• Journal of Soil and Groundwater Environment
• /
• v.28 no.5
• /
• pp.36-50
• /
• 2023

Soil health can deteriorate through both contamination and remediation. Accordingly, revitalization processes are needed to reuse or recycle the remediated soil. The study was conducted to assess the changes in soil health parameters of heavy metals-contaminated soil during soil washing process. In addition, unit processes were proposed to improve the quality of the remediated soil relevant to its reclamation purposes, such as agricultural and forest lands. A total of 21 indicators were used to determine whether the soil health was degraded or recovered. The performance of 6 amendments in improving soil health was quantitatively evaluated according to their dosage and application duration. Finally, the experimental results were assessed by simple regression analyses to determine the statistical significance and relative performance of each amendment. The results indicated that 18 health indicators out of 21 deteriorated through the soil washing process. Based on the results, it is recommended that several effective amendments be complementarily combined and applied in real applications because use of single amendment does not likely improve the quality of remediated soils.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2002.04a
• /
• pp.91-99
• /
• 2002

A recent survey investigated that there were over one thousand un-controlled closed landfills(1,072 sites) in Republic of Korea. Most of these landfills were constructed before 1986. Waste management act were not promulgated at that time, so they usually do not have dranage system and leachate treatment facility. Also, considerable attention has been received to landfill leachate pollution, leachate has an adverse impact on the surrounding environment such as soil, groundwater, and water supply source. According to the result of survey for closed landfill management, it was reported that 875 sites out of 1,072sites(81.6％) have no leachate treatment facility and 630 sites out of 1,072sites(58.7％) have been used for farm lands and residence. Consequently it is hard to do postclosure care continuously in most of cases and these uncontrolled landfills have contaminated farm lands and residence. The average age of these landfills are ranged mostly between 2 to 15 years. Much time and advanced technology are needed to remediate these uncontrolled landfills, therefore the survey for present status of closed landfill sites is required and suitable treatment processes should be prepared. With this point of view, We has been investigated to find out the present status of closed landfill, problems of post management and discussed plans for remediation and reuse. Remedial actions of un-controlled landfill have been carried out the many cities since 1997 upto now. Most frequently applied technology were reuse after excavation and there were several cases to capping in the surface of landfill and to construct subsurface barriers. It is considered that landfills in use have a possibility not to be controlled because of inadequate construction and improper management. Therefore remediation of uncontrolled landfills and recovery technology should be develop continuously Especially, it has been expected that resource technology of landfill gas as a energy has some advantages in controlling odors in the site area and accelerating stabilization of landfills with the energy.

• Economic and Environmental Geology
• /
• v.36 no.3
• /
• pp.191-200
• /
• 2003

Investigations on the contaminated lands due to heavy metals from mining activities or hydrocarbons from oil spillage for example, should be planned based on specific fitness-for-purpose criteria(FFP criteria). A FFP criterion is site specific or varies with situation, based on which not only the data quality but also the decision quality can be determined. The limiting factors on the qualities can be, for example, the total budget for the investigation, regulatory guidance or expert's subjective fitness-for-purpose criterion. This paper deals with planning of investigation methods that can satisfy each suggested FFP criterion based on economic factors and the data quality. To this aim, a probabilistic loss function was applied to derive the cost effective investigation method that balances the measurement uncertainty, which estimates the degree of the data quality, with the decision quality. In addition, investigation planning methods when the objectives of investigations do not lie in the classification of the land but simply in producing the estimation of the mean concentration of the contaminant at the site(e.g. for the use in risk assessment), were also suggested. Furthermore, the efficient allocation of resources between sampling and analysis was also devised. These methods were applied to the two contaminated sites in the UK to test the validity of each method.

• Korean Journal of Environmental Agriculture
• /
• v.26 no.3
• /
• pp.204-209
• /
• 2007

Agricultural area in the vicinity of the ${\triangle}{\triangle}$ smelting factory in Kyeongbuk province, the third largest zinc smelting factory in the world, was contaminated by high concentration of heavy metals. However, the heavy metals source was not yet directly traced and thus, resulted to a conflict between the factory and residents within its vicinity. In order to determine the level of heavy metal contamination in the arable lands located at the north eastern part of the factory, soils were sampled systematically. To find out the major reason for the occurrence of this problem, waters and aerosols were sampled with constant intervals to the upward and downward direction from the factory and were analyzed to find out the heavy metal concentrations. Cadmium (Cd) and zinc (Zn) of the heavy metals were highly accumulated more than the Korean warning criteria (Cd 1.5, Zn 300 mg $kg^{-1}$) with mean values 1.7 and 407 mg $kg^{-1}$, respectively, at the surface soils (0-20 cm), and heavy metal concentration significantly decreased with increasing soil depth In addition, the concentration of both metals slightly decreased with increasing distance from the factory to the surface soils. Cadmium and Zn were detected in the upward stream water with low concentration and concentrations increased significantly in the downstream after passing across the factory. Aerosol samples also showed traces of Cd and Zn which could be attributed to the contamination of the water system and the surface soils. Conclusively, Cd and Zn emitted from the ${\triangle}{\triangle}$ smelting factory moved with the aerosol in the atmosphere and thus, contaminated the agricultural areas and the water system within it vicinity.

