Tono Geoscience Center

　　　　Japan Atomic Energy AgencyTono Geoscience CenterSector of Nuclear Fuel, Decommissioning and Waste Management Technology Development　　https://www.jaea.go.jp/04/tono/index.html

〈Mountains and Rivers in Tono region〉

Mt. NorikuradakeMt. Ontake Mt. Kisokomagatake

Mt. Kasagi

Kiso River

Mt. Byobu

Toki River

Mt. Ena

Mizunami Underground Research Laboratory

Toki Geochronology Research Laboratory

2020.4

Facilities of Tono Geoscience Center

Exit toToki-minami Tajimi

Tono Mine

Toki River

Hiyoshi River

Toki City

Mizunami City

③ AMS building

Boundary of the site

Mizunami Underground Research Laboratory

Development of investigation technologies for the long-term stability of the geological environment, and geological models for long-term estimation and effective assessmentDevelopment of dating methods using high-precision mass spectrometers

Development of dating methods, such asoptically stimulated luminescence/thermoluminescence (OSL/TL)Quantitative analysis of the main and trace elements in volcanic glasses and minerals

Development of dating methods using accelerator mass spectrometer (AMS)

Analysis of metallic elements and anions in rocks and waterSample preparation

① Research building

② Instrumental analysis building

③ AMS building

④ Administration building

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①②③

④

Tokai-Kanjo Expressway

Border between Toki and Mizunami cities

④ Administration building

① Research building

Toki Geochronology Research Laboratory

② Instrumental analysis building

Shobasama Site Mizunami Geoscience Academy

19ROUTE

National Route

21ROUTE

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Chuo Line

Chuo Expressway

Toki Junction

Exit toMizunamiExit to

Toki

National Route

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Tokishi Sta.

Mizunami Sta.

Boundary of the site

2020.4

Tono Geoscience Center is pursuingGeoscience Research

What is the geological disposal?

In Japan, the spent fuel from nuclear power gen-eration is reprocessed andseparated into reusable uranium and plutonium and HLW. Uranium and pluto-nium are recovered and recycled as fuel to gener-ate electricity. This cycle of efficient nuclear fuel use is called "nuclear fuel cycle".

HLW is highly radioactive. Although its radioactivity decays with time, HLW continues to release radiation for a long time. Therefore, it is necessary to isolate and dispose HLW from the human environment. Various methods of HLW disposal have been considered worldwide. However, geological disposal is universally recognized as the most promising method because of its technical feasibility. In Japan, the HLW will be placed at a depth of at least 300 m in accordance with the law.

Uranium mining

Nuclear power generation

ReprocessingNuclear Fuel Cycle

Spent fuel

Vitrification (HLW)

Uranium･Plutonium

Fuel processing

Intermediate storage

Geological disposal

The Tono Geoscience Center has been conducting scientific research on the deep under-ground environment, and this is called "geoscience research". This research focuses on understanding the features and long-term stability of the deep underground environment as a part of research and development (R&D) related to the geological disposal of high-level radioactive waste(HLW) produced by nuclear power generation process.

Source: Nuclear Waste Management Organization(NUMO) in Japan

Image: Geological Disposal Facility

Surface facility

Underground facility

2020.4

??

?

Engineered barrier system

Natural geological barrier: keeps the radioactive waste isolated

To ensure the safety performance of geological disposal, research from various perspectives related to deep underground has been conducted.

Could humans disturb radioactive waste while mining

coal and oil?

Could the radioactive waste

leak into groundwater and

migrate to the environment?

Could the

radioactive waste be

uplifted to the surface by

volcanic and seismic

activities?

The repository site

should not be located

in any areas affected by

significant natural

events, such as volcanic

or seismic activities.

The repository site

should not be

located in any area

with potentially

natural resources.

Buffer material (Compacted clay based)

Overpack (Steel container)

Geoscience research being pursued at Tono Geoscience Center

Study on long-term stability of geological environment

Concept of Safety Assurance of Geological Disposal

Vitrified waste（HLW: high-level radioactive waste）

Climate and sea-level changes

Uplift and denudation/Erosion and deposition

Volcanic and hydrothermal activities

Seismic and fault activities

Repository

1

2

2020.4

Toki Geochronology Research Laboratory

The Toki Geochronology Research Laboratory has been conducting a “Study on the long-term stability of the geological environment” to provide scientific knowledge and the investi-igation and evaluation technology required for the geological disposal project and national safety regulations

《Role of Toki Geochronology Research Laboratory》With the aim of further improving the safety measures of the nuclear facility, including geological disposal, the Toki Geochronology Research Laboratory conducts research on the creation of new scientific knowledge and the estimation, and evaluation of the mid-to long-term risks of natural disasters.

