• Journal of Environmental Impact Assessment
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• v.23 no.4
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• pp.296-314
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• 2014

In recent years, Ministry of Environment (MOE) has been implementing a phased strengthening of the effluent standards for sewage treatment plants. In this regard, a comprehensive system should be developed to help check the appropriateness of such standards by specifying the grounds for standard-setting and investigating the current operation of sewage treatment plants clearly. It is necessary to establish a new standard-setting system for the effluent that is in a closer connection with the environmental criteria and rating systems. In the United States, the federal government provides guidelines on the least provisions and requirements for the Publicly Owned Treatment Works (POTWs). Local governments set the same or stricter guidelines that reflect the characteristics of each state. In Japan, the sewage treatment plants are subject to both the effluent standards and the discharge acceptable limits to pubic waters under the sewerage law. Specific requirements and limits are set in accordance with local government regulations. The European Union imposes sewage treatment plants with different provisions for effluent standards, depending on the sensitivity of public waters to eutrophication. The effluent standards for sewage treatment plants are classified by pollutant loads discharged to receiving waters. MOE also needs to introduce systems for setting new parameter standards on a POTW effluent by applying statistical means and treatment efficiencies or optimal treatment techniques, as seen in the cases of the US National Pollutant Discharge Elimination System (NPDES) or the EU Integrated Pollution Prevention and Control (IPPC).

• Journal of Korea Water Resources Association
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• v.53 no.spc1
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• pp.813-826
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• 2020

This study analyzes the effects of the Smart Water City (SWC) project that was introduced from 2014 to 2016 in Paju City, Gyeonggi Province, Korea, focusing on the achievement of the business goals. The SWC is referred to as a city that embraces a healthy water supply system based on Smart Water Management (SWM) that promotes the efficiency of water management by combining Information and Communication Technologies (ICTs) with water and sewerage facilities. In order to evaluate the effectiveness of the SWC project, this study deploys evaluation criteria corresponding to the project objectives, and analyzes the outputs before and after the project. The results show that the SWC has contributed to enhancing water supply services and the reliability and drinking rate of tap water. Specific improvement areas include the rise of average water flow rate and water leakage reduction, the diffusion of water quality monitoring system, and the reduction of floating particle concentration and turbidity in drainage pipes was achieved. These were possible because of specific implementation plans for clear goal setting and achievement and active services for citizens. The data related to water quantity and quality showed improved performance compared to before the introduction of SWMS, which is a positive effect. However, a quantitative analysis of the outputs has limitations in identifying other external factors that have led to the changes. In the future, guidelines for spreading SWC and more comprehensive and specific evaluation indicators for SWC should be prepared, and SWMS should be developed in consideration of the needs of users.

• Journal of Wetlands Research
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• v.21 no.4
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• pp.251-256
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• 2019

In the upstream and nearby areas of the water source, there are many areas where the sewerage penetration rate is relatively low due to development restrictions. This has been continuously affecting the pollution of the water source. As a measure to prevent this, method of distributing sewage and improving existing facilities are suggested. In this study, A MWTP(Municipal Watewater Treatment Plant) using the Air-vent SBR process located at upstream of An-dong and Im-ha Dam was selected as a modeling facility. And, the retrofit method to improve the effluent from RCSTP(Rural Community Sewage Tratment Plant) was induced based on A MWTP modeling result. The model construction and verification were carried out based on the operating data for 5 years (2012 ~ 2016). As a result, it was analyzed that the water quality of the effluent during the winter could be improved through control of cycle time in Air-vent SBR process and decreasing SRT (BOD: 1.8%, COD: 54.5%, SS: 4.3%, T-N; 0.8% and T-P: 7.7%). This research suggests that result of this research can be utilized as a retrofit method to improve the effluent overall treatment efficiency of the MWTP and the RCSTP which have similar operation process.

• Journal of Korea Water Resources Association
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• v.55 no.5
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• pp.357-370
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• 2022

This study aims to analyze the differences in performance according to various operation methods (direct management, public consignment, and private agency) of public sewage treatment facilities and derive the most efficient and high level of sewage treatment services to the public based on the research results. To this end, economic performance indicators (sewage treatment cost, sewerage rate) and social performance indicators (water quality, number of civil complaints) were selected, and cross-sectional analysis and longitudinal analysis were used to verify the difference between the averages of three or more groups through one-way ANOVA. As a result of the analysis, cross-sectional analysis, there was no difference in economic performance dimension according to the operating method, but in terms of social performance dimension, it was found that there was a difference according to the operating method. In the case of water quality indicators, the results were superior to those directly managed by public consignment and private agencies in the number of civil complaints. In the longitudinal analysis examining the improvement of performance indicators, there was no significant difference by operation method in most performance indicators. In order to improve the efficiency of public services and improve the service level, various approaches suitable for the characteristics of each service are required in addition to the logic of public consignment or introduction of private agency. In the future, when local governments promote public consignment or private agency, it is necessary to understand and promote the nature of the service, the specificity of each local government, and the needs of service users.

• Analyses & Alternatives
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• v.8 no.1
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• pp.87-109
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• 2024

At the 8th Party Congress in 2021, North Korea announced a plan to build 50,000 housing units in Pyongyang, and this paper analyzes the economic effects and related informal costs of of the project. Currently, Pyongyang is experiencing a significant housing shortage. It is estimated that the number of households in Pyongyang increased by 184,000 between 1994 and 2020, while the estimated new housing supply during the period was only 30,000. Pyongyang's 50,000 housing units construction project is characterized by the goal of improving the living conditions of workers, the application of the new city construction method, and the largest state-led housing construction since the Arduous March. The project is expected to generate economic effects such as increasing workers' motivation to work, increasing tourism resources, and generating income from related industries. On the one hand, a significant portion of the construction cost of the 50,000-unit housing project in Pyongyang is passed on to companies and households in the form of informal cost such as quasi-taxes and manpower mobilization. In addition, there may be congestion in the power supply and sewerage facilities that occur when moving in. If these costs are not taken into account, the feasibility of a housing construction project may not be properly assessed, making it difficult to sustain it in the long term.