• Journal of Environmental Impact Assessment
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• v.25 no.6
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• pp.414-431
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• 2016

There are numerous closed and abandoned mines in Korea, from which diverse heavy metals (e.g., As, Cd, Cu, Pb, Zn) are released into the surrounding soil, groundwater, surface water, and crops, potentially resulting in detrimental effects on the health of nearby residents. Therefore, we performed human risk assessments of two abandoned metal mines, Yanggok (YG) and Samsanjeil (SJ). The exposure parameters used in this assessment were specific to residents near mines and the included exposure pathways were relevant to areas around metal mines. The computed total excess carcinogenic risks for both areas exceeded the acceptable carcinogenic risk ($1{\times}10^{-6}$), indicating that these areas are likely unsafe due to a carcinogenic hazard. In contrast, the non-carcinogenic risks of the two areas differed among the studied receptors. The hazard indices were higher than the unit risk (=1.0) for male and female adults in YG and male adults in SJ, suggesting that there are non-carcinogenic risks for these groups in the study areas. However, the hazard indices for children in YG and female adults and children in SJ were lower than the unit risk. Consumption of groundwater and crops grown in the area were identified as major exposure pathways for carcinogenic and non-carcinogenic hazards in both areas. Finally, the dominant metals contributing to carcinogenic and non-carcinogenic risks were As and As, Cu, and Pb, respectively. In addition, the carcinogenic and non-carcinogenic risks of YG were evaluated to be 10 and 4 times higher than those of SJ, respectively, resulted from the relatively higher exposure concentration of As in groundwater within SJ area. Because of lacking of several exposure parameters, some of average daily dose (ADD) could not be computed in this study. Furthermore, it is likely that the ADDs of crop-intake pathway included some errors because they were calculated using soil exposure concentrations and bioconcentration factor (BCF) rather than using crop exposure concentrations.

• Journal of the Korean GEO-environmental Society
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• v.8 no.2
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• pp.5-9
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• 2007

This study carried out to investigate the removal capacity of heavy metals such as Cu (II), Zn (II) and Cd (II) dissolved in aqueous solution in the soils collected from Hyeon-Dong (HD), San-seong (SS), Keum-chon (KC) and Keum-Hac (KH) located in the upper Banbyun stream. The pH of all the soils was weak alkali such as 8.8 9.2. According to the analysis of chemical composition of the soils, the amount of $SiO_2$, $AlO_2$ and CaO were similar in all tested soils. However, the amount of $K_2O$, $FeO_3$ and MgO were different from each soil. The XRD measurement with these soils showed that quartz and feldspar were presented in all tested soils, and the distribution of kaoline, illite, montmorillonite, vermiculite and calcite were different from each soil. The results of the removal capacity of heavy metals indicated that all the soils had more than 98% of the removal efficiency of Cu (II), Zn (II) and Cd (II), and among the heavy metals, Cu (II) was removed the most effectively. These results suggested that the soils collected from the upper Banbyun stream have the high removal capacity of heavy metals, and these soils could be used for the banking a river around the abandoned mine area, containing the higher concentrations of heavy metals than the usual stream.

• Journal of Soil and Groundwater Environment
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• v.12 no.6
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• pp.100-106
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• 2007

The objective of this study was to evaluate the efficiency of $(NH_4)_2HPO_4$, $Na_2HPO_4{\cdot}12H_2O$, $CaHPO_4{\cdot}2H_2O$, $Ca(H_2PO_4)_2{\cdot}H_2O$ and $H_3PO_4$ for the stabilization of soils contaminated with multi-metals containing Pb, Cd and As. The application rate of stabilizers to soils was determined based on $PO_4/Pb_{total}$ molar ratio of 0.5, 1, 2, 4. The results of Korea Standard Test and TCLP (EPA Method 1311) showed the reduction of metal leachabilities below the regulatory limits for Pb and Cd when $H_3PO_4$ and $Ca(H_2PO_4)_2{\cdot}H_2O$ were applied. However, stabilization efficiency for Cd was low and in case of As leaching concentration increased rather. It is considered that $PO_4$ reacted effectively $Pb^{2+}$ due to leaching Pb under low pH condition created by adding $H_3PO_4$. Accordingly Pb was stabilized by dissolution and precipitation of hydroxypyromorphite. From the change of metals fraction using sequential extraction procedure when $H_3PO_4$ applied as a stabilizer, we confirmed that residual fraction increased more than 60% and this result was accorded with XRD analysis that detected only hydroxypyromorphite peak in $H_3PO_4$.