• Journal of the Korean Geotechnical Society
• /
• v.18 no.6
• /
• pp.103-116
• /
• 2002

The development of contaminated sites often requires foundation concrete to be placed in contact with soils contaminated with organic compounds. There is a common perception that organic compounds affect the setting and hardening of concrete, giving a reduced long-term strength. In this study, unconfined compressive strength tests for concrete cured in Ethylbenzene were performed. The possibility of byproduct to be used for aggregate of concretes as materials of construction was also evaluated by carring out the investigation of the characteristics of the mixture of concrete and crushed oyster shell which is treated as waste material and often illegally disposed at coastal oyster production site. The transformation of strength characteristics was investigated by varying the blending ratio of fly ash.

• Journal of Biosystems Engineering
• /
• v.33 no.6
• /
• pp.404-409
• /
• 2008

Excessive presence of heavy metals in environment affects plants and fruits grown in the contaminated area. Rapid on-site monitoring of heavy metals can provide useful information for efficiently characterizing heavy metal-contaminated sites and for minimizing the exposure of the contaminated food crops to humans. This study reports on the evaluation of gold and glassy carbon (GC) electrodes with mercury or bismuth as a coating material for simultaneous determination of cadmium (Cd) and lead (Pb) in 0.1 M $HNO_3$ solution by anodic stripping voltammetry (ASV). The use of a square-wave voltammetric potential between a working electrode and a reference electrode caused Cd and Pb ions deposited on the electrode surface to be oxidized, thereby generating electric currents at different potentials. The mercury-coated gold electrode was not sensitive enough to detect the usable range of Cd concentrations (1 to 100 ppb). The GC electrodes with mercury or bismuth displayed well-defined, sharp and separate current peaks for Cd and Pb ions when the square-wave voltammetric potentials were applied. The peak currents measured with both mercury- and bismuth- coated GC electrodes were linearly proportional to Cd and Pb concentrations in the range of 1 to 200 ppb in 0.1 M $HNO_3$ with strong linear relationships between concentration and peak current ($R^2$ > 0.95), indicating that both of Cd and Pb ions could be quantitatively measured.

• Economic and Environmental Geology
• /
• v.37 no.1
• /
• pp.49-59
• /
• 2004

The concectration and distribution of contaminants obtained from a contaminated land investigation or an environmental geochemistry survey constitutes the basis of a decision-making process on environmental policies or of scientific researches. As the quality of data determines the reliability of the result, the investigation plan should be adjusted according to the purpose of the investigation. In general, the effort to improve the data quality had been focused mainly on the QA/QC procedures in laboratories. The rapid progress of analytical instrument has also contributed toward improving the analytical precision to a sacrificable degree. Nevertheless, in many cases, it is not the analytical precision that needs improvement for the better precision of overall measurement process: it is rather during the sampling process in the field that is responsible for the poor precision. To assess the data quality on a measured value, ISO recommends to provide information on "measurement uncertainty" along with the measured value. The measurement uncertainty in an environmental measurement context can be explained as the statistical number that expresses the degree of the uncertainty stemming from the sampling and analytical procedures. There is a cost involved in order to improve the precision of sampling and analytical methods so as to decrease the degree of measurement uncertainty. The economical point of compromise in an investigation planning can be achieved when the allowable degree of uncertainty has been set before-hand. The investigation can then be planned accordingly not to exceed the uncertainty limit. Furthermore, if the measurement uncertainty estimated from the preliminary investigation can be separated into sampling and analytical uncertainties, it can be used as a criterion where the resources for the investigation should be allotted cost-effectively to reinforce the weakest link of the whole investigation process. This paper aims to present a method of estimating the level of measurement uncertainty of a measured contamination concentration at a site used as an example and to show how the estimated uncertainty can be applied to serve the particular purpose of an investigation.

