• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.25-32
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• 1998

Tritium is released into the environment as various form but HTO is most relevant to the incorporation of tritium into living organisms and to the formation of OBT. Tritiated compounds may be transported to humans via several tropic levels. Retention times of organically bound tritium in organisms are considerably longer than those of tritiated water, which has significant consequences on exposure dose estimation. It is rather difficult to predict the amount of OBT produced by the photosynthetic process of plants because it may be influenced by a multitude of environmental factors and plant parameters. Tritiated organic matters are classified as the exchangeable or nonexchangeable bound tritium according to the bound form. After short term HTO exposure in plants, the formation and uptake of OBT were evaluated.

• Journal of Radiation Protection and Research
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• v.28 no.4
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• pp.337-342
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• 2003

On a basis of the washout model and concentrations of anthropogenic tritium in rainwater around the Wolsong site, the washout coefficients of tritium by rainwater were calculated, and the validity of washout deposition model are estimated. As the result of that, the washout coefficients in 10 sampling stations around Wolsong site were in the range of $2.9{\times}10^{-5}\;-\;16{\times}10^{-5}\;s^{-1}$ with the mean value of $7.21{\times}10^{-5}\;s^{-1}$. The validity of the washout deposition model was confirmed by comparing the observed data with the calculated ones.

• Progress in Medical Physics
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• v.5 no.1
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• pp.75-85
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• 1994

As we enter the 2000s, there are four nuclear power units of the pressurized heavy water reactor-type in the commercial operation at the Wolsung Nuclear Power Plant(NPP) site where a larger amount of tritium ($\^$3/H) is released inevitably to the site environment. This radioctive nuclide is easily distributed throghout our environment because of its ubiquitous form as tritiated water (HTO) and its persistence in the environment. Tritum has certain characterisitics that present unique challenges for beta radiation dosimety and health risk assesment. In this paper, therefore, a variety of matters on tritium are considered and reviewed in terms of its characteristics and sources, metabolism and dosimetry, microdosimetry, radiobiology, risk assessment, and transport and cycling in the environment, etc.

• Journal of Radiation Protection and Research
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• v.23 no.2
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• pp.75-82
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• 1998

Tritium concentration in the atmosphere during HTO exposure was different between two experiments due to different velocity of HTO evaporation. Assimilation rate of the rice plant was considered to be higher than that of Chinese cabbage The uptake of atmospheric HTO into tissue free water tritium(TFWT) was higher in rice plants than in Chinese cabbage. However, organically bound tritium(OBT) concentration is relatively higher in Chinese cabbage than in rice. The specific activity ratio(SAR) increased slowly after HTO exposure and decreased gradually with time. The behaviour of HTO in the soil was affected by the environmental conditions.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.3
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• pp.149-159
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• 2011

Nuclear power utilities should establish a site-specific groundwater monitoring program for early detection of unplanned radioactive material's releases which can occur due to degradation of systems, structures and components of the nuclear power plants in order to keep the impact of the unplanned releases on the environment and the residents as low as reasonably achievable. For this end, groundwater flow on site should be evaluated based on characterization of the hydrogeology of a site of concern. This paper aims to provide data necessary for establishing groundwater monitoring program which is currently considered at Kori nuclear power plant 1 by characterizing groundwater flow system on the site based on the existing hydrogeological studies and related documents, and by modeling tritium transport. The results showed that the major groundwater flow direction was south-west and that most of groundwater entered a southern and eastern seas. Although the tritium plume also released into the sea, its rate was delayed by dewatering sump.

• Journal of Radiation Protection and Research
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• v.34 no.4
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• pp.184-189
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• 2009

In pressurized heavy water reactors, workers who enter radiation controlled areas must submit their urine samples to health physicists after radiation work; these samples are then used to monitor internal radiation exposure from tritium intake. This procedure assumes that the samples submitted represent tritium concentration inside the body at equilibrium. According to both technical reports from the International Commission on Radiological Protection and experimental results from Canadian nuclear utilities, tritium inside the body generally reaches equilibrium concentration after approximately 2-3 hours of intake. In practice, urine samples can be submitted either before the 2 hours mark or after several hours of radiation work because of the numerous tasks that workers must perform and their frequent entries during nuclear power plant maintenance. In this paper, tritium concentration in workers' urine samples was measured as a function of time submitted after radiation work. Based on the measurement results, changes in the tritium concentration inside the body and its effect on internal dose assessment were then analyzed. As a result, it was found that tritium concentration reaches equilibrium concentration before the 2 hours mark for most workers' urine samples.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.972-973
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• 2005

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.314-314
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• 2010

For the optimal design of a tokamak-type reactor, self-consistent determination of a radial build of reactor systems is important and the radial build has to be determined by considering the plasma physics and engineering constraints which inter-relate various reactor systems. In a low aspect ratio (LAR) tokamak reactor with a superconducting toroidal field (TF) coil, the shield should provide sufficient protection for the superconducting TF coil and the shield plays a key role in determining the size of a reactor. To determine the radial build of a reactor, neutronic effects such as tritium breeding in the blanket, nuclear heating, and radiation damage to toroidal field (TF) coil has to be included in the systems analysis. In this work, the outboard blanket only is considered where tritium self-sufficiency is possible by using an inboard neutron reflector instead of breeding blanket. The reflecting shield should provide not only protection for the superconducting TF coil but also improved neutron economy for the tritium breeding in outboard blanket. Tungsten carbide, metal hydride such as titanium hydride and zirconium hydride can be used for improved shielding performance and thus smaller shield thickness. With the use of advanced technology in the shield, conceptual design of a compact superconducting LAR reactor with aspect ratio of less than 2 will be presented as a viable power plant.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.304.1-304
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• 2001

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.02a
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• pp.64-72
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• 2004

The dryer (ten per unit) are operating to remove tritium in PHWR(Pressurized Heavy Water Reactor). There are coming out heavy water adsorbent from operating the dryer (95 drums for ten year per unit) The amount of radioactivity of heavy water adsorbent almost exceed ninety times more than disposal limit-in-itself showed by The Ministry of Science and Technology. It has to be disposed whole radioactive waste products, however there are problems of increase at the expense of their permanent disposal. In this research, We have studied how to remove kinds of nuclear materials and amount of tritium with in heavy water adsorbent. As the result we could develop disposal equipment and apply it. D20 adsorbent have to contain below Gamma nuclide O.3Bq/g and tritium 100Bq/g "The Regulation for disposal of the radioactivity wastes" showed by The Ministry of Science and Technology. There fore. So as to remove amount of tritium and kinds of nuclear materials (DTO) we needed a equipment. Also we have studied how to remove effectively radioactivity with in Adsorbent. As cleaning heavy water adsorbent and drying on each condition (temperature for drying and hours for cleaning). Because there is something to return heavy water adsorbent by removing impurities within adsorbent when it is dried o high temperature. After operating, we have been applying this research to the way to dispose heavy water adsorbent. Through this we could reduce solid waste products and the expense of permanent disposal of radioactive waste products and also we could contribute nuclear power plant run safely. According to the result we could keep the best condition of radiation safety super vision and we could help people believe in safety with Radioactivity wastes control for harmony with Environment.