• 방사성폐기물학회지
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• 제19권1호
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• pp.113-121
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• 2021

A safety assessment of radioactive waste repositories is a mandatory requirement process because there are possible radiological hazards owing to radionuclide migration from radioactive waste to the biosphere. For a reliable safety assessment, it is important to establish a parameter database that reflects the site-specific characteristics of the disposal facility and repository site. From this perspective, solubility, a major geochemical parameter, has been chosen as an important parameter for modeling the migration behavior of radionuclides. The solubilities were derived for Am, Ni, Tc, and U, which were major radionuclides in this study, and on-site groundwater data reflecting the operational conditions of the Gyeongju low and intermediate level radioactive waste (LILW) repository were applied to reflect the site-specific characteristics. The radiation dose was derived by applying the solubility and radionuclide inventory data to the RESRAD-OFFSITE code, and sensitivity analysis of the dose according to the solubility variation was performed. As a result, owing to the low amount of radionuclide inventory, the dose variation was insignificant. The derived solubility can be used as the main input data for the safety assessment of the Gyeongju LILW repository in the future.

• 방사성폐기물학회지
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• 제17권4호
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• pp.447-457
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• 2019

일본에서는 2000년 고준위방사성폐기물의 심층처분을 위한 「특정방사성폐기물의 최종 처분에 관한 법률」을 제정하고 부지선정을 착수하였으나, 부지선정 절차에 참여를 원하는 지자체가 존재하지 않았다. 따라서, 일본 정부는 2015년 문헌조사 단계에 새로운 부지선정을 절차를 개발하고, 지자체의 공모를 촉진하고자 2017년 6월 28일 심층처분을 위한 전국규모 과학적 특성 지도를 발간하였다. 이 지도는 심층처분장 초기 혹은 개념단계에 고려되는 요건 및 기준 등을 제공하고 심층처분을 위한 적합성을 분석함으로써, 공공의 이해도 증진과 지자체와의 의견교환 등을 위해서 유용하게 활용되고 있다.

• 방사성폐기물학회지
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• 제18권spc호
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• pp.75-87
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• 2020

The Korea Atomic Energy Research Institute (KAERI) has developed geological repository systems for the disposal of high-level wastes and spent nuclear fuels (SNFs) in South Korea. The purpose of the most recently developed system, the improved KAERI Reference Disposal System Plus (KRS⁺), is to dispose of all SNFs in Korea with improved disposal area efficiency. In this paper, a system-level safety assessment model for the KRS⁺ is presented with long-term assessment results. A system-level model is used to evaluate the overall performance of the disposal system rather than simulating a single component. Because a repository site in Korea has yet to be selected, a conceptual model is used to describe the proposed disposal system. Some uncertain parameters are incorporated into the model for the future site selection process. These parameters include options for a fractured pathway in a geosphere, parameters for radionuclide migration, and repository design dimensions. Two types of SNF, PULS7 from a pressurized water reactor and Canada Deuterium Uranium from a heavy water reactor, were selected as a reference inventory considering the future cumulative stock of SNFs in Korea. The highest peak radiological dose to a representative public was estimated to be 8.19×10^-4 mSv·yr^-1, primarily from ¹²⁹I. The proposed KRS⁺ design is expected to have a high safety margin that is on the order of two times lower than the dose limit criterion of 0.1 mSv·yr^-1.

• 방사성폐기물학회지
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• 제18권1호
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• pp.91-102
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• 2020

국내 3단계 매립형 처분시설은 2018년도 한국원자력환경공단의 중·저준위 방폐물관리시행계획에 의하면 주로 원전 해체 현장에서 발생하는 극저준위방폐물을 수용하기 위해 2019년 4월부터 2026년 2월까지 총 104,000드럼(2개 트렌치)을 수용하기 위해 건설이 계획 중이다(총 2,246억원 투입). 이후 총 5개 트렌치에 260,000드럼이 총 34,076 ㎡의 면적에 단계적으로 수용되며 따라서 현재 한국원자력환경공단은 관련 인수기준을 마련 중에 있다. 극저준위방폐물 처분시설 인수기준의 경우 프랑스, 스페인 등이 전용 처분시설을 운영하면서 자국의 인수기준을 합리적으로 잘 준용하고 있으나 본 논문에서는 해체방폐물의 처분에 가장 경험이 많은 미국의 처분시설을 고려하여 국내 매립형 처분시설에 우선적으로 반영되어야 할 사항이 있는지 분석하였고 이를 통하여 경주내 3단계 매립형 처분시설의 인수기준 마련에 도움이 되고자 하였다.

• Nuclear Engineering and Technology
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• 제33권2호
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• pp.156-165
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• 2001

A radiological safety assessment was performed for a hypothetical near-surface radioactive waste repository as a simple screening calculation to identify important nuclides and to provide insights on the data needs for a successful demonstration of compliance. Individual effective doses were calculated for a conservative ground water pathway scenario considering well drilling near the site boundary. Sensitivity of resulting ingestion dose to input parameter values was also analyzed using Monte Carlo sampling. Considering peak dose rate and assessment time scale, C-14 and T-129 were identified as important nuclides and U-235 and U-238 as potentially important nuclides. For C-14, the dose was most sensitive to Darcy velocity in aquifer The distribution coefficient showed high degree of sensitivity for I-129 release.