• Korean Journal of Environmental Agriculture
• /
• v.28 no.4
• /
• pp.378-385
• /
• 2009

Arsenic (As) is known to be very toxic and carcinogenic to human beings. Arsenic contaminated soil was collected from a timber mill site at Busan Metropolitan City, Korea, where chromated copper arsenate (CCA) had been used to protect wood from rotting caused by insects and microbial agents. The soil was stabilized using both natural oyster shells (NOS) and calcinated oyster shells (POS). The calcination of natural oyster shells was accomplished at a high temperature in order to activate quicklime from calcite. Two different oyster shell particle sizes (-#10 mesh and -#20 mesh) and curing periods of up to 28 days were investigated. The stabilization effectiveness was evaluated based on the Korean Standard Test (KST) method (1N HCl extraction). The stabilization results showed that the POS treatment was more effective than the NOS treatment at immobilizing the As in the contaminated soils. A significant As reduction (96%) was attained upon a POS treatment at 20 wt% and passed the Korean warning standard of 20 mg/kg ('Na' area). However, an As reduction of only 47% (169 mg/kg) was achieved upon a NOS treatment at 20 wt%. The -#20 mesh oyster shells seem to perform better than the -#10 materials. The scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results showed that As immobilization was strongly associated with Ca and O in the presence of Al and Si.

• Tribology and Lubricants
• /
• v.33 no.6
• /
• pp.263-268
• /
• 2017

The significance of maintaining the soil environment is gradually increasing owing to soil and underground water contamination by petroleum leak accidents. However, the purification of soil is an expensive and more time-consuming process than the purification of contaminated water and air. Moreover, determining the source and people responsible for soil pollution gets often embroiled in legal conflicts, further delaying the cleanup process of the contaminate site. Generally, TPH (total petroleum hydrocarbon) pattern analysis is used to determine the petroleum species and polluter responsible for soil contamination. However, this process has limited application for petroleum products with a similar TPH pattern. In this study, we analyze the TPH pattern and specific sectional ratio (${\sim}C_{10}$, $C_{10}-C_{12}$, $C_{12}-C_{36}$, and $C_{36}{\sim}$) of various domestic petroleum products to identify the petroleum product responsible for soil contamination. Also, we perform BTEX (benzene, toluene, ethyl benzene, xylene) quantitative analysis and determine B:T:E:X ratio using GC-MS. The results show that gasoline grade 1 and 2 have a similar TPH pattern but different BTEX values and ratios. This means that BTEX analysis can be used as a new method to purify soil pollution. This complementary TPH and BTEX method proposed in this study can be used to identify the petroleum species and polluters present in the contaminated soil.

• Journal of Korean Society on Water Environment
• /
• v.24 no.1
• /
• pp.19-29
• /
• 2008

Hot air sparging is a groundwater remediation technique, in which organic contaminants volatilized into hot air from the saturated to vadose zone. In the laboratory diesel (10,000 mg TPH/kg) was spiked in contaminated saturated aquifer soil. The hot air ($34.9{\pm}2.7^{\circ}C$) was injected in intermittent (Q=1,500 mL/min, 10 minute injection and 10 minute idle) modes. We performed microcosm tests using the groundwater samples to assess TPH reductive remediation activity. For Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis of eubacterial communities in sludge of wastewater treatment plants and soil of experiment site, the 16S rDNA was amplified by Polymerase Chain Reaction (PCR) from the sludge and the soil. The obtained 16S rDNA fragments were digested with Msp I and separated by electrophoresis gel. We found various sequence types for hot air sparging experiment with sludge soil samples that were closely related to Bacillus (149 bp, Firmicutes), Methlobacterium (149 bp, Euryarchaeotes), Pseudomonas (492 bp, ${\gamma}$-Proteobacteria), etc., in the clone library. In this study we find that TPH-water was reduced to 78.9% of the initial value in this experiment aquifer. The results of the present study suggests that T-RFLP method may be applied as a useful tool for the monitoring in the TPH contaminated soil fate of microorganisms in natural microbial community.

• Korean Journal of Soil Science and Fertilizer
• /
• v.48 no.1
• /
• pp.64-71
• /
• 2015

Soil contamination with arsenic and heavy metals is a worldwide problem. Main objective of this research was to evaluated effects of reducing heavy metal leaching under reduced soil condition amended with industrial by-products. The contaminated soil was amended with 3% (w/w) of limestone (Ls), steel slag (SS) and acid mine drainage sludge (AMDS). Synthetic acid rain ($H_2SO_4:HNO_3=6:4$, pH 5.5 fixed) was used for feeding solution with flow rate of $0.78{\sim}0.88mL\;min^{-1}$. Results showed that similar pH and EC of leachate was observed in all treatments regardless of applied industrial by-products. However, arsenic concentration of leachate increased when industrial by-products were mixed. Meanwhile, concentration of heavy metal in the leachate decreased from 11.3 to 4.59 mg for Cd, from 92.3 to 7.93 mg for Pb, and from 11,716 to 1,788 mg for Zn via immobilization in soil with AMDS amended, respectively. Overall, application of industrial by-products can be an environmentally-friendly way to remediate soil and(or) leachate contaminated with metal(loid)s in metal mine site.

