12 -

2.3

Monitoring and Quality Control of Geological Disposal

Quality control is critical to defining quality-related policies, objectives, and responsibilities that are directly
related to the safety of a multi-barrier system, as well as ensuring that the components comprising the disposal
system are functioning at their targeted level.
Quality control related to repository construction and operation is likely to be modeled on quality control caseexamples that have been applied to conventional industries in accordance with Japanese Industrial Standard(JIS) and other regulations5, with the aim of aggressively securing the prescribed system performance(including safety).
Plans for the quality control system described above will be formulated more specifically as part of a geologicaldisposal project plan.
Although geological disposal monitoring overlaps with quality control to some extent, its main focus is on
monitoring the system's status after the repository has been closed, which is a unique characteristic of geologicaldisposal. Unlike quality control, therefore, monitoring is not aimed at actively securing prescribed performancefrom engineered or natural barriers.
The repository can be viewed as a product, in which sense measurement confirmations can be likened tocompletion checks that must be carried out through the various stages of construction, operation, and final
closure. These measurement confirmations are distinct from geological disposal monitoring, and their details
will probably be examined and finalized systematically based upon quality control and related plans.
A repository is completed as a system when it is closed. Prior to closure, long-term system behaviors areanalyzed and predicted through safety assessments. The purpose of subsequent geological disposal monitoringis to confirm, through the acquisition of data directly related to various assessment parameters, that the actual
behavior of the repository conforms to analytical predictions. Because analytical predictions involve both
temporal and spatial uncertainties, the above-mentioned monitoring data provides a means for confirming thatthe repository's post-closure behavior does not greatly deviate from the scope of the analytical predictions.
Should such a deviation occur, the data can be used to compare changes over time with analytical predictions,
thereby clarifying the repository's post-closure behavior.
As described above, there is a difference between quality control and monitoring. Quality control involves
confirmation testing to ensure prescribed quality and system performance before the repository is closed.
Monitoring, on the other hand, is primarily concerned with understanding repository conditions after closure,although it also comes into play in pre-closure stages as a means of obtaining initial baseline values for tracking
long-term changes over time. Because of this difference, the approach to which the agencies that plan andexecute these two distinct activities are not necessarily the same as those they take to the technology to apply. Inview of this, the systems and technologies used for quality control and monitoring must be developed
separately.

2.4

Stakeholders’ Concern to Monitoring

Table 2-3 summarizes how stakeholders6 in monitoring of geological disposal, such as the disposal project
implementing organization, safety regulatory authority , and society (the general public and the peer reviewers
are expected to relate to the objectives of geological disposal monitoring as described in section 2.2.2 above.
5

6

Ex. JIS Z 9904/ISO 9904: Control of quality means every activity to set out quality policy, quality objectives andresponsibilities, and to carry out quality plans, quality control (in the narrow sense), quality assurance andimprovements in quality system
The workshop report (OECD/NEA, 2000) states in its preface that stakeholders include waste generators, waste
management agencies, safety regulators, potential host communities, elected representatives, and technicalintermediaries between the public and decision-makers.

- 13 -

2.4.1

Disposal project implementing organization

Disposal project implementing organizations are likely to implement different kinds of monitoring geared
toward all five objectives shown in Table 2-2. Monitoring for Objective 1 of monitoring is particularly
important for presenting an enhanced safety case. Objective 2 of monitoring is for the responsibility of
project implementing organization, who will likely use monitoring information in order to prove that therequirements are met which are set by safety regulatory authority. Objectives 3 of monitoring would prove
to be useful for gathering appropriate decision-making data for such purposes as project improvement andrationalization. For Objective 4, monitoring could be used to confirm geological environmental conditions,while for Objective 5 it could provide clear corroborative information related to the phased
implementation process of the repository (site selection, construction, operation, closure, etc.), and help topromote dialog with the general public through the preparation of post-closure monitoring and otheroptions.

2.4.2

Safety Regulatory Authority

DOE Waste Isolation Pilot Plant (WIPP) in the US is the only example in the world in which detailed
statutory requirements regarding geological disposal monitoring are established; other countries are still
studying the issue. Generally speaking, Safety Regulatory Authority will not require disposal implementing
organization to confirm their technical compliance with statutory standards until the statutory
requirements concerning geological disposal monitoring have been established.
In WIPP's case, the Department of Energy (DOE), which is the operator, developed a Compliance
Monitoring Program (CMP) to support its performance confirmation programs for the purpose ofsatisfying the monitoring requirements established by the Environmental Protection Agency (EPA). As
part of that effort, the DOE selected 10 Compliance Monitoring Parameters (COMP). The DOE isrequired to submit a compliance confirmation application to the EPA every five years.
Regarding Objective 2, requirements in other objectives might be included in laws and regulations.
Objective 2 is mainly related to laws and regulations, while other Objectives are somewhat related to laws
and regulations.

2.4.3

Society (General Public and Engineers)

In general, residents living near a candidate site want confirmation that the repository will be safe
especially both for themselves and for their children and grandchildren. The policy that implementing
organizations adopt in response to this is an important element in the residents' decision-making process.
Therefore, public confidence in the way the implementing organization implements the disposal process isa key concern, as is the geological disposal monitoring that includes parameters selected under Objective
3, which includes such options as post-closure monitoring. In addition, the peer reviewers who act asintermediaries between the general public and decision-makers will probably show their concern with all
five objectives.

- 14 -

- 15 -

Monitoring objectives

Stakeholders

Table 2-3 Relationships between Monitoring Objectives and Stakeholders
Disposal project Implementing
Safety Regulatory
Society (public and technical intermediaries)
Organizations
Authority

1.

Confirming safety performanceand the adequacy of therepository's engineered measures

Enhancing safety case2.

Confirming compliance withstatutory requirements

Reporting to regulators

3.

Providing information for making
decisions on policy andoperations

Demonstrating the process ofphased implementation andcorroboration; dialogue withpublicReview by engineers
Participation by administrators and policymakers

4.

Understanding the baselinecharacteristics of the geologicalenvironment at Preliminary
Investigation Areas, etc.

Improving and rationalizing
project; Dealing with defects, inany defects

Review by engineers

5.

Providing information for publicdecision-making

Confirming phased
implementation

Public decision-making

Review by engineers

Judging the items
shown at left column

Review by engineers2.5

Monitoring from Site Selecting Phase to Post-Closure Phase

In recent years, many countries have tended to favor making decisions in each operational phase to ensuretechnical and public flexibility in geological disposal projects (e.g., OECD, 2001). Table 2-4 correlates theobjectives of geological disposal monitoring with each project phase to examine the role which monitoring
plays in each phase.

2.5.1

Disposal site selection phase

Monitoring will provide information that:-

Is important for meeting safety regulations; for making policy decisions concerning repository siting
and the initiation of construction; and for facilitating public decision-making concerning siting,-Will be needed by implementing organizations to develop appropriate safety cases for disposal
systems, based on an understanding of the baseline characteristics of the site environment and-Will provide information needed in both technical and social contexts, based on data on trends in thelong-term conditions of the geological environment extending beyond closure; the impact of therepository before and after installation; and the trends of recovery in the geological environment
after closure.

2.5.2

Construction, operation, and closure phases

Monitoring will provide:-

Data concerning engineered measures and safety performance that meet safety regulations and-Information that contributes to phased project development and public decision-making.

2.5.3

Post-closure phase

Because geological disposal systems are not expected to require active safety control, monitoring is
expected to:-Provide an understanding of recovery and stabilization trends in the geological environment
surrounding the repository, after baseline characteristics have been determined and-Contribute to waste retrieval and to the provision of post-closure information needed by society.

- 16 -

- 17 -

Monitoring objectives

Project phase
2. Confirming compliance withstatutory requirements
1. Confirming safety
performance and theadequacy of therepository's
engineered measures
3. Providing information
for making decisions
on policy andoperations
4. Understanding thebaselinecharacteristics of thegeologicalenvironment at
Preliminary
Investigation Areas,etc.
5. Providing information for publicdecision-making

Table 2-4 Roles of Monitoring in Each Project Phase
Determination of
Selection of disposal site
Construction / operation
closure/closure
Regulatory requirements
Regulatory requirements
Regulatory requirements
for approval
for construction/operation for closure
Not applicable
Applicable (Regulatory
Applicable (Regulatory
requirements)
requirements)

Post-closure
Not applicableNot applicable

Applicable (Siting
decisions)Applicable (Phased
project development)

Applicable (Determining
repository closure)

Not applicable

Applicable (Prior baseline
data)Applicable (Sitedisturbance caused byproject implementation)

Applicable

Applicable(Restoration/stabilization
after repository closure)Public decision-making
about siting

Confidence in disposal
project

Public decision-making
about repository closure

Monitoring continues aslong as society requires

2.6

Considerations of Monitoring Parameters

In view of the monitoring objectives summarized above, geological disposal monitoring must be directed
toward the engineered components composing of engineered barriers and repositories, surrounding
environmental conditions, and far-field as the structural components of natural barriers.
It is particularly important to recognize that the act of monitoring itself provides a pathway by whichradionuclides migrating from the waste packages can pass through engineered and natural barriers. In view ofthis, consideration should first be given to the factors presented in Figure 2.1, which are considered to be thestandard scenario for evaluating long-term repository behavior.
Concerning near-field performance, major factors include the behavior of the waste packages and buffermaterials, as well as the environment of surrounding rock mass that exerts an influence on them. Because thesefactors also relate to discussions on waste retrievability, they are likely to draw the attention of stakeholders. It
must be kept in mind, however, that direct monitoring of these factors would entail much equipment to beinstalled, which would ultimately have a negative impact on barrier performance.
The assessment of far-field performance can provide corroborating information to demonstrate that theconditions in which the repository has been placed are appropriate. Specifically, this means such things asascertaining that the groundwater is in a reducing environment and is flowing slowly, and that the deep
geological environment is stable. To meet such requirements, it is important to conduct technical reviews with afocus on implementing the necessary long-term monitoring.
Technical approaches to geological disposal monitoring will be discussed in Chapter 3.

2.7

Monitoring and Pilot Facilities

Directly accessing the waste packages for the purpose of monitoring could negatively affect the long-term
performance of engineered barriers. One way to solve this problem is to build a pilot facility at another site set
apart from the actual disposal site and implement monitoring there (IAEA, 2001).
The pilot facility proposed by EKRA of Switzerland (see Attachment B) is a small-scale facility to beconstructed before waste packages are emplaced in the main underground disposal facility. A small amount ofwaste packages, fitted with monitoring equipment to confirm safety, will be emplaced in the pilot facility, andno monitoring will be implemented in the main facility itself. The pilot facility will remain in use even after themain facility begins operating.

- 18 -

- 19 Figure 2.1 Reference Case for Performance assessment of geological disposal (JNC, 1999)

2.8

Assessment System of Monitoring Data

RWMC held an international workshop in February 2002 (see Attachment C), where the following questions
were raised: What should be done if the data obtained through monitoring deviates from the scope of behavior
initially expected? To assess the data obtained through monitoring, it is important to correctly correlate themeasured values obtained through monitoring with the assessment tools needed to understand the data. To
illustrate this, the concept of trigger values as applied at WIPP of the US is presented below, based on apresentation given at the workshop.

WIPP trigger values
Trigger values mean the upper and/or lower limit of monitoring data of the WIPP. Those values are thevoluntary standards set by the implementor (the U.S. Department of Energy) in order to investigate the causesof the appearance of unexpected values in monitoring, if any, and assess whether or not there exists any effecton regulation compliance. In some cases, different measures may, if necessary, be taken depending on assessed
results; in other cases, simply modifying the trigger values would be enough. The trigger values are not given tosome monitoring parameters, which cannot precisely represent the long-term performance of a repository.
Although the EPA does not make it compulsory to apply such a system to pre/post-closure monitoring
programs, the DOE considers the trigger value the most important part of the entire monitoring program. The
DOE has gone through the following five steps in order to extract trigger values for each monitoring
parameter:First step: Transparency in data properties of monitoring (e.g., measured values, observed values, notified
values, etc.)
Second step: Mapping the monitoring-related data to performance assessment factors (performanceassessment parameters, FEP deterministic grounds, conceptual models, etc.)
Third step: Transparency in the data of the parameters, which were used for proving performance assessment
in association with application for compliance confirmation
Fourth step: Transparency in the effect, which may be exerted on disposal system performances by variations
in performance assessment factors
Fifth step: Decision on whether or not to give trigger values (by experts in charge of performance assessment
studies). If yes, trigger values are set as the monitoring parameter and monitoring data, or either of the two.
The DOE has given trigger values to seven out of ten compliance monitoring parameters set in the WIPP.

In view of the example presented above, it appears that the standardization of the following items may be a keytask in establishing a monitoring-related measurement/assessment system:-

Methods of collecting data,-

Methods of evaluating data and-Methods and criteria for making decisions (expert judgments)- 20 -

3.

Technologies for Monitoring of Geological Disposal

The technologies used for monitoring of geological disposal should be developed while taking into
consideration the diverse monitoring objectives summarized in Chapter 2. Also, as already noted, thedifferent roles and objectives of implementing organization, safety regulators, local governments,and other interested parties should be taken into account when monitoring is implemented. These
many different objectives (needs) should be accommodated when monitoring is implemented in the
future.
With this in mind, it was determined to initiate the development of monitoring technologies for the
purpose of preparing a "technology menu" in additional further studies that breaks down thedevelopment of monitoring technologies into categories by asking the so-called "5W1H" questions:
Why (objective); Who; When (from/to); Where; What; and How (methodology) in order to develop
monitoring plans. This approach increases the flexibility in the monitoring programs of different
agencies as monitoring technologies are developed. The investigative methodologies which lead todeveloping monitoring plans are shown in Figure 3.1.
From the site selection through to the construction and operation phases of a disposal project,measuring equipment can be accessed relatively easily through open boreholes and survey tunnels.
This means that most of the existing measuring technologies and methods would be able to be used
to implement monitoring of geological disposal. What is more important, however, is forecasting theapplicability of technologies slated for use after the repository has been closed, when access to therepository and monitoring equipment will be severely restricted. The technology menu forgeological disposal monitoring therefore would be to list technologies that are highly stable andreliable over an extended period of time. They would be prepared for confirming that a repository is
operating safely even after repository closure, which can be considered the most important anduniquely characteristic feature of geological disposal.
A goal is to create a specific and appropriate menu based on the technical characteristics ofgeological monitoring, with obtaining knowledge through an examination of case studies andtechnical surveys. It is focused on measuring technologies (sensors) and wireless transmission
technologies that could be applied to the geological disposal in this study.

- 21 -

Figure 3.1 Flowchart related to the Development of Monitoring Plans- 22 -

3.1

Approach to Identifying Monitoring Techniques

With the exception of measurements taken near the ground surface, most technologies for geologicaldisposal monitoring must be developed while taking into account the environmental conditions formeasurement shown in Table 3-1.