• Proceedings of the KSRS Conference
• /
• v.2
• /
• pp.555-558
• /
• 2006

In recent years, urban development has expanded rapidly in Nawabshah City of Pakistan. A major effect associated with this population trend is transformation of the landscape from natural cover types to increasingly impervious urban land. The core objective of this study are to provide time-series information to define and measure the urban land cover changes of Nawabshah, Pakistan between the years 1992 and 2002, and to examine related urbanization impacts on air quality of the study area. Two multi-temporal Landsat images acquired in 1992 and 2002 together with standard topographical maps to measure land cover changes were used in this study. The image processing and data manipulation were conducted using algorithms supplied with the ERDAS Imagine software. An unsupervised classification approach, which uses a minimum spectral distance to assign pixels to clusters, was used with the overall accuracy ranging from 84 percent to 92 percent. Land cover statistics demonstrate that during the study period (1992-2002) extensive transformation of barren and vegetated lands into urban land have taken place in Nawabshah City. Results revealed that land cover changes due to urbanization has not only contaminated the air quality of the study area but also raised the health concerns for the local residents.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.3
• /
• pp.296-303
• /
• 2010

Chromium as a constituent of rocks occurs naturally in the environment in varying concentrations. However, the human activity has changed the geochemical cycle of chromium in the environment and has caused the chromium accumulation in soils. Korean soils revealed a wide range of chromium contents depending on parent material and land use. The total chromium contents of volcanic ash soils in Jeju, which were determined using $HNO_3$ + $HClO_4$ + HF, ranged from 434 to 1,164 mg $kg^{-1}$. The 'ecological' total chromium contents extracted using conc. HCl + conc. $HNO_3$ (aqua regia) in the same soils varied in a lower range of 50-189 mg $kg^{-1}$ (averaged percentage of aqua regia contents in $HNO_3$ + $HClO_4$ + HF contents: 14.9%). Serpentine soils in Andong showed a 'ecological' total chromium content of 309 mg $kg^{-1}$ and against it granitic soils in Andong only 20 mg $kg^{-1}$. In uncontaminated forest soils of Korea, the 'ecological' total chromium contents varied from 4.89 to 106 mg $kg^{-1}$ and the soluble chromium contents determined using 0.1 M HCl ranged from 0.01 to 0.64 mg $kg^{-1}$ (averaged percentage of 0.1 M HCl contents in aqua regia contents: 0.4%). Arable lands contained more soluble chromium than reported in forest soils (averaged soluble chromium: 0.36 and 0.09 mg $kg^{-1}$, respectively). In particular, the soluble chromium contents in greenhouse, orchard and upland soils were higher than in contaminated soils near mine and industrial site (maximum contents: greenhouse 15.3 mg $kg^{-1}$; upland 12.1 mg $kg^{-1}$; orchard 8.29 mg $kg^{-1}$; mine site 4.76 mg $kg^{-1}$; industrial site 2.80 mg $kg^{-1}$). On the basis of these results a accumulation of chromium in some specific arable lands can be assumed, probably by long-continued applications of fertilizers or soil amendments containing chromium. In Korean Enforcement Decree of the Soil Environment Conservation Act soil standards for total chromium do not exist yet.

• Economic and Environmental Geology
• /
• v.28 no.3
• /
• pp.221-229
• /
• 1995

The heavy metal contents and their dispersion patterns in stream water, stream sediments, land plants and aquatic larvae collected from the hydrologic system flowing via the wasted ore dump of the Moak Au-Ag mine were investigated systematically in order to evaluate the environmental impacts of the abandoned metal mine. The heavy metal content increases abruptly in the vicinity of the wasted ore dump, then attenuated with increasing distance from the mine area. Attenuating rates were stream water > stream sediments > land plants > aquatic larvae. On the other hand, the cumulative content of heavy metals was stream sediments >aquatic larvae > land plants > stream water. Each element tends to be enriched selectively according to media; Zn > Cu > Cd > Pb in stream water, Zn > Pb > Cu > Cd in stream sediments and land plants, and Zn > Cu > Pb > Cd in aquatic larvae. These results show that the degree of enrichment and dispersion of pollutant extruded from the wasted ore dump are different according to elements and media, and that the circulation system of materials of each medium is different. The heavy metals, especially Cu, Pb and Zn, of polluted downstream sediments occur in high proportions of Fe-Mn oxides and organic bounded forms, which show high potential of a secondary pollution source. The content of heavy metals and their dispersion patterns in stream sediments are different from those of ten years ago; pollution levels of heavy metals were degraded in various ranges. The Zn and Cu-polluted areas were widened whereas Fe and Pb-polluted areas were reduced. In crops collected from the farm lands in downstream area, the pepper was more concentrated in all heavy metal than rice. The pepper showed some contaminated level in Cu(9.7ppm) and Zn(149ppm), and the rice in Zn(90ppm). However, both crops showed no significant level in Cd(<0.2ppm) and Pb(<0.5ppm).

