• Journal of Korea Soil Environment Society
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• v.1 no.1
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• pp.47-54
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• 1996

Soil pollution indices (SPI) were designed for estimating quality of soil polluted with arsenic and heavy metals. Applying the quality reference value of soil based on its multifunctional purpose was a key step. For considereing multifunctions of soil, soil was classified into 4 groups-agricultural land, residential area, recreational area, factorial site. Then, each concentration of arsenic and each of five heavy metals (Cd, Cu, Hg, Pb, Zn) in soils grouped was transformed to a mathematical value based on the soil quality reference value which may stand for ecological impact. Soil pollution score (SPS) was the addition of the 6 values transformed, and the range of the SPS was divided into 4 Soil Pollution Classes (SPC). The SPC 1, 2, 3, and 4 were SPS <100, SPS 100-200, SPS >200-300, and SPS >300, repectively. SPS and SPC were evaluated with the results of the data from employing the Soil Network of 1994. Based on the soil quality reference values, SPS and SPC of the Soil Network's data were transformed and classified, respectively. Then, SPS and SPC were compared with arsenic and the 5 heavy metal contents of their reference values resulted from the Soil Network's. From this method, soil quality of most of the Soil Network area was estimated to be healthy. However, ca. 3.0~4.0% of the Soil Network area was determined in a range of slightly and heavily polluted. As the mean value of SPS of the Soil Network's was 66.2 which indicates most of soil evaluated was healthy. When the SPSs of the data were divided into 4 groups of SPC, Class 1 (Good quality of soil), Class 2 (Need to be checked area 1), Class 3 (Need to be checked area 2) and Class 4 (Polluted area) were 87.0, 9.4, 2.4, 1.2%, respectively. Using SPI were comparable to those of heavy metal contents in soils, and would be comprehenve to determine the status of soil qulity. Methodology of the developing SPI would be applicable to the other soil pollutants such as organic and inorganics than arsenic and 5 heavy metals used here.

• Journal of Korea Soil Environment Society
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• v.1 no.2
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• pp.23-34
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• 1996

The biological magnification of Pb, Cu, Zn and Fe in vascular plant, Persicaria thunbergii, Trapa japonica and Nymphoides peltata natually grown at the river and riverside and relationship between the concentration of heavy metals in these vascular plants and in the soil were investigated in the Chonju river, Chonju city. The biological magnification values of these metals in P thunbergii were founded as follows ; Pb, Cu, Zn and Fe were 80.4~254.6$mu\textrm{g}$/g, 284.6~688.4$mu\textrm{g}$/g, 635.5~1979.4$mu\textrm{g}$/g and 1160.0~3590.9$mu\textrm{g}$/g respectively. In the case of T. japonica, Pb, Cu, Zn and Fe were 107.8~306.0$mu\textrm{g}$/g, 282.7~963.0p$mu\textrm{g}$/g, 1328.3~3546.$mu\textrm{g}$/g and 656.8~9944.0$mu\textrm{g}$/g and in N. peltata, 140.1~ 193.9$mu\textrm{g}$/g, 187.7~327.3$mu\textrm{g}$/g, 1126.6~1723.6$mu\textrm{g}$/g and 611.7~1914.6$mu\textrm{g}$/g respectively. The amount of the biological magnification of heavy metals in the leaf, stem and root of these plants was generally increased in the sequence of leaf

• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.81-94
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• 1997

In many solute transport studies, either flux or resident concentration has been used. Choice of the concentration mode was dependent on the monitoring device in solute displacement experiments. It has been accepted that no priority exists in the selection of concentration mode in the study of solute transport. It would be questionable, however, to accept the equivalency in the solute transport parameters between flux and resident concentrations in structured soils exhibiting preferential movement of solute. In this study, we investigate how they differ in the monitored breakthrough curves (BTCs) and transport parameters for a given boundary and flow condition by performing solute displacement experiments on a number of undisturbed soil columns. Both flux and resident concentrations have been simultaneously obtained by monitoring the effluent and resistance of the horizontally-positioned TDR probes. Two different solute transport models namely, convection-dispersion equation (CDE) and convective lognormal transfer function (CLT) models, were fitted to the observed breakthrough data in order to quantify the difference between two concentration modes. The study reveals that soil columns having relatively high flux densities exhibited great differences in the degree of peak concentration and travel time of peak between flux and resident concentrations. The peak concentration in flux mode was several times higher than that in resident one. Accordingly, the estimated parameters of flux mode differed greatly from those of resident mode and the difference was more pronounced in CDE than CLT model. Especially in CDE model, the parameters of flux mode were much higher than those of resident mode. This was mainly due to the bypassing of solute through soil macropores and failure of the equilibrium CDE model to adequate description of solute transport in studied soils. In the domain of the relationship between the ratio of hydrodynamic dispersion to molecular diffusion and the peclet number, both concentrations fall on a zone of predominant mechanical dispersion. However, it appears that more molecular diffusion contributes to the solute spreading in the matrix region than the macropore region due to the nonliearity present in the pore water velocity and dispersion coefficient relationship.