Table 3-1

Environmental Conditions for Measurement to be Considered for Geological Disposal
Monitoring
Items
Near fields of the waste package
Far fields of the waste package
Temperature
100 °C max.
45 °C (depth of 1000 m) *Pressure
11 MPa** (depth of 1000 m)
10 MPa** (depth of 1000 m)
Water quality
Salt water/Fresh water
Saline water/Fresh water-0
3X10 mGy/h (gamma ray)
Radiation***−
3X10-2 mGy/h (neutron radiation)*
JNC (2000)** It is assumed that swelling pressure (1 MPa) of buffer materials is added to hydrostatic pressure (10MPa) at a depth of 1000 m .
*** The value on the overpack surface when the thickness of overpack is 190 mm (JNC, 2000)

In attempting to clarify the technical issues involved with geological disposal monitoring, it isnecessary to consider factors and methodologies such as the following from among the 5W1H
questions which would be indicated in the technology menu: time (when measurement is started,
how long it lasts, how often it is conducted, and when it is terminated); place (two-dimensional
space on the ground surface, and depth); how the system of the measuring equipment is maintained;
and whether or not the equipment can be replaced.
The results of survey conducted up to now indicate that studies should be conducted on existing
technologies that can be applied to geological disposal monitoring, and that the following two issues
are considered as worth undertaking for possible monitoring parameters :-Monitoring hydraulic and hydrogeochemical properties and-Developing wireless underground communication technologies

The above two issues were selected for the following reasons.
Safety evaluation scenarios for the disposal of high level radioactive waste (as referred to in thereference case included in the H12 Report (JNC, 1999) and shown in Figure 2.1 in Chapter 2 above)
indicate that the action of groundwater could dissolve radionuclides contained in the waste packages
and transport them through geological strata (natural barriers) to the ground surface where people
live. Therefore, it has been placed priority on the development of monitoring that measures hydraulicand hydrogeochemical properties so that technical forecasts can be made. Wireless undergroundcommunications technology will be a common component of many monitoring technologies as ameans of transmitting to the ground surface measurement data that is obtained deep underground.
Because it does not use cables to transmit data from the sensors, wireless technology offers apromising way to implement monitoring without compromising the performance of the repository
after closure.

- 23 -

3.2

Measuring Technologies

Surveys were conducted on the content of measurements being taken at deep underground researchlaboratories (URLs) and other facilities in Japan and abroad in connection with geological disposal(see Attachment F).
The chemical properties of groundwater, particularly its oxidation-reduction potential (Eh) and its
hydrogen-ion concentration (pH), are closely related to the physical movement of radionuclides andare therefore important parameters to measure. In studies on monitoring, these measuring
technologies are among the first that should be addressed. In URLs in Japan and abroad, it was
found no example of continuous measurements except measurements made of sampled groundwater.
Concerning Eh, a survey of currently available equipment, for clarifying oxidation-reduction
environments has clarified no equipment for continuous monitoring of oxidation-reduction
environments deep underground over long periods of time. A similar situation was found with regard
to pH. There are two methods in general use to measure pH: electrical measurement, andmeasurement through color comparison. It was studied on various measuring devices that utilize
these two methods to determine their applicability to disposal environments in terms of such factors
as temperature, pressure/shock, oxidation-reduction ambience, degree of contact between sensors
and water, radiation, and long-term characteristics. As the devices used to measure both Eh and pH
rely in principle on chemical reactions for detection, they are ill-suited to long-term, continuous
monitoring, and this gives rise to a technical need to calibrate the equipment to accommodate theenvironment in which it will be used, to change the materials used, and to develop ways to protect
against deterioration. Therefore, the scope of survey has been broadened to investigate technologies
that are similar to the systems that have been developed for understanding oxidation-reduction
environments deep underground, such as the sensor technology used in the Shinkai 2000 manned
research submersible, or in space exploration and development, or in the medical field, wherecompact, energy-efficient technologies are found.
Also, one of the latest trends in measurement technology is sensors combined with fiber optics,
which are increasingly being used to measure factors such as chemistry, temperature, anddeformation. Then, surveys of the measurement principles and sensor performance of these latest
technologies are being conducted and ways to apply them to geological disposal monitoring arebeing studied.
The current status of trends in sensor technology is presented in Table 3-2 below for the measured
parameters that are expected to be relevant to geological disposal monitoring.

- 24 -

Table 3-2

Trends in Sensor Technology for Different Measured Parameters- 25 -

Measurement category

Measured items

Measurement method

Issues raised in discussions of technologies
for monitoring of geological disposal

Heat

Temperature

Thermoelectric measurement

Because the measuring device uses
electrically conductive metal, it is subject tochange and deterioration in the environment.

Groundwater

Water level; pore waterand moisture content

Water-level gauge; moisture meter

The long-term reliability of chemical methods
and electrical methods (measurement ofelectrical conductivity) is an issue.

StressRock pressure;fractures; displacementand deformation

Acoustic emissions (AE); distortion /displacement gauge

Supplying power to acoustic emission
transmitters and receivers

Chemistry

Water-quality chemistry
Dissolved component

Eh / pH measurement

Finding ways to prevent changes anddeterioration in the sensors, which operate on
the principle of chemical reaction

Composite fiber-optical sensors (reflective type, permeation
The chemical and structural durability of thetype, etc.)
sensor and fiber materials is unknown.
Other combined- Stress: changes in the characteristics of light permeation
Reflecting knowledge of optical fiber cables,
measurements- Chemistry: light wavelengthetc.
- Sensible heat: light wavelength, changes in refractive index
Regarding Measured items & Measurement method, refer to IAEA (2001), POSIVA (2003), and SKB (2001)
Regarding Composite fiber-optical sensors, refer to Jobmann (2000)

3.3 Transmission Technologies That Use Wireless Underground Communications
In Japan, the geological disposal of high level radioactive waste entails the emplacement of thewaste at least 300 meters underground. In order to confirm that a repository, especially the vicinityof near-field at that depth is operating safely, remote monitoring would be listed as useful technique.
However the remote monitoring technique tends to decrease as the distance from where it is
implemented to the repository increases. As a possible alternative to remote monitoring, repositorybased techniques are thought to hold considerable promise in terms of measuring data directly,
especially if repository-based monitoring can be combined with wireless transmission technologies.
Therefore, it is worth exploring the possibilities of wireless transmission technology which could beapplied to the radioactive waste disposal even after repository closure.
Wireless transmission can make use of electromagnetic waves (including light) or sound waves.
From the perspective of suitability for geological disposal monitoring, the high-frequency range ofelectromagnetic waves that is normally used for communications is considered inappropriate
because of the significant degradation that occurs when the waves pass through the transmission
media of water and rock. In practice, optical communications require the use of cables, whereas
communications based on sound waves suffer fundamental problems related to signal deteriorationand limitations on how much data can be transmitted.
In contrast to these options, the use of low-frequency electromagnetic waves is considered the mostapplicable, based on actual results obtained under conditions that resemble geological disposalmonitoring, such as the transmission of measurement data on ground subsidence(Reclaimed groundsubsidence monitoring for Kansai International Airport,2000 〜 ), and applications in civilengineering. Development is therefore being pursued in this area, including efforts to reduce the sizeof transmitters and receivers (which have been quite large until now) and to reduce energy
consumption through function verification tests in actual underground environments. The prototype
units used in these tests is shown in Photo 3.1 below.
Tests were first conducted on underground wireless transmission using low-frequency
electromagnetic waves undertaken by RWMC in 2002, by the courtesy of SKB, at the Hard RockLaboratory (HRL) in Sweden, where it was confirmed experimentally that basic communication
could be achieved. Through a comparison of the results of these tests with a theoretical analysis ofelectromagnetic wave transmission, theoretical studies are being conducted on the basic
characteristics of underground communications. As shown in Figure 3.1, the communications test
results obtained at HRL are reproduced analytically, showing the receiving characteristics with theconductivity of different underground mediums tentatively set. In this way, the validity of themethodology is proved. From test results and the theoretical analysis of two-dimensionaltransmission implemented so far, it has been found that data can be transmitted approximately 100
meters in both uniform crystalline rock and salty groundwater environments.
Future studies will focus on analytical methods applied to three-dimensional structures, with the aimof applying the methods to various geological environments encountered in actual repositories.
These studies will be accompanied by validation tests conducted in different types of undergroundfacilities that have environmental features similar to those of the sites where the technology will be
actually used.
Studies are also needed to ascertain such variables as the depth of the repository (for example, up to
1,000 meters in crystalline rock and about 500 meters in sedimentary rock), the special
characteristics of the repository in question, as well as to help achieve longer communication
distances and determine the ability to withstand pressure, heat, and radiation. Other issues that must
be addressed include securing a power supply so that the equipment can function; improving
operability and maintainability while keeping in mind long-term reliability and applicability; andreducing equipment size.

- 26 -

Transmission side

Reception side

Transmitter
送信機

ReceiverTransmitter
送信機

φ296

受信機

Transmission andreception
送受信制御機
controller
486

430

Receiver
受信機
95

148

φ216

φ318

φ620

Figure 3.1 Underground Wireless Radios (Prototype Units) (Dimension: mm)

10000.0

1.E+01

4.0E+00

導電率一覧 ʼ００年３月２６日

2.2E+00
1.4E+00

1.E+001.1E+00

8.0E-01

6.3E-01

1.2E-01

1.0E-01

1000.06.7E-02

1.E-01 5.0E-02

Electric 導
conductivity
電率（Ｓ／ｍ） (S/m)

5.0E-02

5.0E-02

1.0E-02

3.3E-03

1.3E-02

5.0E-03

4.0E-03

3.3E-03

1.4E-02

1.0E-02

1.0E-022.0E-02

1.E-02100.0

5.0E-02

2.6E-02

3.3E-03

2.2E-03

1.E-03

1.4E-03

1.0E-03

6.7E-04

2.0E-04

3.3E-04

1.E-04

1.5E-04
1.0E-0410.0

2.0E-05

1.E-05

試験①−1
地表 Surface
Ground試験③−1スパイラル坑道上下間

Sea water
海水

KCLKC
0.1
mol/L
L 0.1mol/l

KCL KC0.01
mol/L
L 0.01mol/l

Tap water
水道水

Well water
井戸水

Groundwater
地下水

Hot spring water
温泉水

Distilled 蒸
water
留水

Surface water
地表水

Granite
花崗岩

Pure water
純水

Gyokaigan
凝灰岩

泥??rock
岩・頁岩

Sand stone
砂岩

Gravels
(dry)
）
砂利（乾

Groundwater
一般表層土

Groundwater
粘土

Betweentunnels

試験③−1アクセス斜坑枝坑間
坑道間

Clay and
Sand
粘土
＋砂

試験③−1平行坑道間

Boringボー
mud
water
水
リング泥

1.E-06

River
河川

1.0

4.0E-06

Groundwater
地下水

Receiving
Voltage (mV rms)
受信電圧[mVrms]

3.3E-01

0.1
1

10

100
距離[m]
Distance (m)1000

Result of communication test between
tunnels (Sweden: Äspö)Figure 3.2

Electric Conductivity
underground mediumsofvariousResults of Wireless Underground Communications and Data of Electric Conductivityof Underground Mediums- 27 -

Future Work Programs
The debate on what type of monitoring system to use for geological disposal will no doubt continue
as advances are made in the phased development of geological repositories. To facilitate to make adecision on such a debate, it is important to clearly indicate the technical feasibilities. To fulfill the
purpose, a technology menu for geological disposal monitoring is being worked and formulated.
This report has outlined the current status and purposes of geological disposal. Using this as afoundation, it will be considered to creating a technology menu that will contribute to thedevelopment of monitoring programs from the perspective of the 5W1H questions.
With regard to the applicability of technologies, surveys and research must still be conducted toclarify the technical feasibilities of elemental geological disposal monitoring technologies, including
measurement and data transmission technologies. Also, it is necessary to prepare and organize
technical information with regard to data in terms of taking advantage of and obtained in the field of
deep geological environments.
As has been pointed out, the environmental conditions that must be dealt with in geological disposalmonitoring require sensors and other technologies that can provide long-term monitoring. Since
there has been no market for such technologies until now, new development is required. Therefore,technical surveys ("seeds" surveys) must be continued in a wide range of advanced scientific andtechnical fields, such as space and ocean development. Also, verification tests on sensor andunderground transmission technologies conducted in the field at deep underground research facilities
must be continued both in Japan and other countries, with the aim of building more reliable
monitoring systems.

The promising geological disposal monitoring technology requires to be established in order totechnically develop more reliable monitoring system. Furthermore, the development of suchtechnology needs to be conducted performing test confirmation in the fields such as deep geologicallaboratories domestically and abroad.

Acknowledgements
This report is described on the latest information and knowledge concerning geological disposalmonitoring based on the research results obtained in the "Survey on Improving Monitoring Device
Technologies" implemented by RWMC entrusted by METI.
In completing this report, authors have benefited from the cooperation of members of the
Exploratory Committee for Geological Disposal Monitoring Systems chaired by Dr. S.Tanaka,
Professor of the University of Tokyo, and many other experts for their valuable advices. Dr. White,
Senior Consultant of the Galson Sciences Ltd, also gave us insightful comments, which wereincorporated in this report. We sincerely thank them for their kind assistance.

- 28 -

References

ANDRA: Loi No. 91-1381 du 30 decembre 1991 relative aux recherches sur la gestion des dechets radioactifs(1991).
DOE: 40 CFR Parts 191 and 194 Compliance Monitoring Implementation Plan. Document
DOE/WIPP-99-3119. DOE, Carlsbad Area Office, Carlsbad, New Mexico (1999).
EKRA: Disposal Concepts for Radioactive Waste: Final Report (2000).
EPA: Environmental Radiation Protection Standards for the Management and Disposal of Spent
Nuclear Fuel, High-level and Transuranic Radioactive Wastes, 40 CFR 191, Final Rule,
Federal Register 58, 66398 (December 20, 1993). U.S. Environmental Protection Agency,
Radiation Protection Division, Washington, D.C. (1993).
EPA: Criteria for Certification and Recertification of the Waste Isolation Pilot Plant’s Compliancewith 40 CFR 191 Disposal Regulations, Final Rule, 40 CFR 194, Federal Register 63, 2735327406 (February 9, 1996). U.S. Environmental Protection Agency, Radiation Protection
Division, Washington, D.C. (1996).
European Commission: Nuclear Science and Technology, Thematic Network on the Role ofMonitoring in a Phased Approach to Geological Disposal of Radioactive Waste, Contract No.
FIKW-CT-2001-20130, Final report, 2004 EUR 21025 EN (2004)
Nuclear Waste Management Organization of Japan (NUMO): Open Solicitation for Candidate Sites
for Safe Disposal of High-Level Radioactive Waste (2002)(in Japanese).
Nuclear Safety Commission (NSC): The Basic Policy for Safety Regulations for High-Level
Radioactive wastes (The First Report) (2000) (in Japanese).
IAEA: The Principles of Radioactive Waste Management, IAEA Safety Series No.111-F(1995).
IAEA: Retrievability of High Level Waste and Spent Nuclear Fuel. Proceedings of an International Seminarorganized by the Swedish National Council for Nuclear Waste in co-operation with the IAEA,
Saltsjöbaden, Sweden, 24-27 October 1999. IAEA-TECDOC-1187 (2000).
IAEA: Monitoring of Geological Repositories for High Level Radioactive Waste, IAEA-TECDOC1208 (2001).
Jobmann, M., Fischer, S., Voet, M.: New monitoring methods for operational safety requirements based onfiber optic technology, Distec'2000, International Conference on Radioactive waste disposal, Berlin,
Germany (2000).
JNC (Japan Nuclear Cycle Development Institute): Second Progress Report and Development for the
Geological Disposal of HLW in Japan (H12:Project to Establish the Scientific and TechnicalBasis for HLW Disposal in Japan), Supporting Report 3: Safety Assessment of the Geological
Disposal System,(April 2000).
NRC: One Step at a Time: The Staged Development of Geologic Repositories for High-Level Radioactive
Waste (2003).
OECD/NEA: Disposal of Radioactive Waste, An Overview of the Principles Involved (1982).

