• Journal of Environmental Policy
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• v.8 no.1
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• pp.129-143
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• 2009

In South Korea, Mine industries were encouraged to obtain the natural resource from 1960 to 1980. However, the depletion of natural resource and decreasing price have been caused by the voluntary closure of non-economical mines and a cut of their production since 1990. Harmful wastewater containing such heavy metals as iron, aluminum, arsenic, and cadmium are being discharged from abandoned pits and waste stone and tailing dumping sites following the closure of mines. Therefore, the objective of this paper suggests a policy of mine hazard prevention(PMHP) and method that allows the combination of new spatial data and as well as collected data on resources for the sustainable mine reclamation and management using EGIS/MGIS technique to develop an integrated plan and management techniques.

• Journal of Environmental Science International
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• v.15 no.10
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• pp.919-928
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• 2006

The present study applied an atmospheric flow field model in Gwangyang-Bay which can predict local sea/land breezes formed in a complex terrain lot the development of a model that can predict short term concentration of air pollution. Estimated values from the conduct of the atmospheric flow field were used to evaluate and compare with observation data of the meteorological stations in Yeosu and the Yeosu airport, and the effect of micrometeorology of surround region by the coastal area reclamation was predicted by using the estimated values, Simulation results, a nighttime is appeared plainly land breezes of the Gwangyang-bay direction according to a mountain wind that formed in the Mt. of Baekwooun, Mt. of Youngchui. Land winds is formed clockwise circulation in the north, clockwise reverse direction in the south with Gangyang-bay as the center. Compared with model and observation value, Temperature is tend to appeared some highly simulation value in the night, observation value in the daytime in two sites all, but it is veil accorded generally, the pattern of one period can know very the similarity. And also, wind speed and wind direction is some appeared the error of observation value and calculation results in crossing time of the land wind and sea land, it can see that reproducibility is generally good, is very appeared the change land wind in the nighttime, the change of sea wind in the daytime. And also, according to change of the utilization coefficient of soil before and after development with Gwangyang-Bay area as the center. Temperature after development was high $0.55\sim0.67^{\circ}C$ in the 14 hoots, also was tend to appear lowly $0.10\sim0.22^{\circ}C$ in the 02 hours, the change of u, v component is comparatively tend to reduced sea wind and land wind, it is affected ascending air current and frictional power of the earth surface according to inequality heating of the generation of earth surface.

• Geomechanics and Engineering
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• v.10 no.5
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• pp.677-687
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• 2016

Industrialization and urbanization are the two phenomena that are going relentless all over the world. The consequence of this economic success has been a massive increase in waste on one hand and increasing demand for suitable sites for construction on the other. Owing to the surplus raw materials and energy requirement needed for manufacturing synthetic fibers, applications of waste fibers for reinforcing soils evidenced to offer economic and environmental benefits. The main objective of the proposed work is to explore the possibilities of improving the strength of soil using fly ash waste as an admixture and Human Hair Fiber (HHF) as reinforcement such that they can be used for construction of embankments and land reclamation projects. The effect of fiber content on soil - fly ash mixture was observed through a series of laboratory tests such as compaction tests, CBR and unconfined compression tests. From the stress - strain curves, it was observed that the UCC strength for the optimised soil - flyash mixture reinforced with 0.75% human hair fibers is nearly 2.85 times higher than that of the untreated soil. Further, it has been noticed that there is about 7.73 times increase in CBR for the reinforced soil compared to untreated soil. This drastic increase in strength may be due to the fact that HHF offer more pull-out resistance which makes the fibers act like a bridge to prevent further cracking and thereby it improves the toughness which in turn prevent the brittle failure of soil-flyash specimen. Hence, the test results reveal that the inclusion of randomly distributed HHF in soil significantly improves the engineering properties of soil and can be effectively utilized in pavements. SEM analysis explained the change of microstructures and the formation of hydration products that offered increase in strength and it was found to be in accordance with strength tests.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.262-270
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• 2015

