[en] At present, radwastes of KAERI are managed under various divisions according to their generation characteristics and final disposal of radwastes of KAERI will be begun from 2015. So, effective management plan for KAERI radwastes is needed. As a short term management plan, classification and management of radwaste according to new category for radwaste, wrapping up treatment of radwaste generated from Seoul research reactor decommissioning and operation of WCP and management division were suggested. And as a mid term management plan, setting up disposal priority considering management division and radioactivity concentration of radwaste and enlargement of deposit for final disposal, and setting up disposal system for Ki-Jang research reactor were suggested. Finally, as a long term management plan, minimization and effective management of radwaste generated from decommissioning of nuclear fuel cycle facilities and operation of disposal system for intermediate level radwaste were suggested. The results of this study will be applied for preparation of foundation of effective final disposal plan for radwaste at KAERI and meeting national policy for radwaste and increasing public acceptance for KAERI.

[en] Recently, the amount of waste generated from mid- and low-level radioactive waste and regulatory clearance wastes have been increasing in the process of maintenance due to aging of nuclear facilities. Therefore, it is necessary to establish a technology and system for efficient and safe processing of these. In addition, the disposal performance of regulatory clearance wastes in KAERI is lower than that of other nuclear-related organizations in Korea (such as Korea Hydro & Nuclear Power, KEPCO, Korea Atomic Energy Authority) in terms of frequency and quantity. In the future, the amount of radioactive wastes generated will continue to increase and the need for continuous control of the management system will increase. Through this project, the procedures of the regulatory clearance wastes management are established and the temporary facility has been acquisited for the storage of the regulatory clearance wastes. The status of the wastes managed by each facility is identified and the treatment priority order is set. In addition, by carrying out large-scale maintenance and repair of radioactive waste treatment facilities and storage facilities, the management safety and treatment efficiency of low- and intermediate-level radioactive waste was increased, and the preparation of 1000 drums was possible for disposal site transfer. The Belgoprocess radioactive waste disposal facility in Belgium was also visited to find ways to improve the management system and facilities of advanced facilities

[en] There has been a recent increase in the type and amount of radwastes considered for regulatory clearance. Among the primary metal radwastes considered for regulatory clearance, pipe are particularly significant. it is difficult to identify contamination level of radioactive spent pipe, because of geometry of pipe. But, it is possible to conduct decontamination and representative sampling easily by developing a cutting and flattening machine for radioactive spent pipe. Economical effects like storage extension and resource recycling are expected by conducting regulatory clearance of radioactive spent pipe generated from nuclear facility operation and decommissioning process. By use of a cutting and flattening machine, disposal costs for radwastes will be saved. Additionally management of radwaste will be more efficient in view of storage capacity.

[en] Because of increase of the operation, extension of cycle and strengthening of regulation, technologies for the reduction of occupational radiation dose are necessary continually. As a basic study for the reduction of occupational radiation dose, in this study, the trends of the occupational dose in nuclear power plant at Kori site were analyzed. For the analysis, the radiation works are grouped as reactor related works, steam generator related works and pump and valve related works respectively. Also, the stream generator related works are subdivided to analyze the trends of each subdivided works

[en] The waste inventory records such as the activities and radio- nuclides contained in the waste packages are to be submitted with the radioactive wastes packages for the final disposal. The nearly around 10,000 drums of waste stocked in KAERI now should be assayed for the preparation of the waste inventory records too. For the successive execution of the waste assay, the investigation into the present waste assay techniques and equipment are to be taken first. Also the installation of the waste assay equipment through the comprehensive design, manufacturing and procurement should be proceeded timely. As the characteristics of the KAERI-stocked wastes are very different from that of the nuclear power plant and those have no regular waste streams, the application of the in-direct waste assay method using the scaling factors are not effective for the KAERI-generated wastes. Considering for the versal conveniency including the accuracy over the wide range of waste forms and the combination of assay time and sensitivity, the TGS(Tomographic Gamma Scanner) is appropriate as for the KAERI -generated radioactive waste assay equipment

[en] Although the criteria for the safety operation and the methodology for estimation of safety of power plant is improved, performance of the facility of nuclear power plants can be lowered due to the aging of the facility of each plant. A PSR(Periodic Safety Review) is required for the re-estimation of the safety and operability of each power plant and for the derivation of the improvement for each power plant. For the PSR, radiological safety of the power plant should be reviewed. In this study, Radiological Safety Performance Indicator for Korean Nuclear Power Plant is developed. The trend of each indicators are reviewed for the operation time of each nuclear power plant. As the data for the plant operation is limited, the overview for the trend of each indicator is restricted and further study for the trend analysis for each indicator is required

[en] Radioactive wastes generated during the decommissioning process and contaminated soils were transported and have been stored at the waste storage facility. The radioactivity in the wastes has been decayed a lot. The radionuclide and the activity concentration of stored soil wastes were reevaluated. And using the reevaluation results, the soil wastes were classified as either a regulatory clearance wastes or a radioactive waste. The storage space can be secured by storing regulatory clearance wastes in the extra storage facility and self disposing them. Also, the objective is to protect the environment from contamination by observing the related nuclear regulation and managing the radioactive wastes. Through the reevaluation of radioactivity and classification of contaminated soils, the unnecessary decontamination of uncontaminated soil was prevented. It allowed us to save the cost for decontamination and disposal, also we could secure the pretreatment process techniques such as how to sample and analyze the nuclide

[en] 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 γ-emitters. The total concentration of γ-emitters in soil is analyzed as about 0.01 ∼ 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

[en] Characteristics and states of management of low and intermediate level radioactive waste in site : state of management for each type of wastes, characteristics of low and intermediate level solid radioactive waste, stage of management of low and intermediate level solid radioactive waste. Survey of state of management and characteristics of low and intermediate level radioactive waste disposal facility in foreign countries : state of management of disposal facilities, classification criteria and target radionuclides for assessment in foreign disposal facilities. Survey of the assessment methods of the radionuclides inventory and establishing the direction of requirement : assessment methods of the radionuclides inventory, analysis of radionuclides assay system in KORI site, establishment the direction of requirement in the assessment methods

[en] In the radioactive waste storage facilities at the Korea Atomic Energy Research Institute (KAERI) in Daejoen, there are thousands drums of radioactive contaminated soil and concrete wastes. The soil and concrete wastes were generated in 1988 during the decommissioning process of the research reactor and the attached radioactive waste treatment facility which were located in Seoul. The wastes were transported to Daejeon and have been stored since then. At the generation time, the radioactive contamination of the wastes was very low, and the radionuclides in the wastes was Co-60 and Cs-137. As the wastes have been stored for more than 20 years, the radioactivity concentration of the wastes has been decayed to become very extremely low. The wastes are needed to be treated because they take up large spaces at the storage facility. Also by treating the wastes, final disposal cost can be saved. So, the regulatory clearance was considered as a treatment method for the soil and concrete wastes with extremely low radioactivity concentration