• Journal of Korea Soil Environment Society
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• v.2 no.3
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• pp.3-21
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• 1997

The remediation of contamiated sites using currently available remediation technologies requires long term treatment and huge costs, and it is uncertain to achieve the remediation goal to drop contamination level to either back-ground or health-based standards by using such technologies. Intrinsic remediation technology is the remediation technology that relies on the mechanisms of natural attenuation for the containment and elimination of contaminants in subsurface environments. Initial costs for the intrinsic remediation may be higher than conventional treatment technologies because the most comprehensive site assessment for intrinsic remediation is required. Total remediation cost, however may be the lowest among the presently employed technologies. The applicability of intrinsic remediation in the contaminated sites should be theroughly investigated to achieve the remedial goal of the technology. This paper provides the frame of the extended site assessment procedure based on knowledge of biodegradability to evaluate the applicability of intrinsic remediation. This site assessment procedure is composed of 5 steps such as preliminary site screening, assessment of the current knowledge of biodegradability, selecting the appropriate approach, analyzing the contaminant fate and transport and planning the monitoring schedule. In the step 1, followings are to be decided 1) whether to go on the the detailed assessment or not based on the rules of thumb concerning the biodegradability of organic compounds, 2) which protocol document is selected to follow for detailed site assessment according to the site characteristics, contaminants and the relative distance between the contamination and potential receptors. In the step 2, the database for biodegradability are searched and evaluated. In the step 3, the appropriate biodegradability pathways for the contaminated site is selected. In the step 4, the fate and transport of the contaminants at the site are analyzed through modeling. In the step 5, the monitoring schedule is planned according to the result of the modeling. Through this procedure, users may able to have the rational and systematic informations for the application of intrinsic remediation. Also the collected data and informations can be used as the basic to re-select the other remediation technology if it reaches a conclusion not to applicate intrinsic remediation technology at the site from the site assessment procedure.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.212-219
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• 2004

To minimize the danger of soil erosion and settle habitats earlier, afforestation, which vegetates bare slopes, is selected as an environmental recovering technology. Large portions of these areas often are suffered by a bad germination and growth inhibition of sprayed seeds. Afforested materials collected in the normal and damaged sites were not any big difference in chemical characteristics and biological response to ryegrass. But background soil of the damaged site has very low pH (3.6) and high contents of iron and aluminum compared with them of the normal sites. Both germination and root growth of ryegrass were inhibited severely in the water extracts of damaged soils, but not in the water extracts of normal sites. Groundwater collected nearby the damaged sites was very strong acidic (pH 33) and exhibited a high value of electrical conductivity and high contents of iron and aluminum. In the ground water, germinated ryegrass was scarcely grown. In Al standard solution, the root growth of ryegrass was inhibited over 50% in 0.5 mM in pH 3.5-4.5 and in 1.4 mM in pH 5.5, which seems to be related to $Al^{3+}$ activity in solution. In the ferric Fe ($Fe^{3+}$) standard solution, ryegrass growth was inhibited over 50% in the concentration of 14-19 mM in root and 23-25 mM in shoot. This strong tolerance of ryegrass to $Fe^{3+}$ might be concerned with the very low activity of $Fe^{3+}$ at pH 3.5-5.5. In contrast, ryegrass responded very sensitively to ferrous Fe ion ($Fe^{2+}$), especially in root growth: $Fe^{2+}$ concentrations corresponding to 50% growth reduction were 0.3-0.4 mM at pH 3.5-5.5 in roots. This high growth inhibition should be related to the high ion activity of $Fe^{2+}$ irrespective of different pH conditions. In conclusion, low pH and high contents of $Fe^{2+}$ and aluminum seem to be caused by pyrite and be closely related to the growth inhibition of ryegrass seeded in afforested area.

