• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.153-161
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• 2002

The installation of subsurface drainage equipment is required for generalized use of paddy field and to improve soil productivity. The internal drainage of paddy field has improved root condition from the increasing of oxygen supply and removing noxious elements. This experiment was carried out to determine the effects of fertilization and drainage system on soil characteristic, growth and lodging trait of rice in paddy soil. A subsurface drainage system was installed a depth of 0.8m. Three fertilizer treatments were applied : 1) Conventional fertilized plot, 2) Controlled-release fertilized plot, 3) No-fertilized plot. In conventional plot, 110 kg N (as urea 46%), 45 kg P (as fused phosphate 20%) and 57 kg K (as potassium chloride 60%) per hectare fertilizers were applied. Controlled-release fertilizer was applied by 70% of N compared to the conventional plot. During the rice cropping, the water depth decrease was two times higher in subsurface drainage(SD) plot than non-drained(ND) plot. After harvesting of rice, the bulk density of sub-soil(10-20cm depth) was lower in SD plot than ND plot. After the experiment, the surface soil pH was high at SD plot but sub-soil was high at ND plot. Organic matter content was higher in all soil layer for SD plot than fro ND plot. Available $P_2O_5$ was not different between SD and ND plot for surface soil, but was high for SD plot for sub soil. The $NH_4{^+}-N$ content of soil, shoot dry matter, total nitrogen and $K_2O$ of rice plant were greater after panicle formation stage in SD plot. Total nitrogen content, $P_2O_5$ and $K_2O$ of rice root were high in SD plot after heading. Though the gravity center and 3rd internode length were greater, pulling force of rice root was higher in SD plot than ND plot. Rice yield in SD plot were low at conventional and controlled-release fertilized plot because of the greater field lodging, but yield in SD plot was high at no-fertilized plot. This study indicates that the fertilization level should be decrease on subsurface drainage system for rice cropping.

• Economic and Environmental Geology
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• v.30 no.3
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• pp.209-222
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• 1997

The Hoenam area, up the Taecheong lake, composed mainly of low grade coal-bearing metapelites within the Ogcheon Supergroup. These coal formations are developed discontinuously several hundred meters and swelling from 10 to 300 cm along the host metapelites. Although the formations have been mined for coal, but already mined out, and the formations were higher content (mean value of 42 samples) of environmental toxic elements as As (13 ppm). Ba (1.81 wt. %), Cd (2 ppm), Cr (188 ppm), Cu (87 ppm), Mo (214 ppm), Pb (25 ppm), Sb (3 ppm), Se (12 ppm), U (55 ppm), V (2124 ppm) and Zn (234 ppm) than the host metapelites and the NASC. The Al, Ti, Mg, K and Na contents in stream sediments derived from the Hando and Bugook mine area were highly concentrations than the samples from the Samseongjeil mine area. The mean value (wt. %) of Fe (10.07), Mn (0.15), Ca (0.84), P (0.18) and Ba (0.77) influenced by the Samseongjeil mine were higher than the other mine drainage sediments. The mean content (ppm) of environmental toxic elements in drainage sediments from the Samseongjeil mine were taken As (2083), Cu (447), Mo (202), Ni (720), Pb (42), U (250), V (1070) and Zn (2632), which are extremely high concentrations against NASC and EPA. Characteristics of elemental behavior and dispersion of the all toxic elements are the same as increased with increasing U, V, and Cu. Rare earth elements in the sediments are enriched with LREE (La, Ce and Nd) from the drainage on strong concentration of toxic elements. The pH of stream water is neutral, but pH of the sediments ranged from 4.92 to 6.93 (mean 6.22), those are slightly acid in the Hando mine area. Major elements in the host rocks at the Hoenam area are mostly depleted especially Ca, excepting Ti and Ba, normalized with NASC. The sediments were highly enriched of Ti, Fe, Mg, Mn and Ba, but depleted of Al, K, Ca, Na and P on the basis of host rocks and NASC. Minor and environmental toxic elements in the host rocks were strongly enriched all elements (As, Cd, Mo, Se, D, V and Zn), excepting Co, Ni and Sr. Enrichment index (mean value) about toxic elements (As, Cr, Cu, Fe, Ni, Pb and Zn) of the sediments in this area have taken 41.35 (Hando mine drainage; 2.73, Samseongjeil mine drainage; 113.14 and Bugook mine drainage; 8.19), those are seriously contaminated by environmental toxic elements.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.63-75
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• 1999

