• Journal of Korea Water Resources Association
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• v.55 no.12
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• pp.999-1009
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• 2022

The Chuncheon Mullori area is an underprivileged area for water welfare that does not have a local water supply system. Here, water is supplied to the village by using a small-scale water supply facility that uses underground water and underground water as the source. To solve the problem of water shortage during drought and to prepare for the increasing water demand, a sand dam was installed near the valley river, and this facility has been operating since May 2022. In this study, in order to evaluate the reliability of water supply when a sand dam is assumed during a drought in the past, groundwater runoff simulation results using MODFLOW were used to generate inflow data from 2011 to 2020, an unmeasured period. After performing SWAT-K basin hydrologic modeling for the watershed upstream of the existing water intake source and the sand dam, the groundwater runoff was calculated, and the relative ratio of the monthly groundwater runoff for the previous 10 years to the monthly groundwater runoff in 2021 was obtained. By applying this ratio to the 2021 inflow time series data, historical inflow data from 2011 to 2020 were generated. As a result of analyzing the availability of water supply during extreme drought in the past for three cases of demand 20 m³/day, 50 m³/day, and 100 m³/day, it can be confirmed that the reliability of water supply increases with the installation of sand dams. In the case of 100 m³/day, it was analyzed that the reliability exceeded 90% only when the existing water intake source and the sand dam were operated in conjunction. All three operating conditions were evaluated to satisfy 50 m³/day or more of demand based on 95% reliability of water supply and 30 m³/day or more of demand based on 99% of reliability.

• Journal of Soil and Groundwater Environment
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• v.14 no.4
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• pp.33-44
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• 2009

Water curtain of an underground LPG storage cavern is a facility to prevent leakage of high pressure gases, for which groundwater should flow freely towards the cavern and groundwater level also must be stably maintained. In this study, in order to evaluate qualities of seepage water and surrounding groundwater of an underground LPG storage cavern in Yeosu, 4 rounds of samplings, field measurements and laboratory analyses (February, May, August, October of 2007) were conducted. According to field measurements, pH was weak acidic to neutral but it gradually increased with time. Electrical conductivity (EC) of groundwater near a salt stack showed very high values between 10.47 and 38.50 mS/cm. Dissolved oxygen (DO) showed a very wide range of 0.20~8.74 mg/L and a mean of oxidation-reduction potential (ORP) was 159 mV, which indicated an oxidized condition. Levels of $Fe^{2+}$ and $Mn^{2+}$ were mostly less than 3 mg/L. All of seepage waters showed a Na-Cl type while only groundwater near the salt stack showed a Na-Cl type with a high total dissolved solid. The other groundwaters exhibited typical $Ca-HCO_3$ types. Levels of aerobic bacteria were mostly very high (573-39,520 CFU/mL). Based on the analyses of these hydrochemistry and biological characteristics, it is concluded that there are no particular problems in groundwater and seepage water, which not causing a trouble in the cavern operation. However, both for control of bio-clogging and for sustainable operation of the water curtain system, a regular hydrochemical and microbiological monitoring is required for the seepage water and surrounding groundwater.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.167-175
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• 2019

To effectively deal with the fire in tunnel which is mostly the vehicle fire, it's more important to suppress the fire at early stage. In urban tunnel, however, accessibility to the scene of fire by the fire fighter is very limited due to severe traffic congestion which causes the difficulty with firefighting activity in timely manner and such a problem would be further worsened in underground road (double-deck tunnel) which has been increasingly extended and deepened. In preparation for the disaster in Korea, the range of life safety facilities for installation is defined based on category of the extension and fire protection referring to risk hazard index which is determined depending on tunnel length and conditions, and particularly to directly deal with the tunnel fire, fire extinguisher, indoor hydrant and sprinkler are designated as the mandatory facilities depending on category. But such fire extinguishing installations are found inappropriate functionally and technically and thus the measure to improve the system needs to be taken. Particularly in a double-deck tunnel which accommodates the traffic in both directions within a single tunnel of which section is divided by intermediate slab, the facility or the system which functions more rapidly and effectively is more than important. This study, thus, is intended to supplement the problems with existing tunnel life safety system (fire extinguishing) and develop the remote-controlled automatic fire extinguishing system which is optimized for a double-deck tunnel. Consequently, the system considering low floor height and extended length as well as indoor hydrant for a wide range of use have been developed together with the performance verification and the process for commercialization before applying to the tunnel is underway now.