• Journal of the Mineralogical Society of Korea
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• v.25 no.4
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• pp.185-195
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• 2012

Due to the high reduction and sorption capacity as well as the large specific surface area, nanosized mackinawite (FeS) is useful in reductively transforming chlorinated organic pollutants and sequestering toxic metals and metalloids. Due to the dynamic nature in its colloid stability, however, nanosized FeS may be washed out with the groundwater flow or result in aquifer clogging via particle aggregation. Thus, these nanoparticles should be modified such as to be built into permeable reactive barriers. This study employed coating methods in efforts to facilitate the installation of permeable reactive barriers of nanosized mackinawite. In applying the methods, nanosized mackinawite was coated on non-treated silica sand (NTS) and chemically treated silica sand (CTS). For both silica sands, the maximum coating of mackinawite occurred around pH 5.4, the condition of which was governed by (1) the solubility of mackinawite and (2) the surface charge of both silica and mackinawite. Under this pH condition, the maximum coating by NTS and CTS were found to be 0.101 mmol FeS/g and 0.043 mmol FeS/g respectively, with such elevated coatings by NTS likely linked with impurities (e.g., iron oxides) on its surface. Arsenite sorption experiments were performed under anoxic conditions using uncoated silica sands and those coated with mackinawite at the optimal pH to compare their reactivity. At pH 7, the relative sorption efficiency between uncoated NTS and coated NTS changed with the initial concentration of arsenite. At the lower initial concentration, uncoated NTS showed the higher sorption efficiency, whereas at the higher concentration, coated NTS exhibited the higher sorption efficiency. This could be attributed to different sorption mechanisms as a function of arsenite concentration: the surface complexation of arsenite with the iron oxide impurity on silica sand at the low concentration and the precipitation as arsenic sulfides by reaction with mackinawite coating at the high concentration. Compared to coated NTS, coated CTS showed the lower arsenite removal at pH 7 due to its relatively lower mackinawite coating. Taken together, our results indicate that NTS is a more effective material than CTS for the coating of nanosized mackinawite.

• Economic and Environmental Geology
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• v.41 no.1
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• pp.63-79
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• 2008

Physicochemical characteristics of stream water, leachate, mine water and groundwater were investigated to estimate the influences of the tailing and waste rock from the abandoned Uljin mine area. Total extraction analysis and mineralogical studies were carried out to understand sulfide weathering and to determine the distributions of trace elements in the soil affected by mine waste (tailing, waste rock and leachate). The pH and EC value of the leachate from the tailing disposal ranged 2.9-6.0, $99{\sim}3,990{\mu}S/cm$, respectively, and the concentrations of dissolved major (up to 492 mg/l Ca; 83.8 mg/l Mg; 45.2 mg/l Na; 44.7 mg/l K, 50.8 mg/l Si) and trace elements (up to $826,060{\mu}g/l$ Fe; $131,230{\mu}g/l$ Mn; $333,600{\mu}g/l$ Al; $61,340{\mu}g/l$ Zn; $2,530{\mu}g/l$ Cu; $573{\mu}g/l$ Cd; $476{\mu}g/l$ Pb) were relatively high. The stream water showed the variation of dissolved metal concentrations in seasonally and spatially. The dissolved metal contents of the stream water increased by influx the leachate from the tailing disposal, but these of the down stream have been considerably decreased by mixing of dilute tributaries. The dissolved metal concentrations of the stream water at dry season (as February) were lower than these at rainy season (as May and July). These represent that the amounts of the leachate varied with season. However, stream water could not be effectively diluted by confluence with uncontaminated tributaries, because the flux of tributaries and streams reduced at dry season. Thus attenuations by dilution had been dominantly happened in rainy seasons. The order of accumulations of trace element in soils compared with background values revealed Mn>Fe>Pb>Cu>Zn. Sulfide minerals were mainly pyrrhotite, sphalerite and galena and chalcopyrite. Pyrrhotite was rapidly weathered along the edge and fractures, and results in the formation of Fe-(oxy)hydroxides, which absorbed a little amount of Zn.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.13-29
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• 1998

