• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.2
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• pp.245-261
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• 2019

Radioactive contaminant from a nuclear facility moves to the ecosystem by run-off or groundwater flow. Among the two mechanisms, contaminant plume through a river can be easily detected through a surface water monitoring system, but radioactive contaminant transport in groundwater is difficult to monitor because of lack of information on flow path. To understand the contaminant flow in groundwater, understanding of the geo-environment is needed. We suggest a method to decide on monitoring location and points around an imaginary nuclear facility by using the results of site characterization in the study area. To decide the location of a monitoring well, groundwater flow modeling around the study area was conducted. The results show that, taking account of groundwater flow direction, the monitoring well should be located at the downstream area. Also, monitoring sections in the monitoring well were selected, points at which groundwater moves fast through the flow path. The method suggested in the study will be widely used to detect potential groundwater contamination in the field of oil storage caverns, pollution by agricultural use, as well as nuclear use facilities including nuclear power plants.

• Clean Technology
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• v.26 no.4
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• pp.239-250
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• 2020

Biomass is an abundant renewable energy resource that can replace fossil fuels for the reduction of greenhouse gas (GHG). Indonesia has a large number of cheap biomass feedstocks, such as reforestation (waste wood) and palm residues (empty fruit bunch or EFB). In general, raw biomass contains more than 20% moisture and lacks calorific value, energy density, grindability, and combustion efficiency. Those properties are not acceptable fuel attributes as the conditions currently stand. Recently, torrefaction facilities, especially in European countries, have been built to upgrade raw biomass to solid fuel with high quality. In Korea, there is no significant market for torrefied solid fuel (co-firing) made of biomass residues, and only the wood pellet market presently thrives (~ 2 million ton yr-1). However, increasing demand for an upgraded solid fuel exists. In Indonesia, torrefied woody residues as co-firing fuel are economically feasible under the governmental promotion of renewable energy such as in feed-in-tariff (FIT). EFB, one of the chief palm residues, could replace coal in cement kiln when the emission trading system (ETS) and clean development mechanism (CDM) system are implemented. However, technical issues such as slagging (alkali metal) and corrosion (chlorine) should be addressed to utilize torrefied EFB at a pulverized coal boiler.

• Tunnel and Underground Space
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• v.33 no.5
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• pp.312-338
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• 2023

The underground disposal facility for spent nuclear fuel demands a specialized design, distinct from conventional practices, to ensure long-term thermal, mechanical, and hydraulic integrity, preventing the release of radioactive isotopes from high-temperature spent nuclear fuel. SKB has established design criteria for such facilities and executed practical design implementations for Forsmark. Moreover, in response to subsurface uncertainty, SKB has proposed an empirical approach involving monitoring and adaptive design modifications, alongside stepwise development. SKB has further introduced a unique support system, categorizing ground types and behaviors and aligning them with corresponding support types to confirm safety through comparative analyses against existing systems. POSIVA has pursued a comparable approach, developing a support system for Onkalo while accounting for distinct geological characteristics compared to Forsmark. This demonstrates the potential for domestic implementation of spent nuclear fuel disposal facility designs and the establishment of a support system adapted to national attributes.

• Tunnel and Underground Space
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• v.34 no.2
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• pp.104-126
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• 2024

Buffer and backfill play an essential role in isolating high-level radioactive waste and retard the migration of leaked radionuclides in deep geological disposal system. A bentonite mixture, which exhibits a swelling property, is considered for buffer and backfill materials, and excessive groundwater inflow from surrounding rock mass may affect stability and efficiency of their role as an engineered barrier. Therefore, stringent quality control as well as in-situ installation management and inflow water constrol for buffer and backfill are required to ensure the safety of deep disposal facilities. In this study, we analyzed the design requirements of buffer and backfill by examining various laboratory tests and a field study of the Steel Tunnel Test at the Äspö Hard Rock Laboratory in Sweden. We introduced how to control the quality of buffer and backfill construction in-field, and also presented how to handle excessive groundwater inflow into disposal caverns, validating the groundwater retention capacity of bentonite pellets and the effectiveness of geotexile use.

