• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.256-260
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• 2003

The paper is aiming at presenting the proper treatment method and procedures of ILW waste to both waste generators and acceptor so that the waste characteristics are satisfied with the WAC(Waste Acceptance Criteria) and as a result, the disposal facility would be operating safely. The ILW generators are responsible for reducing the volume of waste, treating and packaging the waste in order to meet the WAC, and acceptor has an obligation of inspecting the waste in conformity with the acceptance procedure established by regulation. Recently, a number of countries including France and USA examine the disposal acceptability of ILW waste by the WCP(Waste Package Quality Certification Program).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.265-279
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• 2017

The Gyeongju underground silo type disposal facility, approved for use in December 2014, is in operation for the disposal of low and very low-level radioactive wastes, excluding intermediate-level waste. That is why the existing low-level radioactive waste level has been subdivided and the concentration limit value for intermediate-level waste has been changed in accordance with Nuclear Safety Commission Notice 2014-003. For the safe disposal of intermediate-level wastes, new optimization methodology for calculating the concentration limit of intermediate radioactive level wastes at an underground silo type disposal facility was developed. According to the developed optimization methodology, concentration limits of intermediate-level wastes were derived and the inventory of radioactive nuclides was evaluated. The operation and post closure scenarios were evaluated for the derived radioactive nuclide inventory and the results of all scenarios were confirmed to meet the regulatory limit. However, in case of $^{14}C$, it was confirmed that additional radioactivity limitation through a well scenario was needed in addition to the limit of disposal concentration. It was confirmed that the derived intermediate concentration limit of radioactive waste can be used as the intermediate-level waste concentration limit for the underground disposal facility. For the safe disposal of intermediate-level wastes, KORAD plans to acquire additional data from the radioactive waste generator and manage the cumulative radioactivity of $^{14}C$.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.2
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• pp.135-148
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• 2005

In the stage of conceptual design for the construction and operation of the geologic repository for radioactive wastes, it is important to consider a repository ventilation system which serves the repository working environment, hygiene & safety of the public at large, and will allow safe maintenance like moisture content elimination in repository for the duration of the repositories life, construction/operation/closure, also allowing safe waste transportation and emplacement. This paper describes the possible ventilation system design criteria and requirements for the prospective Korean radioactive waste repositories with emphasis on the underground rock cavity disposal method in the both cases of low & medium-level and high-level wastes. It was found that the most important concept is separate ventilation systems for the construction (development) and waste emplacement (storage) activities. In addition, ventilation network system modeling, natural ventilation, ventilation monitoring systems & real time ventilation simulation, and fire simulation & emergency system in the repository are briefly discussed.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.2
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• pp.89-96
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• 2014

The repository for the disposal of LILW which is generated from nuclear power plants and industries is expected to be completed in 2014. For the disposal of LILW, it is important to secure a disposal facility itself, but it is also very important to establish a reasonable charging system which all shareholders are satisfied with. Korea's disposal fee for LILW is higher than other countries' fee, which is a burden to waste generators as well as the waste management organization. The partial reason for the high disposal fee is put on the high social and construction cost when compared with other countries. However the major reason is put on the excessive borrowing cost that is used for the construction of the LILW disposal facility. In this study, we proposed the way to reduce the excessive borrowing cost for sustainable project managements of LILW disposal by analyzing a cost structure.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.583-588
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• 1996

방사성폐기물 처분후 처분장에서는 금속의 부시, 셀룰로스의 미생물분해, 방사선에 의한 분해등으로 인하여 기체가 발생하게 된다. 이 논문에서는 저준위 폐기물 수송시스템에서 고려하고 있는 폐기물모듈 개념중 6-Pack 모듈을 사용하여 치분할 때 기체발생에 미치는 영향을 평가하여 보았다. 계산은 방사성폐기물 처분장에 대한 초기 건설용량으로 고려중이었던 10만드럼 용량의 처분장을 기준으로 수행하였다. 평가결과, 6-Pack 모듈을 사용하여 처분할 때 6-pack 모듈을 사용하지 않고 처분하는 경우에 비해 H$_2$의 발생량은 1.4배 정도 증가하며, $CO_2$, CH$_4$ 등에 있어서는 영향이 거의 없는 것으로 나타났다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.4
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• pp.347-356
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• 2008

