• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.3
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• pp.181-189
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• 2011

The smooth construction and operation of nuclear facilities requires understanding and support of both the local residents and the national people. It is essential that our country, which should maintain using nuclear energy for national energy security and economic growth, shall improve the social acceptance of nuclear energy. In order to identify the level of social acceptance of nuclear energy, this study investigated the perception of the local residents in Gyeongju and the public in other areas on a nuclear power plant and a low- and intermediate-level radioactive waste disposal facility through an individual interview. The subjects of the investigation were 450 persons. This study identified that perceptions of the respondents were somewhat dependent on the residential area, and derived the implications to be reflected in establishing the customized public-relation strategies.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.233-238
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• 2003

Several types of gamma-ray sensors were constructed by packing different numbers of fibers into aluminum tubes, and tested to detect the $^137Cs$ gamma ray. It has been found from this investigation that tapered fibers can be more efficient to collect the lights produced inside the sensor and transfer them into the transmitting fiber in order to predict the functioning of the tapered fiber, tapered plastic scintillators, composed of polystyrene with minute amount of dPOPOP and PPO or dPBD, were fabricated and tested for the detection of gamma rays from 1.0 1.5 3.0 5.0 ${\mu}Ci$ $^137Cs$ sources, and the pulse hight spectrum and the relationship between the radioactivity and the total counts are analyzed. It has been found from this study that the tapered scintillating optical fiber, if manufactured, can be practically applied to the development of gamma-ray sensors which can be deployed In ${\mu}Ci$-level radiation fields

• Tunnel and Underground Space
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• v.10 no.2
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• pp.237-248
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• 2000

Based on the preliminary results from the therm analysis, which is currently carrying, three-dimensional computer simulations using a finite element code, ABAQUS Ver. 5.8, were designed to determine the mechanically stable cavern and deposition hole spacing. Linear elastic modeling for the cases with different cavern and deposition hole spacing were carried out under three different in situ stress conditions. From the simulations, the response of the rock to the stress redistribution after the excavation of the openings could be investigated. Also the optimum cavern and deposition hole spacing could be estimated based on the factor of safety. When the in situ stress determined from the actual stress measurements in Korea were used, the case with cavern spacing of 40m and deposition hole spacing of 3m was in very stable condition, because the factor of safety was calculated as 3.42., When the in situ stress conditions for Sweden and Canada were used, the previous case, they seem to be in stable condition, since the factors of safety are still higher than 1.0. From these results, it was concluded that the rock will not fail even after the stress redistribution.

• Tunnel and Underground Space
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• v.13 no.4
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• pp.270-278
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• 2003

Transparency on the Total System Performance Assessment (TSPA) is the key issue to enhance the public acceptance for a permanent high level radioactive repository. Traditionally, the study on features, events and processes (FEPs) and associated scenarios has been regarded as the starting point to open the communicative discussion on TSPA such as what to evaluate, how to evaluate and how to translate outcomes into more friendly language that many stakeholders can easily understand and react with. However, in most cases, it has been limited to one way communication, because it is difficult for stakeholders outside the performance assessment field to assess the details on the story of the safety assessment, scenario and technical background of it. Fortunately, the advent of the internet era opens up the possibility of two way communication from the beginning of the performance assessment so that every stakeholder can exchange their keen opinions on the safety issues. To achieve it, KAERI develops the systematic approach from the FEPs to Assessment methods flow chart. All information is integrated into the web based program named FEAS (FEp to Assessment through Scenario development) under development in KAERI. In parallel, two independent systems are also under development the web based QA(Quality Assurance) system and the PA(Performance Assessment) input database. It is ideal to integrate the input data base with the QA system so that every data in the system can checked whenever necessary. Throughout the next phase R&D starting from the year 2003, these three systems will be consolidated into one unified system.

