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Ueno, Akio*; Tamazawa, Satoshi*; Tamamura, Shuji*; Murakami, Takuma*; Kiyama, Tamotsu*; Inomata, Hidenori*; Amano, Yuki; Miyakawa, Kazuya; Tamaki, Hideyuki*; Naganuma, Takeshi*; et al.
International Journal of Systematic and Evolutionary Microbiology, 71(2), p.004683_1 - 004683_10, 2021/02
Times Cited Count:6 Percentile:63.69(Microbiology)A novel mesophilic sulfate-reducing bacterium, designated strain HN2, was isolated from groundwater sampled from the subsurface Miocene Wakkanai Formation located in Horonobe, Hokkaido, Japan. The cells were Gram-negative rods, with motility conferred by a single polar flagellum. The isolate expressed desulfoviridin, but no catalase or oxidase activities was detected. Strain HN2 grew in a temperature range of 5-43 C (optimum, 35 C) and in a pH range of 6.5-7.5 (optimum, pH 7.0-7.3). It used sulfate, thiosulfate, dimethyl sulfoxide, anthraquinone-2,6-disulfonate, Fe, and manganese oxide as electron acceptors, but not elemental sulfur, nitrite, or nitrate. The bacterium showed very weak growth with sulfite as the electron acceptor. The strain fermented pyruvate and cysteine in the absence of sulfate, but not malate or succinate. The bacterium did not require NaCl, but tolerated up to 4% NaCl (w/v). Strain HN2 did not require vitamins. The G+C content of the genomic DNA was 56.66 mol%. A 16S rRNA gene sequence analysis showed that the closest recognized relative of strain HN2 is JS1 (97.0% similarity). The average nucleotide identity (ANI) value between strain HN2 and D. JS1 was 79.8%. Based on the phenotypic and molecular genetic evidence, the isolate is assigned to the new species sp. nov. The type strain is HN2 (=DSM 101010 =NBRC 112213).
Fukuda, Kenji; Watanabe, Yusuke; Murakami, Hiroaki; Amano, Yuki; Aosai, Daisuke*; Hara, Naohiro*
JAEA-Data/Code 2020-012, 80 Pages, 2020/10
Japan Atomic Energy Agency has been investigating groundwater chemistry to understand the influence of excavation and maintenance of underground facilities as part of the Mizunami Underground Research Laboratory (MIU) Project in Mizunami, Gifu, Japan. In this report, we compiled data of groundwater chemistry and microbiology obtained at the MIU in the fiscal year 2019. In terms of ensuring traceability of data, basic information (e.g. sampling location, sampling time, sampling method and analytical method) and methodology for quality control are described.
Fukuda, Kenji; Watanabe, Yusuke; Murakami, Hiroaki; Amano, Yuki; Aosai, Daisuke*; Kumamoto, Yoshiharu*; Iwatsuki, Teruki
JAEA-Data/Code 2019-019, 74 Pages, 2020/03
Japan Atomic Energy Agency has been investigating groundwater chemistry to understand the influence of excavation and maintenance of underground facilities as part of the Mizunami Underground Research Laboratory (MIU) Project in Mizunami, Gifu, Japan. In this report, we compiled data of groundwater chemistry and microbiology obtained at the MIU in the fiscal year 2018. In terms of ensuring traceability of data, basic information (e.g. sampling location, sampling time, sampling method and analytical method) and methodology for quality control are described.
Fukuda, Kenji; Watanabe, Yusuke; Murakami, Hiroaki; Amano, Yuki; Hayashida, Kazuki*; Aosai, Daisuke*; Kumamoto, Yoshiharu*; Iwatsuki, Teruki
JAEA-Data/Code 2018-021, 76 Pages, 2019/03
Japan Atomic Energy Agency has been investigating groundwater chemistry to understand the influence of excavation and maintenance of underground facilities as part of the Mizunami Underground Research Laboratory (MIU) Project in Mizunami, Gifu, Japan. In this report, we compiled data of groundwater chemistry and microbiology obtained at the MIU in the fiscal year 2017. In terms of ensuring traceability of data, basic information (e.g. sampling location, sampling time, sampling method and analytical method) and methodology for quality control are described.
Hayashida, Kazuki; Kato, Toshihiro*; Kubota, Mitsuru*; Murakami, Hiroaki; Amano, Yuki; Iwatsuki, Teruki
Chikyu Kagaku, 52(1), p.55 - 71, 2018/03
In this study, the simulated experimental drift was constructed in the granite of 500 m depth at Mizunami Underground Research Laboratory, and the hydrochemical process after the drift closure was observed. The groundwater chemistry around the drift changed with the change of the groundwater flow in the fractures when the gallery was constructed. The redox potential increased due to the infiltration of oxygen from the drift into the rock. After closing the drift, the redox potential of the groundwater plunged due to microbial activity, while the groundwater became alkalized conditon due to the influence of cement material such as shotcrete. The amount of cement material consumed for this alkalization was small, and it was considered that its influence would last long in accordance with the amount of cement used.
