• The Journal of Engineering Geology
• /
• v.16 no.2 s.48
• /
• pp.153-159
• /
• 2006

The discharges of time, technology and finance was increased and it was difficult to use water resources effectively by serious water pollutions. Thus the main aim of this work was focused on effectiveness of water treatment process using non-controlled indicators such as UV absorbance($E_{260}$) and particle counts that provided analytical results with simple and rapid. The soluble aluminum was increased by the increase of aluminum doses for turbidity removals It means that the water quality was not controlled by only turbidity monitoring cause maximum turbidity removal did not guarantee minimum residual aluminum in an aluminum-based coagulation. E removal efficiency appeared to be the promising indicator for monitoring the effectiveness of the water quality process such as coagulation and nanofiltration membranes for arsenic(V). On the basis of the particle monitoring, it was also found that the particle counts could be used very useful for changing the coagulants in real water treatments.

• Korean Journal of Ecology and Environment
• /
• v.41 no.1
• /
• pp.66-72
• /
• 2008

Total metals, soluble metals, and bioavailable metals were monitored at the sediments of urban lakes located in Seoul, Korea during spring season 2006. The metals measured were zinc, arsenic, chromium, copper, nickel, and cadmium, which are known to be toxic to human health and ecosystems. The main sources of heavy metals in the lakes were urban runoff and atmospheric deposition associated with air pollution in urban areas. Extraction by using a weak electrolyte solution (0.1 M $Ca(NO_3)_2$) was used to predict bioavailability of the metals. Among the six heavy metals studied, copper was the most bioavailable, based the weak electrolyte extraction techniques. Since metal toxicity is related to metal bioavailability, the results were consistent with the high ecotoxicity of copper, compared to other heavy metals. Overall results suggest that there was no direct relationship between total and bioavailable metal concentration, although zinc, copper and cadmium show some relationships.

• Journal of the Korean earth science society
• /
• v.43 no.1
• /
• pp.110-118
• /
• 2022

Frequent drought damage has resulted in the polarization of water resources. In Korea, local periodic abnormal droughts continued to occur between 2011 and 2017, resulting in decreased water storage rates of small-scale reservoirs designed with a frequency of 10-year droughts. This decrease can degrade water quality and limit the use of already secured quantities. Therefore, to prepare for and overcome drought, quality management and recalculation of drought frequency are required. This study estimates the potential pollutants causing quality changes in the reservoir. In addition, it reviews the decrease in storage and consequent changes in the quality of a reservoir during drought.

• Journal of the Korean Geotechnical Society
• /
• v.24 no.5
• /
• pp.15-25
• /
• 2008

Contamination level assessment of harbor dredged materials is carried out for beneficial use, which generated annually due to port construction and maintenance of harbor channel. The basic purpose of environmental risk assessment was a scientific approach to susceptibility of hazard risk to human's health from different dredged materials. And this paper proposes a guideline of safely beneficial use of dredged materials at both industrial area and residental area, generated from major port execution throughout a sound investigation of their contamination levels. Newly proposed guidelines were in general higher levels compared to both current guidelines of treatment and use of dredged materials and soil environment protection levels. Finally, environmental assessment results of dredged material contamination generated in major ports of Korea for beneficial use based on pre-assessment environmental levels show that some port's dredged materials contain heavy metals such as Cd, As, Cr and Zn, more than base levels which requires more precise contamination investigation. Others were found to be very appropriate for beneficial use.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.1
• /
• pp.53-57
• /
• 2009

Heavy metal pollution may be one of the most serious challenges confront crop production and human health. Therefore, the selection of heavy metal tolerance cultivars which adapted to the contaminated fields will introduced a suitable solution for management this critical environmental risk. The objectives of this research is to assess human health risk using geochemical analyses and exposure assessment of heavy metals in rice cultivars. Risk for inhabitants in the closed mine area was comparatively assessed for As, Cd, Cu and Pb in 10 rice varieties as a major exposure pathway. The average daily dose (ADD) of each heavy metal was estimated by analyzing the exposure pathways to rice and soil. For the non-carcinogenic risk characterization, Hazard Quotient (HQ) and Hazard Index (HI) were calculated using toxicity indices provided by US-EPA IRIS. The different rice varieties revealed a wide range of HI values from 23.6 to 34.3, indicating that all rice varieties have a high potential toxic risk. The DA rice variety showed the lowest HI value while the TB rice variety the highest. The probabilities of cancer risk for As via rice consumption were varied with rice varieties ranging from 2.0E-03 to 3.5E-03 which exceeded the regulatory acceptable risk of 1 in 10,000 set by US-EPA. The DA rice variety also showed the lowest value while the TB rice variety gave the highest value. Our results indicate that risk assessment can be contribute to screen the pollution safe rice cultivars in paddy fields affected by the mining activity.

