Nakayama, Masashi; Saiga, Atsushi; Kimura, Shun; Mochizuki, Akihito; Aoyagi, Kazuhei; Ono, Hirokazu; Miyakawa, Kazuya; Takeda, Masaki; Hayano, Akira; Matsuoka, Toshiyuki; et al.
JAEA-Research 2019-013, 276 Pages, 2020/03
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies for geological disposal of High-level Radioactive Waste through investigations of the deep geological environment within the host sedimentary rock at Horonobe Town in Hokkaido, north Japan. The investigations will be conducted in three phases, namely "Phase 1: Surface based investigations", "Phase 2: Construction phase" (investigations during construction of the underground facilities) and "Phase 3: Operation phase" (research in the underground facilities). According to the research plan described in the 3rd Mid- and Long- term Plan of JAEA, "Near-field performance study", "Demonstration of repository design option", and "Verification of crustal-movement buffering capacity of sedimentary rocks" are important issues of the Horonobe URL Project, and schedule of future research and backfill plans of the project will be decided by the end of 2019 Fiscal Year. The present report summarizes the research and development activities of these 3 important issues carried out during 3rd Medium to Long-term Research Phase.
Matsuoka, Toshiyuki; Hama, Katsuhiro
JAEA-Research 2019-012, 157 Pages, 2020/03
The Mizunami Underground Research Laboratory (MIU) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies for geological disposal of High-level Radioactive Waste through investigations of the deep geological environment within the host crystalline rock at Mizunami City in Gifu Prefecture, central Japan. The project proceeds in three overlapping phases, "Phase I: Surface-based investigation Phase", "Phase II: Construction Phase" and "Phase III: Operation Phase". The MIU Project has been ongoing the Phase III, as the Phase II was concluded for a moment with the completion of the excavation of horizontal tunnels at GL-500m level in February 2014. The present report summarizes the research and development activities carried out mainly in the GL-500m stage during Third Medium to Long-term Research Phase.
Miyara, Nobukatsu; Matsuoka, Toshiyuki
JAEA-Data/Code 2019-013, 8 Pages, 2020/01
As part of the research and development program on the geological disposal of high-level radioactive waste (HLW), the Horonobe Underground Research Center, a division of the Japan Atomic Energy Agency (JAEA), is implementing the Horonobe Underground Research Laboratory Project (Horonobe URL Project) with the aim at investigating sedimentary rock formations. This data collection is a compilation of Earthquake observation data acquired in the Horonobe Underground Research Project (Phase II).
Takeuchi, Ryuji; Iwatsuki, Teruki; Matsui, Hiroya; Ikeda, Koki; Mikake, Shinichiro; Hama, Katsuhiro; Iyatomi, Yosuke; Matsuoka, Toshiyuki; Sasao, Eiji
JAEA-Review 2019-014, 30 Pages, 2019/10
The Mizunami Underground Research Laboratory (MIU) Project is being pursued by the Japan Atomic Energy Agency(JAEA) to enhance the reliability of geological disposal technologies through investigations of the deep geological environment in the crystalline host rock(granite) at Mizunami City, Gifu Prefecture, central Japan. On the occasion of the reform of the entire JAEA organization in 2014, JAEA identified three important remaining issues on the geoscientific research program based on the synthesized latest results of research and development (R&D): "Development of countermeasure technologies for reducing groundwater inflow", "Development of modeling technologies for mass transport" and "Development of drift backfilling technology". The R&D on three remaining important issues have been carrying out in the MIU Project. This report summarizes the R&D activities planned for fiscal year 2019 on the basis of the MIU Master Plan updated in 2015 and Investigation Plan for the Third Medium to Long-term Research Phase.
Sakai, Toshihiro; Matsuoka, Toshiyuki
JAEA-Data/Code 2019-007, 29 Pages, 2019/09
Japan Atomic Energy Agency is performing the Horonobe Underground Research Laboratory Project, which includes a scientific study of the deep geological environment as a basis of research and development for the geological disposal of high level radioactive wastes, in order to establish comprehensive techniques for the investigation, analysis and assessment of the deep geological environment in the sedimentary rock. This report summarize numerical data of 3D geological model in regional-scale constructed by Maptek Vulcan.
Kubo, Taiki*; Matsuda, Norihiro*; Kashiwaya, Koki*; Koike, Katsuaki*; Ishibashi, Masayuki; Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Sasao, Eiji; Lanyon, G. W.*
Engineering Geology, 259, p.105163_1 - 105163_15, 2019/09
Rock matrix permeability is mainly controlled by microcracks. This study aims to identify the factors influencing the permeability of the Toki granite, central Japan. Permeability of core samples, measured by a gas permeameter, largely increases in the fault and fracture zones. Although a significant correlation is identified between permeability and P-wave velocity, this correlation is enhanced by classifying the samples into two groups by the Mn/Fe concentration ratio. Thus, lithofacies is another control factor for permeability due to the difference in mineral composition. Moreover, permeability shows significant negative and positive correlations with Si and Ca concentrations, respectively. These concentrations are probably affected by dissolution of silicate minerals and calcite generation in the hydrothermal alteration process. Therefore, a combination of hydrothermal alteration and strong faulting are the predominant processes for controlling permeability.
