Introduction to the Mizunami URL and details of site visit

Introduction to the Mizunami URL and details of site visit Japan Atomic Energy Agency Crystalline Environment Research Group Geological Isolation Research and Development Directorate Takanori KUNIMARU

Schedule of Geological Disposal in Japan... R&D H3 Report ('92) Feasibility of Geologic Disposal Geoscience Study at Tono Uranium Mine('86~'03) Initiation of R&D on Geologic Disposal Experiments in ENTRY started('93) Geoscience Study at Kamaishi Mine('88~'98) 1981 1976 1986 MIU Project started('96) 1992 Long-term Plan of Atomic Energy Policy Exp s in QUALITY started('99) H12 Report ('99) Technical Reliability of Geologic Disposal Horonobe URL Project started('01) 2010 2000 2040 2030 2020 Technical Basis Continuous Reinforcement of Establish NUMO('00) Waste Disposal Act('00) H17 Report('05) Site Selection National Policy Design, Construction, Operation of Repository Open Solicitation Started( 02.12) Basic Guideline of Regulation on Geologic Disposal Nuclear Safety Committee('00) 2

Conclusion of H12 Report and JAEA s R&D programs H12 report were concluded: Although Japan lies in a tectonically active setting with fairly complex geology, a well-founded understanding of key geological events and processes allows selection of stable areas as potentially suitable sites The fundamental practicality of repository and engineering technology has been demonstrated for several design concepts Integrated performance assessment for defined systems shows that the safety concept is robust, offering large safety margins and having low sensitivity to model and database uncertainties. Current JAEA s R&D program aims to enhance reliability and confidence and its emphasis is placed on: Confirmation on applicability of disposal technologies to specific geological environment at study sites Better understanding of long-term behavior of engineered and natural barriers. 3

Utilities RWMC Relevant organisations of HLW geological disposal in Japan (before the Tohoku Region Pacific Coast Earthquake) Funding Support NUMO Implementation R&D on cost effectiveness Supervision Regulation Government Basic policy Final disposal plan Safety guideline (METI) (NSC) Fundamental technical information JAEA Provide technical basis using URLs and ENTRY, QUALITY JAEA: Japan Atomic Energy Agency NUMO: Nuclear Waste Management Organization of Japan METI: Ministry of Economy, Trade and Industry NSC: Nuclear Safety Commission RWMC: Radioactive Waste Management Funding and Research Center CAO: Cabinet Office 4

Utilities RWMC Relevant organisations of HLW geological disposal in Japan (before the Tohoku Region Pacific Coast Earthquake) Funding Support NUMO Implementation R&D on cost effectiveness Supervision Regulation Government Basic policy Final disposal plan Safety guideline ( METI) ( NSC) Fundamental technical information JAEA Provide technical basis using URLs and ENTRY, QUALITY JAEA: Japan Atomic Energy Agency NUMO: Nuclear Waste Management Organization of Japan METI: Ministry of Economy, Trade and Industry NSC: Nuclear Safety Commission RWMC: Radioactive Waste Management Funding and Research Center CAO: Cabinet Office 5

Reorganisation for nuclear regulation in Japan after the Tohoku Region Pacific Coast Earthquake 6

Geological information of Japan Geologic age of the world URL Geology at EL-500m Horonobe Epicenters in the world (Japan in the mobile belt) Mizunami Crystalline rocks Sedimentary rocks 7

JAEA s R&D Facilities for HLW Disposal Tokai R&D center and Two off-site URLs Tono Geoscience Center Mizunami URL Crystalline rock Fresh water Sapporo Horonobe Underground Research Center Horonobe URL Sedimentary rock Saline water Nagoya Tokyo ENTRY Tokai R&D Center QUALITY Image view Image view ENTRY ; ENginieering scale Test and Research facility QUALITY ; QUantitative Assessment radionuclide migration experimental facility 8

Location of MIU Site Nagoya Kiso River Kyoto JAEA Tono Geoscience Center Kiso River Toki City Toki city legend Tokai Mizunami Gr. City Toki River Mizunami Gr. Toki Granitic body Mizunami city Nohi Rhyolite Sedimentary-metamorphic rocks of the Mino Terrane Fault Geological map of the Tono district (after Itoigawa,1980) MIU construction site Toki City Mizunami City Toki River 9

MIU Facilities Ventilation Shaft (φ4.5m) Sub-Stage Main Shaft (φ6.5m) -300m Research /Access Gallery Electricity distribution facilities (including Emergency electricity generation station) Concrete-mixing plant Hoisting device room MIU office 100m 40m Facilities for effluent treatment -500m Research Stage Constructor s office Soundproof tower for Main Shaft excavation Soundproof tower for Ventilation Shaft excavation -1000m Research Stage (image: subject to change) 10