- 29 -

OECD/NEA: STAKEHOLDER CONFIDENCE AND RADIOACTIVE WASTE DISPOSAL,
Inauguration, First Workshop and Meeting of the NEA Forum on Stakeholder Confidence in the Areaof Radioactive Waste Management Paris, France 28-31 August (2000).
OECD/NEA: Reversibility and Retrievability in Geologic Disposal of Radioactive Waste- Reflection
at the International Level, OECD/NEA 3140 (2001).
Posiva: Programme of Monitoring at Olkiluoto During Construction and Operation of the ONKALO, POSIVA
2003-05 (2003).
Simmons, G.R., P. Baumgartner, G.A. Bird, C.C. Davison, L.H. Johnson and J.A. Tamm: An
approach to criteria, design limits and monitoring nuclear fuel waste disposal. Atomic Energyof Canada Limited Report, AECL-10737, COG-94-30 (1994).
SKB: RD&D-Programme 2001 Programme for research, development and demonstration of methods for the
management and disposal of nuclear waste, SKB TR-01-30 (2001).

- 30 -

Attachment A The Current State of International Discussions
Concerning Institutional Control

Institutional control7 has been a topic of discussion in various countries since the 1970s. One document thatmentions this subject, OECD/NEA (1982), recognizes the effectiveness of institutional control, but advocates
that, essentially, steps should be taken to formulate passive disposal methods that do not depend upon
institutional control. In OECD/NEA (1995a), an evaluation was conducted on the actions of careless workers,
and more active institutional control was mentioned. Furthermore, in OECD (1995b) the ethical problems
associated with the disposal of radioactive waste were discussed, including the need for fairness both between
generations and within a single generation. Additionally in OECD/NEA (2001), the issues of retrievability andreversibility were discussed, and further consideration was given to the 1995 inter-generational ethics issue cited
above, focusing on the rights of future generations to make their own decisions.
In OECD/NEA (1999), the word "confidence" was defined as follows: "To have confidence is to have reached
a positive judgment that a given set of conclusions are well-supported." On the basis of this definition, thereport stated that perfect knowledge of a system should not be a requirement when making decisions
concerning the development of disposal sites. Therefore, a crucial issue for people involved in the managementof radioactive waste is building confidence in the long-term safety of geological disposal, as well as finding
communication methods that inspire such confidence. To this end, the report underlined the importance ofdeveloping disposal sites in a phased and flexible manner. Further discussions on retrievability and ethicalaspects were carried out in workshops (IAEA, 2000) and a forum (OECD/NEA, 2000) focused on theconfidence of stakeholders. Debate from the perspective of public confidence continues to this day.
Within this context of international discussions concerning public confidence, IAEA published IAEATECDOC-1208, which summarizes the studies that have been conducted on the purposes of monitoring, theuse of information, and methodology.
Taking all of the above into consideration, outline of international trends regarding institutional control can besummarized as follows.
-

Principle: The assurance of the safety of geological disposal does not depend on institutional control,-

From the 1980s, the effectiveness of institutional control as a means of obtaining the necessary publicconfidence was clearly recognized by international institutions and-In recent years, the need for a flexible, phased approach to the development of repositories has been
debated, and institutional control has been given a greater role. Today, the use of monitoring (which is one
method of institutional control) is being considered, with a view toward encouraging social confidence andacceptance.

7

Institutional Control: Control of a waste site (for example, disposal site) by an authority or institution designed
under the laws of a country or state. This control may be active (monitoring, surveillance, remedial work) or
passive (land use control) and may be a factor in the design of a nuclear facility (for example, near-surface
disposal facility). (IAEA, 1995)

A−1

References
IAEA: The principles of Radioactive Waste Management, IAEA Safety Series No.111-F, (1995).
IAEA: Monitoring of geological repositories for high level radioactive waste, IAEA-TECDOC-1208 (2001).
IAEA: Retrievability of High Level Waste and Spent Nuclear Fuel. Proceedings of an International Seminarorganized by the Swedish National Council for Nuclear Waste in co-operation with the IAEA,
Saltsjöbaden, Sweden, 24-27 October 1999. IAEA-TECDOC-1187 (2000).
OECD/NEA: Disposal of Radioactive Waste, An Overview of the Principles Involved (1982).
OECD/NEA: Safety Assessment of Radioactive Waste Repositories; Future Human Actions at Disposal Sites.
A Report of the NEA Working Group on Assessment of Future Human Actions at Radioactive Waste
Disposal Sites, OECD/NEA, Paris, France (1995a).
OECD/NEA: The Environmental and Ethical Basis of the Geological Disposal of Long-lived Radioactive
Waste; Collective Opinion of the Radioactive Waste Management Committee, OECD/NEA, Paris,
France (1995b).
OECD/NEA: Confidence in the Long-term Safety of Deep Geological Repositories – Its Development andCommunication (1999).
OECD/NEA: STAKEHOLDER CONFIDENCE AND RADIOACTIVE WASTE DISPOSAL, Inauguration,
First Workshop and Meeting of the NEA Forum on Stakeholder Confidence in the Area of Radioactive
Waste Management, Paris, France 28-31 August (2000).
OECD/NEA: Reversibility and Retrievability in geological disposal of radioactive waste- reflection at theinternational level, oecd/nea 3140 (2001).

A−2

Attachment B Survey and Analysis of the status of Monitoring
Studies in Japan and Abroad

B-1

Status of Monitoring Studies in Various Countries

To assist monitoring studies in Japan, surveys on the status of monitoring studies on geological disposal
programs in various other countries were conducted from 2001 into 2002. The countries surveyed were:
Sweden, Finland, France, Switzerland, Belgium, Spain, the UK, Germany, the USA (YMP and WIPP) andCanada. In addition to perusing the literature and collecting information through the Internet and other means,the survey team commissioned reports on relevant topics from the institutions concerned in each country and,
when necessary, visited these institutions and conducted interviews.
The results of these surveys are summarized in Table B-1 below, which covers the following.

・ Approach to the management of geological disposal-

Basic approach-

Underground testing facilities for verification tests and other purposes-

Retrievability

・ Monitoring requirements imposed by regulatory bodies
・ Status of monitoring efforts by the implemental bodies, etc.
-

Necessary conditions

-

Plans

-

Conditions for the selection of monitored items

B-2
1)

Management of Geological Repositories
Phased implementation
The approach to geological disposal adopted in foreign countries is based on "The Principles ofRadioactive Waste Management," SS 111-F (IAEA, 1995), which states in principle that, with respect toradioactive waste management, necessary safety functions should depend on long-term, institutional
control as little as possible. Some countries have clearly defined basic disposal policies, while othercountries are still in the study phase. All of the countries that have established a basic policy have clearlycommitted themselves to phased repository development, with clearly indicated or implied
implementation of related monitoring.

2)

Underground Testing Facilities
Concerning underground testing facilities for such purposes as conducting verification tests on disposal
technologies, the following countries have either indicated or implemented the policies described.
-

Sweden: In the SKB program, 10% of the waste material will be emplaced in advance in the firstB−1phase of the project, and geological monitoring will be conducted for a prescribed period. The
knowledge gained from this process will then be evaluated and, if agreement is reached, a disposal
area will be constructed to house the remainder of the waste material package.
-

The US (WIPP): Part of the repository is being used as an underground laboratory for such tasks asmonitoring bedrock behavior and conducting retrievability verification tests.

Also, in Switzerland, the Expert Group on Disposal Concepts for Radioactive Waste (EKRA) has
developed a concept of long-term monitored geological disposal, which calls for the construction of test
facilities and pilot facilities in addition to the actual waste emplacement facility (main facility) in order tocarry out monitoring and management activities (EKRA, 2000). Recently in the US as well, a panel ofexperts affiliated with the National Academy of Sciences (NAS) has stated that the Yucca Mountainrepository program be pursued in stages and with a high degree of flexibility, and has recommended to the
Department of Energy (DOE) that a test phase should be planned in order to test at least the key conceptsof the project (National Research Council, 2003).
3)

Retrievability
Finland, France, and the US (YMP, WIPP) explicitly mention waste retrievability or reversibility (acomponent of retrievability) in their disposal plans or laws. It was also discovered that, spurred by recent
international study conditions, relevant institutions in other countries have initiated internal studies on
retrievability, as well.
The results of the above survey show that the recent international trend is toward phased implementationof repository development, and that issues such as retrievability are being studied. Even countries that havenot previously clearly indicated such a stance or considered the issue of retrievability, are now indicatingthat internal studies have begun. Meanwhile, international agencies are taking the lead in creating
documents and hosting workshops as a means of dealing with public decision-making (OECD/NEA, 1999
and 2000; IAEA, 2000; etc.). Hence, it turned out all countries now recognize the importance of theseissues. In view of this, further research and development must be pursued with a concomitant commitment
to exchange information and monitor the direction of future debate among different countries andinternational agencies.

B-3

Monitoring Purposes

In accordance with general safety requirements, repositories are in principle designed so that long-term safety
does not depend on the monitoring activities of future generations. However, various countries are studying thepossibility of implementing monitoring activities because of the conditions and requirements cited above in
relation to phased implementation and other regulatory concerns. The US and Canada have adopted regulations
that specify minimum monitoring requirements.
Table B-1 provides an overview of all studies in each country related to monitoring. Except for WIPP in theUS, which has already been in the operational phase, plans concerning monitoring are still in the study stage inall countries surveyed.
Note that the content cited below was valid at the time that the surveys for this research project were conducted,
but includes items that do not reflect the official views of the countries or institutions in question.
a) Supplementing safety assessments and promoting the verification and understanding of models or
hypotheses: Sweden, France, Switzerland, Belgium, Spain, UK, US, and Canada,b) Supplementing or verifying repository design/construction data: Switzerland, Spain, and Canada,c) Obtaining a baseline: Sweden, Spain, UK, Germany, US and Canada,

B−2d) Enhancing understanding, obtaining feedback, making repair decisions, etc. in order to: Canada,e) Providing information and promoting understanding to facilitate public decision-making:Switzerland, Spain, and Canada,f)Monitoring related to retrievability or reversibility: France and Spain,g) Building public confidence: Canada,h) Sustaining a sense of confidence among future generations: Switzerland,i)Reassuring to the public after site management has ended: UK,j)

Verifying that regulatory requirements are observed and obeyed: Switzerland, Germany, US, andCanada,k) Evaluating general environmental impact: Finland,l)Evaluating the non-radiological and radiological effects of the repository on the environment, thegeneral public, and repository workers: Sweden, Switzerland, Spain, UK, and Germany andm) Complying with requirements for security measures associated with nuclear non-proliferation:
Sweden, Switzerland, and Spain.

Items a) through j) in the above list can be further categorized as follows:-

Verifying the engineering measures and safety functions of the repository: a), b)-

Obtaining an environmental baseline: c)-Providing information for managerial decisions: d)-Social aspects: e), f), g), h), and i)-

Confirming compliance with legal and regulatory requirements: j)

References
IAEA: The principles of Radioactive Waste Management, IAEA Safety Series No.111-F, (1995).
IAEA: Retrievability of High Level Waste and Spent Nuclear Fuel. Proceedings of an International Seminarorganized by the Swedish National Council for Nuclear Waste in co-operation with the IAEA,
Saltsjöbaden, Sweden, 24-27 October 1999. IAEA-TECDOC-1187 (2000).
EKRA: Disposal Concepts for Radioactive Waste: Final Report (2000).
NRC: One Step at a Time: The Staged Development of Geologic Repositories for High-Level Radioactive
Waste (2003).

B−3

OECD/NEA: Confidence in the Long-term Safety of Deep Geological Repositories – Its Development andCommunication (1999).
OECD/NEA: STAKEHOLDER CONFIDENCE AND RADIOACTIVE WASTE DISPOSAL, Inauguration,
First Workshop and Meeting of the NEA Forum on Stakeholder Confidence in the Area of Radioactive
Waste Management, Paris, France 28-31 August (2000).

B−4Table B-1 Results of Monitoring Surveys in Foreign Countries (1 of 3)

Retrievability

B−5

Approach to managing geological disposal
Undergroundtesting facilities

Basic approach

SurveyItem

SwedenFinlandFranceSwitzerland

The basic conditions for managing repositories
in Sweden are as follows:
1. The long-term safety of the repository
should not depend on the monitoring ormaintenance activities of future
generations. However, this does notnecessarily mean that no monitoring will be
performed after waste disposal or site
closure;2. The design of the repository must not
obstruct any future decisions concerning
repository modification or waste retrieval
and
3. Knowledge concerning the waste material,
the disposal system, and the disposal sitemust be preserved in a logical and ongoingmanner.

STUK has adopted the following approach torepository management: "To ensure long-term
safety, disposal shall be undertaken in such a
way as to not require repository monitoring. In
addition, planning must accommodate thepossibility of waste canister retrieval in the eventthat technical development generates favorable
options."

Switzerland's approach to repository
management is as follows: "In Switzerland, longterm repository safety must be achievable
without dependence upon post-closure
monitoring or (institutional) control."In addition, a report issued by EKRA states thatthe goal of long-term repository management
should be "the protection of human beings andthe environment; the assurance of fairness, bothfor future generations and between generations;and to facilitate the societal decision-making
process."

SKB will dispose of waste in phases as therepository is developed. The geologicalrepository is being constructed in two phases. In
the first phase, 10% of the total waste will be
emplaced and an assessment will be conducted.
If the predicted results are obtained in the firstphase, the second phase will be initiated.
SKB studies reversibility in each phase. SKI is
now formulating regulations that include current
requirements for retrievability.

No concept of a demonstration area was foundin Finland (at least not in the publishedinformation that was surveyed for this study).

In the law regarding the management ofradioactive waste, the principle of reversibility isincorporated in the following article:"(Authorization for disposal) will be implemented
in each stage. Therefore, reversibility is anecessary condition for each stage. All built
structures, etc. must be removed when therelevant authorization period ends."
Also, a law promulgated in 1992 emphasizes theneed for retrievability by stating: "In any type of
research concerning the effects of waste
facilities, reference must be made both to site
restoration conditions and to waste retrieval
technologies that should be used in the eventthat other technologies cannot be introduced."
In France, the concept of "reversibility" isbroader than the concept of "retrievability," andincludes the discontinuation of operations.
No concept of a demonstration area was foundin France (at least not in the information that was
surveyed for this study).

