• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.4
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• pp.243-251
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• 2015

Nuclear power is currently the second largest power supply method in Korea and the number of nuclear power plants are planned to be increased as well. However, clear management policy for spent fuels generated from nuclear power plants has not yet been established. The back-end fuel cycle, associated with nuclear material flow after nuclear reactors is a collection of technologies designed for the spent fuel management and the spent fuel management policy is closely related with the selection of a nuclear fuel cycle. Cost is an important consideration in selection of a nuclear fuel cycle and should be determined by adding external cost to private cost. Unlike the private cost, which is a direct cost, studies on the external cost are focused on nuclear reactors and not at the nuclear fuel cycle. In this research, external cost indicators applicable to nuclear fuel cycle were derived and quantified. OT (once through), DUPIC (Direct Use of PWR SF in CANDU), PWR-MOX (PWR PUREX reprocessing), and Pyro-SFR (SFR recycling with pyroprocessing) were selected as nuclear fuel cycles which could be considered for estimating external cost in Korea. Energy supply security cost, accident risk cost, and acceptance cost were defined as external cost according to precedent and estimated after analyzing approaches which have been adopted for estimating external costs on nuclear power generation.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.2
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• pp.155-162
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• 2008

Inventories to be disposed of, reference turnup, and source terms for CANDU spent fuel were evaluated for geological disposal system design. The historical and projected inventory by 2040 is expected to be 14,600 MtU under the condition of 30-year lifetime for unit 1 and 40-year lifetime for other units in Wolsong site. As a result of statistical analysis for discharge burnup of the spent fuels generated by 2007, average and stand deviation revealed 6,987 MWD/MtU and 1,167, respectively. From this result, the reference burnup was determined as 8,100 MWD/MtU which covers 84% of spent fuels in total. Source terms such as nuclide concentration for a long-term safety analysis, decay heat, thermo-mechanical analysis, and radiation intenity and spectrum was characterized by using ORIGEN-ARP containing conservativeness in the aspect of decay heat up to several thousand years. The results from this study will be useful for the design of storage and disposal facilities.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.465-468
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• 2003

It has taken a growing interest about environmental problems such as global warming and water pollution. Because of intensified environmental problems, it would be going on the research about environmental preservation and harmful factor reduction. Also, it makes ISO to show the quantitative data about LCA analysis. The research of LCA method in the domestic construction industry has advanced stealing from a national point of view. In this study, it would be possible to confirm the feasibility of a plan by LCA analysis. Moreover, the result of life cycle cost which deliberate the influence cost of environment in the steps of material production, construction, maintenance, and disposal has made to be 74,819,560,776 won in a plan and 78,979.469,602won in alternative. That is, it would analysis for a plan to reduce 4,159,908,826 won for alternative.

• Nuclear industry
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• v.4 no.6 s.22
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• pp.19-23
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• 1984

현재 우리나라에는 3기의 원전이 운전중에 있으며 6기가 건설중에 있다. 즉, 2기의 가압경수로(PWR)의 1기의 가압중수로(HWR)가 운전중에 있으며 건설중인 것은 모두 PWR이다. 현재 추진되고 있는 원전계획을 수행하면, 1990년에는 사용후핵연료가 년간 약200톤씩 방출될 것이며, 2000년에는 500톤 정도가 방출되게 된다. 이와 같은 핵사용후연료는 현재 소내저장하고 있으나 '90년대 중반 부터는 소내저장용량이 한계에 달하게 될 것으로 전망되고 있다. 따라서 본교에서의 이와 같은 소내저장 한계성에 대처할 수 있는 가능한 방안을 검토하고, 이를 경제성 측면에서 분석하고자 하였다. 사용후핵연료의 관리방안에 대한 경제성 분석을 위해서는 장래의 원전계획, 원자로형 및 핵연료주기방식 등에 대한 여러 가지 가정이 필요하게 된다. 원전계획은 정부에서 발표한 $\ulcorner$5차5개년 수정계획$\lrcorner$에 의거하여 원전시설용량은 현재의 2GWe에서 2000년에는 22GWe로, 2025년에는 44GWe로 늘어나는 것으로 보았다. 이와 같은 원전계획을 바탕으로 6가지 핵연료주기에 관한 시나리오를 설정하였다. 즉, 사용후핵연료를 비순환방식으로 운영하는 2가지 경우, 순환방식으로 운영되는 3가지 경우 그리고 FBR에 활용하는 1가지의 경우에 대하여 검토하였다. 사용후핵연료의 관리방식에 따른 장기적인 안목에서의 경제성 분석은 핵연료주기비용 뿐만아니라 원전의 투자비도 함께 분석하는 것이 합리적이며, 따라서 본교에서는 계획기간 동안의 6가지 시나리로에 따른 원전 및 핵연료주기에 관한 총 투자비를 비교하였고, 1982년 가격으로 현가화한 단가도 비교${\cdot}$검토 하였다. 이와 같은 6가지 시나리오에 대한 경제성을 비교해 본 결과, 핵연료주기선택의 경제성평가에 큰 영향을 주는 핵연료주기요소는 재처리비, 재처리시 방출되는 폐기물의 처리${\cdot}$처분비 그리고 사용후핵연료 저장방식으로 판명되었으며 6가지 시나리오에 대한 경제성 비교평가 결과, 다음과 같은 결론을 얻었다. 단기적인 안목에서는 소내저장용량을 확장하는 방안이 가장 바람직하며, 중기적인 관점에서는 소외집중저장설비가 활발히 수행되는 시점에서는 사용후핵연료를 재처리하여 재활용하는 방안도 강구되어야 할 것이다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.2
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• pp.163-169
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• 2015

