• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.205-210
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• 2005

The proposed regulation for low and intermediate level radioactive waste disposal facility, scheduled to be revised, recommends that the waste generator should verify the radioactive waste conforms to the disposal requirements before disposing of it. According to the regulation, the radionuclide concentration of the radioactive waste, and its physical and chemical characteristics and safety must be confirmed prior to the disposal of low and intermediate level radioactive wastes, and the waste generator is required to deliver this information to the disposal facility operator. In addition, the disposal facility operator must assess the safety of the disposal site to establish the SWAC (Site Specific Waste Acceptance Criteria) in consideration of the characteristics of the site, whereas the waste generator must comply with the criteria in managing, disposing of and delivering low and intermediate level radioactive wastes. To abide by the afore-mentioned regulation and criteria, the waste generator must verify that the radioactive wastes to be disposed of are suitable for disposal before they are transported to the disposal facility, and to this end a radioactive waste certification program must be developed. This study conducted an in-depth analysis of the radioactive waste certification programs enforced in countries advanced in atomic energy to develop a draft of a certification program applicable to local power plants, and the program is currently applied as pilot to Uljin Power Plants No. 1 & 2 to prove its applicability. This study is going to analyze the results of the pilot application with a view to developing a radioactive waste certification program suitable to local conditions.

• Journal of Radiation Protection and Research
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• v.41 no.4
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• pp.315-327
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• 2016

Background: This study evaluated the atmospheric dispersion of radioactive material according to local weather conditions and emission conditions. Materials and Methods: Local weather conditions were defined as 8 patterns that frequently occur around the Kori Nuclear Power Plant and emission conditions were defined as 6 patterns from a combination of emission rates and the total number of particles of the $^{137}Cs$, using the WRF/HYSPLIT modeling system. Results and Discussion: The highest mean concentration of $^{137}Cs$ occurred at 0900 LST under the ME4_1 (main wind direction: SSW, daily average wind speed: $2.8ms^{-1}$), with a wide region of its high concentration due to the continuous wind changes between 0000 and 0900 LST; under the ME3 (NE, $4.1ms^{-1}$), the highest mean concentration of $^{137}Cs$ occurred at 1500 and 2100 LST with a narrow dispersion along a strong northeasterly wind. In the case of ME4_4 (S, $2.7ms^{-1}$), the highest mean concentration of $^{137}Cs$ occurred at 0300 LST because $^{137}Cs$ stayed around the KNPP under low wind speed and low boundary layer height. As for the emission conditions, EM1_3 and EM2_3 that had the maximum total number of particles showed the widest dispersion of $^{137}Cs$, while its highest mean concentration was estimated under the EM1_1 considering the relatively narrow dispersion and high emission rate. Conclusion: This study showed that even though an area may be located within the same radius around the Kori Nuclear Power Plant, the distribution and levels of $^{137}Cs$ concentration vary according to the change in time and space of weather conditions (the altitude of the atmospheric boundary layer, the horizontal and vertical distribution of the local winds, and the precipitation levels), the topography of the regions where $^{137}Cs$ is dispersed, the emission rate of $^{137}Cs$, and the number of emitted particles.

• The Journal of the Korea Contents Association
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• v.9 no.6
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• pp.247-255
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• 2009

This study aims to provide basic data for establishing the safety and health plan by investigating the exposure conditions in the facilities registering business about handling radiations and radioactive isotopes in Korea. dose levels(working space, worker location) of the workers in 153 facilities were measured using surveymeter, and individual exposure concentration[(shallow dose(SD), depth dose(DD)] in 27 facilities using thermal luminescence dosimeter(TLD). In accordance with the measurement results by business type[fire fighting prevention business(FFPB, n=10), financial insurance business(FIB, n=3) and other facilities(n=140)] using surveymeter, those three business type groups showed difference (p<0.000). Dose levels of worker location for FFPB and FIB were significantly higher than 10.0 ${\mu}Sv$/hr, the allowable standard for radiations and radioactive isotopes, and they were higher 109.3 times(p<0.000) and 187.5 times(p<0.000) than those in other facilities. The concentration of TLD[FFPB(n=10), other facility (n=17)] in DD of FFPB was significantly higher than that in other facility(p=0.05). In accordance with the analysis result on relationship between surveymeter and TLD, the dose on working space and worker location(r=0.406, p<0.05), worker location dose and SD(r=0.453, p<0.05), worker location dose and DD(r=0.553, p<0.01), and SD and DD(r=0.927, p<0.001) had all related each other. It is urgently required to change FFPB and FIB from the facilities requiring registration for handling radiations and radioactive isotopes to the facilities that shall get permission for handling radiations and radioactive isotopes by reestablishing the legal administration area, for safety and health of radiation occupants.

• Journal of the Korean Society of Radiology
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• v.12 no.3
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• pp.329-334
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• 2018

Radon which is natural component of air is a colorless and odorless radioactive gas. Radon exposure can also occur from some building materials if they are made from radon-containing substances by breathing. In this study, The radiation dose of radon concentration was detected at 8 buildings of the A university during 3-month from June. 2017 to August. 2017. We detected indoor radon exposure at 8 building of the university and estimated annual effective dose. The radon concentration of Hall G and Hall F of the A university represented 81 and $14Bq/m^3$ respectively and average indoor radon concentration represented $41.63Bq/m^3$. Average effective dose was estimated 0.40 mSv/y, maximum effective dose was 0.78 mSv/y and minimum effective dose was 0.13 mSv/y respectively. University is the place that students spend the almost whole time. We suggest ventilation and appropriate management of a building, which could reduce the natural radiation exposure by radon concentration.

