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demonstration facility in Horonobe, Hokkaido, Japan. Abstracts 6) 40268 – Design Options for HLW Repository Operation Technology, (III) Transportation and Horizontal Emplacement of Pre-Fabricated EBS Module (PEM) Susumu Kawakami, IHI Corporation (Japan); Hitoshi Nakashima, Hidekazu Asano, RWMC (Japan) As one of the repository operation technologies for high-level radioactive waste?(HLW), the pre-fabricated engineered barrier system (EBS) module (PEM) was carried out the examination of handling and emplacement technique for EBS. <strong>The</strong> PEM technology was examined to confirm technological applicability. <strong>The</strong> PEM is concept of the integration of EBS as the module in the surface facilities, and transporting the module underground facilities. This concept is the one of the candidate concepts of horizontal emplacement techniques for EBS in Japan. <strong>The</strong>refore, PEM is the same level large size and heavy weight as EBS, and it is necessary to examine the applicability of handling and emplacement techniques. Full-scale level tests were performed to confirm the applicability of these techniques with the air bearing/air jack devices. In the tests, we prepared the testing devices of full-scale level size/weight and confirmed the applicability of these technologies as an elemental technology on the condition of considering the environment of an underground tunnel. <strong>The</strong> air bearing test that produced the surface-roughness of the tunnel environment was carried out the evaluation concerning the transportation performance of the air bearing. And, the air jack test was carried out the holding and emplacement of PEM. <strong>The</strong> repository operation technology with the air bearing/jack device was confirmed to execute the examination, and to apply to handling and emplacement technique for PEM. 7) 40236 – Design Options for HLW Repository Operation Technology, (IV) Shotclay Technique for Seamless Construction of EBS Ichizo Kobayashi, Soh Fujisawa, Makoto Nakajima, Masaru Toida, Kajima Corporation (Japan); Hitoshi Nakashima, Hidekazu Asano, RWMC (Japan) In Japan, the construction method of the buffer material has been investigated focusing on the block emplacement and in-situ compaction methods. Under the current concept of geological disposal of radioactive waste, since it has been important that the barrier satisfies the dry density requirement as a mass, no enough attention has been paid to the distribution of density and the gaps between blocks which were caused by the conventional methods. This is based on the assumption that bentonite swells from the permeation of groundwater and that the density eventually becomes homogeneous. However, it is not clear whether the high density bentonite does in fact swell until the density is homogeneous. <strong>The</strong> effects of density distribution and the gaps in long-term high impermeability of a bentonite-engineered barrier may be not small. <strong>The</strong>refore, the option of the construction method for a bentonite-engineered barrier that does not have such uncertainty concerning the implementation of a disposal concept should be prepared. In order to remove such uncertainty, the high-density spray method for bentonite, termed the shotclay method, was developed as a method for constructing a uniform bentonite-engineered barrier without gaps even in a narrow space. <strong>The</strong> shotclay method is used to construct compacted soil at high density by spraying material preconditioned with water. Using this method, the dry density of 1.6 Mg /m3, which was considered impossible with the spraying method, is achieved. In this study, the applicability of the shotclay method to HLW bentonite-engineered barriers was confirmed experimentally. In the tests, an actual scale vertical-type HLW bentonite engineered barrier was constructed. This was a bentonite-engineered barrier with a diameter of 2.22 m and a height of 3.13 m. <strong>The</strong> material used was bentonite with 30% silica sand, and water content was adjusted by mixing chilled bentonite with powdered ice before thawing. Work progress was 11.2 m3 and the weight was 21.7 Mg. <strong>The</strong> dry density of the entire buffer was 1.62 Mg/m3, and construction time was approximately 8 hours per unit. After the formworks were removed, the core and block of the actual scale HLW bentonite-engineered barrier were sampled to confirm homogeneity. As a result, homogeneity was confirmed, and no gaps were observed between the formwork and the buffer material and between the simulated waste and the buffer material. <strong>The</strong> applicability to HLW of the shotclay method has been confirmed through this examination. 