Study on long-term geological stability

③Development of dating methodDevelopment and improvement of dating methods, including the radiometric dating method using advanced equipment

① Development and systematization of an investigation technology

Development of technology for investigating pastand present geological events

② Development of models for long-term estimation and effective assessment

Development of methods for the estimation and assessmentof the geological changes caused by future geological events

（Site Selection） （Engineering measures ・Safety assessment）

Consideration on the geologicalcharacteristics in Japan

Japanese islands are located in the Circum-Pacific Mobile Belt, where seismic and volcanic activities occur frequently

Disturbance of the isolation functionof the geosphere

Isolation failure scenarios(e.g. magma intrusion → radionuclide release)

Groundwater flow change associated with natural phenomena

Groundwater scenario(e.g. crustal changes→mountain uplift→ flow rate increasing)

Measures

Impacts on long-term safety of geological disposal

Engineered barrier

Rock mass

Natural geological barrier

Establishment of comprehensive research base focused on geoscience

Scientific and technical knowledgeEarthquake resistance of nuclear facilities Safety of geological disposal Characterization of natural disaster

Toki Geochronology Research Laboratory

Coordination and cooperation within JAEA

Research contract

Research results

Joint research

Universities/Research institutes

Private business operators

Ministry/Regulatory agencies

Relevant divisions Nuclear safety research center

Select ion of a geological environment with a long-term stability to ensure that the performance of the geological disposal system is protected

Design and installation of the engineered barrier system, taking into account the possible natural phenomena and long-term safety assessment of the system

Creation of the latest geoscientific knowledge as a base of safety mea-sures for nuclear power, including geological disposal, and the estimation and evaluation of the mid to long-term geological risks of natural disaster

Development and system-ization of an investigation technology

Development of models for long-term estimation and effective assessment

Development of dat ing methods

Research contract

Research results

Development of dating methods using advanced equipment for instru-mental analysis and standardization of dating methods

2020.4

Study on Long-term Stability of Geological Environment

Development and systemization of an investigation technology with the aim of developing the technical basis to acquire data necessary for site selection.Technology is being developed to understand the rates and ranges of geological change caused by natural events, such as seismic and fault activities, volcanic and igneous activi-ties, and uplift and erosion.

① Development and systemization of investigation technology

〇 Investigation technology for evaluation of fault activities （Development of dating methods focused on the filling minerals along faults）

TEM analysis

Measurement of 40Ar Grain size analysis Measurement of KProcedure to date the filling minerals using K-Ar dating method developed by JAEA

〇 Investigation technology for high-resolution imaging of crustal heterogeneity （Development of technology for detecting underground structure, magma, and geofluids）

■Seismic wave tomography

Low← →HighSeismic wave velocity

Depth: 40kmDepth:25km

Authigenic clay mineral (Mica)

Hot water

Upper plate

Lower plate

Fault gouge sampleHigh-precision separation

K-Ar dating method

Mineralogical analysis

Fault

Sample crushing by freezing and thawing

High- speed centrifugation

Minerals of clastic rock

2020.4

Study on Long-term Stability of Geological Environment

To evaluate the long-term safety of geological disposal for the next tens of thousands of years, scenarios of potential impacts on the geological environment due to natural events should be considered.The development of models for long-term estimation and effective assessment aims to produce methods showing the probability of occurrence of the scenario and ranges of change in the geological environment, including uncertainties in the estimation results.

② Development of models for long-term estimation and effective assessment

〇 Technology for understanding geo-environment changes depending on timescale （Development of a reconstruction technology of past landforms using a numerical simulation）

Visualization from topographic change modeling

Simulation results： Actual terrace distribution

https://www.jaea.go.jp/04/tono/gsp/kashika_kaisetsu_tono.html

Changes in sediment attitude during the last 15,000 years (equivalent to the distribution of the lower terrace)

Higher surface

Three million years ago

One million years ago

Two million years agoKiso River

Toki River

Present

Toki RiverToki River

Kiso River Kiso River

Mt. Byobu

Mt. Kasagi

Ena mountain range Mt. Byobu

Mt. Kasagi

Ena mountain range

Middle surface

Lower

This study was conducted under a contract with METI as part of its R&D supporting program for developing the geological disposal technology.Source: Development of Evaluation Technology for Long-term Geosphere Stability, FY2017 report on Geologic Disposal Project of Radioactive Waste

