• Economic and Environmental Geology
• /
• v.43 no.1
• /
• pp.21-31
• /
• 2010

Mine and leachate waters were collected from the Okdong mine for study on reaction with oxidizing agents such as NaOCl and $H_2O_2$. The pH and EC of the mine and leachate waters are 5.77, 831 uS/cm, and 6.38, 1920 uS/cm, respectively. The concentrations of Mg, Mn, and Zn are 23.25 mg/l, 14.90 mg/l, and 22.99 mg/l for the mine water and 98.75 mg/l, 3.38 mg/l, and 6.16 mg/l for the leachate water. The concentrations of Mg, Mn and Zn decreased after the reaction with the oxidizing agents and mine water. The concentrations of Mg, Mn and Zn rapidly decreased when oxidizing agents increased. The saturation indices that were computed by visual MINTEQ for initial mine and leachate water were undersaturated with Mg, Zn and Mn compounds. The precipitates after the reaction with the oxidizing agents are composed mainly of mangano-calcite[(Mn, Ca)$CO_3$] with small amount of calcite-magnesian and calcite.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.7 no.4
• /
• pp.41-50
• /
• 1987

The present study was conducted to measure and predict the leachate generation and to establish the methods of leachate control and handling by both field and lab-lysimeter studies. The change of biodegradable matter, field capacity, dry density, quantity and quality of leachate as a function of time of landilling were measured. The model based on the theory of unsaturated flow and contaminant transport in porous media was developed and simulation model was used for the prediction of movement of landfill moisture and for the strength in leachate in terms of organic and inorganic contaminant. The model constructed from the present study in terms of unsaturated decomposition and transport combined with the evapotranspiration and surface runoff showed good agreement with the results obtained by lysimeter studies.

• Journal of Korean Society of Water and Wastewater
• /
• v.31 no.3
• /
• pp.219-228
• /
• 2017

Burial sites are constructed for the purpose of controlling air-born livestock diseases such as avian influenza and foot-and-mouth outbreak. As most of the burial sites are located in the agricultural land use, public concerns are mounting about soil and groundwater contamination. During precipitation events, contaminated baseflows are released from the burial sites into surface waters. Baseflow are therefore required to be managed properly, by monitoring and even by remediation means. We propose each burial sites should be regarded as a point source possibly degrade groundwater, thus be managed in watershed scale for the purpose of surface water quality conservation.

• Journal of the Korean Society of Groundwater Environment
• /
• v.1 no.2
• /
• pp.85-89
• /
• 1994

Groundwater and soil contamination by the leak of leachates from the waste disposal site (WDS) is one of the serious environmental problems, and leachates are generally produced by the biogeochmical decomposition and/or precipitation in the WDS. At the Sindae-dong waste disposal site in Taejon, the average Cu, Pb and Zn concentrations in the surrounding soils are higher than those in other Korean soils but these are not high enough to cause any harmful effect to man through the crop plants. Copper, Pb and Zn are not detected in the groundwater samples but the pH of the sample is 5.6 which is not suitable for the drinking water. In contaminated soil samples, the heavy metal concentrations are higher in subsurface soil than in surface soil and it may be influenced by the leachates in groundwater. With the electric resistivity method, the water contains layers are found in contaminated soils and the resistivity values are considerably low because of the dispersion of plume by the leak of leachates. According to the distance from the leak point of leachate, resistivity values increased and heavy metal concentraions in soils decreased due to the reduction of plume.

• The Journal of Engineering Geology
• /
• v.22 no.4
• /
• pp.409-416
• /
• 2012

In this study, an electrical resistivity survey and a drilling investigation were conducted at an animal carcass disposal site. Chemical analysis of leachate collected from the site was also performed (sampling times: May 2011 and June 2012). Five lines of dipole-dipole electrical resistivity surveys were carried out, along with drilling investigations at 3 points within the disposal areas and 11 points near the disposal site. Two-dimensional inverse modeling of the collected resistivity data was performed to evaluate the properties (size, depth, and form) of the disposal site. Leachate analysis showed that pH of leachate decreased from 7.4 to 6.7, while Eh changed from -358 mV to -48 mV over time. In addition, dissolved ions increased due to the progression of carcass decomposition. Results of the electrical resistivity survey indicated that low resistivity zones (minimum value, $0.64{\Omega}m$) existed at a depth of 8 m from the surface. Considering the bedrock location and carcass disposal depth, there was no evidence of bedrock contamination by leachate. The results of the electrical resistivity survey are consistent with those of the drilling investigation, which indicates that electrical resistivity effectively depicted the properties of the disposal site. This study demonstrates that electrical resistivity survey is a suitable technique for investigation of animal carcass disposal sites.