This study was performed to investigate applicabilities of sewage sludge and papermill sludge as carbon sources in biologically treating abandoned acidic mine drainage, and effects of limestone. In spite of ranging average 3.3 in influent pH, SRB(Sulfate Reducing Bacteria) was well grown. because effluent pH was maintained by alkalinity a little under for whole stages. TCODcr was high in effluent with washing out in early stage. but its concentration was low with passed time and did not cause the problem of secondary pollution. Removal rate of Mn was remarkably low, but in case of heavy metals such as Fe, the fixation trends showed high as the volume of ${SO_4}^2$ reduction increased. In case of mixing sewage sludge and papermill sludge, when their mixing ratio were 1 : 1 and 2 : 1 respectively, rate of ${SO_4}^2$ reduction and removal rate of heavy metals were high. The mixing ratio 1 : 1 was considered as the most appropriate, because degradability of swewage sludge under short time was higher than that of papermill sludge. As a result of investigating efficiencies of limestone and biological treatment, biological treatment excelled limestone in neutralization and removal rate of heavy metals.

• Economic and Environmental Geology
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• v.42 no.3
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• pp.207-216
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• 2009

In this study, water quality variation in borehole groundwaters and surface leachate waters were investigated on a seasonal sampling and remote monitoring basis within the waste impoundments at the Geopung mine site where previous rehabilitation measures were unsuccessful to prevent acidic drainage. All groundwaters were typical acidic drainage with acidic pH (3.3${\sim}$4.6) and high TDS (338${\sim}$3330 mg/L) values during the dry season, but increases in metal contents (TDS 414${\sim}$4890 mg/L) and decrease of pH (2.7${\sim}$3.6) were observed during the rainy season. Surface leachate waters showed a similar pattern in water quality variation. Surface runoff waters during rain events had acidic pH (3.0${\sim}$3.4) through direct reactions with waste rocks. Good correlations were found between major and trace elements measured in water samples, but no significant seasonal variation in chemical compositions was shown except relative changes in contents. It can be suggested that dissolution of soluble secondary salts caused by flushing of weathered waste rocks and tailings directly influenced the water quality within the waste impoundments. Increases in acid and metal concentrations and their loadings from mine wastes are anticipated in the rainy season. More appropriate cover systems on waste rocks and tailings necessitate consideration of more extreme conditions in the study mine.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.328-336
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• 2008

Metal mining district drainage is a well recognized source of environmental contamination. Oxidation of metal sulfides produces acidic and metal-rich waters that contaminate local surface water and ground water in mines, mine dumps, and tailing impoundments. This monitoring study was carried out to investigate the stream water quality and pollution as affected by the Sambo mine drainage in relation to the relative distance from the mine. It obvious that pH values of the mine drainage ranged from 5.8 to 6.9, while the average concentrations of the dissolved chemical constituents for EC, $SO_4^{2-}$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were $1.77\;dS\;m^{-1}$, 929, 14.6, 263.3, and 46.9 mg/L in mine drainage discharged from the main waste rock dumps (WRD), respectively. Furthermore, EC values and sulfate concentrations exceeded the critical toxicity levels in agricultural water for rice plant ($1.0\;dS\;m^{-1}$ for EC and 54.0 mg/L for $SO_4^{2-}$). Also, the average of dissolved cadmium concentrations ($0.016{\sim}0.021\;mg/L$) was higher than water quality standard (0.01 mg/L) for agricultural water in Korea, in addition to Zn, Fe and Mn were higher than trace metals maximum concentrations which recommended by FAO for irrigation water. The results indicate that mine drainage discharged from the Sambo mine affected stream water at least to distance of 1 km downstream of the mine water discharge point. EC values, $SO_4^{2-}$ and $Ca^{2+}$ concentrations in discharged water positively correlated with dissolved Cd, Zn, Al and Mn concentrations, while the pH values negatively correlated. In addition, EC values, $SO_4^{2-}$ and $Ca^{2+}$ concentrations were negatively correlated with pH values.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.100-101
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• 2004