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.947-955
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• 2023

This study was conducted to investigate the awareness of spent nuclear fuel among residents in nuclear power plant areas and use it as basic data for establishing a disposal facility for high-level radioactive waste. 204 questionnaires collected online were analyzed using SPSS Window Ver 28.0. To verify differences between groups, t-test and one-way ANOVA were performed. And correlation analysis was conducted to confirm the relationship between variables. As a result, first, risk perception regarding nuclear-related accidents showed statistically significant differences depending on gender and educational level. The position on the construction of a permanent disposal facility for spent nuclear fuel showed a statistically significant difference depending on gender, education, and age, and the perception of the importance of each evaluation standard for establishing a spent nuclear fuel management plan showed a statistically significant difference depending on education and age. In terms of trust in information-providing institutions, trust in the National Assembly was found to be the lowest. Second, the results of the correlation analysis between variables showed that local residents are aware that an alternative to the current disposal of spent nuclear fuel is needed, and that financial support for the construction of a permanent disposal facility is needed. Therefore, in order to build a high-level radioactive waste disposal site, it is believed that it is necessary to increase trust in the government, collect opinions from local residents, and provide economic support.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.4
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• pp.281-291
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• 2013

A hypothetical repository was assumed to be located at the KURT (KAERI Underground Research Tunnel) site, and the travel times of radionuclides released from three source positions were calculated. The groundwater flow around the KURT site was simulated and the groundwater pathways from the hypothetical source positions to the shallow groundwater were identified. Of the pathways, three pathways were selected because they had highly water-conductive features. The transport travel times of the radionuclides were calculated by a TDRW (Time-Domain Random Walk) method. Diffusion and sorption mechanisms in a host rock matrix as well as advection-dispersion mechanisms under the KURT field condition were considered. To reflect the radioactive decay, four decay chains with the radionuclides included in the high-level radioactive wastes were selected. From the simulation results, the half-life and distribution coefficient in the rock matrix, as well as multiple pathways, had an influence on the mass flux of the radionuclides. For enhancing the reliability of safety assessment, this reveals that identifying the history of the radionuclides contained in the high-level wastes and investigating the sorption processes between the radionuclides and the rock matrix in the field condition are preferentially necessary.

• Tunnel and Underground Space
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• v.17 no.1 s.66
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• pp.17-25
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• 2007

Research and development for disposal of contaminants including radioactive wastes in deep underground have been carried out from laboratory works. However, validation and reliability of the data from the laboratory are arguing issues because they are not obtained from real disposal situations. Underground research laboratory (URL) is not only a solution to overcome such limitations, but also a valuable facility for performance assessment as an engineering scale. However, it requires much budget, and environmental issues can give rise to social conflicts easily. Such considering points related to URL are discussed as well as current status of worldwide URLs are introduced. Furthermore study plans for solute transport in a small-scale underground research tunnel (KURT), which was authorized recently as an non-radioactive facility in Korea, also described.

• Tunnel and Underground Space
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• v.25 no.6
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• pp.556-567
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• 2015

The evaluation of THM coupling behavior in deep underground repository condition is essential for the long term safety and stability assessment of high-level radioactive waste repository. In order to develop reliable THM analysis techniques effectively, an international cooperation project, DECOVALEX, is carried out. In DECOVALEX-2015 Task B2, the in situ THM experiment planned to be conducted by JAEA was modeled by the research teams from the participating countries. In this study, a THM coupling technique combining TOUGH2 and FLAC was developed and applied to 1 dimensional THM modeling, in which rock, buffer, and heater are considered. The results were compared with those from other research teams.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.06a
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• pp.35-36
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• 2009