As cited above, France has established laws
concerning retrievability and, to make it possible
to implement reversibility in geologicalrepositories, considers it important for ANDRA tounderstand in specific terms how the repositoryis actualized and operated at each stage, as well
as all chemical, hydraulic, and mechanicaldisposal activities. The following is also explicitly
stated: "If the concept of reversibility is includedin the design, there is nothing to prevent therepository from being completely or partially
backfilled. Therefore, at the start of the project,methods for retrieving waste containers (forexample, special handling technologies toprotect workers from waste-container
radioactivity, etc.) must be given the samepriority as the concept of disposal."Swiss policy regarding the perspective of society
and the issue of retrievability is recorded asfollows: "Measurements of any kind
implemented for the purpose of waste retrievalor repository monitoring/management shall not
be allowed to compromise the essential functionof the repository as a safety barrier."
In response to this policy, the EKRA reportstates that "societal demands continue to tend
toward the concept of retrievability. Therefore,
EKRA developed its 'Concept of Geological
Disposal with Long-Term Monitoring,' which
deals simultaneously with the two issues ofdisposal and retrievability."

Posiva has just begun to formulate plans toensure retrievability. These are expected toinclude policies (not yet officially announced)
regarding monitoring and retrievability both
before and after site closure. Until now, Posiva'sview has been that "the current disposal concept
fully satisfies requirements for retrievability."In the EKRA report titled, "Concept of Geological
Disposal with Long-Term Monitoring," it isrecommended that testing and pilot facilities bebuilt in addition to the main repository. In
response to this recommendation, Nagra plans
to conduct a study of disposal concepts.

Monitoring conditions
Plans
Conditions forselecting items

B−6

Monitoring arrangements (implemental bodies, etc.)

Regulators' monitoring
requirements

SurveyItem

SwedenSKI's basic requirements: Regarding theunderground disposal of high level radioactive
waste, the repository's long-term safety must notdepend on the monitoring and maintenanceactivities of future generations. In addition, thesafety of the repository must not be threatenedby the implementation of monitoring programs.

FinlandAccording to Finland's Atomic Energy Law, thestate has the authority to demand that measures
be taken to monitor radioactive waste andensure repository safety. General safety
requirements, however, prohibit long-term safety
from depending in any way upon repository
monitoring. Therefore, if some kind of monitoringis sought after repository closure, that monitoringcannot be for the purpose of making decisions
concerning safety or the removal of canisters.
Purposes of monitoring on SKB:
The following requirements can be found in
1. Understanding the baseline, including
Posiva's EIA report:seasonal changes, in order to determine
1.
Understanding the baseline before theand evaluate the effects of repository
repository is closed
development and operation, as well as
2.
Evaluating the repository's radiologicaleffects after closure.
effects on the environment
2. Promoting an understanding of system
3.
Evaluating general environmental effects
behavior that helps to supplement safety
4.
Complying with safeguard requirements
assessments of the repository and to verify
related to nuclear nonproliferation
models and hypotheses.
3. Evaluating the repository's non-radiologicaland radiological effects on theenvironment.
4. Confirming that, during the period of
construction and operation, nonradiological and radiological safety
requirements are met for workers.
5. Complying with safeguard requirements
related to nuclear nonproliferation.
Regulators have no specific strategy. Similarly,
A proposal for environmental follow-up
SKB has no specific plans after the site
monitoring has been prepared, which will becharacteristics have been surveyed.
implemented in two phases: one before therepository is closed, and one after. For the postclosure follow-up, Posiva proposes the following
procedures: measurement of radioactivity bothon the ground surface and in boreholes;
measurement of such aspects as groundwaterlevel, flow, and chemistry in boreholes; andmeasurement of micro-earthquakes on the
ground surface.
SKB imposes the following conditions on item
selection:
1. Can the measuring equipment becalibrated and monitored?
2. Can the predicted values be set within thescope of uncertainty?
3. Are any actions anticipated in the eventthat results fall outside the predictedscope?

FranceSwitzerland

No requirements on monitoring were found to be Swiss policy concerning monitoring further
imposed by regulators in France (at least not in states that "no measurement activity of any kind
the information surveyed for this study).
should be applied for the purpose ofguaranteeing safety. Repositories must be
designed so that they can be sealed withinseveral years." This statement is also included in
the EKRA report.

ANDRA sets the following monitoring
requirements: "Monitoring of the undergroundenvironment must be specified in accordancewith all periods of reversibility and all phases of
implementation. In particular, it is necessary todevelop instruments to monitor changes in theunderground environment, the facilities, and thewaste containers." To this can be added the"monitoring for reversibility" cited above.

Nagra defines the monitoring purposes in eachphase as follows:
1. Supplementing the repository's design,
construction, and safety assessment data
2. Collecting data to verify compliance withregulatory requirements and to understandthe radiological and non-radiological effectsof the repository on workers, the generalpublic, and the natural environment
3. Providing information to facilitate the publicdecision-making process regarding therepository's phased developmental process
4. Verifying compliance with security
requirements
5. Sustaining the confidence of future
generations

To achieve the monitoring purposes related toreversibility, ANDRA assumes the following
measurements:
1. Observations and measurements ofchanges in the constituents of thedeposition hole and tunnel
2. Measurements of the environment
surrounding the deposited waste
containers
3. Measurements of the repository
environment to verify conformity withpredicted repository performance
ANDRA has adopted the following policy:"Monitoring of the underground environment
must be specified in accordance with all periodsof reversibility and all phases of implementation.
In particular, it is necessary to develop
instruments to monitor changes in theunderground environment, the facilities, and thewaste containers."

Nagra has set monitoring purposes forrepositories, but because regulators do not
require long-term monitoring, it could be foundno official positions based on a discussion ofdetails such as: what parameters should bemonitored during each phase of repository
development; what measuring technologies
should be used; what performance standards
and acceptance criteria should be used; andhow monitoring results should be used indecision-making with regard to final closure,intervention, and retrieval.

Table B-1 Results of Monitoring Surveys in Foreign Countries (2 of 3)

Basic approach
Undergroundtesting facilities
Retrievability

Regulators'
monitoring
requirements

B−7

Approach to managing geological disposal

SurveyItem

Belgium

Spain

NIRAS/ONDRAF is developing their geological disposal concept
as follows: "In principle, a system that does not require or depend
upon monitoring."
However, even if it is judged that retrievability is necessary, thecurrent disposal concept poses no technical problems. In such acase, however, repository monitoring will become an indispensable
element.

Currently, Spain's concept of deep geological disposal is basedon the idea of the final disposal of radioactive waste, without
considering retrieval. Regulators were found to have no official
stance concerning retrievability.

U.K.

The guidelines formulated by the UK's Environment Agency(1997) establish the following four principles as conditions thatmust be fulfilled before approval can be given for the disposal ofradioactive waste:
Principle 1: Safety that does not depend on management
Principle 2: Future impact
Principle 3: Optimization
Principle 4: Radiation protection standards
The administrative interpretation of Principle 1 dictates that theclosure provided by the disposal system after the repository is
closed, and the continuous safety of future generations inparticular, must not depend upon such activities as monitoring,overseeing, preventive action, or restorative action. If thisrequirement is not met, the regulators shall not authorize
disposal.
No concept of a demonstration area was found in Belgium (at least No concept of a demonstration area was found in Spain (at least The UK has not established whether or not a demonstration
not in the information that was surveyed for this study.)
not in the information that was surveyed for this study.)
area is required, nor has it defined which phases of repository
development would be affected.

Currently, Belgium has no laws/regulations or authorization
requirements concerning the retrieval of HLW or spent fuel. A
Cabinet order has been officially issued regarding LLW, however,and it is possible that the same conditions will be applied to thedisposal of HLW or spent fuel in the future. NIRAS/ONDRAF
defines the purposes of retrievability as follows.
1. To protect the rights of future generations with regard toenvironmental protection, including the wish to intervene
concerning the level of contamination sources and theeruption of unexpected civil unrest.
2. To ensure an access method in case the decision is made touse spent fuel as a resource.

Although regulators are not considering retrievability as statedabove, regulatory conditions for retrievability have been
established for ENRESA's ILW/LLW disposal sites, and it ispossible that retrievability will become required for HLW deep
geological disposal, as well. ENRESA has decided to conduct
research on the significance of retrievability vis-à-vis repository
design and safety, with a view to encouraging public acceptanceof the phased development of deep geological repositories.
ENRESA also gives the following three reasons for retrieval:
1. The development of new technologies such as partitioning
and transmutation (PT)
2. Reuse of energy sources (U, Pu)
3. In cases where it is clear that repository safety conditions
are not adequate
Because Belgium has no laws or ordinances concerning long-term (At least not in the information surveyed for this study)
monitoring, no decisions have been made (at least in theinformation surveyed for this study) concerning how monitoring
results are to be reflected in areas such as: monitored items ineach phase of repository development; measuring technologies;
performance standards and acceptance criteria; and decisionmaking concerning final closure, intervention, and retrieval.

Nirex believes that it may become necessary to remove backfill
and reach the containers after the arch-shaped underground
vault has been backfilled to seal the repository. To demonstratethat such a retrieval operation is possible, it conducted an actual
validation test, in which life-size waste containers were removed
from a backfilled repository through the use of water jets androbotic arms.

In addition to the basic principles, the guidelines include 11
supplemental requirements, one of which concerns monitoring.
It states: "To maintain safe conditions, the developer must
implement a program to monitor any changes that are caused
by facility construction and waste emplacement."

Monitoring conditions
Plans
Conditions forselecting items

B−8

Monitoring arrangements (implemental bodies, etc.)

SurveyItem

Belgium

Spain

NIRAS/ONDRAF is developing their geological disposal concept
Monitoring is thought to be needed in Spain for the following
as follows: "In principle, a system that does not require or depend reasons:upon monitoring." However, if disposal is developed with the idea
1. Providing knowledge (including a baseline) for use inthat retrievability is necessary in order to gain public acceptance,
repository design and construction and in the assessment
long-term monitoring becomes an objective. In such a case,of repository long-term safetymeasurement would be carried out with the following goals in
2. Providing knowledge for evaluating the impact on workers,mind:
the public, and the environment
1. Confirming model data by comparing measured values with
3. Safeguard requirements for nuclear non-proliferation
predicted values
4. Providing data on retrievability and verifying that the
2. If a good match is found between measured and predicted
system is performing as expected, thereby supporting thevalues, using those results to build confidence in performance
public decision-making processassessments

The monitoring posited by NIRAS/ONDRAF is as follows:
1. Near-field monitoring during the operational period or before
closure of the transport galleries
2. Far-field monitoring after the repository is closed
Because Belgium has no laws or ordinances concerning long-termmonitoring, no decisions have been made (at least in theinformation surveyed for this study) concerning monitored items
and measuring technologies.

No specific studies concerning monitoring are being carried out
at present. However, the formulation of a future monitoring
strategy is a main component of the iterative process that iscurrently underway in Spain, and it is expected that monitoring
will be implemented when the deep geological disposal ofradioactive waste is carried out.

U.K.
The guidelines formulated by the UK's Environment Agency(1997) include the following policies concerning monitoring:
1. To maintain safe conditions, changes caused by theemplacement of waste and the construction of facilities
must be monitored.
2. Rational methods and implementation plans must be
established for monitoring the site and facilities. Monitoringprocedures must not compromise the facility's long-term
safety.
3. To obtain a baseline, monitoring must be initiated in thesurvey and pre-construction phases. It is also necessary tomeasure geological, physical and chemical parameters
regarding behavioral changes and safety issues arisingfrom construction and waste emplacement.
4. Radiological monitoring must be implemented, radiation
limits must be observed, and public proof of radiologicalprotection assurance must be shown.
5. On the basis of Principle 1, the guarantee of facility safety
after management has ended must not depend on
monitoring or supervision. Monitoring is to be implemented
primarily for the sake of reassuring the public.
The UK currently has no plans concerning monitoring.

Table B-1 Results of Monitoring Surveys in Foreign Countries (3 of 3)

Underground testing
facilities
Retrievability

Regulators'
monitoring
requirements

B−9Approach to managing geological disposal

Basic approach

SurveyItem

Germany

U.S.A.（YMP）

U.S.A.（WIPP）

CanadaDBE's approach to monitoring is based on the
IAEA principle that the safety of geologicaldisposal must not depend on monitoring. The
German government has not designatedspecific monitoring items, but does demandcompliance with regulations. With regard tomonitoring, therefore, DBE indicates conformity
with regulations, and interprets this as one
method of receiving authorization. Afterauthorization is received, DBE also indicatesthat the status of the repository conforms topredictions, and uses monitoring as a way ofenhancing confidence in system safety.

YMP authorizes and operates disposal on thebasis of calculated overall system performance
results that predict the long-term behavior of therepository during and after the regulatory period.
To provide data for performance assessment, it
implements performance confirmation programsin every operational phase. Also, in accordancewith the Nuclear Waste Policy Act and otherlaws, retrievability must be sustained for 50
years from the time that operations are initiated.
In 2003, the board of the National Academy of
Sciences recommended to DOE that therepository program should be pursued in ahighly flexible, phased approach.
No clear concept of a demonstration area wasfound in the USA (YMP) (at least not in theinformation that was surveyed for this study).
However, performance confirmation programs
are planned for all phases of YMP, including
repository site selection, approval, construction,
operation, and monitoring, and validation
concerning disposal will be implemented inside
the facility.

DOE (the WIPP operator) is required to submit
to the EPA (the regulator) a compliancerecertification application every five years. This
procedure is intended to verify that disposal isbeing appropriately implemented and that thedisposal system is safe. Also, 40CFR Part 191
establishes that the disposal system must notlimit the possibility of retrieval.

In Canada, general participation and monitoringare implemented continuously throughout theoperational period, and public consensus
obtained through this process forms the basis
for progress through each developmental
phase. An extended monitoring period aroundthe time that the site is closed is believed tomake a particularly important contribution to
public agreement concerning final site closure.

Part of the WIPP repository is used as anunderground laboratory. This part serves as ademonstration area in that it was used to
conduct geological surveys during the site
selection phase, and is now being used formonitoring bedrock behavior and verifying
retrievability.

No information concerning proof of retrievability
was found in the public information that was
surveyed for this study. However, among theplanned performance confirmation programs,
there is one that calls for the verification ofmaterial depletion of the waste emplaced in thetunnel, and it is conjectured that this program
would serve as a means of proving waste
retrievability.

In 1992, retrieval was verified at WIPP. All
retrieval operations were performed using
remote-controlled equipment.

Canada has not publicly announced any
concept concerning an official demonstration
area. However, AECL is considering placing
one or more waste containers for validation use
in a demonstration area and installing mediationmaterial (to act as a surrounding barrier), backfill
material, and an appropriate monitoring systemin the bedrock for continuous monitoring until
the closure phase. It is also considering
retrieving the waste containers.
No studies have been conducted on specificmethods of demonstrating retrievability. In
theory, however, AECL has indicated that
retrieval is achievable using current
technologies.

The minimum number of monitoring items froma regulatory perspective is presented in 10CFRPart 60 (code of federal regulations concerning
repositories for high-level radioactive waste)
and 10CFR Part 63 (code of federal regulations
regarding the Yucca Mountain site).

