The number, size, and material distribution of microplastics (MPs) sized 20-200 μm in the raw water and water treatment processes were analyzed using FT-IR in three water treatment plants in Jeju Province. The number of MPs was detected at 0.075-0.620 MP/L in raw water and 0.040-0.047 MP/L in filtered water, which is relatively lower than the results of other studies. Regarding the size of the MPs, particles sized 20-50 μm in both the raw water and the treated water accounted for the highest proportion, representing 65.6% and 56.3% of the total, respectively. In terms of MP type distribution, polypropylene (PP) was identified as the main type at 58.7%. In the water purification process, the MPs removal efficiency was the highest at 93.5% in the sedimentation and rapid filtration process, followed by 58.4% in membrane filtration and 40.0% in slow filtration. Continuous monitoring of the distribution of MPs in raw water and water treatment processes is recommended.

Risk assessment on Jeju Special Self-Governing Province(JSSGP)’s water supply facilities and establishment of adaptation measures for climate crisis factors were implemented. JSSGP’s vulnerability to the climate crisis was high in the order of drought, heat wave, heavy rain and strong wind. As a drought adaptation measure, policies of water saving and revenue water ratio improvement were considered. As for the heat wave adaptation measure, the introduction of an advanced water treatment process was suggested in response to the increase of algae cell number which resulting in taste and odor problem. As for heavy rain adaptation measures, the installation and operation of automatic coagulant injection devices for water purification plants that take turbid surface water were proposed. As a measure to adapt to strong winds, stabilization of power supply such as installation of dual power line was proposed in preparation for power outages. It is expected that water facilities will be able to supply high-quality tap water to customers even under extreme climate conditions without interruption through risk assessment for climate crisis factors and active implementation of adaptation measures.

To improve the safety of tap water, a study was conducted on the introduction of sanitation safety certification system for water treatment plants(WTPs). In order to produce and supply safe tap, the inflow of pollutants should be blocked as much as possible during the tap water production process, and contaminated materials should be removed or inactivated to a safe level in the WTPs. In order to block the inflow of pollutants in WTPs, it is necessary to strengthen the sanitation management such as installation of facilities for preventing inflow and habitat of larvae, and to remove or inactivate pollutants in the tap water production process, strengthening the safety management such as enhanced turbidity management is needed. Sanitation and safety management in the WTPs can be significantly improved by introducing certification system of WTPs. This will induce continuous improvement in water purification plants with insufficient sanitation and safety management, and provide incentives for WTPs with good sanitation and safety management. In addition, when the WTPs sanitation and safety certification system is established, it is desirable to expand the proposed system from WTPs to the entire process of tap water production and supply.

This paper investigates the current status of Jeju special self-governing province (JSSGP)’s water infrastructure and recommends directions for improvement. JSSGP relies on groundwater for most of its water resources. Recently, water usage has been steadily increasing due to the increase of residents and tourists while the quality of groundwater has been steadily worsening. Deterioration in water quality of groundwater can be seen through the increase in concentration of nitrate nitrogen and microorganisms. To overcome such problems, water consumption must be reduced by water demand management in all fields including residential and agricultural water use. The quality of water resources should be preserved through the management of pollutants. For efficient management of water resources, great efforts should be made to reduce the leakage rates in household and agricultural water, which is currently at the highest level in the country. Furthermore, diversification of water intake sources other than groundwater is needed, especially for agricultural water supply. For water and sewerage facilities, compliance with drinking water quality standards and discharge water quality standards must be achieved through the optimization of operation management. This process requires recruiting professionals, improving existing workers' expertise, and improving facilities.

In this study, effects of five raw water quality parameters (turbidity, odor compounds caused by algae, filter clogging caused by algae, pH increase caused by algae, and organic matter) on improvements and operations costs of typical water treatment plant (WTP) were estimated. The raw water quality parameters were assumed the worst possible conditions based on the past data and costs were subsequently estimated. Results showed that new water treatment facilities were needed, such as a selective intake system, an advanced water treatment processes, a dual media filter, a carbonation facility, and a re-chlorination facility depending on water quality. Furthermore, changes needed to be made in WTP operations, such as adding powered activated carbon, increasing the injection of chlorine, adding coagulation aid, increasing the discharge of backwashed water, and increasing the operation time of dewatering facilities. Such findings showed that to reliably produce high-quality tap water and reduce water treatment costs, continuous improvements to the quality of water sources are needed.