• 방사성폐기물학회지
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• 제18권spc호
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• pp.51-62
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• 2020

In this paper, an approach developed by the Finnish nuclear waste management organization, Posiva, for the construction license of a geological repository was reviewed. Furthermore, a computer program based on the approach was developed. By using the computer program, the lifetime of a copper disposal canister, which was a key engineered barrier of the geological repository, was predicted under the KAERI Underground Research Tunnel (KURT) geologic conditions. The computer program was developed considering the mass transport of corroding agents, such as oxygen and sulfide, through the buffer and backfill. Shortly after the closure of the repository, the corrosion depths of a copper canister due to oxygen in the pores of the buffer and backfill were calculated. Additionally, the long-term corrosion of a copper canister due to sulfide was analyzed in two cases: intact buffer and eroded buffer. Under various conditions of the engineered barrier, the corrosion lifetimes of the copper canister due to sulfide significantly exceeded one million years. Finally, this study shows that it is necessary to carefully characterize the transmissivity of rock and sulfide concentration during site characterization to accurately predict the canister lifetime.

• 지질공학
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• 제33권2호
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• pp.335-353
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• 2023

본 논문은 고준위방사성폐기물 처분시설 부지선정 과정의 해외사례를 알아보고, 각 나라별 부지선정 과정 각 단계에서 고려되는 항목을 알아보는 데 중점을 두었다. 부지선정 과정은 지역 주민들의 의견이 반영되는 시기와 각 나라별 지질학적 상황에 따라 선별기준이 서로 다르다. 처분 선도국의 경우 부지를 선정하는 방식을 크게 세 가지로 나누어 볼 수 있는데, 첫 번째는 정부 주도의 부지선정 후 주민동의를 통해 부지를 선정하는 방식이고, 두 번째는 기존 조사자료를 바탕으로 배제지역을 제외한 후 지역사회와의 지속적인 소통을 통해 부지를 선정하는 방식이고, 세 번째는 자발적 참여 의사를 밝힌 지역사회를 대상으로 부지선정을 하는 방식이다. 첫 번째 방식에 해당하는 미국의 경우 총 6단계의 부지선정 단계를 통해 네바다주의 Yucca Mountain을 최종 처분부지로 선정하였으나 주지사와 환경단체의 반대로 중단된 상태이다. 두 번째 방식에 해당하는 스웨덴, 스위스, 독일의 경우 총 3단계의 부지선정 단계를 통해 부지를 선정한다. 스웨덴과 스위스는 부지선정을 완료했으며 독일은 현재 3단계 중 1단계의 Step 2를 진행 중이다. 세 번째 방식에 해당하는 영국의 경우 총 6단계의 부지선정 단계를 계획하여 선정 과정을 진행하다가 지역사회의 참여저조로 중단되었으며, 그 이후 지역사회와 협력하기 위한 프로세스를 추진 중이다. 우리나라의 경우에는 2030년부터 원전 내 사용후핵연료 임시 저장시설이 포화 되기 시작하므로 부지선정 추진이 필요하다. 법과 제도를 확정하는 것을 우선으로 하여, 부지선정을 추진하고 이 과정에서 투명한 절차로 과학적 근거에 기반하여 지역사회와의 지속적인 소통을 통해 부지선정을 추진해 나가야 할 것이다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2009년도 학술논문요약집
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• pp.179-181
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• 2009

This presentation is a short summary of the Finnish process for selection and characterisation of potential sites for geological deep disposal of spent nuclear fuel. The process lasted nearly two decades from 1983 to 2000, and was concluded by the Government's Decision in Principle (DiP) on the construction of a repository in Olkiluoto. This presentation gives an outline of the early site selection criteria and a description of this process.

• Nuclear Engineering and Technology
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• 제53권2호
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• pp.549-561
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• 2021

Indonesia has policies and strategies for the management of radioactive waste and spent nuclear fuel that arises from the use of nuclear research and development facilities, including three research reactors, and the use of radioisotopes in medicine and industries. The Indonesian government has provided extensive facilities such as an independent regulatory organization (BAPETEN) and a centralized radioactive waste management organization (CRWT-BATAN). Further, the presence of regulations and several international conventions guarantee the protection of the public from all risks due to handling radioactive waste and spent nuclear fuel. However, the sustainability of radioactive waste management in the future faces various challenges, such as disposal issues related to not only to site selection but also financing of radioactive waste management. Likewise, the problem of transportation persists; as an archipelago country, Indonesia still struggles to manage the infrastructure required for the transport of radioactive materials. The waste from the production of the radioisotopes, especially from the production of 99Mo, requires special attention because BATAN has never handled it. Indonesia should also resolve the management of NORM from various activities. In Indonesia, the definition of radioactive waste does not include NORM. Therefore, the management of this waste needs revision and improvement on the regulations, infrastructure, and technology.

• Nuclear Engineering and Technology
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• 제42권1호
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• pp.17-36
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• 2010

In this study, we compare the mass release rates of radionuclides(1) from waste forms arising from the KIEP-21 pyroprocessing system with (2) those from the directly-disposed pressurized-water reactor spent fuel, to investigate the potential radiological and environmental impacts. In both cases, most actinides and their daughters have been observed to remain in the vicinity of waste packages as precipitates because of their low solubility. The effects of the waste-form alteration rate on the release of radionuclides from the engineered-barrier boundary have been found to be significant, especially for congruently released radionuclides. the total mass release rate of radionuclides from direct disposal concept is similar to those from the pyroprocessing disposal concept. While the mass release rates for most radionuclides would decrease to negligible levels due to radioactive decay while in the engineered barriers and the surrounding host rock in both cases even without assuming any dilution or dispersal mechanisms during their transport, significant mass release rates for three fission-product radionuclides, $^{129}I$, $^{79}Se$, and $^{36}Cl$, are observed at the 1,000-m location in the host rock. For these three radionuclides, we need to account for dilution/dispersal in the geosphere and the biosphere to confirm finally that the repository would achieve sufficient level of radiological safety. This can be done only after we have known where the repository site would by sited. the footprint of repository for the KIEP-21 system is about one tenth of those for the direct disposal.