Recently, It is increasing popularity to research on the soil remediation in aspect of management by reason of the hazardous impact on the contaminated soil in Korea. It was investigated high levels of arsenic salts in soil near abandoned five mines(Darak, Daduk, Jingok, Dalsung, Ilkwang) located in Youngnam area. Arsenic, classified as group A(Human Carcinogens) from IRIS, have shown statistically significant increment in skin cancer with oral exposure. This paper was conducted to predict excess cancer risk value (to the skin cancer) based on multiple pathway such as soil ingestion, dermal uptake and food(plant) ingestion contaminated by arsenic, and also, to identify the remedial goal regarded in future land use. The mine having the highest arsenic level was Daduk(mean : 1950mg/kg) and the next rank was Jingok(1690mg/kg), Ilkwang(352.37mg/kg), Dalsung(86.08mg/kg), Darak(0.83mg/kg). The chronic daily intake to the multiple exposure were calculated using Monte-Carlo simulation regarded in future land use and used q: value was $1.5(mg/kg/day)^{-1}$ to the oral proposed by IRIS(1997). The computated excess cancer risk 95th value to all the mine regarding future land use as residential and rural area were more than $10^{-4}$. If the level of acceptable risk is aimed for 1$\times$$10^{-6}$, it could be used Darak as commercial and industrial area without soil remediation due to the lowest risk value(6$\times$$10^{-8}$ and 3$\times$$10^{-8}$). Computated remedial goal based on 1$\times$$10^{-6}$ of acceptable risk to the future land use as the residential, rural, commercial and industrial area were 0.02mg/kg, 0.003mg/kg, 97.31mg/kg and 194.62mg/kg, respectively.

• Journal of Life Science
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• v.30 no.2
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• pp.156-161
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• 2020

Since industrialization, the production and utilization of various chemicals has contributed to improving the quality of our lives, but the subsequent discharge of massive waste is inevitable, and environmental pollution is becoming more serious every day. Exposure to chemicals as a result of environmental pollution is having a negative effect on human health and the ecosystem, and cleaning up the polluted environment that can affect our lives is a very important issue. Toxic aromatic compounds have been detected frequently in soil, groundwater, and wastewater because of the extensive use of oil products, and phenol, which is used to produce synthetic resins, textiles, and dyes, is one of the major pollutants, along with insecticides and preservatives. Phenol can cause dyspnea, headache, vomiting, mutation, and carcinogenesis. Phenol-degrading bacterium DWB-1-8 was isolated from the activated sludge of textile wastewater; this strain was identified as Comamonas testosteroni by 16S rRNA gene sequencing. The optimal culture conditions for the cell growth and degradation of phenol were 0.7% K₂HPO₄, 0.6% NaH₂PO₄, 0.1% NH₄NO₃, 0.015% MgSO₄·7H₂O, 0.001% FeSO₄·7H₂O, an initial pH of 7, and a temperature of 30℃. The strain was also able to grow by using other toxic compounds, such as benzene, toluene, or xylene (BTX), as the sole source of carbon.

• Journal of Korean Society of Rural Planning
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• v.24 no.3
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• pp.73-86
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• 2018

Agricultural or rural landscape provides various ecosystem services. However, the ecosystem services function is declining due to various environmental problems such as climate change, land use change, stream intensification, non-point pollution and garbage. The A1B scenario predicts that the mean air temperature of South Korea will rise $3.8^{\circ}C$ degrees celsius in 2100. Agricultural sector is very vulnerable to climate change, so it must be thoroughly predicted and managed. In Korea, the facility horticulture complex is 54,051ha in 2016 and is the 3rd largest in the world(MAFRA, 2014). Facilities of horticultural complexes are reported to cause problems such as groundwater decrease, vegetation and insects diversity reduction, landscapes damage and garbage increase, compared with the existing land use paddy fields. Heat island phenomenon associated with climate change is also accelerated by the high heat absorption of horticultural sites. Therefore, we analyzed the heat island phenomenon occurring in the facility of horticultural complex in Korea. As an improvement measurement, I examined how much air temperature is reduced by putting the channel and the open space. In the case of the Buyeo area, the Computational Fluid Dynamics (CFD) simulation was analyzed for the average summer temperature distribution in the current land use mode at $38.9^{\circ}C$. As an improvement measurement, CFD simulation after 10% of 6m water channel was found to have an effect of lowering the summer temperature of about $2.7^{\circ}C$ compared with the present average of $36.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $34.7^{\circ}C$, which is $4.2^{\circ}C$ lower than the present. For the Jinju area, CFD simulations were analyzed for the average temperature of summer at $37.8^{\circ}C$ in the present land use pattern. As an improvement measure, CFD simulations after 10% of 6m water channel were found to have an effect of lowering the summer temperature of about $2.6^{\circ}C$ compared to the current average of $35.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $33.9^{\circ}C$, which is $3.9^{\circ}C$ lower than the present. It can be said that the effect of summer temperature drop in open space and waterway has been proven. The results of this study are expected to be reflected in sustainable agriculture land use and used as basic data for government - level policy in land use planning for climate change.