2020.4

Study on Long-term Stability of Geological Environment

③ Development of dating methodsThe technical development for chronological studies is being performed using various equipment, including mass spectrometers, to understand geological events, such as fault activity and volcanic and igneous activities that are subjected to “study on the long-term stability of the geological environment" and estimate the wide range of geological ages.For example, the depositional ages of sediments can be determined by measuring carbon isotopes (12C, 13C and 14C: same elements with different mass numbers [neutrons]) extracted from plant fragments in sediments using an accelerator mass spectrometer (AMS). In addition, the cooling process of magma can be revealed, and hinter-land, where sediments originate, can be estimated by dating minerals in igneous rocks, such as zircon, using laser ablation inductively coupled plasma mass spectrometer (e.g., U‒Pb method).

<R&D Status of dating methods>

U

PbU

U

U

U

U

Pb

PbPbU

U

U U

Age can be determined by the abundances of parent and daughter isotopes in zircon

Elapse of time

Uranium (U)-lead (Pb) dating methodMethod based on uranium decay to lead with time

Zircon crystallized in magma

Present

When the zircon crystalized

Laser ablation inductively coupledplasma mass spectrometer

Laser ablation system（Photon-machines; AnalyteG2）

Inductively-coupled plasma mass spectrometer（Thermo Scientific; Neptune-Plus）

Mass spectrometry of rock and mineral samples fine grained(aerosolized) by laser ablation

技術開発の対象年代範囲（National Electrostatics Corp.; 15SDH-2）

Target nuclides for dating

14C

10Be26Al 36Cl

129l

Tandem accelerator

Ion source for gas sampleIon source for solid sample

Multi Faraday cup

Ionization detectorAnalyzing magnet

Sequential injection system

Accelerator mass spectrometer（JAEA-AMS-TONO-5MV）

Equipment

Accelerator mass spectrometer (AMS)

Noble gas mass spectrometer

Quadrupole mass spectrometer

Optically stimulated luminescence measurement device

Electron spin resonance deviceHigh precision noble gas mass spectrometer

Electron probe micro analyzer

Laser ablation inductively coupled plasma mass spectrometer

Dating method

14C10Be26Al36Cl129I

K-Ar

(U-Th)/He

OSL

ESRNoble gas

CHIME

U-Pb

Measurable dating period (year)109 Reflected in Target material Present status

Fault activity

Erosion rate

Groundwater age

Uplift rate

Provenance analysis

Provenance analysisCarbonate

Groundwater, Organic

Groundwater

Quartz

Authigenic clay mineral (Mica)Apatite, Zircon

FeldsparQuartz, Carbonate

Monazite, Zircon

Zircon

Practical use

Under development

Fault activity

Fault activity

Fault activity

Fault activity

Erosion rate

Erosion rate

Groundwater age

Groundwater age

Quartz

Quartz

Groundwater

Groundwater

Under development

Practical use

Practical use

Practical use

Practical use

Practical use

Practical use

Practical use

Practical usePractical use

Practical use

Practical use

Target measurement range

108 107 106 105 104 103

2020.4

Mizunami Underground Research Laboratory

At the Mizunami Underground Research Laboratory (MIU), research and development are being pursued with a focus on the critical issues from FY 2015, and satisfactory results have been achieved.Based on this situation, the research and development of the MIU Project were completed at the end of FY 2019.The MIU Site is the property leased from Mizunami City. To complete the removal of facilities by its expi-ration date of leasehold period in January 2022, works, including the backfilling of the underground facility, are under way.

FY 2019 FY 2020 FY 2022-FY 2025 FY 2026 FY 2027

Research based on MIU project

Backfilling ofunderground

facility

Removal of surface facility

Removal of concrete foundation

Environmental monitoring of groundwater

Investigation on environmental impacts around

MIU Site

Opera

tions

（Preparatory work）

FY 2021

Expiration date of leasehold period (January 2022)

(land leveling)

Verification of the effectiveness of themonitoring system（demonstrative experiment）

※

※Groundwater pressure monitoring and water sampling have been performed with surface boreholes since the establishment of the MIU.

Implementation plan of backfilling and removal of facilities

Image: End of March 2028 (after land leveling)

October, 2019

Boundary of the

MIU Site

Image: January 2022（after completion of backfilling and removal of facilities）

The MIU Site will be returned to the municipality at the end of the leasehold period (January 2022). Environmentalmonitoring after backfilling will be conducted at a part of the site under a new land lease agreement.