• Journal of radiological science and technology
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• v.46 no.2
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• pp.141-149
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• 2023

The Korea Institute of Radiological and Medical Sciences plans to produce ²²⁵Ac, a therapeutic radio-pharmaceutical for precision oncology, such as prostate cancer. Radon, a radioactive gas, is generated by radium, the target material for producing ²²⁵Ac. The radon concentration is expected to be about 2000 Bq·m^-3. High-concentration radon-generating facilities must meet radioactive isotope emission standards by lowering the radon concentration. However, most existing studies concerning radon removal using activated carbon filters measured radon levels at concentrations lower than 1000 Bq·m^-3. This study measured ²²²Rn removal of coconut-based activated carbon filter under a high radon concentration of about 2000 Bq·m^-3. The ²²²Rn removal efficiency of activated carbon impregnated with triethylenediamine was also measured. As a result, the ²²²Rn removal amount of the activated carbon filter showed sufficient removal efficiency in a ²²²Rn concentration environment of about 2000 Bq·m^-3. In addition, despite an expectation of low radon reduction efficiency of Triethylenediamine-impregnated activated carbon, it was difficult to confirm a significant difference in the results. Therefore, it is considered that activated carbon can be used as a radioisotope exhaust filter regardless of whether or not Triethylenediamine is impregnated. The results of this study are expected to be used as primary data when building an air purification system for radiation safety management in facilities with radon concentrations of about 2000 Bq·m^-3.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.161-166
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• 2005

In KAERI, about 3,100 drums containing soil have been stored. The soils were generated from the decommissioning process of Seoul office in 1988. Those soils occupy about $27\%$ of the capacity of the radioactive waste storage facility and make it difficult to maintain the storage facility. The major radioactive nuclides contained in the soils were expected to be Co-60 and Cs-137. As 16 years have passed, the radioactivity of those nuclides have decayed a lot. In this study, as a basis of regulatory clearance, radionuclides and radioactivity concentration of soils were analyzed. As a result, there are only Co-60 and Cs-137 in soils as ${\gamma}-emitters$. The total concentration of ${\gamma}-emitters$ in soil is analyzed as about $0.01\;{\sim}\;0.12$ Bq/g. As the soils are expected to be regulatory cleared in 2009, those concentrations will decay to be less than 0.1 Bq/g. This concentration can be meet the regulatory criteria suggested by IAEA. The regulatory clearance will be proceeded based on not only the assessment results of environmental influence but also related regulations.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.243-248
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• 1998

This study investigated the separation and the property of palladium precipitate formed by ascorbic acid in a simulated radioactive liquid waste, which was composed of 10 elements((Pd, Ru, Rh, Nd, Cs, Sr, Fe, Ni, Zr, Mo). Pd was separated selectively by using reduction characteristics of metal ions contained in the simulated waste with ascorbic acid. When the nitric acid concentration was 0.5 M, the Pd over 99.5% was precipitated by adding 0.04 M ascorbic acid. Nitric acid concentration is important at the reduction reaction of Pd ion. The precipitation yield of Pd was decreased as the concentration of nitric acid was increased. The Pd precipitate was re-dissolved in reaching at an equilibrium when the concentration of nitric acid was high and ascorbic acid was added with a small amount. The Pd precipitate formed by ascorbic acid was Pd metal and was aggregated by particles less than $1.0{\mu}m$.

• Journal of Radiation Protection and Research
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• v.29 no.3
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• pp.205-212
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• 2004

Three-dimensional wind field and atmospheric dispersion models have been developed for estimating the concentration distributions of radioactive materials released into atmosphere. The field tracer experiment near the Kori nuclear power plant located over complex terrain was carried out for validating the atmospheric dispersion model. The wind fields were one of the most important factors for calculating the concentration. Therefore several numerical simulations using the measured wind data were performed to get more accurate concentration distributions compared with the analyzed values of the tracer gas. The calculated concentration distributions agreed well in the case of the usage of the more measured wind data in wind field model.

• Analytical Science and Technology
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• v.13 no.4
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• pp.474-483
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• 2000

An inductively coupled plasma atomic emission spectrometer/shielding system was specially designed and built for the analysis of radioactive materials. Both of an inductively coupled plasma source and a sample transfer system to be contacted with radioactive materials was installed in a stainless steel glove box. In terms of analytical capability and radiation safety, characteristic feature of the system was investigated. Its applicability to the determination of fission products and corrosion products in the radioactive materials such as spent fuel dissolver solution and the primary coolant of nuclear power reactors was evaluated. In the concentration range $0.01-0.1mgL^{-1}$, the relative standard deviation was found to be less than 5%.

• Nuclear Engineering and Technology
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• v.31 no.5
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• pp.506-511
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• 1999

The pilot system for radioactive liquid laundry waste was developed with treatment capacity, 1ton/hr and set up in the Yong Kwang unit #4. The system is composed of tank module, RO systems and a UV/$H_2O$$_2$photo-oxidation unit. The RO system consists of the BW unit (low-pressure RO for brackish water desalination) and the SW unit (high-pressure RO for seawater desalination). The BW unit possesses 4 RO membranes and it can reduce the feed water volume down to 1/10. This concentrated feed water can be reduced again up to 1/10 in its volume in the SW unit composed of 4 RO membranes. The UV/$H_2O$$_2$ photo-oxidation process unit was used for the detergent degradation. The operation of the pilot system was carried out and verified in its capability through the continuous operation and concentration operation using the actual liquid waste from the power plant. The design criteria and data for industrialization were yielded. The efficiency of the UV/$H_2O$$_2$ photo-oxidation process and the optimum operational procedure were evaluated. The decontamination factors for radioactive cobalt and cesium were measured. This on-site test showed the experimental result in the DF$\geq$300 and volume reduction factor$\geq$100.