The minimum number of monitoring items froma regulatory perspective is presented in 40CFRPart 191 (code of federal regulations concerning
high-level TRU) and 40CFR Part 194 (code offederal regulations regarding WIPP).

No concept of a demonstration area was foundin Germany (at least not in the information thatwas surveyed for this study).

Until now, Germany has defined the final
disposal of radioactive waste as themaintenance-free, safe, and final removal ofwaste. Therefore, there were absolutely no
retrieval plans. In accordance with this definitionof radioactive waste disposal, Germany has nostandards regarding the retrievability ofradioactive waste from repositories. However, inlight of the status of new international studies,
the German Federal Government is currently
conducting a review regarding the retrievabilityof radioactive waste that has been disposed ofdeep underground.
There are no laws that specify monitoring items.

Regulatory requirements are indicated throughR-104 (including purposes, required items, andpolicies regarding the disposal of radioactive
waste).

Monitoring conditions

Germany

U.S.A.（YMP）

U.S.A.（WIPP）

According to DBE, monitoring consists, on the
one hand, of the recording of states of affairs
and, on the other hand of the comparison of therecorded results with assessment standards.
The recording is carried out mainly by different
types of measurement and graphical surveys.
The assessment standards are defined as limits
or operational conditions, or derived from
representative model calculations. The objectiveof monitoring procedures is the compliance withthe assessment standards. This is closely
related to safety analysis and so largely
depends on the final repository situation.

Monitoring at YMP will be implemented (as ofFebruary 2001) as part of 24 performance
confirmation programs, for the purposes ofvalidating and verifying engineering
technologies associated with the performance,
construction, and operation of the repository.

The objectives of monitoring at WIPP are as
follows:
1) Verifying conformity with all state
regulations, official ordinances, federal
regulations, and health and safety
requirements
2) Providing characteristic values used in site
selection
3) Providing data that indicates a baseline
4) Providing data that verifies performanceassessments (PA) and predictions, andminimizes uncertainty

Plans

DBE is giving consideration to monitoring items
that would satisfy the requirements set forth byGermany's mining laws and by safety
regulations formulated by relevant regulatory
bodies.

Conditions for selecting
items

B−10

Monitoring arrangements (implemental bodies, etc.)

SurveyItem

CanadaCanada indicates the following purposes ofmonitoring:
Understanding the baseline•
Determining conformity with legal and•regulatory requirements
Checking the performance of the disposal•
system and its elements
Verifying functional assessment and•design assumptions
Enhancing understanding of and•confidence in elements (natural barriers,
engineered barriers, facilities, waste, etc.)
and processes (construction andoperation methods, etc.)
Verifying predictions of performance•assessment models
Providing understanding and feedback for•
improved operations
Deciding on the need for repairs and•predicting repair results
Providing information and understanding•for decision-making
Building public confidence•
Twenty-four performance confirmation
Monitoring is implemented according to the
The following are considered monitoring
programs are planned for the YMP repository.
compliance application, which establishes 10
programs that should be implemented in the
In the current site selection phase, two or three monitoring parameters that apply before
future:programs have been initiated. Future programs repository closure and five items after closure.
1. Baseline monitoring: measuring thewill be initiated after detailed studies have beenbaseline conditions of a designated site
completed.
before disruptions are caused by project
activity
2. Conformity monitoring: verifying that
disposal project operations satisfy
regulatory requirements and performance
criteria
3. Performance confirmation monitoring:approving design assumptions, promoting
understanding of the disposal process,and verifying performance assessment
models
DOE is currently working on a detailed study
At WIPP, monitoring items were selected for the The method for selecting specific monitoring
called the "Assessment Plan for Testing andcompliance application. The items wereitems has not been studied.
Analysis," which concerns material testing andselected on the basis of FEP andmonitoring. According to a preliminary draft oflegal/regulatory requirements, withthe plan, consideration is being given to
consideration given to such aspects as
selecting monitoring items on the basis of legal sensitivity analysis, fluctuations over time,and regulatory requirements as well as the need uncertainty, and measurability.
to verify repository performance, while taking
into account such elements as measurability
and uncertainty.

Attachment C Record of Workshop on Monitoring

This attachment summarizes the main points covered at the "Workshop on Monitoring of Geological
Repositories for HLW (The Present Status, Framework and Issues of Monitoring Projects”), which wassponsored by Radioactive Waste Management Funding and Research Center (RWMC) on February 18, 2002.

C-1

Workshop Overview

Date:
Place:
Purpose:Participants:

February 18, 2002
Toranomon Pastoral (4-1-1 Toranomon, Minato-ku, Tokyo)
Review of and information exchange on monitoring-related research conducted by the RWMC

Satoru Tanaka, Prof. (Chairman)

University of Tokyo

Ferruccio Gera
Daniel B. Bullen
Michael J. Apted
Richard L. Beauheim
Eric Webb
Cecelia Williams

Member to drafting and review of IAEA-TECDOC-1208
Iowa State University, Member of NWTRBMonitor Scientific LLC
Sandia National Laboratories (SNL)
Sandia National Laboratories (SNL)
Sandia National Laboratories (SNL)

Tomoki Sibutani
Hiroo Numata
Kazuhiko Tamate
Hidenari Akasaka
Mitsuo Takeuchi
Katsuhiko Ishiguro
Kaname Miyahara
Tai Sasaki
Susumu Takada
Yasuhiro Mitani
Takao Tsuboya
Jin Ohuchi
Ai Fujiwara
Hajime Takao
Kazunori Sugiyama
Osamu Kato

Ministry of Economy, Trade and Industry (METI)
Ministry of Economy, Trade and Industry (METI)
Ministry of Economy, Trade and Industry (METI)
Nuclear Waste Management Organization of Japan (NUMO)
Nuclear Waste Management Organization of Japan (NUMO)
Japan Nuclear Cycle Development Institute (JNC)
Japan Nuclear Cycle Development Institute (JNC)
Japan Nuclear Fuel Limited (JNFL)
Central Research Institute of Electric Power Industry (CRIEPI)
Kyushu University
Radioactive Waste Management Funding and Research Center (RWMC)
Radioactive Waste Management Funding and Research Center (RWMC)
Radioactive Waste Management Funding and Research Center (RWMC)
Radioactive Waste Management Funding and Research Center (RWMC)
Radioactive Waste Management Funding and Research Center (RWMC)
Radioactive Waste Management Funding and Research Center (RWMC)

Takao Ikeda; Atsushi Mukunoki; Junichi Ishiguro; Takeshi Sugiyama (JGC Corporation)
Shigeyuki Saito; Ryoichi Sasaki; Kouhei Yamaguchi (Mitsubishi Materials Corporation)
Mitsuaki Furuichi; Kazuo Okutsu; Kazuhiko Masumoto; Hisashi Takamura (Kajima Corporation)
Kiyoshi Amemiya (Hazama Corporation)
Takamichi Kito; Yoshihiko Takubo (Mitsubishi Research Institute, INC.)
Norio Nakayama (National Institute of Advanced Industrial Science and Technology)
Shigenobu Hirusawa; Masahide Nakamura (The Institute of Applied Energy)
Makoto Yoshizoe; Kenichiro Sugita (Mitsubishi Corporation)

C−1

The following presentations and discussions regarding the monitoring of geological disposal were conducted at
this workshop:
1) Explanation of research conducted by the RWMC
2) The status given to monitoring in the IAEA technical document, IAEA-TECDOC-1208
3) Monitoring at the Yucca Mountain Project (YMP)
4) Monitoring at the Waste Isolation Pilot Plant (WIPP)
5) Discussion and conclusion
The main points concerning 2) and 5) above are summarized below.

C-2

The Status Given to Monitoring in IAEA-TECDOC-1208

The main points covered by the editor of IAEA-TECDOC-1208, Mr. Ferruccio Gera, in his presentation andquestion-and-answer session are summarized below.
First, Mr. Gera explained that IAEA technical documents are premised on a phased approach to geologicalrepository development. According to that premise, decisions must be made before a project can move fromone phase to the next, at which time it is essential to rationally understand the issues involved. If decisions are
made by a regulatory authority, that authority must verify safety, and the safety case that is made must be basedon a database. Monitoring has many purposes, but one of the most important long-term purposes is to advocate
a safety case. For that, Mr. Gera explained, a robust debate is needed so that safety advocacy that overcomes
uncertainty can be made to enable safety advocacy that overcomes uncertainty.
The IAEA technical document cites the following five purposes of monitoring.
Purposes of Monitoring (IAEA-TECDOC-1208):(1) To provide information for making management decisions in a stepwise program of repository
construction, operation and closure,(2) To strengthen understanding of some aspects of system behavior used in developing the safety casefor the repository and to allow further testing of models predicting those aspects,(3) To provide information to give the public the confidence to take decisions on the major stages of therepository development program and to maintain confidence, for as long as society requires, that therepository site is having no undesirable impacts on human health and the environment,(4) To accumulate an environmental database on the repository site and its surroundings to assist future
decision makers and(5) To address the requirement to maintain nuclear safeguards, should the repository contain fissile
material such as spent fuel or plutonium-rich waste

C−2Based on the results of detailed studies of the above purposes and related phenomena, potential monitoring
parameters were divided broadly into the following six categories:♦

Degradation of repository structures,♦

Behavior of the waste package and its associated buffer material,♦

Near-field chemical interactions between introduced materials, groundwater and host rock,♦Chemical and physical changes to the surrounding geosphere,♦

Provision of an environmental database and♦Nuclear safeguards(IAEA-TECDOC-1208)

Also, concerning monitoring in general, the following considerations were emphasized:-

To make rational decisions, cost effectiveness must be analyzed. In other words, it is necessary tounderstand the advantages and disadvantages of implementing a monitoring program. In particular, thedisadvantages of inserting measuring devices must be fully understood, including their impact on longterm safety.

-

Some people believe that once a safety case has been accepted, no additional monitoring is needed.

-

Near-field monitoring threatens degrading repository performance. One solution can be come up withusing a test facility. is to use a test facility. In such a scenario, three levels of measurement might be
implemented: sufficient actual measurements to instill onsite confidence; sufficient measurements toenable the parties concerned to make decisions with confidence; and sufficient measurements to clarify
the behavior under typical repository conditions.

Finally, Mr. Gera brought up the following subjects concerning the ethical aspects of monitoring.
-Some make the argument that, if the burden of monitoring is to be placed on future generations, thenefforts should be made to properly prepare the resources that future generations will need to performthe monitoring. Thought must therefore be given to developing a mechanism that will ensure this,-However, it is impossible at present to predict what decisions will be made by future generations.
Therefore, we have only an uncertain basis for thinking about the mechanism mentioned above,-

This matter must be discussed at the international level, but ultimately decisions will probably be madeat the national level. It is important for all concerned parties to participate, and for progress to be madewith the understanding that this is a "learning process " and-It is also necessary to recognize that, even if certain decisions are made today, they might not be applied
without modification by future generations.

Mr. Gera also prepared written responses to questions about the IAEA technical document in advance of theworkshop. They include the following content concerning post-closure monitoring, which is a topic that was notadequately explained on the day of the workshop.

C−3

Concerning retrievability: Content on retrievability can be broadly divided into two options. One involves
delaying the placement of the Engineered Barriers (EB) to enable the waste material to be accessed easily overan extended period of time. The other is to place the barriers in such a way that they can be returned to their
original positions as needed.
Concerning post-closure monitoring: There is widespread agreement that, in view of the continuous, longterm danger posed by most radioactive waste that is disposed of in geological repositories, there must be rational
guarantees that the disposal system will passively realize the required safety level. This means that, once therepository is closed, its safety should not depend upon any kind of institutional control, including monitoring.
Knowledge acquired regarding this point indicates that adequate safety can be achieved by doing two things: 1)
selecting a site and host rock with appropriate characteristics; and 2) ensuring that the multi-barrier system used
is solid and reliable enough to ensure waste isolation at the required level. Despite this, waste management
programs in many countries are having difficulty obtaining the authorization necessary to construct geologicalrepositories for long-lived radioactive waste. This difficulty can be traced to some public doubt regarding thesoundness of the proposed disposal method (that is, abandoning the repository once it has been closed andrelying solely on the effectiveness of its multi-barrier isolation system). In addition, there is a specific reason
continued management and monitoring of the repositories which store substances that cannot be placed outsideof the safeguard system may be justifiable. These considerations gave rise to proposals for a more flexible
approach, which can be summarized as follows.
- The long-term safety of geological repositories that store long-lived radioactive waste must be
assured with safety cases that do not depend (either scientifically or technically) on institutional
control (including monitoring) after repository closure. However, if continued monitoring after
repository closure would make decision-making easier and help to alleviate public fears, there is no
reason to disallow certain designated countries from continuing post-closure monitoring.
-

Because post-closure monitoring activities are not carried out for the sake of safety requirements, it is
impossible to establish a priori during a set period for these activities. It is therefore important toindicate that this point depends upon the reevaluation and decision-making carried out by future
generations.

-However, it is essential that any and all activities carried out after closure be planned and executedwithout compromising the safety of the geological disposal system.

C−4

C-3

Discussion and Wrap-Up

Discussions were pursued at the initiative of Dr. Michael J. Apted. The main discussion points are summarized
below.
First, opinions were exchanged concerning the definition of "monitoring." Monitoring is defined in IAEATECDOC-1208 as follows: "Continuous or periodic observations and measurements of engineering,
environmental or radiological parameters, to help evaluate the behavior of components of the repository system,or the impacts of the repository and its operation on the environment." In response to this definition, Dr.
Beauheim mentioned that the definition should also include the monitoring of human activity.
Next, it was proposed that the following distinctions be made between the two following pairs of terms, which
are easily confused: "variability/uncertainty," and "reversibility/retrievability."
Variability: Natural variation or properties and conditions of a repository system (a property of the system).
For example, it refers to baseline behavior such as the year change of an underground water level, a long-term
tectonic movement.
Uncertainty: Limitations in our knowledge or ability to measure properties of repository systems. There aredifferent kinds of uncertainty, including measurement uncertainty, conceptual model uncertainty, and scenario
uncertainty.
Reversibility: An approach in which each step of repository implementation is fully reversible, including
retrieval of waste during closure.
Retrievability: A sub-set of reversibility in which waste can be retrieved to the surface (up until the time ofpermanent closure).
Dr. Apted said that, historically, the concept of retrievability was introduced in the US in the late 1970s.
Recently, the concept of reversibility has been discussed in an effort to grasp a broader meaning. Concerning
this, Mr. Gera introduced the following information about historical developments at IAEA. Reversibility was
originally proposed by the French delegation and was adopted as a general term after discussion, as most people
believed that there were serious problems associated with seeking retrievability, which meant leaving therepository open by not backfilling it. Reversibility was proposed as a possible solution, at which point theSwedish delegation stated that, if the waste packages were robust
enough to remain sound for thousands of years after backfilling,
the disposal concept of reversibility
Site
could still be adequately addressed by pursuing the original
Monitoring
Characterization
repository plans.
Next, in discussions concerning monitoring, Dr. Apted presented
Figure C-1, which clarifies the relationships between relevantterms, and provided the following explanation. Figure C-1
tabulates some of the activities at Yucca Mountain, with reference
to "performance confirmation." Performance confirmationencompasses the major issue of monitoring, as well as sitecharacterization, laboratory testing, the need to conduct actual
onsite studies (such as measuring bedrock pressure), andequipment testing and retrieval technologies. Figure C-1 showssome of these activities. In this way, performance confirmation
involves collecting information beyond these boundaries. In
addition, performance confirmation takes on uniquecharacteristics depending on the specific site, the concept and thehost rock. In any case, quality assurance applies to all parts. For
example, the entire program must be written down so that

C−5

Performance
Confirmation

Laboratory
Testing

Equipment
Testing

Quality Assurance（Everywhere）

FigureC-1

Relationships of terms and“Monitoring”

decision content can be tracked.