• Journal of the Korean Society of School Health
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• v.2 no.1
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• pp.91-107
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• 1989

This study was designed to evaluate current level of school health practice in Chonbuk province and to analyze the relationship between school health practice and variables. All the subjects in this study were 140 schools themselves in Chonbuk province. Survey data was collected through the interviewed checklists from the widly accepted school health responsibilities of administration and practice and the direct observation by the interviewer. It was conducted from 1st of Nov. to 17 th of Dec, 1988. The major findings of this study are as follows: A. Level of school health practice was relatively low in score (Mean=64.5). $\cdot$ Healthful School Living -76.14 $\cdot$ School Health Service -71.29 $\cdot$ School Health Instruction -47.98 B. Strengths and Weakness field in School Health Practice. 1. Healthful School Living: Strengths: Waste disposal, Seating, Playground. Weakness: School site, Safety control. 2. School Health Service : Strenths : Health Appraisal, Follow up and Counseling. Weakness: Dental Health, Prevention and Control of Communicable Disease, Facilities and Equipment of Health Clinic. 3. School Health Instruction : Strength : None, Weakness : Program Organization, Curriculum Planning and Evaluation, Curriculum Content, Instructional Aids. C. Significance between degree of School Health Practice and Variables. 1. Healthful School Living : (1) Toilet : Area (p<0.001), No.of Class (p<0.001), School Nurse (p<0.05) (2) Water Supply : School Nurse (p<0.05) (3) Safety Control : School Nurse (p<0.05) 2. School Health Service : (1) Health Appraisal : School Nurse (p<0.05) (2) Follow up and Counseling : School Nurse (p<0.001) (3) Dental Health : Area (p<0.05), Level of School (p<0.05) (4) Prevention and Control of Communicable Disease : Level of School (p<0.001), School Nurse (p<0.05) (5) Emergency Care : Area (p<0.001), No. of Class (p<0.001), School Nurse(p<0.001) (6) Facilities and Equipment of Clinic : Level of School (p<0.001), No.of Class (p<0.001), School Nurse (p<0.001) 3. School Health Instruction: (1) Program Organization : No. of Class (p<0.05), School Nurse (p<0.001) (2) Curriculum Planning land Evaluation : School Nurse (p<0.001) (3) Instructional Aids : Level of School (p<0.001), School Nurse (p<0.05) Recommendation for the Improvement of School Health Practice are as follows : A. There should be further study to strengthen the school health practice, especially in the field of school health instruction. B. It is strictly required to employ and utilize school nurse at each school level not only for the school health service but also for the school health in struction. C. There should be much considerations about adequate size and easily accessible distance in school site.

• Journal of Radiation Protection and Research
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• v.39 no.1
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• pp.61-64
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• 2014

Radioactive materials are in use and have many applications from the generation of electricity to the purposes of research, industry and medicine such as diagnosis and therapy. In the course of their use some of radioactive substances may be discharged into the environment from facilities using the unsealed radioactive materials, which are main artificial sources occurring the public exposure. Discharges are in the form of gases, particles or liquids. This paper provides procedures to estimate the level of the public exposure based on the conservative assumptions and simple calculations in the facility using unsealed liquid sources. They consist of two processes; (1) to calculate maximum concentration of gaseous effluents discharged through the exhaust pipe and average concentration of liquid effluents discharged through the drain of the storage tank, (2) to compare each of them to numerical guidances for the discharges of radioactive gaseous and liquid effluents mentioned in the related notification. For this purpose followings are assumed properly; daily usage, form and dispersion rate of radionuclides, daily amount of radioactive liquid waste and exhaust and drainage equipment. The procedures are readily applicable to evaluate environmental effects by planned effluent discharges from facilities using the unsealed radioactive materials. In addition they may be utilized to obtain practical requirements for radiation safety control necessary for the reductions of the public exposure.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.2
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• pp.211-221
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• 2012

The Ministry of Environment will enforce air quality standards for $PM_{2.5}$ in 2015 because it affects human health as well as climate change and brings about other adverse effects. Until recently, even though a number of researches have reported $PM_{2.5}$ emissions according to sources, they have not precisely considered the emission factors correspondent to each source for emission estimation. For the sake of establishing $PM_{2.5}$ emission inventories, this study was undertaken using activity data of each source taken from CAPSS (Clean Air Policy Support System) multiplied by each emission factor of U.S. EPA Speciate or EEA CORINAIR. The 2008's total annual $PM_{2.5}$ emission (73.971 ton/yr) can be apportioned into five sources, such as fuel combustion facilities (62.2%), mobiles (33.8%), production processes (3.2%), fires (0.4%), and waste treatments (0.3%). The results show that fuel combustion facilities and mobiles are the predominant sources of $PM_{2.5}$, and they should be taken into great account in establishing $PM_{2.5}$ standards. In addition, it is necessary and urgent to develop effective measures for reduction of $PM_{2.5}$ emissions from those two main sources as well.