• The Korean Journal of Ecology
• /
• v.18 no.3
• /
• pp.419-427
• /
• 1995

This study was carried out to investigate the concentrations of Cu, Pb, Zn and in seawater, sediments and Mytilus edulis at Masan Bay, Onsan Bay, Daesan industrial complex and unpolluted area for the degree of contamination on the coast of Korea. The concentrations of dissolved Cu, Pb, Zn and Cd in seawater the ranges of 0.29~0.79 ${\mu}g/l$, 0.03~0.08 ${\mu}g/l$, 0.19~2.01 ${\mu}g/l$ and 0.01~0.05 ${\mu}g/l$, respectively. The concentrations of Pb(p<0.001) and Zn(p<0.01) showed the significant differences between the contaminated and unpolluted area. There were the ranges of 13~55 ${\mu}g/l$, 26~101 ${\mu}g/l$, 51~263 ${\mu}g/l$ and 0.8~2.2 ${\mu}g/l$ in the concentration of Cu, Pb, Zn and contaminated and unpolluted area. The concentration of Cu, Pb, Zn and Cd in the Mytilus edulis showed the ranges of 0.69~2.77 ${\mu}g/l$, 0.29~1.50 ${\mu}g/l$, 13.57~52.90 ${\mu}g/l$ and 0.09~0.85 ${\mu}g/l$ respectively. These concentrations of four trace metal in Mytilus edulis were not significantly different with sites. Trace metal contents of Mytilus edulis in the contaminated site were similar to those in the unpolluted area. This is thought that metal concentration in coastal seawater were not relatively serious.

• Journal of Korean Society of Environmental Engineers
• /
• v.38 no.7
• /
• pp.377-386
• /
• 2016

The purposes of this research are to examine soil pollution in the nation and to explore the contaminated soil management of the public housing agency in public land for residential development. In so doing, the primary and secondary data were utilized, the former made use of the public data annually released by the Korea Ministry of Environment, and the latter relied on a self-administerd questionnaire survey conducted in the staff of the public housing agency, particularly those in charge of soil contamination in large-scale land, housing and urban development projects. The findings reveal that the national concentrations of 21 inorganic and organic soil contaminants (e.g., Cd, Cu, As, Hg, Pb, Cr, Zn, Ni, F, P, PCB, CN, Phenol, BTEX, TPH, TCE, PCE, Benzo(a)pyrene, and pH) in the land were extracted to be well below the risk level designated by the statutory guidance while industrial areas had them at a relatively modest level. In addition, the survey results indicate that the public housing agency didn't establish specific and clear guidelines for soil pollution and its remediation in the residential land development, so that contaminated sites have been primarily remediated by outsourcing companies. As the unexpected occurrence of contaminated sites causes the incurring expenses added to total project budget, the provision of both professional training and on-site manuals with the sufficient information on techniques and methods of soil contamination is critical to promptly and systematically deal with soil pollution.

• Journal of Korea Soil Environment Society
• /
• v.4 no.1
• /
• pp.3-11
• /
• 1999

The effects of major cations in soils, soil : extractant ratio, and EDTA : lead stoichiometric ratio on the extraction efficiency of lead using EDTA were studied for 4 different actual lead-contaminated soils and one artificially lead-contaminated soil. Extraction of lead from the lead-contaminated soil was not affected by a soil : extractant ratio as low as 1 : 3 but instead was dependent on the quantity of EDTA present. Results of the experiments showed that the extraction efficiency for each soil was different, but if sufficiently large amount of EDTA was applied, all the lead may be extracted except for a soil from lead mining area. The differences in extraction efficiencies nay be due to the major cations present in soils which may compete with lead for active sites on EDTA. The total molar amount of major cations extracted was as muck as 20 times more than the added molar amount of EDTA. For some of the soils tested, the extraction efficiency of lead may be affected by being occluded in the Fe and Mn oxides present in the soil. While major cations present in the soil may be one of the factors affecting lead extraction efficiency, the type of lead species present may also play a role. When these factors affect severely, the using of EDTA to extract lead from lead-contaminated soil might be non-effective method.