Dr. Apted compiled the comments received from workshop participants and used them as discussion points forcontinued explanation. First, why should monitoring be done? This question needs a specific answer.
Monitoring might reflect many different kinds of objectives. It might be used to implement changes over theservice life of the repository. More generally, it might be used to provide back-up for decisions made in a phased
process. In the case of the US, monitoring is a regulatory requirement. Planners at Yucca Mountain must present
evaluative conditions not only to regulators but also to a public, independent peer review group showing that
their activities are safe. In addition, monitoring is necessary to guarantee safety to the public and to gain public
acceptance. Other objectives for monitoring, though not directly relevant here, include ensuring worker safety
and performing proper environmental stewardship. What should be monitored? It must of course be measurable
parameters. When should monitoring be implemented? A baseline should be initiated at an early stage in theprocess. How good should the monitoring be? This question relates to such issues as determining what trigger
level indicates that conditions are not normal; what values will trigger action; and what actions will be taken if
predictions and measured values do not match. How will monitoring be implemented? A system is needed thatcan withstand a harsh environment over a long period of time. Dr. Apted said that strategies that have been
adopted in the aerospace field might prove useful.
Dr. Apted presented a table showing how different monitoring purposes come into play in different phases ofgeological disposal operations, and continued discussions (Table C-2).

C−6

Table C-2 Disposal Stage and Monitoring Objective
Monitoring objective
Decision support

SitingApplies

Operations
Applies

ClosureApplies

Confirm site

Applies（Baseline）

Applies（Large volume）

Applies（Long-term）

Post-closure
No apply(After the closure procedure has
been approved , no monitoring
or institutional control isneeded.)No apply?

Confirm engineered barriers

No apply

Applies（Long-term）

No apply?

Safeguard

No apply

Applies（WP−WP）（WP−Host rock）
Applies

Applies

Applies（Remote surveillance）

C−7

Public acceptance

Regulator/tech peer review

Optimization

Applies
Applies
Applies
Applies(Are the local residents of the (Can local residents withdraw if (Can monitoring be used to (Maintaining long-term surface
candidate--site safe even after they find the site or concept confirm the appropriateness of monitoring measures for as longsite characterization has been unsatisfactory?)thepremisedconditions as society deems themregarding safety and the model desirable: Stewardship)
approved?)
used?)
Applies
Applies
Applies
No apply（scenarios, robustness）?
Applies（Site characterization）

Applies（Repository design）（Engineered barrier design）

No apply

No apply

The following opinions were exchanged among participants during the discussion:
-

-

-

-

-

-

While it is important to maintain flexibility, in the US example such a policy also has disadvantages.
There are limits to pursuing confidence only through safety and performance assessments, and it may
be worth using natural analogues and monitoring to raise confidence and reduce uncertainty.
Concerning confidence, attention should be directed to the monitoring objective second up from thebottom of the table: namely, having reviews performed not only by regulators but also by a technicalpeer group. The peer group is likely to ask some very tough questions, and monitoring would prove
useful in such a case.
Perhaps a distinction should be made between monitoring carried out before approval applicationand that carried out after operations have begun. In the pre-approval period, monitoring can provide
extensive information useful for such tasks as gathering information, understanding the baseline,
understanding the system, and building a safety case. After operations have begun, the main focus is
on maintaining a relationship of trust with the general public, which depends on how muchinformation can be made public. Even if that information differs from predictions, the question is how
it can be publicly released. Another related issue is determining how to deal with information that has
been collected.
In verifying an engineered barrier system, monitoring has the advantage of helping us to understandprocesses that cannot be detected in the laboratory, such as the interaction between waste packages
and the bedrock. Long-term monitoring also has the advantage of increasing our understanding ofbaseline behavior.
Monitoring is effective in promoting public acceptance. Explanations can be given concerning thetypes of monitoring being implemented, such as impact on drinking water, local safety, or postclosure management. Monitoring allows operators to answer people's questions.
Monitoring provides a technical basis for providing information when studying such scenarios as
earthquakes, changes in sea level, or changes in climate.
Monitoring can also be considered to have the added value of contributing to the optimization of thedisposal system, low-cost design, and modifications in disposal methods.
There are limits to the reliability of monitoring results. If measured values are obtained that do notmatch predicted values, and it is also known that this result does not have a major impact on thesafety case, that particular item can be designated as a supplemental measurement. When specificmeasurement items are selected, their validity and basis must be designated.
The relationship between measured values and the interpretive tools used for understanding this data
must not be forgotten.
The system has a service life, which defines the monitoring period. However, it is impossible to say atpresent how long the system will continue to function.
When repository closure has been approved, there is no need from the scientific perspective tocontinue institutional control and monitoring. However, there is a social demand for continuation.
Also, there are requirements for safeguard security measures.

After the above discussion, Dr. Apted wrapped up the workshop with comments about the social and technicalaspects of monitoring, including some suggestions pertaining to research conducted at the Radioactive Waste
Management Funding and Research Center (RWMC).
Social Aspects
At candidate sites, it is important to talk to the general public about monitoring as a means of ensuring safety
now and for future generations, especially children and grandchildren. Also, focus groups are an effective wayof finding out what ordinary people are worried about, what motivates them, and what can be done to instill
confidence in them. In order to learn from past examples of these kinds of social aspects, RWMC is conducting
surveys in various foreign countries.
Technical Aspects

C−8Planning and policy-making related to monitoring will probably depend on the repository concept (site, design).
For example, the following items will have an effect: type of host rock; design of engineered barriers; important
processes related to safety; and site-specific elements (whether or not an active fault is present, relationship withthe ocean, etc.).
Also, as many of the participants stated, it is important to have a baseline. By measuring a baseline, it becomes
possible to: confirm that the selected site is appropriate; understand disturbances caused by undergrounddevelopment; compare the values predicted by the model with actual measured values; and confirm the degreeof impact on surroundings. Also, although it was not particularly discussed at the workshop, the fact that Japanis seismically very active would suggest that monitoring is indispensable from the perspective of geologicalengineering. Because temperature gradient problems, which will cause deformation of rock, are generated by
the existence of high-radiation, high-temperature locations, consideration must be given to what exactly ismonitored. In this respect, conditions in Japan can be considered more difficult than those encountered at WIPP.
In addition, for the monitoring, there is an important link between modeling of performance assessment andrelated research. The following issues must be considered: What parameters fail to match performanceassessment predictions? What is the degree of discrepancy, and do changes occur over time? What parameters
are important for the purpose of securing safety? And, can a realistic model be developed for system
optimization?
Participants had the following question concerning the last item of the above explanation: Does the link
between performance assessment and monitoring have significance within overall performance assessments? In
response, Dr. Bullen provided the following explanation based on his experience at Yucca Mountain. Because
initial surveys did not provide an adequate understanding of site characteristics, it was impossible to design
appropriate waste packages, and this had an impact on cost evaluations. This was a lesson learned in the US, but
if it is possible to understand the site by linking monitoring with performance assessment, it is important toincorporate that concept into the design immediately. This will enable a realistic response to conduct costestimates.

C−9

Attachment D The Status of Safety Cases and AssociatedMonitoring

The concept of "safety cases" has been discussed in recent years, especially with regard to the safety of highlevel radioactive waste disposal. A safety case is a larger framework designed to increase the understanding of
non-specialists (including policymakers) and the general public regarding difficult disposal technologies that are
not easily accommodated by previous safety assessment frameworks. To that end, a safety case is intended toconvey a sense of safety and secure confidence (for example, "Confidence in the Long-term Safety of Deep
Geological Repositories–Its Development and Communication–" (OECD/NEA 1999)). In Japan, this issue has
also begun to be discussed (for example, in "Waste Disposal Reference No. 6-3" (Sixth meeting, February 6,2002) (Special Advisory Board on High-level Radioactive Waste Disposal Safety of the Nuclear Safety
Commission of Japan)). Discussion concerning the status of monitoring within the safety case frameworkprovides an important basis for various other discussions on monitoring. The definition of "safety case" and therole of monitoring within it are discussed below.

D-1

Definition of "Safety Case"Three examples of definition and content of “safety case” are as follows:(1) Dr. Michael Apted presented this definition of "safety case" at a monitoring workshop sponsored by
RWMC on February 18, 2002.
Safety Case: The set of arguments and different lines of reasoning (e.g., natural analogues) that indicate
the safety of a repository system is adequate to meet safety standards and is reasonably assured.
(2) Quoted content and original expressions used in "Waste Disposal Reference No. 6-3" (Sixth meeting,February 6, 2002) published by the Special Advisory Board on High-level Radioactive Waste Disposal
Safety of the Nuclear Safety Commission of Japan"Within the context of developing and communicating confidence in the long-term safety of geologicaldisposal, a Safety Case is a collection of arguments at a given stage of repository development, in supportof the long-term safety of the repository. A Safety Case comprises the findings of a safety assessment and astatement of confidence in these findings. It should acknowledge the existence of any unresolved issues andprovide guidance for work to resolve these issues in future development stages."
Waste Disposal Reference No. 6-3 also cites the following as examples of safety assessment approaches
used in "multiple lines of reasoning" (OECD/NEA, 1999):-

Demonstrating safety through a simple and direct approach
Applying various evaluation methods
Natural analogues
Paleohydrogeology
Decisions by specialists
International consensus(3) Content on what a safety case should include that was summarized from a discussion concerning
standards for geological disposal held at an IAEA/WASSAC meeting (Issues related to the preparation ofsafety standards on the geological disposal of radioactive waste presented at IAEA WASSAC
Proceedings of a Specialist Meeting held from 18 to 22 June, 2001)

D−1

Safety case: the following items which should be covered are:a) The implementer should be required to clearly document his/her arguments and supporting
information,b) The safety case should be appropriately constructed bearing in mind the need to convince different
audiences,c) A well-structured approach should be used which allows for the iterative development andimprovement of the safety case as new information becomes available,d) It should be built on the safety assessment and describe the results of the safety assessment,e) It should describe the overall safety strategy and the safety functions of the various barriers,f)

It can be both quantitative and qualitative,g) Uncertainty should be treated explicitly and the implications for repository performance should bemade clear,h) It should make use of multiple lines of evidence or reasoning,i)

It should demonstrate safe repository performance and compliance with regulatory requirements,j)

It should address safety indicators and how they are used,k) It should provide sufficient confidence in safety such that consent can be obtained to move to the next
step in the approval process,l)

It should describe planned work for the future,m) It should address the issues of human intrusion, retrievability and multiple barriers (i.e., if and how
the safety case relies on more than one barrier) andn) It should address the use of deterministic and probabilistic assessment approaches.
Decision-making process:Finally, the safety case and the safety assessment should relate to the decision-making process. It should
be made clear that the context for both the safety case and the safety assessment is a stepwise decisionmaking process. The nature of the safety case and safety assessment should reflect the particular decisionat hand and the decision maker. They should provide a clear indication of the level of confidence which
can be attached to the repository performance and the implementing organization. Context for the resultsof the assessments should be given in terms of the levels of safety provided and the time-scales being
discussed.

D-2

The Status of Monitoring in a Safety Case

A safety case must fully recognize and respect the different levels of knowledge and decision-making capabilityof the various entities who must make judgments and receive information concerning the safety of geologicaldisposal sites. Generally speaking, the receivers of information could fall into the following four groups:-

Site operators and promoters,

D−2

-

Regulators and others on the regulatory side,-

Opinion leaders and-

The general public

The problem is how to appropriately convey proper information to people other than those on the operating side
so as to ensure understanding.
Because people in different positions have different levels of understanding, and because the levels of thecontent to be understood are already different, various methods of conveying information must be used, alongwith different kinds of evidence and grounds for argument. The issues pertaining to these different groups andtheir respective levels of understanding can be summarized as follows.
-

Because different groups have different levels (including the absence) of knowledge and interest in both theoverall picture of geological disposal technologies and their constituent elements, an understanding of theeffectiveness of those technologies is an important, fundamental piece of information. Knowledge about thesoundness of containers, the closure characteristics of other physical barriers, the stability of the bedrock,and similar aspects are important criteria for some people when making safety judgments,-

Mathematical measures such as modeling of future scenarios may not be enough to satisfy the safetyconcerns of some–or indeed most–people. Such people might demand actual demonstrations of safety
rather than logical grounds for argument,-

With regard to guaranteeing safety and sustaining peace of mind, it might be possible to increase
confidence among certain groups of people by introducing contingency measures that would come intoplay in the unlikely event of a serious problem. This approach would lead to enhancing the significance ofmonitoring and retrievability,-

To ensure immediate understanding among all interested parties, grounds for argument concerning safety
must be expressed without using technical jargon,-

It might be necessary to place a high priority on proving the short-term safety of the site (for example, 100
years), which some people show a direct interest in, and-Part of the safety case must deal with the many credible problems and phenomena that attract publicattention.

Approaching the issues from this perspective, monitoring can be given the following status within a safety case.
-Even if specialists judge that leaks of radionuclide are unthinkable within a thousand years, to satisfy
people who worry about leakage planners may feel compelled to develop scenarios in which theunthinkable occurs. If monitoring is implemented, it can clarify leakage conditions and lead to appropriate
countermeasures, thus providing safety guarantee.

-

Even if it is not directly connected to leakage, monitoring can provide a warning and a grasp of related
phenomena, making it possible to deduce safety levels. When necessary, it can also be tied in with
judgments and countermeasures, or, through linkage with a system that implements countermeasures, it
can provide a safety guarantee.

-

The appropriate construction and maintenance of a monitoring system can itself give people peace of
mind.

-

Through the proper handling and understanding of the technical aspects of monitoring, confidence both inD−3monitoring itself and the disposal system being monitored is increased.
-

Monitoring is one way to "demonstrate safety simply and directly," given as an example of approaches
and methods for safety assessment by OECD/NEA (1999).

Therefore, it is desirable that the content of monitoring should be considered so that it can satisfy the statusrelated conditions cited above.