• Korean Journal of Soil Science and Fertilizer
• /
• v.47 no.3
• /
• pp.191-198
• /
• 2014

Absorption and accumulation of heavy metals in plants were determined by phytoavailable contents rather than total contents of heavy metals. Therefore, phytoavailability-based management protocol should be prepared for safe food crop production in contaminated agricultural lands. This study was conducted to understand the distribution and phytoavailability of heavy metal in the Korean agricultural soils affected by abandoned mining sites along with investigation of soil properties (soil pH, OM, DOC, clay content, Al/Fe/Mn content) influencing on the metal phytoavailability. For this, 142 agricultural soils located nearby 39 abandoned mining sites distributed in five province in Korea, were analyzed. Among the four different heavy metals, cadmium (Cd) and zinc (Zn) appeared to exist in more phytoavailable form than cupper (Cu) and lead (Pb). Soil pH was the main factor governing phytoavailable Cd, Pb, and Zn showing positive relationship with partitioning coefficients of the corresponding metals; Cd (r = 0.66, P < 0.001), Pb (r = 0.70, P < 0.001), and Zn (r = 0.62, P < 0.001). This implied higher phytoavailability of the corresponding metals with higher soil pH. In contrast, phytoavailability of Cu (r = 0.41, p < 0.01) was only negatively related with soil DOC (dissolved organic carbon).

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.6 no.2
• /
• pp.16-27
• /
• 2003

For the last decade, some 400 small and large oil spill accidents have occurred every year. Such accident blow a serious damage to the marine resource and ecosystem, which can't be estimated in terms of economic and environmental losses. The physical/chemical methods used currently may be effective at the initial stage of accidents, but they can't serve to remove the spilled oil completely. Moreover, the dispersant may lead to a secondary contamination detrimental to the lives inhabiting wet lands, beaches and tidal zone. Thus, a new decomposing technology Is required for the environmentally sensitive areas. Bioremediation is the active use of biological techniques to mitigate the consequences of a spill using biological processes and refers both of stimulation of pollutant biodegradation and/or to enhance ecosystem recovery Bioremediation is an economically attractive method for the clean-up of oil-contaminated area. Bioremediation has been demonstrated to be an effective oil spill countermeasure for use in cobble, sand beach, salt marsh, and mud flat environment.

• Journal of Soil and Groundwater Environment
• /
• v.14 no.2
• /
• pp.33-44
• /
• 2009

The objective of the study was to develop a hybrid technology integrating biological and physicochemical technologies to efficiently remediate arsenic contaminated lands such as abandoned mine area. The tailing soil samples contaminated with As at a high level were obtained from Songchon abandoned mine, and the content of arsenic and heavy metals as well as physicochemical properties and mineral composition were investigated. In addition, two sets of sequential extraction methods were applied to analyze chemical speciations of arsenic and heavy metals to expect their leachability and mobility in geoenvironment. Based on these geochemical data of arsenic and heavy metal contaminants, column-type experiments on the bioleaching of arsenic were undertaken. Subsequently, experiments on the hybrid process incorporating bioleaching and electrokinetics were accomplished and its removal efficiency of arsenic was compared with that of the individual electrokinetic process. With the results, finally, the feasibilty of the hybrid technnology was evaluated. The arsenic removal efficiencies of the individual electrokinetic process (44 days) and the hybrid process incorporating bioleaching (28 days) and electrokinetics (16 dyas) were measured 57.8% and 64.5%, respectively, when both two processes were operated in an identical condition. On the contrary, the arsenic removal efficiency during the bioleaching process (28 days) appeared relatively lower (11.8%), and the result indicates that the bioleaching process enhanced the efficacy of the electrokinetic process as a result of mobilization of arsenic rather than removed arsenic by itself. In particular, the arsenic removal rate of the electrokinetics integrated with bioleaching was observed over than 2 times larger than that obtained by the electrokinetics alone. From the results of the study, if the bioleaching which is considered a relatively economic process is applied sufficiently prior to electrokinetics, the removal efficiency and rate of arsenic can be significantly improved. Consequently, the study proves the feasibility of the hybrid process integrating both technologies.