지속가능 에너지원인 원자력은 또한 글로벌 에너지원의 특성을 갖추고 있다 핵연료는 원자로에 장전되는 신규 핵연료를 구성하고 있는 우라늄 채광 단계에서부터 연소 후에 발생하는 사용후 핵연료 (SNF 또는 SF) 관리 단계에 이르는 전과정에 걸쳐 핵연료 사이클로 파악되고 있다. 이러한 전과정 관점에서 볼 때, 핵연료 사이클에 관여하는 이해관계자는 자국뿐만 아니라 다국가 (multination)를 포함하고 있다. 특히, 후행 핵연료 사이클인 사용후 핵연료의 저장, 처리, 처분 단계에서는 다국가 시나리오를 배제하지 않는 사용후 핵연료 관리 전략의 도입이 고려될 수 있다. 여기서 다국가는 접경 국가, 인접 국가, 핵연료 공급 국가, 재처리 제공 국가, 재처리 위탁 국가, SNF 통과 허용 국가, SNF 저장 부지 제공 국가, SNF 향후 이용 국가 등이 될 수 있다 [김성호 2006]. 현재 우리나라에서는 여러 국가로부터 수입되고 있는 신규 핵연료 물질을 연소시켜 나온 사용후 핵연료를 부지내에 임시 저장하고 있다. 사용후 핵연료 발생량의 추산에 따르면, 2016년쯤에 현재 임시저장 용량이 포화될 예정이다 이러한 상황에서 다국가 시나리오를 포함한 관리 전략은 다국가 시나리오를 배제한 관리 전략과 다각적인 측면 에서 비교 검토될 필요성이 있다. 사용후 핵연료의 영구 처분장 부지 확보를 해결하기 위한 선행 단계로 공론화 단계가 지금 준비되고 있다. 예컨대, 단기 공론화 관리 방안의 하나로 비록 소극적인 입장이지만 타국 위탁 재처리 방식이 고려되고 있다 [KRS 2009] 이 연구에서는 단기적인 사용후 핵연료 관리 전략으로 여러 가지 다국가 수준의 저장, 처리, 처분 방식으로 바탕으로 다국가 시나리오들을 제안하려고 한다. 이들 다국가 시나리오를 포함한 관리 전략은 현재 다국가 시나리오를 배제한 국내 사용후 핵연료 처분장 부지 선정이 정치적/사회적 수용성 문제로 어려운 상황에 처할 경우에 해결책을 찾는 데에 기여하리라 본다. 또한, 부지 선정 단계에서 바라지 않는 난항이 나타나는 경우에 국가 차원의 한 대비책으로 다음을 제안한다: 한편으로는 자국 저장 시설이 추진되면서, 다른 편으로는 타국 저장 부지를 확보하는 전략이 검토되어야 한다. 이러한 이중 노선 (dual track) 전략은 여러 유럽 국가에서 이미 고려되고 있는 방안이다 [Greenpeace 2005] 다양한 다국성 정도 (a degree of multinationality) 의 저장, 처리, 처분 방식을 연결하는 가능한 다국가 시나리오 구조가 Fig.1에 제시되어 있다. 다국가 시나리오를 구성하는 기본 요소는 다음과 같다’ 1) 자국 임시 저장; 2) 자국 재처리; 3) 자국 중간 저장; 4) 자국 영구 처분; 5) 다국가 중간 저장; 6) 다국가 재처리; 7 ) 다국가 영구 처분. 이들 기본 요소들을 다국성 정도에 따라 결합하면 다양한 다국가 시나리오들이 얻어진다. 이들을 포함한 SNF 관리 전략은 크게는 1) 다국가 재처리 전략， 2) 다국가 저장 및 재처리 전략， 또는 3) 다국가 처분 전략 등으로 분류될 수 있다.

• Tunnel and Underground Space
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• v.31 no.5
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• pp.309-332
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• 2021

Natural barrier systems surrounding the geological repository for the high-level radioactive waste should guarantee the hydraulic performance for preventing or delaying the leakage of radionuclide. In the case of the behavior of a crystalline rock, the hydraulic performance tends to be decided by the existence of discontinuities, so the coupled hydro-mechanical(HM) processes on the discontinuities should be characterized. The discontinuum modelling can describe the complicated behavior of discontinuities including creation, propagation, deformation and slip, so it is appropriate to model the behavior of a crystalline rock. This paper investigated the coupled HM processes in discontinuum modelling such as UDEC, 3DEC, PFC, DDA, FRACOD and TOUGH-UDEC. Block-based discontinuum methods tend to describe the HM processes based on the fluid flow through the discontinuities, and some methods are combined with another numerical tool specialized in hydraulic analysis. Particle-based discontinuum modelling describes the overall HM processes based on the fluid flow among the particles. The discontinuum methods that are currently available have limitations: exclusive simulations for two-dimension, low hydraulic simulation efficiency, fracture-dominated fluid flow and simplified hydraulic analysis, so it could be improper to the modelling the geological repository. Based on the concepts of various discontinuum modelling compiled in this paper, the advanced numerical tools for describing the accurate coupled HM processes of the deep geological repository should be developed.