• Journal of Environmental Impact Assessment
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• v.14 no.6
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• pp.365-375
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• 2005

For managing and utilizing a closed municipal solid waste landfill site in environmentally secure conditions, it is necessary to verify the stabilization level of landfill gas(LFG) and waste. For assessing LFG and waste stabilization of an open-dumping municipal solid waste landfill (Salmi Landfill) which is located at the vicinity of Chungju Reservoir which flows into Paldang Reservoir that has been used for Seoul Metropolitan water supplies, the history and the surrounding characteristics of the landfill site were surveyed. In this study, waste and LFG samples obtained from landfill site were physically and chemically analyzed, and then the analysis results were evaluated on the basis of 'The Criteria of Landfill Waste Stabilization(CLWS)' that were promulgated by Korean Ministry of Environment. Based on LFG composition of Salmi landfill, $CH_4$ was as high as 68%. In CLWS regulation, the stabilization criteria of $CH_4$ should be lower than 5%, and the criteria of C/N ratio should also be lower than 1/10. The result showed that C/N ratio of landfilled waste ranged 17.4~24.7. From this results, it was concluded that the LFG and C/N ratio stabilization level of this landfill based on the CLWS were still actively proceeding.

• Journal of the Korean GEO-environmental Society
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• v.6 no.4
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• pp.27-35
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• 2005

A case study of the assessment for environmental stabilization in open dumping landfill site was carried out physical composition, total solid, moisture, and landfill gas(LFG) analysis in landfill site. The result of physical ratio were represented combustibles 23.64% and incombustibles 76.36%, TS 77.69%, VS 74.24%, FS 25.75%. The biodegradable organic matters were almost degraded and the result of the landfill gas showed that the $CH_4$ gas were measured as 4.5%. As the result of the assessment on the open dumping landfill it appears that this landfill is stabled for the maturation phase and formation $CO_2$ concentration lower than 15%.

• Journal of Environmental Impact Assessment
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• v.5 no.2
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• pp.21-31
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• 1996

To assess the impact resulted from the slag dumping, we studied that the changes in the concentration of heavy metal were researched through the statistic analysis at 4 stations in Yongil bay, Korea from 1988 to 1995. And in order to clarify resulting from the changes in heavy metal concentration due to be leaked out from dumped slag, it was fulfilled experiments of the slag extraction. In the extracting experiment, Pb and As were only leaked out from slag aged during 10 days but all of heavy metals were not from it aged during 90 or 180 days. It was found that the concentrations of heavy metals in sea water of vincinity of slag dumping area were still remained in similar, comparing with it of control site(site 4) when they were by analysed statistic method, anova test and Mann-Whitney test. The slag recycling ratio of our country is lower than foreign country. While we need to apply a new process for phosphate treatment, foreign country already apply a slag to phosphorous removal. We suggest that slag dumping cannot putatively affected the changes in the concentration of heavy metal. And we thought that impact of heavy metal induced by slag dumping was not severe. So, it is necessary to utilize this process in phosphorous removal, like a foreign country.

• Ocean and Polar Research
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• v.29 no.3
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• pp.217-231
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• 2007

To explore limiting factors of spring bloom caused by waste disposal after dumping activity commenced in the Yellow Sea, we used a 1-dimensional temperature-ecological coupled model. The vertical structure of temperature and vertical diffusivity (Kh) are calculated by the temperature model with sea surface temperature using the 2.5 layers turbulence closure scheme. The ecological model applied results at the temperature model consisted of five state variables (DIN, DIP, phytoplankton, zooplankton, and detritus) forced by photosynthetically available radiation. We simulate year-to-year variations of plankton and nutrients using the coupled model from 1998 to 2000 and compare results of the model with observed data. It turned out that temperature is the growth factor of spring bloom in dumping area. During the winter the weak stratification made sufficient supply of the accumulated nutrients from the sea bed into the upper water column and led to the bloom in the coming spring. Radiation also turned out to be another important factor of spring bloom in the study area. Insufficient radiation of March 1999 showed low chlorophyll-a concentration despite sufficient nutrients in the surface.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.433-438
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• 2006

When we consider to develop a new harbor, the most important factor, we think, is the lowest water depth of waterway and approaching channel for safe navigation of vesse. The existing harbors have been being dredged to meet the international trend of jumbo sized vessels by adopting the new design criteria. As the dredged materials over the expected at the design level were common and there are still lack of land based reclamation area, we have no choice to discharge the dredged materials in open sea area. In this study, we analysed the behavior of discharged materials at the dumping area of offshore open sea, which were collected from the dredging work at the waterway in Busan New Port. We measured the tidal currents and analyzed the waters of dumping site after the dumping work. these were used to evaluate the numerical models. Suspended Solids(SS) were introduced to the diffusion model. Because of the characteristics of the dumping site, the speed of initial diffusion and settle down of the discharged materials was so fast. Therefore, we believe that the dumped materials do not cause a significant impact to the marine environment.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.2
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• pp.75-81
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• 2004