In many nuclear power plant sites in Korea, high density storage racks were installed in the spent fuel pool to expand the spent fuel storage capacity. Nevertheless, the capability of the Hanbit nuclear site will be saturated by 2024. Also, 10 NPPs will reach their design life expiration date by 2029. In the case of the US, SFPI (Spent Fuel Pool Island) operated temporarily as a spent fuel storage option before spent nuclear fuels were transported to an interim storage facility or a final disposal facility. As a spent fuel storage option after shutdown during decommissioning, the SFPI concept can be expected to have the following effects: reduced occupational exposure, lower cost of operation, strengthened safety, and so on. This paper presents a case study associated with the regulations, operating experiences, and systems of SFPI in the US. In conclusion, the following steps are recommended for applying SFPI during decommissioning in Korea: confirmation of design change scope of SFPI and expected final cost, the submission of a decommissioning plan which is reflected in SFPI improvement plans, safety assessment using PSR, application of an operating license change for design change, regulatory body review and approval, design change, inspection by the regulatory body, education and commissioning for SFPI, SFPI operation and periodic inspection, and dismantling of SFPI.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.1
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• pp.21-34
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• 2015

Source term analysis should be carried out to prepare the decommissioning of the nuclear power plant. In the planning phase of decommissioning, the classification of decommissioning wastes and the cost evaluation are performed based on the results of source term analysis. In this study, the verification of MCNP/ORIGEN-2 model is carried out for preliminary source term calculation for Wolsung Unit 1. The inventories of actinide nuclides and fission products in fuel bundles with different burn-up were obtained by the depletion calculation of MCNPX code modelling the single channel. Two factors affecting the accuracy of source terms were investigated. First, the neutron spectrum effect on neutron induced activation calculation was reflected in one-group microscopic cross-sections of relevant radio-isotopes using the results of MCNP simulation, and the activation source terms calculated by ORIGEN-2 using the neutron spectrum corrected library were compared with the results of the original ORIGEN-2 library (CANDUNAU.LIB) in ORIGEN-2 code package. Second, operation history effect on activation calculation was also investigated. The source terms on both pressure tubes and calandria tubes replaced in 2010 and calandria tank were evaluated using MCNP/ORIGEN-2 with the neutron spectrum corrected library if the decommissioning wastes can be classified as a low level waste.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2
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• pp.217-225
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• 2020

Concrete waste accounts for approximately 70~80% of the total waste generated during the decommissioning of nuclear power plants (NPPs). Based upon the concentration of each radionuclide, the concrete waste from the decommissioning can be used in the determination of the clearance threshold used to classify waste as radioactive. To reduce the cost of radioactive concrete waste disposal, it is important to perform decontamination before self-disposal or limited recycling. Therefore, it is necessary to estimate the internal radioactivity distribution of radioactive concrete waste to ensure effective decontamination. In this study, the performance metrics of various Compton reconstruction algorithms were compared in order to identify the best strategy to estimate the internal radioactivity distribution in concrete waste during the decommissioning of NPPs. Four reconstruction algorithms, namely, simple back-projection, filtered back-projection, maximum likelihood expectation maximization (MLEM), and energy-deconvolution MLEM (E-MLEM) were used as Compton reconstruction algorithms. Subsequently, the results obtained by using these various reconstruction algorithms were compared with one another and evaluated, using quantitative evaluation methods. The MLEM and E-MLEM reconstruction algorithms exhibited the best performance in maintaining a high image resolution and signal-to-noise ratio (SNR), respectively. The results of this study demonstrate the feasibility of using Compton images in the estimation of the internal radioactive distribution of concrete during the decommissioning of NPPs.