Sasaki, Takayuki*; Kokami, Takayuki*; Kobayashi, Taishi*; Kirishima, Akira*; Murakami, Hiroaki; Amano, Yuki; Mizuno, Takashi; Iwatsuki, Teruki; Sasamoto, Hiroshi; Miyakawa, Kazuya
Journal of Nuclear Science and Technology, 54(3), p.373 - 381, 2017/03
Trace amounts of natural thorium and uranium in deep groundwater were investigated at two underground research laboratories situated at Horonobe and Mizunami, Japan. The groundwater was sampled from underground boreholes, and the colloid contribution was checked by in situ two size-fractionated ultrafiltration systems. A decrease in the concentration after in situ filtration suggested the presence of natural colloids and suspended matter that were carriers of a portion of the elements. The result of the Th and U concentrations in groundwater after 10 kDa filtration was analyzed thermodynamically using existing hydrogeological and geochemical data such as the mineral components in the groundwater at a given pH, ionic strength, concentration of co-existing ions, redox potential, and solid phase assumed. A crystalline solid phase made the solubility very low compared with that of the amorphous phase, and the solubility agreed well with the concentrations measured.
Amano, Yuki; Nanjo, Isao; Murakami, Hiroaki; Yabuuchi, Satoshi; Yokota, Hideharu; Sasaki, Yoshito; Iwatsuki, Teruki
Chikasui Gakkai-Shi, 54(4), p.207 - 228, 2012/11
We verified the surface-based hydrochemical investigation for deep underground at Horonobe Underground Research Laboratory (URL) at Horonobe, Hokkaido, Japan, and identified the hydrochemical changes during the URL construction. The evaluation of the relationship between the number of borehole and understanding of water chemistry suggests that three basic borehole investigations and additional borehole for high permeable geological structure (fault and fractured zone) are required to illustrate cross-sectional hydrochemical distribution including the uncertainty in kilometers scale survey line. The observation and numerical analysis of hydrochemical variation (salinity, pH, ORP) around URL indicate that the groundwater pressure and the salinity in the vicinity of high permeable geological zone are varying due to groundwater inflow into the drift. The variation was consistent with the prediction reported previously. These results are considered to be referred to the management during surface-based investigation and construction of underground facility at the other sedimentary rock area.
Nakayama, Masashi; Amano, Kenji; Tokiwa, Tetsuya; Yamamoto, Yoichi; Oyama, Takuya; Amano, Yuki; Murakami, Hiroaki; Inagaki, Daisuke; Tsusaka, Kimikazu; Kondo, Keiji; et al.
JAEA-Review 2012-035, 63 Pages, 2012/09
The Horonobe Underground Research Laboratory Project is planned to extend over a period 20 years. 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). This report summarizes the results of the investigations for the 2011 fiscal year (2011/2012). The investigations, which are composed of "Geoscientific research" and "R&D on geological disposal technology", were carried out according to "Horonobe Underground Research Laboratory Project Investigation Program for the 2011 Fiscal year". The results of these investigations, along with the results which were obtained in other departments of Japan Atomic Energy Agency (JAEA), are properly offered to the implementations and the safety regulations. For the sake of this, JAEA has proceeded with the project in collaboration with experts from domestic and overseas research organisations.
Nanjo, Isao; Amano, Yuki; Iwatsuki, Teruki; Kunimaru, Takanori; Murakami, Hiroaki; Hosoya, Shinichi*; Morikawa, Keita
JAEA-Research 2011-048, 162 Pages, 2012/03
The observation technique of hydrochemical condition in low permeable sedimentary rock around the facility is one of R&D subjects. We report, (1) development of hydrochemical monitoring system to observe water pressure, pH, electric conductivity, dissolved oxygen, redox potential and temperature, (2) hydrochemical observation results around URL under construction. The applicability of the hydrochemical monitoring system is evaluated for low permeable sedimentary rock bearing abundant dissolved gases. The hydrochemical observation during facility construction demonstrates that pH and redox potential of groundwater almost did not changed even at hydraulic disturbed zone (water pressure decreased zone).
Amano, Yuki; Yamamoto, Yoichi; Nanjo, Isao; Murakami, Hiroaki; Yokota, Hideharu; Yamazaki, Masanori; Kunimaru, Takanori; Oyama, Takahiro*; Iwatsuki, Teruki
JAEA-Data/Code 2011-023, 312 Pages, 2012/02
In the Horonobe Underground Research Laboratory (URL) Project, ground water from boreholes, river water and precipitation have been analyzed for the environmental monitoring since the fiscal year 2001. This report shows the data set of water chemistry since the fiscal year 2001 to the fiscal year 2010.