Many researches in Korea have been performed to understand the pollution of stream waters by acid mine drainage. However, few studies have been conducted regarding the effect of particulate and colloidal fractions on the transport of trace metals. To estimate harmful effects of trace metals, it is important to evaluate the particulate and colloidal metals as well as dissolved metals, because particulate and colloidal fractions of trace metals play an important role in transport of trace metals and may adversely affect habitats and organisms in riverine system. Colloids are solids with effective diameters in size range from 0.001 $\mu$m to 1 $\mu$m. According to Jone et al. (1974), metals in surface water, like Al, Fe, and Mn, require filtration with pore-size membranes smaller than 0.45 $\mu$m to define dissolved concentrations. The main objective of this study is to understand the effects of particulate, colloidal, and truly dissolved fractions on the transport and fate of trace metals in acid mine drainage. This study was conducted for the Onjeong creek in the Uljin mine area. Sampling was carried out in 13 sites, spatially covering the area from mine dumps to the downstream Onjeong reservoir. To examine the metal partitioning between particulate, colloidal, and truly dissolved fraction, we used successive filtration techniques consisting of conventional method (using 0.45 $\mu$m membranes) and tangential-flow ultrafiltration (using 0.001 $\mu$mm membranes). Ultrafiltration may seperate much smaller particles from aqueous phase (Josephson, 1984; Hernandez and Stallard, 1988). The analysis of metals were performed by inductively coupled plasma - atomic emission spectrometer (ICP-AES: model Perkin Elmer OPTIMA3000XL). Anions such as SO$_4$, Cl and NO$_3$ were measured with ion chromatograph (IC: model Dionex 120). Sample analysis is still in progress. The preliminary data show that the studied creek is severely polluted by Al, Fe, Mn, Pb and Zn. Toward upstream sites with relatively lower pH, less than 50% of Al and Fe occur in the sorbed form on particles or colloids, whereas more than 80% of Al and Fe occur in the sorbed form in downstream sites or tributaries with relatively higher pH. Less than 30% of Zn is present in particle or colloidal forms in the whole range of creek. Truly dissolved fraction of trace metals is negatively correlated with pH. The Kd values for Al, Fe and Zn consistently increase with increasing pH and decrease with increasing particle concentration.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.9 no.1
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• pp.30-35
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• 2013

The four principles of treatment of odontogenic infection are as follows : (1) removal of the cause, (2) establishment of drainage, (3) institution of antibiotic therapy, and (4) provision of supportive care, including proper rest and nutrition. A separate incision is required to establish drainage, especially in the case of extensive fascial space infections. There are four principle causes for active bleeding in the immediate incision & drainage phase; (1) vascular wall alteration (infection, scurvy, chemicals), (2) disorder of platelet function, (3) thrombocytopenic purpuras, (4) disorders of coagulation (liver disease, anticoagulation drug). If the hemorrhage from incision & drainage site is aggressive, the site must be packed with proper wet gauze and wound closure & drainage dressing are applied. The specific causes of bleeding may be associated with hypoxia, changes in the pH of blood & chemical changes affecting vascular contractility and blood clotting. This is a case report of bleeding control by the circumferential suture & drainage on active bleeding incision & drainage site of temporal space abscess due to advanced odontogenic infection in a multiple medically compromised disabled patient.

• Economic and Environmental Geology
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• v.53 no.6
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• pp.667-675
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• 2020