References
OECD/NEA: Confidence in the Long-term Safety of Deep Geological Repositories – Its Development andCommunication (1999)
Special Advisory Board on High-level Radioactive Waste Disposal Safety of the Nuclear Safety Commissionof Japan, About the way of thinking of Safety Cases (OECD/NEA), (Waste Disposal Reference No. 6-3(Sixth meeting, February 6, 2002)

D−4

Attachment E How Safety Cases Are Handled by International
Agencies

The approaches that have been adopted by international agencies toward safety cases are summarized in Table
E-1 below.
In "Confidence in the Long-term Safety of Deep Geological Repositories–Its Development andCommunication–" (OECD/NEA 1999), which is one of the first reports to advocate safety cases for geologicaldisposal, a "safety case" is considered a superordinate concept that includes safety assessment. It is defined asfollows: "A collection of arguments, at a given stage of repository development, in support of the long-term
safety of the repository. A safety case comprises the findings of a safety assessment and a statement ofconfidence in these findings."
Similarly, the following definition of "safety case" is found in "Scientific and Technical Basis for the
Geological Disposal of Radioactive Wastes" (IAEA Technical Reports Series No. 413, 2003): "A collection ofarguments and evidence to provide reasonable assurance of the safety of a facility or activity. This will usually
include a safety assessment, but would also typically include information (including supporting evidence andreasoning) on the robustness and reliability of the safety assessment and the assumptions made therein."
As these definitions indicate, a safety case is a collection of information “data package” that indicates the safetyof disposal in the form of a written safety assessment. As such, it is supplemented and revised as progress ismade through each disposal step.

References
OECD/NEA：Confidence in the Long-term Safety of Deep Geological Repositories – Its Development andCommunication (1999).
IAEA：Scientific and Technical Basis for the Geological Disposal of Radioactive Waste, Technical Reports
Series No.413 (2003).
IAEA：Geological Disposal of Radioactive Waste，Draft Safety Requirements, DS154 (2002).

E−1

Table Ｅ-1 The Safety Cases of International Agencies (1 of 2)
Agencies
OECD/NEA

References
Confidence in theLong-term Safetyof Deep Geological
Repositories–Its
Development andCommunication–(OECD/NEA,
1999)

Content and Approach of Safety caseComparison of safety assessment and safety case
• Safety assessment
Safety assessment is an evaluation of reliability concerning safety indicated throughlong-term performance, conformity with acceptance guidelines, and assessment
results.
• Safety case
"A collection of arguments, at a given stage of repository development, in support ofthe long-term safety of the repository. A safety case comprises the findings of asafety assessment and a statement of confidence in these findings. It should
acknowledge the existence of any unresolved issues and provide guidance for work
to resolve these issues in future development stages."
Process for Development of safety case(i)

Establish an ASSESSMENT BASIS- define a safety strategy that describes a suitable approach to thebuilding of a safety case,- define the repository site and design (system concept),- assemble the available understanding of the repository system,
together with methods, models and data to evaluate its
performance (assessment capability)(ii)

Carry out a PERFORMANCE ASSESSMENT- evaluate repository performance for the assessment cases,- assess compliance with acceptance guidelines- carry out sensitivity analyses(iii)

EVALUATE CONFIDENCE in the calculated safety and modify, if
necessary, the assessment basis

Steps (i), (ii) and (iii) define the SAFETY ASSESSMENT(iv)

Compile a SAFETY CASE
- document the safety assessment- state confidence in the safety indicated by the assessment- provide guidance for further work in future development stages

Interact with decision makers and modify, if necessary, the assessment basis

E−2Table E-1 The Safety Cases of International Agencies (2 of 2)
Agencies
IAEA

References
Scientific andTechnical Basis for
the Geological
Disposal ofRadioactive
Wastes (IAEA
Technical Reports
Series No. 413,
2003)
Geological
Disposal ofRadioactive
Waste–Draft
SafetyRequirements(DS154)(October 14, 2002)

Content and Approach of Safety caseDefinition of Safety Case (modified definition from the glossary of safety termsof IAEA)
A collection of arguments and evidence to provide reasonable assurance of the safetyof a facility or activity. This will usually include a safety assessment, but would also
typically include information (including supporting evidence and reasoning) on therobustness and reliability of the safety assessment and the assumptions made therein.

Definition of Safety Case

§5.5. The safety case is a collection of arguments and evidence that describe,
quantify and substantiate the safety, and the level of confidence in the safety, of theradioactive waste disposal facility. The safety case is an essential input to all theimportant decisions about the facility. It will include the output of safety assessments(see below) and additional information, including supporting evidence and reasoning,on the robustness and reliability of the facility, its design, the design logic and the qualityof safety assessments and its underlying assumptions. The safety case may also
include more general arguments related to the need for radioactive waste disposal,
and information to put the results of the safety assessments into perspective. The
safety case should acknowledge the existence of any unresolved issues at any
particular step in the development of the facility and provide guidance for work to
resolve these issues.
Definition of Safety Assessment§5.6. Safety assessment is the process of making systematic analyses of theradiological hazards associated with the disposal facility, and of the ability of the design
to provide the safety functions and meet technical requirements. It will include
quantification of the overall level of performance, analysis of the associateduncertainties and comparison with the relevant design requirements and safety
standards. Safety assessments should also identify any significant deficiencies inscientific understanding: data or analysis such as might affect the results presented.
Depending on the stage of development, safety assessments may aid in focusing
research, and their results can be used to determine compliance with internal orexternal safety goals and standards.
Requirements for the Safety Cases and Safety Assessments
Requirement 11 - Preparation of the Safety Case and Safety Assessments
A safety case and supporting safety assessments shall be prepared and updated, as
necessary, at each step during the development of the disposal facility. These shall be
sufficiently detailed and comprehensive to provide the necessary technical input toinform the decisions needed at each step.
Requirement 12 - Scope of the Safety Case and Safety Assessments
The safety case for a geological disposal facility shall describe all the safety relevant
aspects of the site, the facility design and the managerial and regulatory controls. The
safety case and its supporting assessments shall illustrate the level of protection
provided and shall give assurance that safety standards will be met.
Requirement 13 – Documentation of the Safety case and Safety Assessments
The safety case and its supporting safety assessments shall be documented at a
sufficient level of detail and quality to support the decision at each step and to allow
independent review.

E−3Attachment F Surveys and Analyses Concerning UndergroundResearch Laboratories (URL) in Japan and Abroad

A survey was conducted on the kinds of measurements being made in connection with geological disposal at
Underground Research Laboratories (URL) in Japan and abroad. The results are shown in Table F-1.
Each URL is measuring different things for different purposes. For reference, several examples are given belowthat might have a bearing on monitoring.
The (TSX) tunnel sealing experiment carried out at Whiteshell in Canada involved the insertion of sandbetween the plugs of a tunnel at a depth of 420 meters and the evaluation of plug performance by increasingwater pressure. More than 900 sensors were used in the test to measure such factors as temperature, pore waterpressure, pressure, stress, deformation, distortion, and AE (Acoustic Emission). After three years, 90% of thesensors were still working (94% if the installed inside the concrete plug to measure water content are excluded).
In the test, 245 measuring cables with 9.5 mm in diameter were passed through the plug. Because it was known
from previous experience that the cables become water channels, countermeasures were taken such as encasing
the cable bolts with cement grout or using plugs.
In the Prototype Repository Projects (PRP) being conducted in Äspö in Sweden, also, countermeasures havebeen taken to prevent cables used for sensing from becoming water channels.
At the Grimsel Test Site (GTS) a Spanish project called FEBEX is being conducted that involves in situ testingof full-scale engineered barriers. A total of 632 sensors of different kinds are used to monitor the thermo-hydromechanical processes through the measurement of such variables as temperature, total pressure, pore waterpressure, water content, and displacement. Sensors installed in bentonite must be capable of withstanding
temperatures in excess of 100°C, pressures up to 5 MPa, and highly corrosive environments, with a required
service life of three years. Because it was difficult to find sensors on the market that met these requirements, it
was necessary to develop sensors that were specially designed and protected (Enresa, 2000). The instruments
have performed beyond expectation, with just 5.7% of them suffering failure due to reasons other than water
submergence or physical damage. The report states that it is necessary to further extend the service life of all
instruments.
As the above URL experiences indicate, certain sensors can be expected to function for several years ingeological disposal environments, but the extension of their service life is a topic of future concern. Also,
countermeasures are needed to prevent the cables used for sensing that transmit sensor data from acting as water
channels.

References
ENRESA：FEBEX project. Full-scale engineered barriers experiment for a deep geological repository for highlevel radioactive waste in crystalline host rock. Final report, PT-01/00 (2000).

F−1Table F-1 Overview of objects, major testing and methodologies of URL in various countries (1 of 4)

URL

Objects, Remarks

Main experiments
and parameters
related tomonitoring in URL

F−2
Methodologies,
equipments

SwedenFinlandFranceSwitzerlandÄspö Hard Rock Laboratory（Äspö）

Olkiluoto (candidate site)

Bure (Under construction)

Grimsel Test Site (Granite)

To provide the scientific and technical basis for thework of siting, design, construction and operationof a future geological underground repository
facility; construction began in 1990; operating since
1995.
Prototype repository projects (PRP)・ Temperature evolution of canister, buffer,
backfill and rock・ Hydrogeology of near field rock・ Deformation and stress in near field rock・ Coupling of temperature, hydrogy andmechanic
・ Resaturation in buffer and backfill
・ Porewater pressure evolution in buffer,
backfill and rock・ Swelling pressure evolution in buffer, backfill
and rock・ Deformation of canister
・ Gas composition in buffer and backfill
・ Chemical composition in Porewater in buffer
and backfill and water in near field rock
Borehole monitoring・ Groundwater level・ Hydraulic pressure
・ Electrical conductivity
・ Groundwater chemistry
・ Atmospheric pressure
・ Sea level・ Rainfall and air temperature on Oskarshamn
・ Temperature: Fiber optics; thermocouple
・ Total pressure, pore pressure: Vibrating string;fiber optics
・ Displacement of canisters: Strain gauges
mounted on extensometer-type sensors; strain
gauges・ Hydraulic conductivity: Piezometer・ Water content: Capacity (RH); psychrometer・ Groundwater level, groundwater pressure:hydraulic multiplexer; pressure transducer
・ Groundwater electrical conductivity: ECsensor;
electric conductivity meter・ Barometric pressure: stand alone data logger(BORRE)・ Sea level: Writing recorder is connected to afloat in a gauge well

Tunnel adjacent to the Olkiluoto repository for
LLW; Characterization and detailed planning of
the selected site are scheduled for completion by
the end of 2010 and work on building the facility
will begin after that.
Geological survey
・ Rock characteristics (magnetic susceptibility;
natural gamma-ray; rock density; neutronback scattering; fracture characteristics)
・ Groundwater flow in borehole・ High permeable fracture frequency
・ Rock characteristics surrounding borehole
Monitoring in research tunnels
・ Detailed geological mapping of the tunnel
surface・ Surveying of tunnel surface, location of
fractures, and half barrels of blast holes
・ Mapping of excavation damage on halfbarrels of blast holes
・ Determination of mechanical properties of
the rock・ Ground penetrating radar on the floor of thetunnel・ Inflow mapping
・ Structural modelling

Under construction; shaft sinking phase; surface
exploration 1999; access construction andunderground exploration 2000; shaft sinking from2000 to 2002; examinations in gallery from 2003 to2006.
Deep borehole monitoring
・ Various borehole data (total natural gamma
radiation; deep resistivity; density of theformation and the photoelectric factor; porosity;
diameter of the borehole with the caliper;
hydraulic-head recovery; temperature; tests
depending on permeability with measurement
and acquisition of flow rate, level andtemperature parameters)
Hydrogeology
・ Porewater pressure
・ Suction,
・ Water content
・ Water HeadRock Mechanics
・ Initial state of rock stress・ Rock deformation
Groundwater Geochemistry
・ Geochemical parameters (content of major
ions; dissolved oxygen; pH; Eh; PCO2; electric
conductivity etc)
・ Temperature

Demonstration and assessment of a repository
concept; operating since 1983; GTS Phase IV(1994 –1996); GTS Phase V (1997-2002)

・ Hydraulic properties: single-hole technique・ Rock properties: hydrophysical logging;
Seismic tomography
・ Inflow measurement in the investigation
boreholes
・ Monitoring surrounding boreholes: radar
techniques; VSP; HSP
・ Surface roughness profiling of borehole: Lazar
profilometer
・ EDZ in deposition holes: He-gas techniques;C-14-PMMA・ Borehole data: Various logging
・ Porewater pressure: Piezometer・ Suction: Capacitive hydrometer・ Water-content: Neutron logging
・ Groundwater level: Limnimeter; MADO;THALIMEDES・ Initial state of rock stress: Hydraulic fracturing
test
・ Rock deformation: Vibrating-wire sensor
・ Groundwater chemistry: with specific electrodes
・ Temperature: Metal thermocouple platinumprobes; electromagnetic-pressure gauge (EPG)

・ Hydraulic properties: Surface packer; Shortinterval packer / combined packer system;
MMPS system Slim Hole Piezometer Systems;
Mini-Sonic Probe
・ Water content profiles in matrix: TDR
・ Geomechanical properties: Mini-Sonic ProbeGTS Phase IV (1994 –1996):
1. Seismic Tomography (TOM), aimed atclarifying the potential of this method for remote
identification of structures in the rock.
2. Borehole Sealing (BOS), with the emphasis on
testing sealing technologies for long,subhorizontal boreholes.
3. Radionuclide Retardation Project (RRP),
focusing on validation of sorption and matrix
diffusion models.
4. Full Scale Engineered Barriers Experiment(FEBEX), aimed at demonstrating waste
emplacement technologies for high-level waste.
5. Tunnel Near-Field Programme, the study for acrystalline rock environment the relevance ofthe tunnel near-field as a key issue for
performance assessment.
・ EDZ (Excavation Disturbed Zone)
・ ZPK (Two-Phase Flow in Fracture
Networks)
・ ZPM (Two-Phase flow in Rock Matrix)
・ TPF (Two Phase Flow in Shear Zones)

Table F-1 Overview of objects, major testing and methodologies of URL in various countries (2 of 4)

URL

Objects,
Remarks

F−3

Main experiments
and parameters
related tomonitoring in URL

Methodologies,
equipments

Switzerland

Belgium

Spain

UKMont Terri Tunnel（Opalinus Clay）

HADES research facility (Mol)FEBEX (Grimsel Test Site)

Rock Characterisation Facility (Sellafield)

To investigate the geological, hydrogeological,
geochemical and rock mechanical propertiesof the Opalinus Clay formation and to provide
input for assessing the feasibility and safety ofa repository for radioactive (or chemotoxic)
waste in this type of host rock; gallery from ahighway tunnel, initiated 1995.

To in situ measurements and large-scale integrated
experiments; shaft sinking began 1980, operating since 1984and extended 1998-9

Full-scale Engineered Barriers EXperiment; To study
the behavior of the near-field components for a highlevel waste (HLW) repository in crystalline rock; The
project initially scheduled for 7 years (1994-2001) has
been extended to 2003.