History of Tono Geoscience Center Year 1962 Event Discovery of outcrop of uranium mineralization by the Geological Survey of Japan 1965 Establishment of Tono Exploration Office in Toki City 1986 Commencement of Geoscientific Research 1991 Excavation of a shaft (No.2 Shaft) for Geoscientific Research in Tono Mine 1992 Commencement of Regional Hydrogeological Study 1996 Commencement of Mizunami Underground Research Laboratory Project 2003 Commencement of excavation of Main and Ventilation Shafts (July) 11

Why was Tono area selected for MIU site? Geological environment: granitic rock body exists in this area Location: Central Japan easy access by train and car And Existence of field exploration office in the vicinity since 1965 and accumulated geological information Therefore Existence of knowledge and experience together with experts and technology in the field of earth sciences 12

Timetable of MIU project Current depth Main shaft:gl-500.4m Ventilation Shaft:GL-500.2m 13

Status for excavating shaft and gallery Already excavated area Excavated area in FY 2011 Excavating and excavated area in 2012 Ventilation Shaft (φ4.5m) -200m Sub Stage -300m Sub Stage Sedimentary rock Main Shaft (φ6.5m) Granite -300m Stage -300m Access/Research Gallery -500m Access/Research Gallery-North -500m Access/Research Gallery-South -400m Sub Stage Vent. Shaft 500.2m GL.-500m Stage Main Shaft 500.4m GL-500m stage had been completed on 30 th July 2012 14

Aims of each phases Phase I: Surface-based investigation Construct models of the geological environmental from all surface-based investigation results that describe the geological environmental prior to excavation and predict excavation response Formulate detailed design concepts and a construction plan for the underground facilities Establish detailed investigation plans for Phase II Phase II: Construction To acquire data on the geological environment by investigations from shafts and drifts and predict the characteristics of the geological environment around the drift To verify predictions made in phase I To evaluate the effectiveness of engineering techniques used for design and construction of underground facilities Establish detailed investigation plans for Phase III Phase III: Operation To acquire data on the geological environment via investigations in drifts To verify predictions made in phase II Demonstration of engineering techniques for deep underground utilisation 15

Step-wise investigations Phase I [Surface-based investigation] Phase II [Construction] Phase III [Operation] (EL:m) 200 Sedimentary rock 0 Granite -200 断層 -400-600 -800-1000 Core Borehole investigation Geological mapping/sampling Borehole investigation -1200 Ventiration Main Fault Reflection seismic investigation Seismic by construction Reflection seismic investigation using the construction effect Geophysical investigation 16

Geological environment model based on the result of Phase I investigation 17

Water level (EL.m) Phase II Investigation Main investigation items, aim and goals are: Estimate geological environment around shafts and galleries Assess applicability of investigation techniques through verification of geological models established in Phase I Measure impact on geological environment during MIU construction Confirmation on applicability of construction techniques No.1, 2 210 Etc. No.3-7 160 170 120 Geological mapping 130 Jun. Jul. Aug. Sep. Oct. Nov. Dec. Time (Month) Long-term monitoring Jan. Feb. Mar. 80 Apr. 18

Existing borehole in the URL Ventilation shaft 換気立坑主立坑 Main shaft -200m M-Niche-V 06MI06 号孔 06MI04 号孔 06MI05 号孔 08MI15 号孔深度 200m ボーリング横坑 ( 換気立坑 ) 08MI14 号孔 08MI16 号孔 07MI10 号孔 ( ひずみ計測 ) 07MI11 号孔 ( ひずみ先行変位計測 ) 07MI12 号孔 ( 先行変位計測 ) 07MI09 号孔 12MI30 号孔 12MI31 号孔 12MI28 号孔 12MI29 号孔 -300m M-Niche-V GL-300m sub stage 深度 300m ボーリング横坑 ( 換気立坑 ) 深度 300m 予備ステージ 09MI19 号孔 09MI18 号孔 09MI17-1 号孔 12MI32 号孔 05MI01 号孔 Water 集水リングcollection ring 深度 100m 予備ステージ GL-100m sub stage 07MI07 号孔 GL-200m sub stage -200m M-Niche-M 深度 200m 予備ステージ深度 200mボーリング横坑 ( 主立坑 ) 10MI22 号孔 09MI20 号孔 07MI08 号孔 09MI21 号孔深度 300m 研究アクセス坑道 08MI13 号孔 10MI24 号孔 10MI25 号孔 10MI26 号孔 10MI23 号孔 GL-400m 深度予備ステージ sub stage -300m A/R Gallery 深度 500m 研究アクセス南坑道 12MI33 号孔 06MI03 号孔 06MI02 号孔 12MI27 号孔深度 500m 研究アクセス北坑道 19