The purpose of Radioactive Waste Acceptance Criteria(WAC) is to verify a radioactive waste compliance with radioactive disposal facility requirements in order to maintain a disposal facility's performance objectives and to ensure its safety. To develop WAC which is conformable with domestic disposal site conditions, we furthermore analysed the WAC of foreign disposal sites similar to the Kyung-Ju disposal site and the characteristics of various wastes which are being generated from Korea nuclear facilities. Radioactive WAC was developed in the technical cooperation with the Korea Atomic Energy Research Institute in consideration of characteristics of the wastes which are being generated from various facilities, waste generators' opinions and other conditions. The established criteria was also discussed and verified at an advisory committee which was comprised of some experts from universities, institutes and the industry. So radioactive WAC was developed to accept all wastes which are being generated from various nuclear facilities as much as possible, ensuring the safety of a disposal facility. But this developed waste acceptance criteria is not a criteria to accept all the present wastes generated from various nuclear facilities, so waste generators must seek an alternative treatment method for wastes which were not worth disposing of, and then they must treat the wastes more to be acceptable at a disposal site. The radioactive disposal facility WAC will continuously complement certain criteria related to a disposal concentration limit for individual radionuclide in order to ensure a long-term safety.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.257-264
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• 2017

For the safe disposal of intermediate level radioactive waste according to the Nuclear Safety and Security Commission's notice and KORAD's management plan for low and intermediate level radioactive waste, the disposal concentration limit was derived based on the IAEA methodology. The evaluation of the derived disposal concentration limit revealed that it is not suitable as a practical limit for intermediate level radioactive waste. This is because the disposal concentration limit according to the IAEA methodology is derived using a single value of radioactive waste density and the disposal facility's volume. The IAEA methodology is suitable for setting the concentration limit for vault type disposal, which consists of a single type of waste, whereas an underground silo type disposal facility is composed of several types of radioactive waste, and thus the IAEA methodology has limitations in determining the disposal concentration limit. It is necessary to develop and apply an improved method to derive the disposal concentration limit for intermediate level radioactive waste by considering the radioactivity of various types of radioactive waste, the corresponding scenario evaluation results, and the regulatory limit.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.235-235
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• 2004

밀봉선원 폐기물은 크기가 작지만 특별한 관리 및 처분을 요하는 방사성폐기물이다. 특히 수거된 폐라듐선원의 경우 장기간의 관리가 필요하며, 음식물 보존이나 살균에 사용된 대형 밀봉선원 폐기물의 경우도 처분보다는 재활용도 고려하여야 한다. 이러한 밀봉선원의 특징은 작은 크기와 고건전성물질로 되어 있고 높은 비방사능을 갖는다는 것이며 따라서 처분시 보통의 방사성폐기물과는 달리 비균질폐기물의 특성을 고려한 안전성 평가가 필요하다.(중략)

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.4
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• pp.293-301
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• 2013

Borehole Disposal Concept (BDC) was initiated by the South African Nuclear Energy Corporation (NECSA) with the view to improve the radioactive waste management practices in Africa. At a time when geological disposal of radioactive waste is being considered, the need to protect ground water from possible radioactive contamination and the investigation of radionuclides migration through soil and rocks of zone of aeration into ground water has becomes very imperative. This is why the Borehole Disposal Concept (BDC) is being suggested to address the problem. The concept involves the conditioning and emplacement of disused sealed radioactive sources in an engineered facility of a relatively narrow diameter borehole (260 mm). Tanzania is operating a Radioactive Waste Management Facility where a number of spent sealed radioactive sources with long and short half lives are stored. The activity of spent sealed radioactive sources range from (1E-6 to 8.8E+3 Ci). However, the long term disposal solution is still a problem. This study therefore proposing the country to adopt the BDC, since the repository requires limited land area and has a low probability of human intrusion due to the small footprint of the borehole.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.3
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• pp.219-228
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• 2012

A long-term R&D program for HLW disposal technology development was launched in 1997 in Korea and Korea Reference disposal System(KRS) for spent fuels had been developed. After then, a recycling process for PWR spent fuels to get the reusable material such as uranium or TRU and to reduce the volume of radioactive waste, called Pyro-process, is being developed. This Pyro-process produces several kinds of wastes including metal waste and ceramic waste. In this study, the characteristics of the waste from Pyro-process and the concepts of a disposal container for the wastes were described. Based on these concepts, thermal analyses were carried out to determine a layout of the disposal area of the ceramic wastes which was classified as a high level waste and to develop the disposal system called A-KRS. The location of the final repository for A-KRS is not determined yet, thus to review the potential repository domains, the possible layout in the geological characteristics of KURT facility site was proposed. These results will be used in developing a repository system design and in performing the safety assessment.