The scientific information between microbial community and chemical properties of reclaimed tidal soil is not enough to understand the land reclamation process. This study was conducted to investigate the relation between chemical properties and microbial activities of soils from reclaimed tidal lands located at south-western coastal area (42 samples from Goheuong, Samsan, Bojun, Kunnae, Hwaong and Yeongsangang sites). Most of the reclaimed soils showed chemical characteristics as salinity soil based on EC. Only $Na^+$ in exchangeable cation was dependent on EC of reclaimed soil, whereas other cations such as $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were independent on EC. The mesophilic bacteria decreased with an increase in EC of soil. Microbial population increased with soil organic content in the range of $0{\sim}10g\;kg^{-1}$ and dehydrogenase activity less than $100{\mu}g-TPF\;g^{-1}h^{-1}$. Microbial population of soils from reclaimed tidal lands was closely related to the microbial community containing hydrolytic enzyme activities of cellulase, amylase, protease, and lipase.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.229-235
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• 2021

To dispose of waste, there are methods such as landfill, incineration, recycling, and sea discharge. Since the landfill wastes accumulate, there is a limit to the landfill site to accommodate them. In this paper, a time series analysis and current status of landfill allowance was analyzed over 20 years of landfills distributed throughout the country using GIS to understand the status of waste reclamation. As a result, the emissions of waste were gradually increasing, and as the emissions increased, the amount of landfill increased. The landfills in the Seoul metropolitan area have been saturated and need to be resolved as soon as possible.

• Journal of the Korean GEO-environmental Society
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• v.12 no.6
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• pp.43-51
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• 2011

Marine clays are widely distributed in Korean eastern, western and southern coastal areas. Understanding engineering characteristics of the soft ground is very important, whenever civil structures are constructed in those coastal areas. It is because the ground is composed of highly compressible marine clay. In this paper, the physical and compression characteristics of Incheon, Mokpo, Gwangyang and Busan marine clay were analyzed and the characteristics between western and southern coastal marine clays were compared. For this, test results of 1,471 samples from 114 sites were used. As a result, Incheon clay showed the lowest plasticity and the highest unit weight due to influx of silt from the Yellow River and the turn of the tide of Incheon area. However, Gwangyang clay showed highly compressible characteristic due to extensive reclamation. On the other hand, Mokpo and Busan clay showed partially similar levels of characteristics. The compression index of Mokpo and Busan clay was high more than twice in comparison with Incheon clay and that of Gwangyang clay was higher than seventy percents in comparison with Mokpo and Busan clay.

• Advances in nano research
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• v.12 no.6
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• pp.549-566
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• 2022

Mining of ore minerals (sfalerite, cinnabar, and chalcopyrite) from the old mine has led in significant environmental effects as contamination of soils and plants and acidification of water. Also, nanoparticles (NP) have obtained global importance because of their widespread usage in daily life, unique properties, and rapid development in the field of nanotechnology. Regarding their usage in various fields, it is suggested that soil is the final environmental sink for NPs. Nanoparticles with excessive reactivity and deliverability may be carried out as amendments to enhance soil quality, mitigate soil contaminations, make certain secure land-software of the traditional change substances and enhance soil erosion control. Meanwhile, there's no record on the usage of Nano superior substances for mine soil reclamation. In this study, five soil specimens have been tested at 4 sites inside the region of mine (<100 m) to study zeolites, and iron sulfide nanoparticles. Also, through using Artificial Neural Network (ANN) and Extreme Learning Machine (ELM), this study has tried to appropriately estimate the mechanical properties of soil under the effect of these Nano particles. Considering the RMSE and R2 values, Zeolite Nano materials could enhance the mine soil fine through increasing the clay-silt fractions, increasing the water holding capacity, removing toxins and improving nutrient levels. Also, adding iron sulfide minerals to the soils would possibly exacerbate the soil acidity problems at a mining site.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.411-418
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• 2013