Results of wall mapping investigation Ventilation Shaft Main shaft direction direction pegmatite Fault plane Fault rocks (gouge,fault breccia) fracture Highly fractured, and/or wall rock alteration 20

Conclusion of wall mapping investigation at ventilation shaft Ventilation Shaft Fracture density A lot of the low angle fracture is observed above GL- 300m The density of high angle fracture increase with depth from around GL-250m Total amount of fracture number decrease from GL- 460m conspicuously Fracture direction High angle fractures above GL-300 is roughly NNW High angle fractures below GL-300 is roughly NE Geological history of fractures In many cases low angle fractures seem not to cut the high angle fractures Fracture fillings A fracture fillings are not observed in the almost all of low fractures. But the carbonate minerals are observed in some fractures. The carbonate and clay minerals are observed in the high angle fractures. 21

Definition of flow-path fractures in/around drift at GL-300m Inflow rate (l/min) Large inflow was occurred during the pilot borehole investigation before excavating the drift at GL-300m. Therefore the grout was used during the drift excavation. The fractures filled by grout material is observed in/around grouting area. Flow-path fractures are defined based on the presence or absence of grout material in the fractures: Inflow rate during pilot borehole investigation The Major Flow-path Fracture (Major ca. 1,690l/min FF) is filled by grout material ca. 1,685l/min The Minor Flow-path Fracture ca. 1,200l/min (Minor FF) is not filled by grout material but it is observed a small inflow or wet state. depth(m) Pilot borehole Grout filling fractures Wet fractures Other fractures Grouting point Fracture distribution and inflow rate of the pilot borehole 26

Alteration around the fractures Non-alteration around the fractures Summary -Geological characterisation of flow-path fractures- Fractures covered with carbonate minerals behave as flow-path fracture. Fractures without alteration behave as flow-path fracture. Both facture fillings and alteration around fracture is important to distinguish flow-path fracture. Major FF Minor FF Other fractures I-1 I-2 I-3 Calcite (C-axis growth) Calcite (C-axis growth) Hydrothermal minerals Hydrothermal minerals II-1 II-2 II-3 Calcite (Platy shape) Hydrothermal minerals Calcite (Platy shape) Hydrothermal minerals Conceptual model of relationship between petrography and flow-path fractures 27

Groundwater flow in the fracture 28

Updated geological model at GL-500m stage based on the result in F.Y. 2011 (1) Model updated Updated geological structure (1) Updated geological structure (2) Site_Geo_sh460_prov Site_Geo_sh460 This model was developed based on the result of wall mapping until GL-460m 29

Updated geological model at GL-500m stage based on the result in F.Y. 2011 (2) Model updated Updated geological structure (3) Site_Geo_sh460 Site_Geo_sh500 Site_Geo_sh460 This model was developed based on the result of wall mapping until GL-500m 30

Updated geological model at GL-500m stage based on the result in F.Y. 2012 (3) Model updated This model was developed based on the result of wall mapping until GL-500m and pilot borehole investigations 31

Head(GL-m) Head(GL-m) Head(GL-m) Head(GL-m) Hydraulic pressure monitoring results Tsukiyoshi fault MIZ-1:No.1 without draining M9.0 MSB-3 MIZ-1 180 Shafts MSB-1 160 Surface 140 Neogene D No.1 120 Mudrock 100 unconformity 80 Compartment A No.7 No.1 60 No.2~4 01 02 03 04 05 06 07 08 09 10 11 12 B Time (year) Toki Granite A Main shaft fault MSB-3:No.7 180 160 C 140 120 No.7(EL33.2~17.6m) 100 No.10 80 Compartment B 60 : Monitoring interval 01 02 03 04 05 06 07 08 09 10 11 12 Time (year) MSB-1:No.1~4 Earthquake M9.0 S200_13 MIZ-1:No.10 220 180 160 200 No.1 140 180 No.2 120 100 160 No.3 Compartment D 80 140 No.4 Compartment C 60 01 02 03 04 05 06 07 08 09 10 11 12 01 02 03 04 05 06 07 08 09 10 11 12 Time (year) Time (year) 32

Pumping rate (L/min) Groundwater simulation results The suitability of compartment structures are validated by groundwater simulation Case Hydraulic conductivity (m/s) Toki granite Main shaft f. IF_S200_13 IF_S200_15 IF_SB3_11 IF_SB3_19 Absence of Compartment 3.2E-08 5.0E-11 3.2E-08 3.2E-08 3.2E-08 3.2E-08 Presence of Compartment 3.2E-08 5.0E-11 1.0E-11 1.0E-11 1.0E-11 1.0E-11 0.0 0.2 0.4 0.6 0.8 Amount of pumping Result:Absence of Compartment Result:Presence of Compartment MIZ-1 (No.2: El -26.2m~-83.2m) Result Observation Result 1.0 0 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 Time (day) 250 200 150 100 50 Toki granite Main shaft fault IF_S200_15 IF_SB3_19 IF_SB3_11 IF_S200_13 33