8) 40254 – Design Options for HLW Repository Operation Technology, (V) Preliminary Study and Small Scale Experiments on the Method of Removal of Buffer Material with Salt Solution Satohito Toguri, Jiho Jang, Takashi Ishii, Mitsunobu Okihara, Kengo Iwasa, SHIMIZU CORPORATION (Japan); Hitoshi Nakashima, Hidekazu Asano, RWMC (Japan) During the construction of geological disposal facilities for high-level radioactive waste, it may be decided to free and retrieve the emplaced overpack for some reasons. Thus we have been paying attention to a method of slurrying bentonite buffer around the overpack with fluid (salt solution) for freeing it. A few laboratory tests were performed to research the feasibility and verify the applicability of the method. <strong>The</strong> test piece of the buffer material consists of 70wt% bentonite and 30wt% sand, and its dry density is 1.6 g/mL, and the volume of the cylindrical test piece is 100mL. First, the time was measured for test pieces to be dissolved in various strength NaCl solutions. In case of 47% saturated test pieces, they could be easily dissolved in NaCl 3 or 4wt% solution, and the dissolved material was deposited soon in the slurry. Second, the results from the flushing experiments applied to a small specimen of buffer material suggest that flushing 4wt% NaCl solution is effective for speedy stripping of buffer material. Third, the times were measured for 90
Abstracts various percentage saturated test pieces to be dissolved in 4wt% NaCl solution. <strong>The</strong> time for 47% saturated one was shorter than 1 Hr, but the time for 67% was longer than 5 Hrs. In case of 88%, it had not been dissolved yet in 7Hrs, but after drying the test piece it could be easily dissolved in 5 minutes. <strong>The</strong> results from the laboratory tests indicate that the unsaturated buffer material can be easily dissolved in NaCl 4wt% solution, and the wet buffer material can be dissolved by immersing in NaCl 4wt% solution after process of dry-hot-air blowing. Finally, in order to confirm the effect of removal processes, simulated experiments were executed using small scale (1/14 scale) specimens. <strong>The</strong> 47% saturated buffer material specimen was easily removed by the process of immersing in NaCl solution, flushing NaCl solution, removing slurry by vacuum device, and re-using NaCl solution after deposition. In the nearly saturated case, it was removed in cyclic process of dry-hot-air blowing and immersing in NaCl 4wt% solution. SESSION H10: Site Characterization and Modeling of Geological Environment (2) 1) 40135 – Dry-run of Site Investigation Planning using the Manual for Preliminary Investigation in Japan Shigeki Akamura, Tadashi Miwa, NUMO (Japan); Tatsuya Tanaka, Obayashi Corporation (Japan); Hiroshi Shiratsuchi, Tokyo Electric Power Service Co.,Ltd. (Japan); Atsushi Horio, DIA CONSULTANTS CO., Ltd. (Japan) A stepwise site selection process has been adopted for geological disposal of HLW in Japan. Literature surveys, followed by preliminary investigations (PI) and, finally, detailed investigations in underground facilities will be carried out in the successive selection stages. In the PI stage, surface-based investigations such as borehole surveys and geophysical prospecting will be implemented. NUMO recognizes that sustained improvement of internal expertise is very important to ensure that the PI will be implemented rigorously and efficiently. <strong>The</strong>refore existing knowledge and experience in the planning and management of site investigations were compiled in the form of two manuals: the Preliminary Investigation Planning Manual (PIPM) and the Preliminary Investigation Management Manual (PIMM). <strong>The</strong> manuals were based on the experience in overseas site investigation programs, and has further been refined by taking experience from site investigations in Japan (e.g. from generic URLs) into account. NUMO has applied them in its own R&D programs, such as the dry-run studies for various geological environments (e.g. coastal and island). This paper outlines the process and the results of a dry-run study which applied the revised PIPM to the Yokosuka area where the demonstration and validation project for PI technologies has been conducted. <strong>The</strong> planning of the PI was performed according to the eight steps in the PIPM. <strong>The</strong> GET (Geosphere Evaluation Team) consisting of staffs from site characterization, performance assessment and repository design groups in NUMO, was established for the PI planning. This task force team has responsibility not only for the planning but also for making key decisions regarding the performance of the program. <strong>The</strong> SDMT (Site Descriptive Modeling Team) was formed for site modeling activities. Initial geoscientific conceptual models were established