• Journal of Soil and Groundwater Environment
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• v.8 no.3
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• pp.37-44
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• 2003

Fuel oxygenates, such as Methyl tertiary Butyl Ether (MTBE) is additive in gasoline used to reduce air pollution. Gasoline components and fuel additives can leak: form underground storage tanks. MTBE is far more water soluble than gasoline hydrocarbons like BTEX then it travels at essentially the same velocity as groundwater. MTBE in drinking water causes taste and odor problems. Therefore, the purpose of the this study is to examine the ability of ground tire to sorb MTBE in water. The study consisted of running both batch and column tests to determine the sorption capacity, the required sorption equilibration time, and the flow through utilization efficiency of ground tire. The batch test result indicated that ground tire can attain equilibrium sorption capacities about 0.5 mg of MTBE. The result of column test indicate that ground tire has on the 36% utilization rate. Finally, it is clear that ground tire represented an attractive and relatively inexpensive sorption medium for a MTBE. Authors thought that to determine the economic costs of ground tire utilization, the cost to sorb a given mass of contaminant by ground tire will have to be compared to currently accepted sorption media. The cost comparison will also have to include regeneration and disposal cost.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.1
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• pp.59-73
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• 2019

A decontamination technology for radioactive liquid wastes was newly developed and hypothetically applied to the liquid waste management system (LWMS) of the nuclear power plant (NPP) to evaluate its decontamination efficacy for the purpose of the fundamental reduction of spent resins. The basic principle of the developed technology is to convert major radionuclide ions in the liquid wastes into inorganic crystal minerals via chemical or biological techniques. In a laboratory batch experiment, the biological method selectively removed more than 80% of cesium within 24 hours, and the chemical method removed more than 95% of cesium. Other major nuclides (Co, Ni, Fe, Cr, Mn, Eu), which are commonly present in nuclear radioactive liquid wastes, were effectively scavenged by more than 99%. We have designed a module including the new technology that could be hypothetically installed between the reverse osmosis (R/O) package and the organic ion-exchange resin in the LWMS of the APR1400 reactor. From a technical evaluation for the virtual installation, we found that more than 90% of major radionuclides in the radioactive liquid wastes were selectively removed, resulting in a large volume reduction of spent resins. This means that if the new technology is commercialized in the future, it could possibly provide drastic cost reduction and significant extension of the life of resins in the management of spent resins, consequently leading to delay the saturation time of the Wolsong repository.

• Management & Information Systems Review
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• v.38 no.4
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• pp.61-78
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• 2019

When calculating gains from transfers of assets inherited or donated, the value recognized at the market price as of the date of inheritance or acquisition is recognized as the actual transaction value at the time of acquisition. However, Precedents for the appeal for review by the NTS, the request for adjudgment by the Tax Tribunal(TT) and the request of examination by the Board of Audit and Inspection of Korea(BAI) and the cases of the lawsuit have not shown a consistent results on how much such a the actual transaction value will be measured. This study investigates the operating state of the current tax appeal system using the statistical data of the TT, NTS, and BAI and cases of the lawsuit from 2008 to 2017, and suggests the Improvement of Capital Gains Tax Act on the transfer of inherited and donated property. As a result, total number of requested cases has diminished because cases of the pre-assessment review and the reconsideration appeal by the NTS have decreased steadily over the past decade, while the cases of the lawsuit and the administrative trials(the request for adjudgment by the TT, the appeal for review by the NTS, and the request of examination by the BAI) have been steadily increasing. Also This study found that more than 40% of the complainants proceeded with the cases of the lawsuit proceedings in disagreement with the disposition of tax dissatisfaction under the administrative trials. In addition, Even though the retrospective appraisal price is not recognized as the market price due to the strict interpretation of the tax regulations, it can be seen that it is interpreted as a more expanded concept in the application of the market price than the government office or the tax judge. Therefore, according to the precedents of the cases lawsuit, it is necessary to establish a regulation on the recognition of retroactive appraisal value.