Depth (G.L.-m) Change of chemical condition by long-term monitoring 0-100 -200 Prior to excavation Water collection ring G.L.-200m borehole G.L.-300m borehole G.L.-400m borehole 400 G.L.-200m borehole 300 200 100 400 G.L.-300m borehole 300 No.1 No.2 No.3 No.4 No.5 No.6 200-300 -400 100 400 300 200 G.L.-400m borehole 100-500 0 200 400 Cl - (mg/l) 2007 2008 2009 2010 2011 2012 At first salinity increases due to upwelling of deep saline water, and then it decreases by infiltration of low-salinity shallow water with time. 34

Geological environment model based on the result of Phase I investigation 35

Rock mechanical and hydrochemical investigations in and around closed drift (in Phase III) Aim of drift submerging experiment Realize the recovery process and mechanism of geological environment during facility closure Verify the H-M-C-B simulation methods for recovery process in fractured granite Develop the monitoring technique for facility closure phase and appropriate closure method taking recovery process into account Inclined drift:62m Submerging drift:40m 36

Preliminary result of borehole investigation for the solute transport study collaboration wit CRIEPI (in Phase III) Borehole diameter: 80mm Test interval: 7m In-flow rate: 5l/min Conductivity: K=10-8 (m/sec) In-flow point Predicted fractured zone 37

Preliminary result of borehole investigation for the solute transport study collaboration wit CRIEPI (in Phase III) A fracture connectivity was observed... However, it is not a single fracture. A reservoir effect is very high. In-flow rate from fracture connecting both borehole seems to be different. 38

超過確率 Development of block scale model -Discrete Fracture Network (DFN) Model- Paramers Rlzn. No. Set 1 Set 2 Set 3 Set4 Set 5 Total R01 120,744 25,460 32,998 - - 179,202 R02 115,448 26,550 31,467 - - 173,465 R03 125,504 26,526 29,953 - - 181,983 R04 125,701 24,912 32,006 - - 182,619 R05 123,991 26,392 33,421 - - 183,804 R06 125,057 26,817 32,937 - - 184,811 R07 123,425 27,368 31,707 - - 182,500 R08 125,500 27,177 32,710 - - 185,387 R09 123,510 26,033 31,782 - - 181,325 R10 120,501 25,567 31,680 - - 177,748 Average 122,938 26,280 32,066 - - 181,284 Number of fractures each realisation Set1 Set2 Set3 Set1 Group1 Group2 Set2 Group3 Group4 Set3 Group5 Fracture radius Direction Example 100 10 1 1 3 Set3 0.1 0.01 0.001 Set1 Set2 0.1 1 10 100 1000 Radius m

International Collaboration Information exchange Nagra (Switzerland) KAERI (Korea) Technical training @ KAERI facilities (Korea) Nuclear Researchers Exchange Program (from Vietnam) 40

Thank you very much for your attention 41

Extra 42

MIU Construction Site Tour -Putting on the Protective Equipment- -Jumpsuit Size : SS 5XL -Reflective vest - Socks In your locker -Helmet Fasten the buckle. -Cotton work gloves - Rubber work boots Size: 23.0-30.0 cm -Sneakers Size : 22.0 cm -Locker Key Please leave your valuable stuff in the locker. Cell phone and camera can be attached to the key strap to prevent them from falling. Not allowed to bring something, that might have a risk of falling. You may be asked to wear the dust mask, according to the construction condition. Please feel free to ask JAEA staff, if you have any further questions.

Appropriate Protective Equipment * Helmet PHS Reflex vest * * Jumpsuit Work gloves Rubber work boots (Steel toe) -for location tracking -for emergency PHS will be handed after wearing the jumpsuit *:For surface facility touring

MIU Construction Site Tour Please stay with your designated guides and follow their instructions at all times throughout the tour! Tour : Surface Facilities Effluent treatment facility Scaffold, M- Shaft Hoisting room Scaffold, V-Shaft - 300 m Measurement Niche off V - Shaft - 300 m Stage Tour : 300 m Stage - 300 m Sub Stage - 300 m Access / Research Gallery - 300 m Access/ Research Gallery - 300 m Measurement Niche off V-Shaft

Tour route: 300 m Stage Workers Elevator (Capacity: 10 people) Outward Return MIU Office Steep stairs leading to the elevator Watch where you walk, be caution slick or wet surfaces, steep stairs and tripping hazards. Someone suffers from acrophobia or claustrophobia would better avoid making the tour. If you are pregnant, please do not join this tour.