A large amount 2.1×106 ㎥ of the polluted sediment was dredged from the Masan Bay and deposited in Gapo confined area, Masan. The dissolved metal concentrations of seawater in the dumping site (Gapo area) were observed during one tidal cycle and compared with those of seawater obtained from Jinhae Bay. The sediment was evaluated as from Non polluted to Moderately polluted by USEPA standards. It was judged that toxicological effects of sediment analyzed ranged from ERL to ERM with copper and zinc, and ERL with cadmium, chrome, lead, and nickel by the Adverse Biological Effects. The pollutant concentration was low in surface sediment compared to deeper sediment since the sediments with relatively low concentrations of pollutant were dumped to the surface. The pollutant concentration was low in surface sediment compared to deeper sediment since the sediments with relatively low concentrations of pollutant were dumped to the surface. The benthic organisms in Gapo area had higher concentrations of trace metals (Oyster: Zn 238.96, Cu 5.29 ㎍/g wet wt., Clam: Zn 17.71, Cu 1.00 ㎍/g wet wt., Mussel. Zn 187.98, Pb 0.28, Cr 0.15, Mn 4.23, Sr 1.45 and Fe 100.33 ㎍/g wet wt.) compared to outside of dumping site. However, the trace metal level in the bivalves was less than the NFPQIS (National Fisheries Products Quality Inspection Service) standard.

• Journal of the Korean GEO-environmental Society
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• v.1 no.1
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• pp.79-85
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• 2000

The environmental assessment on the open dumping landfill of small scale which was situated in local small city was carried out to reuse the landfill site as the residental, commercial and other purposes through the analysis of the leachate of landfill, extracted solution from landfill waste. The waste was landfilled at 5.5~8m depth and the covered layer so poor as 20~50cm thickness. The biodegradable organic matters were almost degraded and the result of the leachate of landfill showed that the BOD/COD ratio were measured as 0.079, pH 7.2~7.6, SS 47736mg/L, COD 6193.8mg/L, T-N 596mg/L, and T-P 123.9mg/L respectively. These results were higher than those of extracted solution of landfill waste as the COD and BOD were measured as low values and T-N 7.77mg/L and T-P as 0.20mg/L lower concentrations the landfill appears the maturation phase. As the result of the assessment on the open dumping landfill of small scale, if appears that this landfill is maturation phase and the formation leachate is reduced. If the treatment facility of leachate from landfill and the layer which protects the inflow/infiltration is prepared, it can be safely used as this landfill site.

• Journal of Environmental Science International
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• v.19 no.7
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• pp.901-905
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• 2010

Emissions of leachate, odor, and landfill gas(LFG) from an open-dumping landfill site do harm to public health by contaminating neighboring soil, underground water, and rivers. Particularly, methane($CH_4$) and carbon dioxide($CO_2$), the main components of LFG, are especially noted as the causing material of the global warming that become seriously recognized worldwide issue. As one of alternatives in managing LFG, incineration of inflammable wastes that are generated during excavation process at an open-dumping landfill has been evaluated. Standard on stabilization for evaluation, neither $CH_4$ density nor $CO_2$ density could not Because meet 'less than 5%' criterion and so it is right to install a gas collection system during landfill renewal to prevent diffusion of odor and collect it. Because it shows considerable heating value, incineration of inflammable wastes might be the reasonable solution from the result of our study.

• Journal of Environmental Science International
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• v.7 no.3
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• pp.383-392
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• 1998

Pollution characteristics of leachate and underground soul of the two landfill states were Investigated Domestic wastes were dumped In the two adjacent landfill states. Only small portion of S landifill site was filled with domestic wastes at the first stage of dumping, and most portion of the site was filled with construction wastes. However Y landfill strate was filed with mostly domestic wastes. Higher concentrations of organic pollutants including VOCs were measured In Y landfill site leachate than In S tendon site. Underground souls of the two linam states were analyzed by the two kinds of leaching methods, KEP (Korean Extraction Processl and Acid Digestion. Underground souls of the both landfill states were not polluted by leachates. Underground soils of the two were composed of firie salty material. Thus It Is fecund that fine silty soul layer of the sea shore may be used as a landfillsite.

• Journal of Urban Science
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• v.9 no.1
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• pp.69-73
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• 2020

Sudokwon landfill("Sudokwon" means regions of Seoul, Kyunggi and Incheon metropolitan cities in Korea), the world's largest sanitary landfill, has been systematically managing statistics on the incoming and dumping wastes and satisfactorily controlling pollutants including leachate and LFG. According to our long time experience of LFG field monitoring, the emission of GHG from landfill estimated by the IPCC Guideline showed much difference with our results. C&D waste has high concentration of sulfate compared to other wastes. Increased C&D waste of dumping waste had changed the COD/sulfate ratio in the landfill, which caused the increase of H₂S gas and the decrease of CH₄ gas. But the IPCC estimation method does not consider the effects of sulfate. In addition to that, the oxidation factor of the cover soil is set to the default values of 0.1 but the measured values by the field monitoring, are showing much higher than that, especially in the closed landfill.