Mont Terri Research Programme:
・ Flow mechanism (fluid logging)・ Flow mechanism (tracer)・ Groundwater sampling (in situ)
・ Borehole fluid effects
・ EDZ Hydraulic and pneumatic tests
・ EDZ geophysical characterization
・ EDZ self-healing・ Osmotic pressure
・ High-pH Cement porewater
・ Diffusion in rock・ Migration in main fault zone
・ Heater experiment・ Porewater pressure
・ Horizontal raise boring・ Small diameter disposal drift
・ Deep borehole simulation

Specific Experiments in HADES:PRACLAY (Preliminary demonstration test for Clay
disposal of high radioactive waste)・ Demonstration of the feasibility of construction andoperation using techniques that would have to be
dealt with for the repository;・ Erection and support a large connection chamber;・ Monitoring of the thermal, hydraulic and mechanicalbehaviour of the clay layer, gallery concrete lining,filling material and metal shroud surrounding thedummy waste.
CERBERUS (Control Experiment with Radiation of theBelgian Repository for Underground Storage)
・ Direct demonstration of combined effects of radiation,
heat and drilling (local HLW near-field)
RESEAL (The Large-scale in situ sealing demonstration
test)
・ Demonstration of the installation techniques of sealingmaterial and optimization the installation techniques by
the use of pre-compacted pellets
CORALUS (Corrosion of Active Glass in Underground
Storage Conditions)・ Performance study of active HLW glass specimens ina geological disposal site in the Boom Clay formation
CLIPEX (Clay Instrumentation Programme for the
Extension of an underground research laboratory)
・ Modelling and monitoring of the hydro-mechanicalresponse of the clay during excavation of theconnecting gallery
・ Radiation level (CERBERUS): Ionization chamber and
LiF dosimeters
・ Evolution of temperature of rock: Thermo-probes
・ Porewater chemistry (pH, Eh): pH sensor; sampling
analysis・ Total pressure on the host clay / lining outer face:pressure transducers; pressure cells
・ Water pressure (or suction) in the plug / host clay:
Piezometers

The project consists of:・ An 'in situ' test performed under natural conditions
and at full scale;・ A 'mock-up' test, at almost full scale, and・ A series of laboratory tests to complement the
information from the two large-scale tests
Variables measured are:・ Temperature
・ Humidity
・ Stress・ Total pressure
・ Displacement
・ Water pressure
・ Generation and transport of gas

A site investigation began at Sellafield in
1989; Nirex planning application for an
RCF (Rock Characterisation Facility) at
Sellafield was rejected following a Public
Inquiry, held between September 1995
and February 1996; All site works andmonitoring equipment have been
removed, and all site investigation
boreholes have been permanently
abandoned.
The monitoring items measured in
Sellafield;
・ Groundwater pressures
・ Groundwater temperature
・ Atmospheric pressure
・ Stream flow data

・ Hydrogeology: Injection of fluorescenetracered resin into the rock, overcoring anddetection of flow paths filled with resin;Packer-test
・ Hydrochemistry: Groundwater sampling
and analysis; squeezing and leaching ofrock samples
・ Evaluation of the influence of various fluids
on borehole stability: Monitoring of fluid・ Temperature: Thermocouple
・ Total pressure in borehole in rock (3-D): Vibratingwire
・ Total pressure on heater: Vibrating wire・ Hydraulic pressure in borehole in rock:Piezoresistive
・ Packer pressure in borehole: Piezoresistive・ Pore pressure in bentonite: Vibrating wire・ Water content: Capacitive; Psychrometer; TDR・ Groundwater pressures: Pressuretransmitters,
・ Groundwater temperature:
Temperature measurement devices
・ Stream flow data: River and stream
gauges,Switzerland

Belgium

salinity and caliper in boreholes filled withdifferent fluids
・ Hydraulic parameters of the EDZ:
Hydraulic tests with various equipment
・ Geophysical parameters of the EDZ:
Measurements of the seismic velocity
profile in the EDZ with various tools andtechniques
・ In situ stress: Stress measurements withthe overcoring and undercoring technique /Stress measurements with the boreholeslotter technique・ Radial displacement in the plug / host clay: Displacement
sensors; Inclinometers; Extensometers
・ Hydration profile in the plug: Thermal conductivity
evolution
・ Stresses in the lining: Load cells (if concrete lining); strain
gauges (if cast iron lining)・ Convergence: Tape extensometers

Spain
・ Extensometer in rock: Vibrating wire・ Heater displacement: Vibrating wire・ Expansion of bentonite block: Vibrating wire・ Displacement within the bentonite barrier:Potentiometer; Clinometer LVDT; Crackmeter
LVDT・ Gas pressure in the bentonite barrier: Magnetic
・ Atmospheric pressure: Piezoresistive・ Resistor intensity / Resistor voltage electric
converterUK

F−4

Table F-1 Overview of objects, major testing and methodologies of URL in various countries (3 of 4)

URL

Objects, Remarks

F−5

Main experiments
and parameters
related tomonitoring in URL

Methodologies,
equipments

Germany

USA (YMP)

USA (WIPP)

Gorleben, Konrad, Morsleben

Yucca Mountain Site

Waste Isolation Pilot Plant (WIPP)

Gorleben: Exploratory work for potential
repository site suspended for 3-10 years bygovernmental moratorium on 1st October 2000;
shafts constructed 1985-1990
Konrad: Galleries in former iron mine; operating
since 1980, in licensing stage for a LLW/ILW
repository.
Morsleben: Former salt and potash mine;
repository for LLW and ILW since 1981

in situ testing began in 1996; construction of an
exploratory side tunnel completed in 1998; underconsideration of monitoring for repository

Operating since 1982; licensed transuranic (TRU)
waste repository since 1999

Parameters monitored:
・ Leveling on surface
・ Convergence measurements
・ Extensometer measurements
・ Inclinometer and incremental extensometermeasurements
・ Settlement measurements
・ Stress measurement
・ Temperature measurements
・ Permeability measurements
・ Micro acoustic emission monitoring・ Humidity and moisture measurements
・ Propagation of moisture in highly compacted
bentonite sealing
・ Location of brine reservoirs
・ Groundwater level
・ Strain sensing
・ pH measurements

Monitoring plan:・ Seepage monitoring;・ In situ package monitoring;・ long-term materials testing;・ ventilation monitoring;・ rock mass monitoring;・ In-drift monitoring;・ Introduced materials monitoring;・ Groundwater level and temperaturemonitoring;・ Surface uplift monitoring;・ Subsurface seismic monitoring;・ Groundwater quality monitoring
Performance confirmation testing:・ Recovered material coupon testing;・ Dummy waste package testing;・ Recovered waste package testing;・ Post closure simulation testing;・ Subsurface sampling and index testing;・ UZ testing; near-field environment testing;・ Waste form testing;・ Waste package testing;・ Borehole seal testing; ramp and shaft seal
testing
Under consideration of parameters or instruments
for monitoring in YMP

No information.

・ Leveling on surface: Digital leveler
・ Convergence: electric potentiometers; fiber
optic
・ Extension of rock around tunnel:
Extensometers
・ Inclination and increment of rock: inclinometers;
incremental extensometer・ Settlement: settlement measuring instrumentswith a measuring range of up to 600 mm
・ Stress: Overcoring stress releasemeasurements with biaxial probes;
extensometers; borehole inclusion method
・ Temperature: Pt100 sensors / thermistors; fiber

Geomechanical Instrumentation System:
・ Cumulative deformation: Sonic probe boreholeextensometer; convergence points; wire
convergence points; sonic probe convergence
meters; joint meters; vibrating wire boreholeextensometer; linear potentiometric borehole
・ Cumulative strain: Embedded strain gauges;
spot-welded strain gauges
・ Load: Rock-bolt load cells
・ Pressure: Earth pressure cells
・ Fluid pressure: Piezometers

CanadaWhiteshell Underground Research Laboratory(URL)
To provides inputs for general design of repository
system and safety assessment and demonstratein situ techniques related to disposal; monitoring
during site investigation stage began in 1980
(1980-1984: monitoring system installed; 19812011: measurements); schedules of URL
construction are: surface facilities (1982-1987);
access to underground (1983-1990); investigation
and research (1989-2011); closure anddecommissioning (2011-2014)
・ Buffer/Container Experiment and Isothermal
Buffer/Rock/Concrete Plug Interaction Test
・ Quarried Block Radionuclide Migration Test
・ Grouting Experiment・ Tunnel Sealing Experiment・ Solute Transport in Highly Fractured Rock
(HFR) Experiment・ Solute Transport in Moderately Fractured Rock
(MFR) Experiment・ Mine-by Experiment
・ Excavation Stability Study
・ Solute Transport Excavation Damage Zone
・ Characterization Program・ In Situ Stress Program・ Multicomponent Experiment・ In Situ Diffusion Experiment・ Swelling pressure within the clay bulkhead andat the interface between the clay and the rock;:
Oil pressure indicator; loop dynamometer・ Displacements of the clay bulkhead (clay plug):
linear potentiometers; sonic probe
・ Deformations of the clay bulkhead, rock andconcrete bulkhead: linear voltage differential
transformers (LVDT’s)
・ Moisture content measurement in bulkhead:thermocouple psychrometer; hygrometers;
time-domain reflectometry probes (TDR’s)
・ Pore pressure in the rock and concretebulkhead: Vibrating wire piezometers

Germany
optics・ Permeability: 4-fold packer probe
・ Micro acoustic emission monitoring: Spatiallydistributed geophones
・ Humidity and moisture: Theta-probes; fiber
optics・ Propagation of moisture in highly compacted
bentonite sealing: Theta-probes
・ Location of brine reservoirs: Ground
penetrating radar (GPR)・ Groundwater level: Limnimeter・ Strain sensing: Fiber optics sensor
・ pH measurements: Fiber optics sensor

USA (YMP)

USA (WIPP)

Canada・ Pore pressure in the rock: Packer string
equipment
・ Temperature: thermocouples; thermistors
・ Displacements within the rock: Boreholeextensometers, with LVDT’s
・ Cracking in the rock and concrete bulkhead:
Microseismic (MS) system; Acoustic emission(AE) system
・ Strains in the concrete: Vibrating wire strain
gauges; laser strain gauges; fibre optic strain
gauges・ Water potential or suction within the concrete:
Psychrometer・ Displacement of the concrete-rock:
Electromagnetic displacement transducers

F−6Table F-1 Overview of objects, major testing and methodologies of URL in various countries (4 of 4)
URL
Objects,
RemarksF−7

Mainexperiments
andparameters
related tomonitoring in
URL

Japan

Japan

Japan

Kamaishi
To understand geological properties and acquire data in deep undergroundgeological environment; Galleries in former iron-copper mine; completed in 1998.

Tono
To understand deep undergroundgeological environment (geoscientificresearch); galleries in former uraniummine; operating since 1986

1. Characterization of the deep underground geological environment: Fracture
distribution; age determination; paleomagnetism measurement
2. Geomechanics (excavation disturbance): : in-situ mechanical testing; initialstress measurements (in-situ); initial stress measurements (in room);geophysical exploration; AE measurement; seismic wave measurement;
displacement / deformation measurement
3. Groundwater flow: Permeability testing (PNC's JFT; within loosened zone;
single-hole); Injection testing within tunnel-floor; stress interference testing;groundwater flow analysis
4. Geochemistry: Sampling analysis from surface borehole; sampling researchtechniques from borehole in tunnel
5. Solute transport: in-situ regine injection testing; in-situ cold-tracer testing
6. Earthquakes: Seismic observation; geohydrogical observation
7. Grout: Grouting testing
8. Buffer filling: Excavation of borehole; buffer emplacement experiments
9. Mock-up testing of engineered barrier: Coupled Thermo-hydro-mechanicalexperiments

Hydrogeology
・ Subsurface hydrogical
Investigation
・ Borehole Investigation(-1000m level)
Geochemistry
・ Shallow borehole Investigation(from -100 to -200m level)
・ Deep borehole Investigation(from -200m to -1000m level)
Geomechanics
・ Excavation disturbance testingin Hokunobe NATM tunnel
・ Shaft sinking disturbance testing

Mizunami URL (MIU)
To carry out a wide range of geoscientific researches in order to build a firm scientific andtechnological basis for the research and development of geological disposal, Two 1,000m
deep shafts are on-going and several drifts will be excavated for geoscientific researches
and applicability of engineering techniques will be estimated; This project extends over 20
years.
Schedule for the MIU Construction Site:
Phase I (Surface-based Investigation Phase):・ Conceptualization of geological features such as: upper highly fractured domain;
sparsely fractured domain, and fracture zone along the faults, identified in the graniteof the site;
・ Investigation technology such as QA/QC methodologies of data acquisition in thefields of geology, hydrogeology and hydrochemistry;・ Drilling technique;・ Technique for Water-conducting feature (WCF) identification, and・ Field management system.
Phase II (Construction Phase / Research along with excavation):・ Geological mapping of the main shaft and drift wall;
・ Measurement of inflow rate during the shaft sinking;・ Cross hole hydraulic test on the WCFs;
・ Groundwater sampling from the shaft and boreholes around the shaft, and chemical
analysis of the water sampled;・ Acoustic Emission (AE) measurement and borehole expansion test for excavation
disturbed zone (EDZ) investigation, and・ Hydraulic pressure and hydrochemical monitoring in the boreholes drilled from thesurface around the shaft.
Phase III (Operations Phase / In-situ investigations and experiments at the depth):
・ Geological mapping of the middle and main drifts;
・ Hydraulic interference test focused on a single fracture and a fracture network;
・ Redox experiment in the boreholes drilled from the drift;
・ Geophysical investigations, AE measurements, etc. in the drift for evaluating the
EDZ;・ Tracer experiments focused on the single fracture and fracture zones, and・ Hydraulic pressure and hydrochemical monitoring in the boreholes drilled from thesurface around the shaft.
In Phase I (Surface-based Investigation Phase), the following investigations are
ongoing or planned at the MIU construction site or the surrounding area for surface-based
investigations. Some of them are on-going.
・ Geological mapping;・ Ground geophysics such as seismic reflection/refraction;
・ Shallow borehole investigations;・ Deep borehole investigations at the site;・ Cross hole tomography and hydraulic tests using the boreholes at and around thesite, and・ Groundwater monitoring such as hydraulic pressure and hydrochemistry.

1. Geomechanics (excavation disturbance): Borehole loading test; release of insitu stress method; hydraulic fracturing method; AE / DRA / DSCA methods; PS
logging / radar reflectivity method / elastic wave refraction method / ultrasonicwave pulse measurement; AE measurement; joint-type displacement gauge
2. Groundwater flow: Measurements of porewater pressure and permeability
coefficient etc...
Methodology, 3. Geochemistry: MP (multi packer) system / MOSDAX; sampling by HPG-10
system; redox experiments
equipment
4. Solute transport:・retardation; Overcoring
5. Earthquakes: Distortion gauge
6. Grout: Permeability test; tomographical experiment
7. Mock-up testing of engineered barrier (T-H-M): Thermocouple; water pressuregauge / fracture deformation gauge / Pai-gauge; thermal flow meter /extensometer; earth pressure cell; psychrometer / hydrometer
As of September ,2004

Earthquake Frontiers studies
・ Seismo-electromagnetic
phenomena
・ Earthquake-related water-levelchangesGeochemical sampling
investigation by deep borehole
・ pH
・ Eh
・ Electrical conductivity
・ Sulfide ion content
・ Water temperature
・ Porewater pressure
・ Packer pressure
・ Pressure in sampling cell・ Sampling volume

Radioactive Waste Management Funding and Research Center (RWMC)
4th floor, No.15Mori Building, 2-8-10, Toranomon, Minato-ku, Tokyo, 105-001, Japan
Tel: 81-3-3504-1081 Fax: 81-03-3504-1297,
http://www.rwmc.or.jp