An Alum-sludge based adsorbent (ASBA) was synthesized by the hydrothermal treatment of alum sludge obtained from settling basin in water treatment plant. ASBA was applied to remove fluoride and arsenic in artificially-contaminated aqueous solutions and mine drainage. The mineralogical crystal structure, composition, and specific surface area of ASBA were identified. The result revealed that ASBA has irregular pores and a specific surface area of 87.25 ㎡ g-1 on its surface, which is advantageous for quick and facile adsorption. The main mineral components of the adsorbent were found to be quartz(SiO2), montmorillonite((Al,Mg)2Si4O10(OH)2·4H2O) and albite(NaAlSi3O8). The effects of pH, reaction time, initial concentration, and temperature on removal of fluoride and arsenic were examined. The results of the experiments showed that, the adsorbed amount of fluoride and arsenic gradually decreased with increasing pH. Based on the results of kinetic and isotherm experiments, the maximum adsorption capacity of fluoride and arsenic were 7.6 and 5.6 mg g-1, respectively. Developed models of fluoride and arsenic were suitable for the Langmuir and Freundlich models. Moreover, As for fluoride and arsenic, the increase rate of adsorption concentration decreased after 8 and 12 hr, respectively, after the start of the reaction. Also, the thermodynamic data showed that the amount of fluoride and arsenic adsorbed onto ASBA increased with increasing temperature from 25℃ to 35℃, indicating that the adsorption was endothermic and non-spontaneous reaction. As a result of regeneration experiments, ASBA can be regenerated by 1N of NaOH. In the actual mine drainage experiment, it was found that it has relatively high removal rates of 77% and 69%. The experimental results show ASBA is effective as an adsorbent for removal fluoride and arsenic from mine drainage, which has a small flow rate and acid/neutral pH environment.

• Journal of Korean Neurosurgical Society
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• v.60 no.1
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• pp.1-7
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• 2017

Objective : The diagnosis of shunt malfunction can be challenging since neuroimaging results are not always correlated with clinical outcomes. The purpose of this study was to evaluate the efficacy of a simple, minimally invasive cerebrospinal fluid (CSF) lumbar tapping test that predicts shunt under-drainage in hydrocephalus patients. Methods : We retrospectively reviewed the clinical and radiological features of 48 patients who underwent routine CSF lumbar tapping after ventriculoperitoneal shunt (VPS) operation using a programmable shunting device. We compared shunt valve opening pressure and CSF lumbar tapping pressure to check under-drainage. Results : The mean pressure difference between valve opening pressure and CSF lumbar tapping pressure of all patients were $2.21{\pm}24.57mmH_2O$. The frequency of CSF lumbar tapping was $2.06{\pm}1.26times$. Eighty five times lumbar tapping of 41 patients showed that their VPS function was normal which was consistent with clinical improvement and decreased ventricle size on computed tomography scan. The mean pressure difference in these patients was $-3.69{\pm}19.20mmH_2O$. The mean frequency of CSF lumbar tapping was $2.07{\pm}1.25times$. Fourteen cases of 10 patients revealed suspected VPS malfunction which were consistent with radiological results and clinical symptoms, defined as changes in ventricle size and no clinical improvement. The mean pressure difference was $38.07{\pm}23.58mmH_2O$. The mean frequency of CSF lumbar tapping was $1.44{\pm}1.01times$. Pressure difference greater than $35mmH_2O$ was shown in 2.35% of the normal VPS function group (2 of 85) whereas it was shown in 64.29% of the suspected VPS malfunction group (9 of 14). The difference was statistically significant (p=0.000001). Among 10 patients with under-drainage, 5 patients underwent shunt revision. The causes of the shunt malfunction included 3 cases of proximal occlusion and 2 cases of distal obstruction and valve malfunction. Conclusion : Under-drainage of CSF should be suspected if CSF lumbar tapping pressure is $35mmH_2O$ higher than the valve opening pressure and shunt malfunction evaluation or adjustment of the valve opening pressure should be made.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.26-32
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• 2000

The impact of major surface chemical properties of silica sols on the retention and drainage performance of the silica based micrparticle system, Compozil was investigated using four different silica sols. And the effect of silica properties on the interactions with cationic starch and cationic plyacrylamide has also been identified. The surface charge density and the stability over pH of silica sols were increased by introducing aluminosilicate anions at surface. It was found that the charge density of silica sols determined the addition level necessary to attain the maximum retention and drainage. When silica sols were combined with cationic starch, the change density of the product was the critical properties and the degree of microagregation was of minor importance. In the cationic polyacrylamide system the degree of colloid structure appeared to be a more critcial property than the charge density of silica sols.