One of the most effective methods to consistently ensure the safety of a tap water supply can be achieved by application of a comprehensive risk assessment and risk management approach for drinking water supply systems. This approach can be termed water safety plans(WSP) which recommended by WHO(world health organization) and IWA(international water association). For the introduction of WSP into Korea, 150 hazards were identified all steps in drinking water supply from catchment to consumer and risk assessment tool based on frequency and consequence of hazards were developed. Then, developed risk assessment tool by this research was implemented at a water treatment plant(Q=25,000 m3/d) to verify its applicability, and several amendments were recommended; classification of water source should be changed from groundwater to stream to strengthen water quality monitoring contaminants and frequencies; installation of aquarium to monitor intrusion of toxic substances into raw water; relocation or new installation on-line water quality analyzers for efficient water quality monitoring; change of chlorination chemical from solid phase(Ca(OCl)2) to liquid phase(NaOCl) to improve soundness of chlorination. It was also meaningful to propose hazards and risk assessment tool appropriate for Korea drinking water supply systems through this research which has been inconsistent among water treatment authorities. Key words: Hazard, Reliability, Risk management, Water safety plan, Tap water

Climate adaptation strategies for water utilities including 16 water treatment plants(WTPs) in Jeju were investigated. Drought, heat wave, and heavy rain were among the most significant climate factors affecting water utilities in Jeju. Heat wave increases water temperature, which in turn increases the concentration of algae, color, and odor materials. Some adaption strategies for the heat wave can be strengthening water monitoring and introducing advanced water treatments. Heavy rain increases raw water turbidity in surface water. The 7 WTPs that take raw water from streams or springs had a maximum turbidity of less than 50 NTU under heavy rain. However, due to concerns of turbidity spike in treated water, some WTPs discontinued intaking raw water when raw water turbidity increased more than 2 NTU. They instead received treated water from other WTPs which took groundwater for water supply. This happens because of the low skills of employees. Thus, there needs to be an increase in operator competency and upgrade of water facilities for the adaption of heavy rain. To improve adaption for the drought, there should be an increase in the capacity of intake facilities of surface water as well as a decrease in water loss. In addition, water consumption per person should be decreased.

Optimal processes to remove chromaticity at E water treatment plant(WTP) mainly caused by algae of E lake in Jeju island were investigated based on lab-tests of chlorine and ozone oxidation. 42.9% of chromaticity of filtered water was removed by chlorine oxidation under pH 7.0∼8.0, dose of 1.0 mg/L with contact time of 30∼60 min. On the other hand, chromaticity removal was 71.4% when post-ozone dose of 0.9∼1.9 mg/L and pH 9.0, while it was increased to 86.7% under post-ozone dose of 3.1∼7.3 mg/L and pH 9.0. However, there was no significant chromaticity removal efficiency increase when ozone doses were higher than 5.0 mg/L regardless of feeding point(i.e., pre-ozonation and post-ozonation) and pHs(i.e., 7.0 and 9.0.) under the experimental conditions. Based on the results, chlorine oxidation using existing chlorination facilities at the WTP is recommended for lower chromaticity while ozone oxidation is recommended for higher chromaticity by installing new ozone feeding facilities.

In this study, using the synetics technique for strategies by making unfamiliarity into familiarity in the case of 911 terrorism. This study has meaningful messages for citizens and firefighters’ illness caused by disaster sites in the field of disaster management in Korea. There are 7 stages to explain cause of a variety of cancers happening to citizens and firefighters in this study. The 7 stages are composed of real situation, direct analogies, personal analogies, symbolic analogies, new direct analogies, and review. This synetics will contribute to providing better ideas for citizens and firefighters’ physical and mental health conditions.