based on the interpretation of existing site information around the area. Various conceptual models were constructed due to the limited amount of existing information. Site descriptive models were derived taking such variations in the conceptual models into account. <strong>The</strong> main targets for the PI planning were specified considering the uncertainties in the models, requests from the repository concept as well as legal requirement. <strong>The</strong> integrated PI program set out the sequence of investigations and characterization activities to achieve the main targets. Lessons learned in the PI planning and the applicability of the revised PIPM were addressed as the conclusion of the dry-run. 2) 40070 – Evaluation of the long-term evolution of the groundwater system in the Mizunami area, Japan Takashi Mizuno, Teruki Iwatsuki, JAEA (Japan); Antoni E. Milodowski, British Geological Survey (UK) This study aimed to develop a methodology for assessing the evolution of the long-term groundwater system, using fracture-filling calcite. Fracture-filling calcite mineralization, closely associated with groundwater flow paths, in deep (to ca. 1000 m) granitic rocks in and around Mizunami area, Japan, was studied by optical and cathode-luminescence microscopy, SEM, laser ablation microprobe-ICP MS, stable isotope geochemistry, and fluid inclusion analysis. As the results, four generations (I to IV) of calcite precipitation can be differentiated based on their morphological and isotopic characteristics. Calcite I - calcite with indistinct morphology including the wall rock fragments (d13CPDB -31.4 ‰ ~ -7.5 ‰, d18OPDB -32.7 ‰ ~ -8.0 ‰); Calcite II -calcite with euhedral rhombohedral and hexagonal crystal forms (d13CPDB 22.5 ‰ ~ -1.8 ‰, d18OPDB -15.5 ‰ ~ -6.5 ‰); Calcite III - calcite forming c-axis elongated rhombohedral overgrowths seeded on top of Calcite II (d13CPDB -18.0 ‰ ~ 5.8 ‰, d18OPDB -11.1 ‰ ~ -2.3 ‰); Calcite IV - calcite forming small rhombohedral crystals nucleated on the surface of Calcite III (d13CPDB -12.5 ‰ ~ -1.7 ‰, d18OPDB -12.7 ‰~7.8 ‰). Carbon and oxygen isotopic ratios suggests that the Calcite I is of hydrothermal origin. On the other hand, Calcite II, IV and III were precipitated from freshwater and marine water, respectively. From the geohistorical point of view, depositional setting in Mizunami area was changed during Tertiary and Quaternary. Mizunami Group overlying above Toki granite is changed from lacustrine strata to marine strata. In addition, upper Seto Group is a lacustrine stratum. <strong>The</strong> change of depositional setting corresponds to groundwater system assumed by mineralogical study. As there is no other evidence linked to penetration of high-salinity water into deep environment in this area, it is 91
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FINAL PROGRAM The
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General Information Objectives and
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Insurance and Liability All partici
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Map around Conference</stro
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ICEM2010 Technical Sessions at a Gl
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ICEM2010 Technical Sessions at a Gl
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Sphiee Robert, Benoit Carpentier, S
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4. 40007 - Chemical Decontamination
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3. 40060 - The Dep
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concept for disposal of HLW Lou Are
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Materials Corp. (Japan) 7. 40047 -
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List of Exhibitors The</str
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Abstracts OPENING SESSION “Nuclea
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Page 43 and 44: Abstracts environmental hazard. <st
Page 45 and 46: Abstracts US-Russian Global Threat
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Page 51 and 52: Abstracts stability, set times, hea
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Page 57 and 58: Abstracts dewatered resin waste tog
Page 59 and 60: Abstracts widely used portable assa
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Page 63 and 64: Abstracts Onsite activities took pl
Page 65 and 66: Abstracts operating plant through d
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Page 89 and 90: Abstracts SESSION L7: Storage and D
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Page 119 and 120: Abstracts SESSION M3: EM/PI Poster
Page 121 and 122: Sohei IKEGAMI Japan Atomic Energy A
Page 123 and 124: Jin-Seop KIM Korea Atomic Energy Re
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