• Journal of Soil and Groundwater Environment
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• v.26 no.4
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• pp.8-19
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• 2021

In this study, the evaluation standard for nitrate nitrogen contamination degree (WELCUP) was established using six factors that influence the groundwater quality in Jeju Island. To do this, weightings, ranges, and ratings were assigned for each factor and the relative possibility of nitrate nitrogen contamination degree was evaluated using WELCUP index for each well. As a result of calculating the WELCUP index using groundwater quality data of 5,112 wells in Jeju Island for 27 years (1993-2019), all 61 wells with the WELCUP index value higher than 100 are distributed in Daejung and Hangyung watershed with relatively large area of farmland in Jeju Island. In particular, as the ratio of private wells is more than 64%, it is necessary that systematic management is needed for private wells in terms of nitrate nitrogen contamination. Consequently, based on the results of applying the WELCUP evaluation standard, it is necessary to select the prioritization of nitrate nitrogen contamination pathways project for groundwater wells in Jeju Island.

• The Journal of Engineering Geology
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• v.23 no.2
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• pp.105-115
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• 2013

Increasing the river cross-section by barrage construction causes rises in the average river water levels and discharge rates in the rainy season. The time series patterns for groundwater levels measured at 23 riverside monitoring wells along the lower Nakdong River are compared for two cases: before and after water-filling at the Changnyeong-Haman Barrage. Monthly average groundwater levels indicate a distinct increase in groundwater levels in the upstream riverside close to the barrage. River-water level management by barrage gate control in August, during the rainy season, resulted in a 0.1 m decrease in groundwater levels, while water-filling at the barrage in December caused a 1.3 m increase in groundwater levels. The results of hierarchical cluster analysis indicate that seven groundwater monitoring wells and river water levels were in the same group before barrage construction, but that this number increased to 14 after barrage construction. Principal component analysis revealed that the explanation power of two principal components corresponding to river fluctuation, PC1 and PC2, was approximately 82% before barrage construction but decreased to 45% after construction. This finding indicates that the effect of the river level component that contributes to change in groundwater level, decreases after barrage construction; consequently, other factors, including groundwater pumping, become more important. Continuous surveying and monitoring is essential for understanding change in the hydrological environment. Water policy that takes groundwater-surface water interaction into consideration should be established for riverside areas.

• Journal of Korea Water Resources Association
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• v.50 no.12
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• pp.815-825
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• 2017

Groundwater management vulnerability was assessed using TOPSIS (Techniques for Order Performance by Similarity to Ideal Solution) for 21 administrative districts in Nakdong river basin. Ten indicators were selected for 21 administrative districts in the Nakdong river basin by collecting natural, human, and social data sets. The selected indicators were standardized using rescale method, and each indicator was weighted by considering the questionnaire of expert group. The results of the weights determination survey showed that the annual average groundwater level index was 0.157 and this is the highest value. The annual average precipitation index was 0.154 and the annual groundwater recharge index was 0.152. The lowest weighted index was 0.043 for population density. Finally, the result of assessment of groundwater management vulnerability showed that Sangju-si was the most vulnerable to groundwater management among 21 administrative districts in Nakdong river basin because the annual average precipitation, annual average groundwater recharge, and annual average groundwater use indicators were highly vulnerable. The second and the third vulnerable regions were Yecheon-gun and Haman-gun respectively. The assessment of groundwater management vulnerability for the five major river basins in Korea can be a essential basis for the establishment of groundwater management policy.

• Journal of Soil and Groundwater Environment
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• v.17 no.2
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• pp.1-6
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• 2012

Total Economic Value (TEV) provides a framework to estimate the economic value of water resources including groundwater with multiple applications to natural resource economics and environmental economics. Crucial to the application of economic analysis to natural resources are techniques to value the resources as an economic value that is expressed in monetary terms. On the other hand, the aim of TEV estimation is to determine the economic value of water resources including 'use' with production and recreation and 'non-use' such as existence values. TEV is used to assess the economic value of water resources for the multiple goods, and environmental 'services' that are provided by a water resource and also used to assess options for water use, for example balancing production values provided by water resource use against the cost of resource degradation by that use. The value of TEV can be assessed over time where pollution or unsustainable use may reduce the economic value of an environmental asset. Therefore, values are used to assess options of resource use, sometimes leading to policies on resource conservation or allocation. In conclusion, the application of TEV would be well adjusted over Jeju Island where groundwater resources account for more than 98% water resources and the budget of water demand/supply shows disparity over the Island.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.37-45
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• 2009

Susceptibility assessment of groundwater contamination is a useful tool for many aspects of regional and local groundwater resources planning and management. It can be used to direct regulatory, monitoring, educational, and policy-making efforts to highly vulnerable areas. In this study, a semi process-based was proposed to evaluate relative susceptibilities to groundwater contamination by nitrate on a regional scale. Numerical simulation based on data from each soil series was done to model water flow within soil profiles that were related to groundwater contamination by nitrate. Relative vulnerability indices for each soil series were produced by manipulation of amount of leaching flux, amount of average water storage in a soil profile, and amount of average water storage change. These indices were designed to convey the trend of leaching flux and to maximize spatial resolution. The resulting vulnerability distribution map was used to locate highly vulnerable sites easily with an appropriate grouping the indices, and was then compared with those from groundwater nitrate concentrations monitored. An excellent agreement was obtained across nitrate concentrations from the highly vulnerable regions and those from the low to stable regions.