• Journal of environmental and Sanitary engineering
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• v.22 no.1 s.63
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• pp.1-16
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• 2007

The incineration process has commonly used for wastes amount reduction and thermal treatments of pollutants as the technologies accumulated. However, the process is getting negative public images owing to matter of hazardous pollutants emission. Specially dioxins became a main issue and is mostly emitted from municipal solid wastes incineration. In this reason, pyrolysis/gasfication/melting process is presented as a alternative of incineration process. The pyrolysis/gasfication/melting process, a novel technology, is middle of verification of commercial plant and development of technologies in Korea. But the survey about the pollutant emission from the process, and background data in these facilities is necessary. So in this survey, it Is investigated that the behavior of dioxins in three pyrolysis/gasfication/melting plant (S, T, P) of pilot scale. In case of S plant, concentration of dioxins shows high at latter part of cogenerated boiler and stack which are operate on low temperature conditions than a latter parts of pyrolysis and melting furnace which are operate on high temperature condition. Concentration of gas phage dioxins had increased after combusted gas passed cogenerated boiler and this is attributed to react of precursor materials such as chlorobenzene and chlorophenol. Concentration of dioxins in T plant showed lower levels at latter part of cooling equipment which are operate with water spray type on low temperature conditions than a latter parts of gasfied melting furnace which are operate on high temperature condition. Removal efficiency of dioxins at gas treatment equipment was 78.8 %. Concentration of dioxins in P plant was low at latter part of SDA/BF which is operate at low temperature conditions than a latter parts of pyrolysis gasfied chamber which are operate at high temperature condition. Removal efficiency of dioxins of SDA/BF was 85.9 % and therefore, it showed high efficiency at those of stoker type incineration facility. However, concentration of dioxins which emitted at high temperature condition were low in three facilities and satisfied present standard emission level of dioxins. To consider the distribution ratio of dioxins, Particulate phase dioxins at S and P plants showed similar ratio with which shows in current stoker type for middle scale domestic waste incineration facility. It is necessary to continuos monitoring the ratio of distribution of dioxins in T plant in because ratio of gas phage dioxins showed high.

• Journal of Korean Society of Transportation
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• v.36 no.1
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• pp.23-37
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• 2018

In recent years, it is very difficult to construct and expand new infrastructures in a city center because of long-term low growth and lack of space due to urban overcrowding. So, there is a need to study a variety of Retrofitting techniques and urban applications that can lead to sustainable development while efficiently utilizing existing facilities. 'Retrofit' means a sustainable urban retrofitting as a directed alteration of the structures, formations and systems of existing facilities to improve energy, water and waste efficiencies. In this study, we applied a hierarchical network design technique that can reflect the structural hierarchy of a city to study how to retrofit public transportation routes in Seoul. The hierarchical network design means dividing the hierarchy according to the functions of hubs and connecting different hierarchies to form a hierarchical network. As a result of comparing the application results of various retrofitting scenarios of public transport, the differences of daily PKT and PHT by about 2.6~3.2% less than before the improvement address that the convenience of passengers is increased. Therefore, it is expected that if the route planning is established according to the proposed method, it will increase the number of passengers and the operational efficiency by the improved convenience of public transit passengers.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.141-151
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• 2016

Recently, technology for energy recovery from waste has been increasing interest globally including the Korea. In Korea, we have interested in using biogas generated from the sewage treatment process. As one alternative, there are operating biogas combined heat and power plant. The generation amount of the Sewage Sludge are expected to grow in the future. For this reason, total processing cost of Sewage Sludge will increase. To solve this problem, it seems will be invested with the expansion of facilities that use biogas as energy. Therefore, quantitative information on such facilities is required. Thus, this study attempts to economic feasibility analysis for Seonam Biogas Combined Heat and Power Plant. Meanwhile, as the benefit items for economic feasibility analysis consider electricity supply benefit except for heat supply benefit. The average prices of electricity use were residence 123.69, commercial 130.46, and industry 102.59 won per kWh for the year 2015, In addition, the economic benefit are calculated to be residence 310.21, commercial 378.49, and industry 222.87 won per kWh. The results of economic feasibility analysis is NPV 72.18 billion won, B/C 1.90, IRR 37%, shows that economic validity of Seonam Biogas Combined Heat and Power Plant.