The Saemangeum Reservoir was constructed in 2006 as a part of Saemangeum reclamation project in which desalination has been also carried out. The purpose of this study is to provide basic data for predicting changes in fish distribution in the Saemangeum area with respect to the desalination processand to identify current status of fish distribution along with salinity levels. Fish sampling and measurement of salinity were conducted 4 times from February to October in 2012 at 10 sites within the Saemangeum Reservoir. A total of 71 species classified into 34 families were confirmed, and dominant and subdominant species were Thryssa kammalensis (16.1%) and Konosirus punctatus (12.8%), respectively. Saltwater fishes were still dominant at the Saemangeum Reservoir. Study sites were classified into four groups (A=St. 1, 6; B=St. 2, 3, 7, 8; C=St. 4, 9, 10; D=St. 5) by Bray-Curtis cluster analysis. Species composition of each group was closely related with salinity level: group A corresponding to 0.2 psu, B to 14.2 psu, C to 19.5 psu, and D to 23.5 psu.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.5-12
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• 2019

The study is carried out to survey the proper management and to propose an eco - friendly separation system through efficient screening and resource recovery of excavated materials containing waste from various excavating fields such as reconstruction of landfill sites for reuse, reclamation of unsanitary landfill and residential land development of waste dumping sites. The current status and screening process and analytical characteristics of the excavated materials containing waste were reviewed. Through the analysis of the samples such as separated combustibles, recyclable soils and residues collected from the on-site visits we were able to understand the characteristics of separated materials and excavated materials containing waste such as calorific value, elementary composition, TOC, foreign material content and LOI. It has been found that elimination of the moisture of excavations, removal of attached soil from the surfaces of the excavated combustibles and the quantitative supply method of the input devices are the main operating factors as essential factors for the optimal separation of excavated materials containing waste. For efficient management and recycling of excavated materials containing, it is necessary to set criteria of ash content in separated combustibles and criteria organic matter content in separated soils.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.335-345
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• 2005

A study on changes on the distribution of vascular hydrophytes and the growth pattern of Schenoplectus triqueter (Scirpus triqueter) was undertaken at the Nakdong River estuary from 2002 to 2004. The change was due to physical alteration of the estuary for the past 25 years. These plant species are the major food sources for winter waterfowl. A total of 32 species of vascular hydrophytes from 17 families were found in the West Nakdong River (freshwater), the main channel of Nakdong River (freshwater) and the Nakdong River Estuary (brackish water). After the construction of the barrage on the estuary in 1987, the number of hydrophytes has remarkably increased to 17 species (5 species in 1985) in the main channel of the River. In particular, a community of Eurale ferox was found at the backwater wetland of the Daejeo side of the main channel. The introduced species of Eichhornia crassipes and Pistia stratiotes that were epidemic in 2001 at West Nakdong River was not found any more. The other species such as Nymphoides indica, Myriophyllum spicatum, Ruppia spp. were rediscovered. The large area (about 1,300ha) of Zostera spp. was the main sources of food for swans, but disappeared because of direct and indirect impacts of reclamation in the River estuary. Currently, there remains a small patch of Zostera spp. and about 250ha of S. triqueter. Schenoplectus triqueter grew mostly between April-September and tuber formed, between September-October. The growth of S. triqueter up to $60\sim80cm$ in length was observed in 5 sites out of the 7 sites in brackish area. Tubers of S. triqueter were eaten by waterfowls such as swans as winter food. In five sites, tubers took $44\sim57%$ of total biomass in October. Tubers were found in deep layers; $5\sim15cm$ (9%), $15\sim25cm$ (28%), $25\sim40cm$ (55%), below 40cm $(6\sim7%)$. The distribution of vascular hydrophytes has remarkably changed in the Nakdong River Estuary due to the reclamation of the area. In order to determine the extent of changes of the distribution of these plants and the carrying capacity of the area for waterfowl, an intensive research is urgently needed.