• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.646-652
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• 2014

Data of pollution incidents which occurred in shipyards of South Korea for 10 years from 2004 to 2013 were collected and analyzed in order to propose the plans for the prevention of pollution incidents in shipyards. Total number of pollution incidents in shipyards was 103 cases over the nation of Korea for the recent 10 years and the average annual number was about 10 cases, and annual cases tended to increase from 8 cases in 2004 to 23 cases in 2010 and then to decrease to 9 cases in 2013. The location data of pollution incidents showed 32 cases in Busan metropolitan city (31%), 30 cases in Jeonnam (29%), 21 cases in Gyeongam (21%), 5 cases in Jeju (5%), 4 cases in Gangwon (4%), 4 cases in Gyeongbuk (4%), 3 cases in Chungnam (3%) and 3 cases in Incheon metropolitan city (3%). According to the data of work types of shipyards, 60 cases happened during the work of ship repair (58%), 25 cases during the work of ship breakup (24%), 10 cases in the course of ship building (10%) and 8 cases by others (8%). The data of pollutant type showed oil and oily mixtures to be 59 cases (57%), waste paint dust to be 22 cases (21%), iron dust and welding slag to be 13 cases (13%), wastes to be 4 cases (4%), waste FRP powder to be 3 cases (3%), and others to be 2 cases (2%). The plans for the prevention of pollution incidents in shipyards of Korea were proposed as follows; (1) Observance of the related laws and regulations, (2) Establishment and implementation of action plans to prevent areas dense with shipyards from causing pollution incidents, (3) Establishment and implementation of oil pollution prevention plans in shipyards, especially during the ship repair and breakup works, (4) Preparation of measures to solve civil complaints against pollution incidents in shipyards, and (5) Improvement in national management for the control of shipyards.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.9-17
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• 2015

In order to elucidate the current state of marine pollution of heavy metals around major shipyards in Korea, seawater samples were collected at eleven sampling stations and four control stations around 4 major shipyards located in the southeastern coast of Korea in summer 2010, and 6 kinds of metals such as copper(Cu), zinc(Zn), iron(Fe), cadmium(Cd), lead(Pb) and mercury(Hg) in seawater samples were analyzed. The analyses of heavy metals in seawater showed that the mean Cu concentrations in seawater around 4 major shipyards were in the range of $0.817{\sim}1.638{\mu}g/L$ which were lower than Korean environmental standards of $20{\mu}g/L$ for the protection of human health(PHH) and of $3{\mu}g/L$ for short-term protection of marine ecosystem(SPME) but higher than Cu concentration at control station by a factor of up to 2.75. The mean Zn concentrations were in the range of $0.228{\sim}0.567{\mu}g/L$ which were lower than Korean environmental standards of $100{\mu}g/L$ for PHH and $34{\mu}g/L$ for SPME but higher than Zn concentration at control station by a factor of up to 5.91. The mean Fe concentrations were in the range of $3.332{\sim}7.410{\mu}g/L$ which were higher than Fe concentration at control station by a factor of up to 6.75. The mean Cd concentrations were in the range of $0.013{\sim}0.028{\mu}g/L$ which were lower than Korean environmental standards of $10{\mu}g/L$ for PHH and $19{\mu}g/L$ for SPME but higher than Cd concentration at control station by a factor of up to 2.33. The mean Pb concentrations were in the range of $0.007{\sim}0.126{\mu}g/L$ which were lower than Korean environmental standards of $50{\mu}g/L$ for PHH and $7.6{\mu}g/L$ for SPME. The mean Hg concentrations were in the range of $0.002{\sim}0.004{\mu}g/L$ which were lower than Korean environmental standards of $0.5{\mu}g/L$ for PHH and $1.8{\mu}g/L$ for SPME. Although the concentrations of metals such as Cu, Zn and Fe which were used in shipbuilding works were lower than Korean environmental standards for PHH and SPME, the fact that the concentrations of Cu, Zn and Fe at sampling stations around major shipyards were higher than those at control stations implies that the works in shipyards had some effects on marine water quality around shipyards. Therefore, marine environment management such as the prevention and control of the discharge of various pollutants from shipyards is required on national level.

• Journal of the Korea Concrete Institute
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• v.25 no.3
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• pp.321-329
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• 2013

Recently, the medium-low level radioactive waste from nuclear power plant must be transported from temporary storage to the final repository. Medium-low level radioactive waste, which is composed mainly of the liquid ion exchange resin, has been consolidated with cementitious material in the plastic or iron container. Since cementitious material is brittle, it would generate cracks by impact load during transportation, signifying leakage of radioactive ray. In order to design the safety transporting equipment, there is a need to check the compressive strength of the current waste. However, because it is impossible to measure strength by direct method due to leakage of radioactive ray, we will estimate the strength indirectly by the dynamic modulus of elasticity. Therefore, it must be identified the relationship between of strength and dynamic modulus of elasticity. According to the waste acceptance criteria, the compressive strength of cement based solid is defined as more than 3.44 MPa (500 psi). Compressive strength of the present solid is likely to be significantly higher than this baseline because of continuous hydration of cement during long period. On this background, we have tried to produce the specimens of the 28 day's compressive strength of 3 to 30 MPa having the same material composition as the solid product for the medium-low level radioactive waste, and analyze the relationship between the strength and the dynamic modulus of elasticity. By controling the addition rates of AE agent, we made the mixture containing the ion exchange resin and showing the target compressive strength (3~30 MPa). The dynamic modulus of elasticity of this mixtures is 4.1~10.2 GPa, about 20 GPa lower in the equivalent compressive strength level than that of ordinary concrete, and increasing the discrepancy according to increase strength. The compressive strength and the dynamic modulus of elasticity show the liner relationship.