• Journal of the Korean Geotechnical Society
• /
• v.17 no.6
• /
• pp.47-51
• /
• 2001

There are two strategies to cope with the troubles in landfill site after closure. The first method is active in a way that the wastes are dug up and the recyclable materials are reutilized, meanwhile the materials not recyclable are incinerated in order to minimize the volume of residues to be disposed of. The second method is rather passive and defensive in a way that the source of contamination, that is, buried wastes are not treated. Instead, the transport of leaking leachate and gases generated from the wastes are intercepted and controlled. In this study, as a passive way of the efficient leachate blocking process, applicabilities of geocrete and soluble sodium silicate as a substitute to control leachate leaking from landfill sidewall were investigated. In case of compression test, the strength of mixture I (Geocrete:Sodium silicate=1:3.9 v/v) and mixture II (Geocrete:Sodium silicate=1:2.5 v/v), even after 7 days' curing was higher than the minimum allowance to tolerate the loading(5 kg/$\textrm{cm}^2$). Soaking in the acid fur 4 days and 7 days respectively, the compressive strength of the specimens reduced seriously. The toxicity of geocrete is not detected through the bioassay test, once it was mixed with sodium silicate and the complex was formed. The hydraulic conductivity of the mixtures even after 7 days' curing was lower than the threshold limit $(1.0\times10_{-7}cm/s)$.

• Journal of Korean Society of Forest Science
• /
• v.96 no.3
• /
• pp.369-375
• /
• 2007

We examined two Populus species (Populus euramericana and Populus alba ${\times}$ Populus glandulosa) trees grown under livestock waste leachate treatment in the field. We investigated their physiological properties (photosynthetic rate, chlorophyll contents, transpiration rate and intercellular $CO_2$ concentration) and antioxidant enzyme activities. Ascorbate peroxidase and glutathione reductase were analyzed. According to our measurements, P. euramericana at control site showed a lower total chlorophyll contents, photosynthetic rate, intercellular $CO_2$ concentration, transpiration and stomatal conductance than those of trees at treatment site. P. alba ${\times}$ P. glandulosa showed low stomatal conductance and low photosynthetic rate.

• Journal of the Mineralogical Society of Korea
• /
• v.27 no.3
• /
• pp.125-134
• /
• 2014

The Janggun mine (Longitude $E129^{\circ}$ 03' 40", Latitude $N36^{\circ}$ 51' 19") was once operated as an underground mine and recently significant amount of mine and leachate water has been discharged from the mine adits and tailing dumps. Mine and leachate waters are characterized by neutral to weakly basic pH values (6.81-9.59). Major cations and anions have concentrations between 6.70-129.80 mg/L of Mg, 289.29-661.02 mg/L of Ca, 4.74-14.38 mg/L of Mn and 1205.00-2448.69 mg/L of $SO{_4}^{2-}$. Brownish yellow precipitates that found in the stream bottom consist of poorly crystallized 2-line ferrihydrite ($Fe_2O_3{\cdot}0.5H_2O$. Scanning electron microscope (SEM) photographs show that brownish yellow precipitates consisted of micro-sized granular particles of about $0.1{\mu}m$ in diameter. Semi-quantitative energy dispersive spectrometry (EDS) analyses show that these samples contained mainly Fe with minor Mn, Ca, Si and As.

• Journal of the Korean GEO-environmental Society
• /
• v.18 no.9
• /
• pp.5-9
• /
• 2017

On the flow of groundwater, the effect of consecutive column-wall in underground as a hydraulic barrier could be identified by conventional geotechnical methods ((1)visualiy identification of wall mass after underground excavating, (2)uniaxial compressive strength test for core of wall mass in underground, (3)in-situ permeability test in the hole after coring wall mass). However, for the cut off the leakage or infiltration of very high concentrated leachate from the waste landfill or the contaminated groundwater, the waterproof effect of consecutive column-wall in underground should be verified more objectively, by in-situ measuring of pH, temperature and salinity. and by evaluating of their consistency and similarity throughout analyzing the characteristics of basic components and their profiles through the series of chemical experiments. Furthermore, its waterproof effect could be verified additionally throughout deciding the similarity more simply by comparing the general distribution patterns including the difference of high and low peaks from the chromatograms using GC-MS for surrounding groundwater.

• International Journal of Highway Engineering
• /
• v.13 no.2
• /
• pp.187-193
• /
• 2011

The stormwater runoff from road or expressway is known as one of important nonpoint pollution sources. To reduce the pollutants discharge from road or expressway, many best management practices(BMPs) have been applied and planned. Among the BMPs, road sweeping can be effective way to prevent pollutant washoff to environment. This study is performed to evaluate the characteristics of particles collected from the road by sweeping car. Size distribution and pollutant concentration of particles were analyzed. Based on the pollutant concentration and the specification of road such as length, width, and unit for pollutant generation, total amount of pollutant to be removed by road sweeping was estimated. Most of sediments collected by road sweeping was classified into sandy soil and fraction of fine grained soil was low. Although the concentrations of pollutants such as heavy metals in road sediments did not exceed the soil contamination criteria, washout of pollutants during sweeping work by spraying water might cause leaching of pollutants contained in sediments and thus resulted in low pollutant concentrations. Reduced amounts of pollutant by road sweeping showed 31.4% TSS reduction for ${\bigcirc}{\bigcirc}$ region and 7.7% TSS for ${\triangle}{\triangle}$ region. Other pollutants showed low reduction rate, because of their leaching by water spraying. Results from this study indicate that detailed and well-planned investigation for the road sweeping is necessary for the accurate estimation of pollutant reduction from road or expressway.