Naganuma, Takeshi*; Iwatsuki, Teruki; Murakami, Yuki; Hama, Katsuhiro; Okamoto, Takuji*; Tanimoto, Daisuke*; Fujita, Yuka*; Watanabe, Fumiko*; Adachi, Nahomi*; Sato, Makoto*
JNC TY7400 2003-001, 116 Pages, 2003/05
The abundance and diversity of groundwater microorganisms was studied in the Tono area, central Japan. Total cell counts were estimated by epifluorescence microscopy. Cell viability, based on cell membrane integrity, respiration-based metabolism, and esterase activity was estimated to be from 0.001% to approximately 100% of the total counts. The distribution of microbial abundance wad related to a variety of environmental factors, including fracture numbers, hydrological, and geochemical conditions in the groundwater. In the groundwater, profiles of redox sensitive solutes such as sulphate and sulphide ions, abundance and viability of microbes, and sulphur isotope rations of sulphate ions suggest that microbial sulphate redution involving organic matter and subsequent pyrite precipiration are dominant redox reactions at the depths of the uranium ore body. Concentrations of both the sulphate and chloride increase with increasing depth. The dissoloved sulphate is surmised to have originated from dissolution of sulphate and sulphide minerals in a geologic marine formation precipitated in marine environments, in the upper part of the sedimentary rocks. Such a redox process in the water-mineral-microbe system is inferred to have continued from the time when the marine formation underwent uplift above sea-level, because sulphate-reducing bacteria can use sulphate ions dissolved in fresh water that infiltrates from the marine formation and organic matter located in the deeper sedimentary rocks. Calculations by using the sulphate-S contents of the rocks and the sulphate dissolution rate suggest that microbial sulphate redution alone could maintain sufficiently reducing conditions of preserve the uranium ore for several hundred thousand years, in the case where a hydrogeological system continues to exist without much change. On the other hand, iron-oxidizing/reducing bacteria seem to play an important role in iron redox cycling in the granite groundwater.
Murakami, Yuki*; Naganuma, Takeshi*; Iwatsuki, Teruki
Genshiryoku Bakkuendo Kenkyu, 5(2), p.59 - 66, 1999/03
None
Murakami, Hiroaki; Amano, Yuki; Nanjo, Isao; Iwatsuki, Teruki
no journal, ,
Constructions such as geological disposal of high-level radioactive waste influence hydraulic and geochemical condition around the facility. Therefore, it is necessary to develop the methodology to evaluate those effects. In this study, we report the results of monitoring for disturbing process of hydrogeochemical conditions of groundwater. Water-collection rings were installed every about 30 m deep in each vertical shafts. The flow rate, physic-chemical parameter (etc. pH, ORP, DO) and chemical composition of groundwater were observed at water-collection rings. Meanwhile, a borehole was drilled at 140 m Niche off the East Shaft. The physic-chemical parameter and hydraulic pressure of groundwater were monitoring at this borehole during drilling of the East Shaft. As a result, it was shown that hydraulic pressure was influenced by drilling the East Shaft in the area from the shaft at least 80 m or more.
Nanjo, Isao; Amano, Yuki; Iwatsuki, Teruki; Murakami, Hiroaki; Sasaki, Yoshito; Yoshikawa, Hideki
no journal, ,
The instrument for groundwater monitoring technique, which can continuously monitor the pore water pressure and physico-chemical parameters(pH, EC, DO, ORP, temp) has developed, to monitor the hydrological and geochemical disturbances caused by underground facility construction. It was able to be confirmed that the pore water pressure decrease in all the observation zone by underground facility construction. The relation between spring water and pore water pressure, physico-chemical parameters will be examined by a consecutive observation.
Murakami, Hiroaki; Amano, Yuki; Kokubu, Yoko; Iwatsuki, Teruki
no journal, ,
C in sedimentary rocks were measured to understand the residence time of groundwater at Horonobe area, Japan. Wakkanai Formation and Koetoi Formation are distributed at the study area. Groundwater samples were collected at -140m and -250m (GL). C concentration in groundwater samples are range from 0.39 to 1.04 pMC. Results of calculations, C in samples are not contamination. Although the C ages are about 40,000 year BP by simply calculation, correlation from influence of dead carbon is necessary.
Iwatsuki, Teruki; Amano, Yuki; Murakami, Hiroaki; Nanjo, Isao; Aoki, Kazuhiro; Sasaki, Yoshito; Yoshikawa, Hideki
no journal, ,
This study aims to develop the evaluation methods of environmental changes and the recovery process around a large underground facility. To this end, hydrochemical changes in response to shaft excavation are analyzed based on the observation of water pressure, groundwater chemistry and microbial community structure around the URL. Regarding the chemical disturbance in the area, the redox potential (ORPSHE) of the groundwaters in the monitoring boreholes showed reducing condition (around -200 - -250 mV with pH of approx. 6-7) nevertheless the gallery is in oxidized condition. Theoretical calculation and chemical/microbial analysis of water sample suggests that the dominant redox buffering process around gallery is water-mineral-microbe interaction including iron-, sulphur-bearing materials (mineral and solutes).
Miyakawa, Kazuya; Amano, Yuki; Nanjo, Isao; Murakami, Hiroaki; Yabuuchi, Satoshi; Yokota, Hideharu; Iwatsuki, Teruki
no journal, ,
no abstracts in English
Miyakawa, Kazuya; Amano, Yuki; Murakami, Hiroaki; Iwatsuki, Teruki
no journal, ,
no abstracts in English