Jeju Eoseungsaeng lake which is a main water resource of Eoseungsaeng water treatment plant(Q=15,000 m3/d) experienced high chromaticity(40 CU) and pH(9.46) in 2013. This could decline customer's confidence on drinking water quality unless proper identification and removal of chromaticity were implemented. To find cause of chromaticity, water monitoring on various water parameters including TOC, algal cell count, Chl-a, turbidity, SS, conductivity, etc. were implemented. Iron and manganese were excluded from the cause of chromaticity due to its low concentration (i.e., < 0.02 mg/L). Correlation among water parameters showed that relationship between algal cell count and chromaticity was the highest(R=0.43), which suggested that presumably the main reason of chromaticity occurrence in Jeju Eoseungsaeng lake was algae.

Peak load rate(i.e., maximum daily flow/average daily flow) has not been considered for industrial water demand planning in Korea to date, while area unit method based on average daily flow has been applied to decide capacity of industrial water treatment plants(WTPs). Designers of industrial WTPs has assumed that peak load would not exist if operation rate of factories in industrial sites were close to 100%. However, peak load rates were calculated as 1.10~2.53 based on daily water flow from 2009 to 2014 for 9 industrial WTPs which have been operated more than 9 years(9-38 years). Furthermore, average operation rates of 9 industrial WTPs was less than 70% which means current area unit method has tendency to overestimate water demand. Therefore, it is not reasonable to consider peak load for the calculation of water demand under current area unit method application to prevent overestimation. However, for the precise future industrial water demand calculation more precise data gathering for average daily flow and consideration of peak load rate are recommended.

Recently, the need for asset management(AM) plan introduction to reduce increasing O&M cost with aging water facilities is on the rise. Therefore, asset inventory classification is necessary as the first step for AM plan construction. In this study, all assets of YW water treatment plant(WTP) were classified as 5 steps. In addition, specific code name was given to each asset which can increase compatibility in constructing the AM programs among WTPs. In the future, codes for attribute and status of asset will be allocated, which can facilitate proper AM operation.

Pollutants removal efficiency in pretreatment(GAC filter, multi-media filter, disk filter) and RO facilities was investigated for the Jeju Samyang spring water source where raw water intake has been stopped due to sea water intrusion. In addition, preliminary feasibility analysis was conducted between RO and groundwater intake systems. Turbidity removal in 4 different pretreatment processes was less than 25% due to low concentration of turbidity(i.e., less than 0.21 NTU), while multi-media filter is recommended for the pretreatment facility based on the low organic content in raw water as well as cheaper operation and maintenance cost. The average concentration of Cl- in raw water was 691.4 mg/L, while that of RO permeate was 9.1 mg/L(i.e., removal efficiency was 98.4%). In addition, TDS removal efficiency was 98.1%, which was quite high. The production cost for RO system(Q=4,000 m3/d) was 362.1 won/m3 considering installation, operation and maintenance cost for 30 years. While that of groundwater was 262.6 won/m3 which was low compared to the RO system. However, it is recommended to introduce RO system for Samyang water source rather than new groundwater development because Samyang water source has been discharged to the sea without any usage, while groundwater can be used for other purpose as a sustainable water source.

The research purpose is to get implications through case analysis for prediction and response to Mega-complex disaster which have been growing concerned with vulnerabilities of city centered. To do this, we apply synectics model which have been used to analyze for policy agenda from a view point of society and people to 911 terror. In the strategy 「make strange to accustomed」of synectics model, Firstly clarify of case summary include response and results, secondly check direct analogy for responders and media with personal analogy who are qualified to investigation. Findings are different perspective and long term health effects, social indirect cost in comparison with analogies. Proposals of political inferred meaning are unified incident command system, regulation improvement and Research needs for longitudinal health effects evaluation approach to the phase of response to disaster in analysis with final re-search and analogy generalization.

In recent years, the surroundings of Fire have rapidly changed and citizens need for Fire have been demanding very high. Under these situations, in order for satisfaction to all these demands, Seoul Emergency Operations Center have made improvements as the core fire operational center in Korea. However, There have been so many problems happening in the middle of receiving calls from malice citizens of Seoul. The purpose of this study is to scrutinize current operations focused on fire fighters in Seoul Emergency Operations Center and to cope with how to overcome these problem by using AMOS 21 & SPSS Statistics 21. The result of this study presents that how we can find to be Seoul Emergency Operations Center running well. And This study is applied to seoul fire policies or helped to setting them up.