Onoe, Hironori; Kosaka, Hiroshi*; Matsuoka, Toshiyuki; Komatsu, Tetsuya; Takeuchi, Ryuji; Iwatsuki, Teruki; Yasue, Kenichi
Genshiryoku Bakkuendo Kenkyu (CD-ROM), 26(1), p.3 - 14, 2019/06
In this study, it is focused on topographic changes due to uplift and denudation, also climate perturbations, a method which is able to assess the long-term variability of groundwater flow conditions using the coefficient variation based on some steady-state groundwater flow simulation results was developed. Spatial distribution of long residence time area which is not much influenced due to long-term topographic change and recharge rate change during the past one million years was able to estimate through the case study of the Tono area, Central Japan. By applying this evaluation method, it is possible to identify the local area that has low variability of groundwater flow conditions due to topographic changes and climate perturbations from the regional area quantitatively and spatially.
Tsuruta, Tadahiko; Harada, Hisaya*; Misono, Toshiharu; Matsuoka, Toshiyuki; Hodotsuka, Yasuyuki*
Journal of Oceanography, 73(5), p.547 - 558, 2017/10
The seafloor topography was divided into flat and terrace seafloors based on their topographical features and seabed sediments were distributed in an area that was half a degree of the entire investigation area. The Cs inventory was several tens of kBq/m and the grain sizes (the D50 values) were nearly constant (fine sand) on the flat seafloor. On the terrace seafloor, the Cs inventory was larger than that on the flat seafloor, and the grain size varied from silt to coarse sand. The grain size distributions appear to be influenced by the mean shear stress at the seafloor bottom, and a significant factor in the mean shear stress is thought to be the seafloor topography. Distributions of remarkably large Cs inventories, more than several thousands of kBq/m, are thought to be confined to a small area. Vertical changes in the Cs inventories suggested that the Cs inventories have significantly decreased in large areas of the shallow sea.
Sato, Toshinori; Sasamoto, Hiroshi; Ishii, Eiichi; Matsuoka, Toshiyuki; Hayano, Akira; Miyakawa, Kazuya; Fujita, Tomoo*; Tanai, Kenji; Nakayama, Masashi; Takeda, Masaki; et al.
JAEA-Research 2016-025, 313 Pages, 2017/03
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. This report summarizes the results of the Phase II investigations carried out from April 2005 to June 2014 to a depth of 350m. Integration of work from different disciplines into a "geosynthesis" ensures that the Phase II goals have been successfully achieved and identifies key issues that need to made to be addressed in the Phase II investigations Efforts are made to summarize as many lessons learnt from the Phase II investigations and other technical achievements as possible to form a "knowledge base" that will reinforce the technical basis for both implementation and the formulation of safety regulations.
Miyara, Nobukatsu; Matsuoka, Toshiyuki
JAEA-Data/Code 2017-005, 34 Pages, 2017/03
Japan Atomic Energy Agency (JAEA) is performing the Horonobe Underground Research Laboratory Project, which includes a scientific study of the deep geological environment as a basis of research and development for geological disposal of high level radioactive wastes (HLW), in order to establish comprehensive techniques for the investigation, analysis and assessment of the deep geological environment in the sedimentary rock. This report integrates geophysical logging data obtained from the deep borehole investigations (HDB-1 HDB-11) conducted in the Horonobe Underground Research Laboratory Project (Phase I).
Hama, Katsuhiro; Sasao, Eiji; Iwatsuki, Teruki; Onoe, Hironori; Sato, Toshinori; Fujita, Tomoo; Sasamoto, Hiroshi; Matsuoka, Toshiyuki; Takeda, Masaki; Aoyagi, Kazuhei; et al.
JAEA-Review 2016-014, 274 Pages, 2016/08
We synthesized the research results from the Mizunami/Horonobe Underground Research Laboratories (URLs) and geo-stability projects in the second midterm research phase. This report can be used as a technical basis for the Nuclear Waste Management Organization of Japan/Regulator at each decision point from siting to beginning of disposal (Principal Investigation to Detailed Investigation Phase).
Ono, Hirokazu; Takeda, Masaki; Matsuoka, Toshiyuki
JAEA-Data/Code 2015-021, 52 Pages, 2016/01
HDB-1 to HDB-11 were drilled at Hokushin Area of Horonobe Town, Teshio District, Hokkaido, Japan in order to investigate the characteristic of deep underground. This report summarize the results of the work carried out with the purpose of clarifying the geological, mechanical characteristics from the surface to the deeper part of this borehole.
Koike, Katsuaki*; Kubo, Taiki*; Liu, C.*; Masoud, A.*; Amano, Kenji; Kurihara, Arata*; Matsuoka, Toshiyuki; Lanyon, B.*
Tectonophysics, 660, p.1 - 16, 2015/10
This study integrates 3D models of rock fractures from different sources and hydraulic properties aimed at identifying relationships between fractures and permeability. A geostatistical method (GEOFRAC) that can incorporate orientations of sampled data was applied to 50,900 borehole fractures for spatial modeling of fractures over a 12 km by 8 km area, to a depth of 1.5 km. GEOFRAC produced a plausible 3D fracture model, in that the orientations of simulated fractures correspond to those of the sample data and the continuous fractures appeared near a known fault. Small-scale fracture distributions with dominant orientations were also characterized around the two shafts using fracture data from the shaft walls. By integrating the 3D model of hydraulic conductivity using sequential Gaussian simulation with the GEOFRAC fractures from the borehole data, the fracture sizes and directions that strongly affect permeable features were identified.
