• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.3
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• pp.246-254
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• 2013

This study is purposed to verify the safety of the floor of the children's playground using polyolefin foam waste and rubber paving. The critical fall height, walking suitability, long term physical fatigue expectation and slipperiness were tested. Polyolefin foam wastes in thickness of 30mm, 50mm and 70mm were prepared with paving the rubber paving materials in 12mm and 15mm thickness respectively. The test on the critical fall height was carried out according to KS G 5758:2009. The floor hardness test equipment (O-Y HMA) was used for the test on hardness of the floor from a viewpoint of walking suitability and fatigue. A portable slipperiness tester (ONO PPSM) was used for slipperiness test. It was revealed from the test that the floor made of the polyolefin foam waste and rubber paving were considerably safe from a viewpoint of impact absorption. With regards to the hardness of the floor, it was shown the excellent performance in the aspects of walking and fatigue for male. But it was not suitable with walking on the shoes(middle heels) for female. And they will be very fatigue if they were in a long time walking or standing. As far as the slipperiness is concerned, it was shown that it was comparatively safe for the ordinary motions even though the surface was wet.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.37-43
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• 1996

The high Temperatures and long residence times in the combustion zones of cement kiln can use to burn liquid and solid wastes, such as fuel-wastes, sludges and tire-wastes. To the lastest time, treatment methods of industrial waste are incineration treatment, ocean dumping and land dumping. These are the main methods, but all of them may cause vatious kinds of secondary pollution, including air pollution and water pollution. From this point of view, to reuse the Reclaiming-Fuel in Cement Kiln is the most outstanding waste treatment plant in the world and dose not cause any pollution at all.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.489-493
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• 2001

Big cities in Japan have serious problems due to the shortage of new reclaimed land for municipal wastes. If harmful heavy metals such as cadmium, lead, copper and etc. are contained in the municipal waste combustion residues, they are not able to fill up according to the environmental law in Japan. In this study, the removal of heavy metals in the fly ash (EP ash) was dealt with chloridizing vaporization method. EP ash as a non-hazardous materials is utilized as covering materials, road bed, and building materials.

• Korean Management Science Review
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• v.21 no.2
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• pp.1-14
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• 2004

This paper presents a review on the operations research modeis for environmental management including water, land, and air poliution in the environmental chain and including waste treatment, reverse logistics, and product recovery in the supply chain for last 30 years. The integrated and globalized environmental issues have given OR professionals a lot of natural opportunities for an effective environmental management with mathematical programming and computer simulation tool.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.172-185
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• 2009

This paper presents case histories and research projects related to geotechnical challenges at waste landfill sites in Japan. Due to the limitation of inland space available to waste disposal, coastal landfills and the associated containment systems are important considerations, particularly for metropolitan areas. Experimental works on heavy metals mobility using a large column to simulate the redox potential at the coastal landfill sites are introduced. After the closure of landfill sites, they are expected to be utilized as new land space, since new space is difficult to find in urban area. In the redevelopment of such closed landfill sites, there are possibilities of environmental risks, such as generation of toxic gas and leachate, differential settlement of the waste layer, damage to the lining system. Whether the pile installation through the clay layer acting as a landfill bottom barrier is environmentally acceptable or not has been a great concern in the redevelopment of closed waste landfill sites in particular coastal landfill sites. An analytical study to evaluate the cost-effective remedial option for a dumped waste site located along a landslide area, where cut-off wall keyed into the aquitard might elevate groundwater level and thus may not be employed, is presented.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1245-1252
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• 2010

Many industrialized countries are confronted with a difficulty about reuse of closed waste landfill. facilities. Especially, the demand of closed waste landfill maintenance and reuse nearby urban area has been increased, because of the shortage of usable land and extend of urban area. For the safe reuse of closed waste landfill, the most important check point is the effect of waste landfill on environment abound them. However, the non-sanitary closed waste landfill generally have no leachate lining system, therefore, the in-situ lining system such as sheet-pile, and vertical slurry wall etc. was needed to prevent the leachate outgoing from the waste landfill. In this paper present the case history of performance evaluation of vertical slurry wall by tracer tests.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.301-308
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• 1999

With the shortage of the land and NIMBY syndrome, it is issued recently that the capacity of waste-landfill site is needed though the decreasing tendency of waste landfill. From this point, the stability is the most essential problem in the landfill that will be constructed. Advanced design and construction are most important for that. In this paper, for the study of desiccation, dry-shrinkage crack from drying and chemical reaction in cement hydration, which is occurred when the surface layer stabilization method is applied in wast landfill, laboratory test of the ground and specimen according to the mixture ratio of stabilizer is performed. From the result, it is notified that the uni-axial strength increases with the stabilizer, but dry-shrinkage increases too, therefore, it is important and the goal of this study to find the optimal mixture ratio of each stabilizer. Analysis of variance for regression with acting variables is performed to find optimal mixture ratio of each stabilizer.

• Journal of Environmental Health Sciences
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• v.30 no.5 s.81
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• pp.388-394
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• 2004

Seaweed waste(SWW) was used to improve the liner effect in recycling of dredged soil as the landfill liner. It was found that the compressive strength became somewhat lower when SWW was added than that was when Ordinary Port-land Cement(OPC) only was added. The permeability coefficient, however, became lower in this case which showed the lowest permeability coefficient when the addition of SWW was one percent. Hence, to comply with the regulations for the compression strength and permeability coefficient of landfill liner, the addition of OPC should be over eight percent and that of seaweed waste one percent. The results of leaching test showed that the solidified material was not against the laws of waste control, so it is possible to use as the landfill liner and to expect sufficient economic effects because wastes such as dredged soil and seaweed can be recycled.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.1
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• pp.21-33
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• 2016

Estimation of groundwater hydrologic cycle pattern is one of the most critical issues in sustainable management of groundwater resources in coastal area. This study estimated groundwater percolation by using the water balance methodology and hydrogeological characteristics of land use and soil. Evapotranspiration was computed by using the Thornthwaite method, and surface runoff was determined by using the SCS-CN technique. Groundwater storage change was obtained as 229 mm/a (17.8% of the average annual rainfall, 1286 mm/a), with 693 mm/a (60.1%) of evapotranspiration and 124 mm/a (9.6%) of surface runoff. Rainfall and groundwater storage change was highly correlated, comparing with the relationships between rainfall and evapotranspiration, and between rainfall and surface runoff. This result indicates that groundwater storage change responds more sensitively to precipitation than evapotranspiration and surface runoff.

• Nuclear Engineering and Technology
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• v.23 no.2
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• pp.219-232
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• 1991

Radioactive waste accepted to the repository of land disposal should have the capability of a safe isolation. To develop those requirements and evaluation techniques, the foreign criteria and the important characteristics, relevant to waste forms and management processes, were reviewed. Based on such studies as the evaluation techniques, “general acceptance criteria”that the radioactive waste forms generated in Korea should be met were suggested.