• Journal of Environmental Policy
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• v.9 no.2
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• pp.157-184
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• 2010

Global climate change is destroying the water circulation balance by changing rates of precipitation, recharge and discharge, and evapotranspiration. The Intergovernmental Panel on Climate Change (IPCC 2007) makes "changes in rainfall pattern due to climate system changes and consequent shortage of available water resource" a high priority as the weakest part among the effects of human environment caused by future climate changes. Groundwater, which occupies a considerable portion of the world's water resources, is related to climate change via surface water such as rivers, lakes, and marshes, and "direct" interactions, being indirectly affected through recharge. Therefore, in order to quantify the effects of climate change on groundwater resources, it is necessary to not only predict the main variables of climate change but to also accurately predict the underground rainfall recharge quantity. In this paper, the authors selected a relevant climate change scenario, In this context, the authors selected A1B from the Special Report on Emission Scenario (SRES) which is distributed at Korea Meteorological Administration. By using data on temperature, rainfall, soil, and land use, the groundwater recharge rate for the research area was estimated by period and embodied as geographic information system (GIS). In order to calculate the groundwater recharge quantity, Visual HELP3 was used as main model for groundwater recharge, and the physical properties of weather, temperature, and soil layers were used as main input data. General changes to water circulation due to climate change have already been predicted. In order to systematically solve problems associated with how the groundwater resource circulation system should be reflected in future policies pertaining to groundwater resources, it may be urgent to recalculate the groundwater recharge quantity and consequent quantity for using via prediction of climate change in Korea in the future and then reflection of the results. The space-time calculation of changes to the groundwater recharge quantity in the study area may serve as a foundation to present additional measures for the improved management of domestic groundwater resources.

• Journal of Environmental Policy
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• v.4 no.2
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• pp.57-82
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• 2005

In this study, we propose methods for. the efficient management and integrity of groundwater in response to a diminishing supply. As an alternative water resource for the future. we investigated and comparatively analyzed the quality standards of groundwater in the US (New York, Wisconsin and Texas), Austria, Netherlands, Canada, Japan and United Kingdom. These developed countries heavily depend on groundwater, more than 70%, for drinking water and apply those drinking water standards to groundwater quality. However, there exists few differences in the quality standards of groundwater among the countries, because each country possesses its own individual environment and management. In Korea, surface water pollution is getting serious and its water resources are diminishing. Therefore we propose several new quality criteria that many countries regulate at these days for their efficient management of groundwater. There is a need to divide BTEX criterion into Benzene, Toluene, Ethylbenzene and Xylene, individually. In. addition, it is needed to establish BTEX criteria into agricultural water and industrial water use standards as well as daily life use standards. Also, regulations for some PAHs, showing carcinogenicity, are required. Due to rapid industrialization various hazardous chemicals were utilized and their uses are increasing each year. Therefore, there is a strong need to introduce n~w standards and tighter regulations of the levels. At the same time, the criterion of nitrogenous compounds need' to be regulated individually in order to prevent the damage incurred by the compounds. Several developed countries have established standards for radon, previously caused environmental accidents in Korea. Therefore, we propose the necessity of groundwater quality standards for radon in this study.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.36-46
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• 2021

The Soil Health Index (SHI) developed by Park et al. (2021) is used to evaluate soil health on remediated soils collected from several remediation project sites and monitored the changes of SHI during the remediation process of land farming, soil washing, and thermal desorption. In the case of land farming, the soils remediated below a legal standard didn't show any significant changes in indices of SHI except the downgrade of available phosphate from medium to a low level. The SHI scores were ranged from 52 to 56 in the contaminated soil and 54 to 57 in the remediated soil. With soil washing, bulk density changed from high to a low level, and available phosphate was lowered from medium to low level. As the SHI scores were evaluated as 58 to 63 for contaminated soil and 38 to 42 for remediated soils. For thermal desorption, soil respiration rate was reduced from high to low level and SHI was scored as 50 to 51 for contaminated soils and 43 to 47 for remediated soils. Even though any abrupt changes of the SHI in remediated soils were not identified in the soils used in this study, it is expected that soil in different conditions such as types and concentrations of contaminant and soil characteristics would result in distinguished changes of the SHI. There is a room for more studies collect diverse information on SHI across the country.

• Journal of Soil and Groundwater Environment
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• v.21 no.6
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• pp.156-168
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• 2016

The Korean government is planning to invest a lot of funds for conservation of the soil. Accordingly, it needs quantitative information on the soil. This paper attempts to analyze the total value of soil quantitatively: the total economic value of soil can be divided into use value and non-use value. To this end, we apply a replacement cost method (RCM) and contingent valuation method (CVM). Especially, CVM is most widely used to measure the non-use value such as environment goods. We employed the one-and-one-half-bounded dichotomous choice (OOHBDC) for willingness to pay (WTP) elicitation and a spike model. The monthly mean WTP was estimated to be KRW 3,949 per household for the next 10 years, which is statistically significant at the 1% level. Expanding the value to the relevant population gives us KRW 897.9 billion per year and as of the end of 2015, the non-use value of soil was assessed to be KRW 838.6 billion. Meanwhile, use value is subdivided into direct use value and indirect use value. This value was calculated KRW 3,277 trillion and KRW 51.8 trillion, respectively. As a result, total economic value of soil is estimated to be KRW 3,330 trillion in Korea.

• Journal of Soil and Groundwater Environment
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• v.10 no.3
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• pp.52-63
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• 2005

Korea has recently implemented two m메or policies on organic wastes, including food wastes. One is the Volume-Based waste Fee System (VBWFS). which went effect nationwide in January 1995, and the other is a ban on the landfill of organic wastes, such as food wastes. organic sludge, and animal manure, in accordance with the Waste Management Act. These two policies have brought about remarkable positive effects, including the reduction of organic wastes at source, and the development of technology for recycling food wastes into feed and compost. However, they have caused obstacles to carry out the policy on food wastes, in areas of legal and technological infrastructures for recycling. Therefore, this study intends to find problems of policies for recycling food wastes, and to suggest ways to resolve them.