Many advanced treatment processes have been introduced to WTPs, however, the consumer confidence on tap water is still low and the percentage of drinking water directly from the tap is less than 2 %. One of the methods to improve the credibility of tap water is to introduce a drinking water certification system. By introducing the system, water treatment processes can be optimized, which in turn, can significantly improve drinking water quality. In this paper, 6 water quality parameters(i.e., turbidity, CT, residual chlorine, geosmin, 2-MIB, Mn) which have significant influences on tap water quality and consumer confidence were identified, and their recommended guidelines were proposed. 3-Star or 5-Star certification can be awarded to the WTPs which have met the certification criteria. The drinking water certification system can be carried out as a voluntary program among drinking water suppliers.

16 water treatment plants(WTPs) in Jeju province were investigated to evaluate the corrosivity of tap water. In addition, the impacts of lime and carbon dioxide on LI changes at ES WTP were analyzed. The average of LI in Jeju tap was -1.78 which was similar to that of in-land multi-regional WTPs. The recommended process to improve LI of ES WTP which has high corrosivity(i.e., LI = -2.61) was to combine lime and carbon dioxide with the dosages of 20 mg/L and 5 mg/L respectively to meet LI of -1.0 ~ 0. pH was confirmed to be a major water quality parameter that determined LI based on the correlation results among LI and water quality parameters. Precaution on turbidity increase by lime addition should given to minimize particle breakthrough in the distribution system. Turbidity increase can be controlled by the addition of lime prior to filters.

In recent years, the surroundings of Fire have rapidly changed and citizens need for Fire have been demanding very high. Under these situations, in order for satisfaction to all these demands, Seoul Metropolitan Government Fire Academy(SFA) have only to improve its educational training program as the fire educational training center in Korea. The purpose of this study is to scrutinize current educational training program of SFA and measure the relative weight among the hierarchy of disaster management(prevention and mitigation-preparedness-response-recovery) by using the Analytic Hierarchy Process(AHP). The result of this study presents that how many hours must be allocated and set the educational training program with scientific and systematic way of AHP compared the current program of SFA　in 2013. And This study is applied to increase access and comprehension about the AHP and will be able to present guideline for the selection of optimal the educational training of SFA to serve Seoul citizens the best Fire services.

A pilot plant (Q=5 m3/d) study was implemented for small and medium sized personal wastewater treatment plant effluent to evaluate MBR and A/O processes utilizing self-sufficient energy composed of wind and solar energy. The removal efficiencies of BOD, SS, turbidity and color were sufficient for legal water quality standards for gray water. However, those of nitrogen and phosphorus could not meet legal regulations which suggested that further removal of those contaminants were needed for reuse of the treated water.Self-sufficient energy rate was 100 % for the pilot plant due to excessive design capacity. In this research, wind and solar energy system was applied considering geological characteristics, which significantly improved energy self-sufficiency. Substantial improvement on energy self-sufficiency can be obtained by optimized investment and operation at a full scale wastewater treatment plant.

Three water treatment plants(WTPs) in Jeju island whose source water have different characteristics from those of the mainland of Korea were investigated. Coefficients of bulk water decay(kb ) of free chlorine at 5 ଌ for ES, GJ, NW WTPs were -0.003 hr -1, -0.002 hr -1 and −0.001 hr -1 respectively based on bottle tests.To simulate the free chlorine variations in the distribution system using EPANET, ES WTP was chosen. Free chlorine concentrations of several sites were less than the drinking water quality standards(i.e., 0.1 mg/L); E5(0.03 mg/L), E6(0.02 mg/L), W21(0.02 mg/L) and W25(0.03 mg/L). To maintain more than 0.1 mg/L of free chlorine in the distribution system, at least 1.9 mg/L of chlorine was needed at the WTP, which suggested rechlorination was needed to supply palatable tap water to customers.Two sites, one that diverged into E5 and E6 in the east-line and another located before E21 in the west-line were selected for the appropriate rechlorination locations. The recommended rechlorination dosages were 0.42 mg/L for the east and 0.27 mg/L for the west. The simulated results indicated that the free chlorine could be reduced to 0.4 mg/L at the WTP with rechlorination, and taps with excessive free chlorine could be more stabilized(i.e., 0.1 ~0.4 mg/L).