• Asian Journal of Atmospheric Environment
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• v.8 no.1
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• pp.35-47
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• 2014

The purpose of the study is to evaluate the pollution level (gaseous and particle phase) in the public facilities for the PAHs, non-regulated materials, forecast the risk level by the health risk assessment (HRA) and propose the guideline level. PAH assessments through sampling of particulate matter of diameter < 2.5 ${\mu}m$ ($PM_{2.5}$). The user and worker exposure scenario for the PAHs consists of 24-hour exposure scenario (WIES) assuming the worst case and the normal exposure scenario (MIES) based on the survey. This study investigated 20 PAH substances selected out of 32 substances known to be carcinogenic or potentially carcinogenic. The risk assessment applies major toxic equivalency factor (TEF) proposed from existing studies and estaimates individual Excess Cancer Risk (ECR). The study assesses the fine dusts ($PM_{2.5}$) and the exposure levels of the gaseous and particle PAH materials for 6 spots in each 8 facility, e.g. underground subway stations, child-care facilities, elderly care facilities, super market, indoor parking lot, terminal waiting room, internet caf$\acute{e}$ (PC-rooms), movie theater. For internet caf$\acute{e}$ (PC-rooms) in particular, that marks the highest $PM_{2.5}$ concentration and the average concentration of 10 spots (2 spots for each cafe) is 73.3 ${\mu}g/m^3$ (range: 6.8-185.2 ${\mu}g/m^3$). The high level of $PM_{2.5}$ seen in internet cafes was likely due to indoor smoking in most cases. For the gaseous PAHs, the detection frequency for 4-5 rings shows high and the elements with 6 rings shows low frequency. For the particle PAHs, the detection frequency for 2-3 rings shows low and the elements with 6 rings show high frequency. As a result, it is investigated that the most important PAHs are the naphthalene, acenaphthene and phenanthrene from the study of Kim et al. (2013) and this annual study. The health risk assessment demonstrates that each facility shows the level of $10^{-6}-10^{-4}$. Considering standards and local source of pollution levels, it is judged that the management standard of the benzo (a)pyrene, one of the PAHs, shall be managed with the range of 0.5-1.2 $ng/m^3$. Smoking and ventilation were considered as the most important PAHs exposure associated with public facility $PM_{2.5}$. This study only estimated for inhalation health risk of PAHs and focused on the associated cancer risk, while multiple measurements would be necessary for public health and policy.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.4
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• pp.58-69
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• 2018

The purpose of this study was to present specific standards for landscape planning and construction applicable to landscaping areas in various historical sites. The results are as follows: First, the types of historical sites are classified according to their preservation status and processing techniques, and the classification according to their status is divided into those that have been buried underground, such as those that have been exposed to the ground, such as buildings and structures, and those that have a reputation or a record of the sites. The classification according to the wartime processing technique was classified by such techniques as closures that isolate the site, penetration that can be seen on the site, and overlays where a separate protection facility is installed on the site. Second, the principles of landscape planning for display of historical sites are divided into the items that make up the historical site, surface treatment of the sites, tree planting, and installation of facilities. If the site is not a circular space, the area separating the space by different materials between the components is required. In the event that preservation of the historical site is required, it is deemed desirable to use the soil, and to do so, the use of grasses and shrubs is effectively considered to be effective. The introduction of plants and plants should be considered according to the nature of the space. Depending on the area and nature of the monument, the facility is required to take a cautious approach by reviewing its influence on the landscape and the additional excavation of the monument. Third, the readjustment method derived as a result of looking at the landscaping principle in the historical site space was classified as conservation of status, installation of protection facilities, burial, restoration, relocation, and reproduction. Preservation of the status quo is essential for limited landscape planning and should not affect the prototype of existing relics. The protection facility shall be installed where necessary to protect the relics, and when the soil is formed, the surface treatment shall be required to remove trees that could damage the site and prevent soil and soil oil from being lost after the site. The restoration shall establish a landscaping plan according to the circular preservation based on the clues to the circle. The transfer requires a landscaping plan to create an environment similar to the outer space of an existing site and should be able to highlight the value or location of the original site. The reenactment should have a landscaping plan to revive the landscape and atmosphere of the past for the now-defunct remains. Fourth, landscaping can simultaneously satisfy the preservation of excavation sites and the increase in exhibition effects. In order to protect the traces of the past and vitalize the site of the ruins today, specific measures are required, the creation of a park for historical sites that preserve the functions and value of the relics, and the formation of a shape of linked contents can be suggested as alternatives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.365-372
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• 2004

The purpose of this study was to implement HACCP system to foodservice of W and D elementary schools with joint-lunch management system in Kyungsan area. Steamed rice with squid was selected and Control Action, Monitoring Procedure and Control measure were identified based on HACCP flowchart to produce safe and healthy food. It was suggested that frozen squid must be thawed under the cold running city water and kept temperature below 1$0^{\circ}C$ and receiving/thawing procedure has to be done within 30 min. Raw vegetables must be washed under three-tube wash stand and whole prepreparation procedures should be done in 20 minutes. Clean and sanitize all the equipment and utensils before and after handling squid. Knives and cutting boards for vegetable and squid should be classified. Sauce for steamed rice with squid should be heated about 21 minutes to reach the temperature of 94$^{\circ}C$ before serving and internal temperature of food must be kept above 84.4$^{\circ}C$ during serving. The ideal temperature of kitchen should be remained 15∼18$^{\circ}C$. The underground water has to be excluded to minimize the risk of contamination in the foodservice facility and the prepreparation place must be separated with cooking place. Also, Personal hygiene Practice should be check in each stage. Further, additional research needs to be conducted to determine models for HACCP implementation for different menu.