Ishii, Eiichi; Matsuoka, Toshiyuki; Saegusa, Hiromitsu; Takeuchi, Ryuji
Nihon Oyo Chishitsu Gakkai Heisei-27-Nendo Kenkyu Happyokai Koen Rombunshu, p.135 - 136, 2015/09
no abstracts in English
Hama, Katsuhiro; Mizuno, Takashi; Sasao, Eiji; Iwatsuki, Teruki; Saegusa, Hiromitsu; Sato, Toshinori; Fujita, Tomoo; Sasamoto, Hiroshi; Matsuoka, Toshiyuki; Yokota, Hideharu; et al.
JAEA-Research 2015-007, 269 Pages, 2015/08
We have synthesised the research results from Mizunami/Horonobe URLs and geo-stability projects in the second mid-term research phase. It could be used as technical bases for NUMO/Regulator in each decision point from sitting to beginning of disposal (Principal Investigation to Detailed Investigation Phase). High quality construction techniques and field investigation methods have been developed and implemented and these will be directly applicable to the National Disposal Program (along with general assessments of hazardous natural events and processes). It will be crucial to acquire technical knowledge on decisions of partial backfilling and final closure by actual field experiments in Mizunami/Horonobe URLs as main themes for the next phases.
Sakai, Toshihiro; Matsuoka, Toshiyuki
JAEA-Research 2015-004, 109 Pages, 2015/06
We update the geologic map and the database of the geological mapping published by Funaki et al. (2005a) and Ota et al. (2007) based on geological survey and topographical analysis data in and around the Horonobe area. There are many geological survey data which are derived from natural resources (petroleum, natural gas and coal, etc.) exploration in and around Horonobe-cho. We also use these data in addition to data in Funaki et al. (2005a) and Ota et al. (2007)'s data. As results of this report, we also construct a digital geologic map and a digital database of geological survey using GIS. These results can be expected to improve the precision of modeling and analyzing of geological environment, and its long-term evaluation.
Matsuoka, Seikichi*; Satake, Shinsuke*; Idomura, Yasuhiro; Imamura, Toshiyuki*
Proceedings of Joint International Conference on Mathematics and Computation, Supercomputing in Nuclear Applications and the Monte Carlo Method (M&C + SNA + MC 2015) (CD-ROM), 13 Pages, 2015/04
The quality and performance of a parallel pseudo-random number generator (PRNG), KMATH_RANDOM, are investigated using a Monte Carlo particle simulation code for the plasma transport. The library is based on Mersenne Twister with jump routines and provides a numerical tool which is suitable and easy-to-use on massively parallel supercomputers such as K-computer. The library enables the particle code to increase the parallelization up to several thousand processes without loosing the quality and performance of the PRNG. As a result, the particle code can use large amounts of random numbers, which results in removing unphysical phenomena caused by a numerical noise.
Yamamoto, Nobuyuki; Matsuoka, Toshiyuki
JAEA-Data/Code 2014-032, 33 Pages, 2015/03
Horonobe Underground Research Center has carried out meteorological observation at Horonobe-cho in northern Hokkaido as a part of the Horonobe Underground Research Laboratory project. The meteorological observation data in Hokushin meteorological station from 2003 to 2014 is compiled in this report. Hourly data, daily data and monthly data are included in the data set, and the data set is recorded on CD-ROM.
Hama, Katsuhiro; Mikake, Shinichiro; Nishio, Kazuhisa; Kawamoto, Koji; Yamada, Nobuto; Ishibashi, Masayuki; Murakami, Hiroaki; Matsuoka, Toshiyuki; Sasao, Eiji; Sanada, Hiroyuki; et al.
JAEA-Review 2014-038, 137 Pages, 2014/12
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and the Phase III in fiscal year 2013. This report presents the results of the investigations, construction and collaboration studies in fiscal year 2013, as a part of the Phase II and Phase III based on the MIU Master Plan updated in 2010.
Sakai, Toshihiro; Matsuoka, Toshiyuki; Amano, Kenji
JAEA-Data/Code 2014-005, 43 Pages, 2014/05
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) at Horonobe-cho in Northern Hokkaido, Japan. One of the main goals of the URL project is to establish techniques for investigation, analysis and assessment of the deep geological environment. As a part of this URL project, we develop the geological environment modeling technique. 10m grid digital elevation model (DEM) had been published by Geographical Survey Institute in 2008. The use of 10m grid DEM has made possible examination of detailed topographical features in wide area. We created eighteen kinds of filterd image data using 10m grid DEM around the Horonobe-cho to obtain the basic information for evaluating topographical and geological features and constructing the geological environment model.