• Journal of Food Hygiene and Safety
• /
• v.16 no.4
• /
• pp.324-332
• /
• 2001

Foods constitute a large portion of heavy metal exposure toward general population and attract a deep concern with respect to assuring human health. This study summarized published data in Korea on the content, and dietary intake of heavy metals and assessed their risk potential in comparison with foreign data. An analysis for the yearly fluctuation of metal contents including arsenic, cadmium, mercury and lead by flood group (marine fishes, coastal shellfishes, freshwater fishes, cereal grains) exhibited a decreasing trend from the 1970s to the 1990s. When compared with domestic standards of heavy metals, their mean contents were below the limit and their maximum values seldom exceeded the limit. The data on the dietary intake of heavy metals by Koreans showed a decreasing trend from the 1980s to the 1990s. The average intakes offs and Hg were 6∼8% and those of Cd and Pb were 50∼80% of PTWI(provisional tolerable weekly intake), all of which were below the tolerance. As the extreme intakes of these metals may exceed the PTWI, a careful assessment for them may be necessary. Dietary intakes of Cd, Hg and Pb by Koreans lie in the mid-level among countries cited in the GEMS/Food monitoring data. As fishery foods are suspecious of contamination with Hg, Cd and As, and floods in general are with Pb, it is necessary to establish legal limits for these metals and monitor any progress of their contamination. Furthermore, overall assessment of exposure to heavy metals from all sources including floods, air, drinking water and occupation should be made in order to confirm the dietary risk factors and to assure the safety of food resources.

• Korean Journal of Environmental Agriculture
• /
• v.4 no.2
• /
• pp.88-94
• /
• 1985

In order to investigate the pollution potential of soils after the construction of Onsan Industrial Complex(non-ferrous metal refineries), concentrations of hazardous heavy metals were analyzed for soil samples collected from paddy, upland, orchard and forest soils around the Complex during the period of March 1978 to May 1979. The results are summarized as follows. 1) The concentrations of heavy metals (air-dry basis) for cultivated soil samples from 46 sites were obtained in the range of trace-9.3 ppm As, trace-0.6 ppm Cd, 4${\sim}$22 ppm Cu, trace-0.37 ppm Hg, 6${\sim}$43 ppm Pb and 27${\sim}$93 ppm Zn, which were regarded as non-polluted when compared with the whole Korea data for non-polluted paddy soils. 2) When the heavy metal concentrations were compared with respect to paddy, upland and orchard soils, no significant difference was observed in As, Cd, Cu and Zn whereas significant difference was observed in Hg and Pb. When they were compared with respect to region surrounding the Complex, no significant difference was observed in As, Cd, Hg whereas significant difference was observed in Cu and Pb. 3) Soil samples from several sites near Korea Zinc Refinery were contaminated with Cd, Pb and Zn, due to the accidental emission during its testing operation. Any further contamination was not observed after regular operation of the Refinery.

• Economic and Environmental Geology
• /
• v.53 no.6
• /
• pp.743-753
• /
• 2020

This study analyzed heavy metal concentration, mineral composition, and spectral characteristics of heavy metal contaminated soil samples of cropland and rice field located in downstream of abandoned Okdong coal mine. X-ray fluorescence analysis detected heavy metal elements including cadmium, copper, arsenic, lead, zinc and nickel in the soils. Both cropland and rice field samples were severely contaminated with arsenic showing higher concentration over the concerned standard. The pollution index of cropland samples was higher than that of rice field samples. X-ray powder diffraction analysis identified that the mineral composition of cropland and rice field samples is similar with quartz, calcite, kaolinite, illite, smectite, magnetite and hematite. The range of organic matter content were more widely distributed in cropland samples. The spectral analysis showed that the reflectance spectra and the absorption features of cropland and rice field samples were alike. The absorption features that appeared near 490nm and 900nm were attributed to the ferric iron, and clay minerals such as kaolinite and smectite caused the absorption features at 1410nm, 1910nm and 2200nm. The reflectance of the soil spectral decreased with an increase in organic content. The absorption depths of both types of soil samples decreased with higher organic matter content at 490nm and 1916nm as well as higher heavy metal concentration.

• Journal of Soil and Groundwater Environment
• /
• v.22 no.5
• /
• pp.89-97
• /
• 2017

In this study, we evaluated effect of particle size on arsenic solid-state speciation and bioaccessibility in soils highly contaminated with arsenic from smelting and mining. Soils were partitioned into six particle size fractions ($2000-500{\mu}m$, $500-250{\mu}m$, $250-150{\mu}m$, $150-75{\mu}m$, $75-38{\mu}m$, <$38{\mu}m$), and arsenic solid-state speciation and bioaccessibility were characterized in each particle size fraction. Arsenic solid-state speciation was characterized via sequential extraction and XRD analysis, and arsenic bioaccessibility was evaluated by SBRC (Solubility Bioaccessibility Research Consortium) method. In smelter site soil, arsenic was mainly present as arsenic bound to amorphous iron oxides. Fine particle size fractions showed higher arsenic concentration, but lower arsenic bioaccessibility. On the other hand, arsenic in mine site soil showed highest concentration in largest particle size fraction ($2000-500{\mu}m$), while higher bioaccessibility was observed in smaller particle size fractions. Arsenic in mine site soil was mainly present as arsenolite ($As_2O_3$) phase, which seemed to affect the distribution of arsenic and arsenic bioaccessibility in different particle size fractions of the mine soil.

• Journal of Korea Soil Environment Society
• /
• v.5 no.2
• /
• pp.13-21
• /
• 2000

Detention basin is the temporary holding pond of treated water prior to flow out to the sea. It is very common to dredge the soil from the bottom of detention basin to keep up the water holding capacity. In this study, the amount of volume reduction of dredged soil from detention basin was estimated based on the laboratory test results. The percentage of soil particles in dredged organic soil is about 12.5∼21.9% by weight. The content of heavy metal and environmental effect for dredged soil itself and solidified dredged soil were analysed and the results are meet the standards of environmental requirement.