• Journal of Environmental Health Sciences
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• v.44 no.3
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• pp.267-274
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• 2018

Objectives: This study examined the impact of a smoke-free policy on indoor air quality at indoor recreation facilities by assessing $PM_{2.5}$ concentrations before and after the implementation of the new policy. Methods: Using real-time monitors, $PM_{2.5}$ concentrations were measured in 50 billiard rooms and 50 golf simulator rooms in Seoul, Korea. The characteristics of the indoor recreation facilities, smoking status, and atmospheric conditions were recorded at the same time.After the enforcement of a smoke-free policy, $PM_{2.5}$ concentrations, installation of smoking room, and smoking status were examined when the facilities were revisited. Results: Almost a half of the billiard rooms and over 80% of golf simulator rooms were located underground. Seventy percent of the billiard rooms and one hundred percent of the golf simulator rooms were equipped with a local exhaust ventilation system. After the implementation of the smoke-free policy, 46% of the billiard rooms and 20% of the golf simulator rooms newly installed a smoking room. In the billiard rooms with a newly-installed smoking room, the $PM_{2.5}$ concentrations decreased from 97.9 to $45.6{\mu}g/m^3$ after the implementation of the smoke-free policy. The same change of 29.0 to $ 26.3{\mu}g/m^3$ was not statistically significant in golf simulator rooms. Indoor $PM_{2.5}$ concentrations were correlated with outdoor $PM_{2.5}$ concentrations, number of smokers, and number of people in the room. Conclusions: The smoke-free policy for indoor recreation facilities was not effective at making the indoor spaces free from second hand smoke. Although a few billiard rooms installed a smoking room, indoor $PM_{2.5}$ concentrations were still higher than those of outdoor $PM_{2.5}$ or atmospheric $PM_{2.5}$. Stricter enforcement of the smoke-free policy should be achieved to prevent secondhand smoke exposure.

• Korean Journal of Construction Engineering and Management
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• v.10 no.4
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• pp.111-118
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• 2009

This study is to analyze the performance of SWH(Solar Water Heating) and GSHP(Ground Source Heat Pump) systems by evaluating their energy efficiency and LCC(Life Cycle Cost) as being applied to the OO hall as a selected building in the Army. The OO hall, used as bathrooms, dining rooms, accommodations and offices, has reinforced concrete structure system with three floors above the ground and one underground, and its total floor area is approximately 2,917$m^2$. Two energy simulations are conducted to predict the yearly cooling and heating energy of the selected building: One is for analysis of an air-conditioning energy consumption using the e-Quest program, and another is for two new-renewable energy facilities as a water heating source using the RETScreen. The installed capacity of two new-renewable energy facilities is determined according to the 5% level of total standard construction cost. As a briefly result, SWH system is more energy-effective than GSHP system. Considering the break-even point, it is expected that SWH can take only 3 years 11 months to pay for itself in savings while the investment of GSHP can be recovered in more than 16 years 6 months.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.662-671
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• 2020

The uplift force acts directly on the foundation and causes a building to float to the upper ground. To examine the stability of a structure according to the uplift force, four sites (Paju, Anyang, Osan, and Gangneung) were selected, and sensors were installed on the foundations for the field tests. The rainfall characteristics were analyzed around June~September, and the changes in the water level of the adjacent river were considered. The maximum uplift force except for Gangneung did not exceed 72% of the water pressure when the groundwater level was up to the surface. On the other hand, the maximum uplift force in Osan was approximately 67%, but the reliability was slightly inferior because the difference from the average (46%) was large. The minimum uplift force was within 10% except for Anyang (~ 41%). At the Gangneung site on soft rock where the permanent drainage facility was installed before the measurement, the maximum and minimum uplift force was approximately 14% and 3.5%, respectively. Based on the measurement results, the possibility of overdesigning or underdesigning comes from the design by the hydrostatic pressure when the groundwater level is up to the surface.

• Tunnel and Underground Space
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• v.12 no.1
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• pp.52-69
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• 2002

The WIPP (Waste Isolation Pilot Plant), located 42km east of Carlsbad, New Mexico (NM), in bedded salt 655m below the surface, is a mined repository constructed by the US DOE for the permanent disposal of transuranic (TRU) wastes generated by activities related to defence of the US since 1970. Its historical disposal operation began in March 1999 following receipt of a final permit from the State of NM after a positive certification decision for the WIPP was issued by the EPA in 1998, as the first licensed facility in the US for the deep geologic disposal of radioactive wastes. The CCA (Compliance Certification Application) for the WIPP that the DOE submitted to the EPA in 1966 was supported by an extensive performance assessment (PA) carried out by Sandia National Laboratories (SNL), with so-called 1996 PA. Even though such PA methodologies could be greatly different from the way we consider for HLW disposal in Korea largely due to quite different geologic formations in which repository are likely to be located, a review on lots of works done through the WIPP PA studies could be the most important lessons that we can learn from in view of current situation in Korea where an initial phase of conceptual studies on HLW disposal has been just started. The objective of this art report is an overview of the methodology used in the recent WIPP PA to support the US DOE WIPP CCA and some relevant results completed by SNL.