2020.4

Mizunami Underground Research Laboratory

To understand the recovery of groundwater conditions and environmental impact during and after backfilling of the underground facility, the environmental monitoring of groundwater is being performed during and for five years after the backfilling.

Environmental monitoring of groundwater in surface and underground boreholes

Backfilling will be conducted with verifying the effectiveness of moni-toring systems for water pressure monitoring and sampling

Water pressure monitoring and sam-pling will be performed with the moni-toring systems that demonstrate effec-ctiveness (approx. for 5 years)

After backfillingD

uring backfilling Borehole: Water pressure (level) monitoringinclined borehole: Water pressure (level) monitoringBorehole: Water sampling

05ME06

<Location of monitoring boreholes>

Continuation of water quality analysis of river water and noise and vibration measurement performed since e s t a b l i s h -ment of MIU

500m depth

400m depth

300m depth

200m depth

100m depth

Main ShaftVentilation Shaft

Main ShaftVentilation Shaft

500m depth

400m depth

300m depth

200m depth

100m depth

Assessment of environmental impact around MIU Site

Water pressure monitoring and sampling will be performed during and for five years after the backfilling

Optical fiber sensorSampling tubeBoreholesWater samplingWater pressure monitoringWater pressure monitoring and water sampling

Optical fiber sensorSampling tubeBoreholesWater samplingWater pressure monitoringWater pressure monitoring and water sampling

Environmental monitoring of groundwater

Main Shaft

Ventilation Shaft

2020.4

Tono Mine

Information Transmission and Public Outreach Activities

Head frame

Deposit treatment house

Effluent treatment system

Muck dumping site

Administration building of Tono Mine Shaft hoist house

<Before facility removal>

The Tono Mine excavation began in 1972 with the purpose of characterizing uranium deposits. Geoscience research, including the study on the solute transport in rock mass focused on sedimentary rock, has been conducted since 1986.The examination on the closure activities of the Tono Mine was started in FY 2004. The closure activities have actually been implemented since FY 2010.The backfilling of mine drifts, including three shafts, was completed in FY 2014. The removal of the main surface facilities and the muck dumping site was conducted in FY 2015 and 2016. To ensure safety around the mine, environmental monitoring was performed for about 5 years after the backfilling and completed with confirmation by external experts in FY 2019.In addition, along with continuing management of mineral ore,including uranium bearing materials and excluding the ore produced in the Tono MIne, the effective utilization of the mineral ore, including the mineral ore stored in the Tono Geoscience Center, has been examined.

<After facility removal>

Publication of JAEA research reportsPaper submission to academic journals

Tour of research facility

Information transmission

Participating in local events

Dispatching of instructors

Public outreach activities

Muck dumping site

2020.4

Access to Toki Geochronology Research Laboratory

To Gifu

To Seto

To Minokamo

To Nagoya

To Ena

Roadside Station Kanitte,

Roadside Station Shino.Oribe

Toki City Hall

Oniiwa National Park

GS

Exit toToki

Toki Junction

Exit to Tajimi Exit to Mizunami

JR Chuo lineTokishi Sta.

Chuo Expressway

Otomi

Shizuki-toge

Exit to Kani-Mitake

KomakiJunction

Exit toToki-Minami TajimiToki PremiumOutlets

N

Polytechnic center Gifu

Gotomaki Smart Exit (Exclusively for ETC.)

Tono Geoscience CenterToki Geochronology Research Laboratory

※5 min drive from Exit to Toki

Hana Festa (Flower Festival Commemorative Park)

Toka

i Kanjo

EExpressway

Tom

ei Expressw

ay

■AccessBy public transportation:JR Tokishi Sta. ⇒ Community bus “Minoyaki-danchi Line” (15 min) ⇒ ”Shizuki-toge” bus stop ⇒ (5 min walk) ⇒ Toki Geochronology Research LaboratoryBy Car:Toki I.C., Chuo Expressway ⇒ Turn left at the Exit ⇒ On Route 21 towards Minokamo (5 min)■Contact:

Tono Geoscience CenterSector of Nuclear Fuel, Decommissioning and Waste Management Technology DevelopmentJapan Atomic Energy Agency

Toki Geochronology Research Laboratory959-31, Jorinji, Izumi-cho, Toki-shi, Gifu-ken 509-5102Tel: +81-572-53-0211Mizunami Underground Research Laboratory1-63, Yamanouchi, Akiyo-cho, Mizunami-shi, Gifu-ken 509-6132Tel: +81-572-66-2244

Meishin Expressway