• 한국환경과학회지
• /
• 제7권5호
• /
• pp.623-631
• /
• 1998

Pyrite contained in wasted ore dumps induces a strong acid environment when it contacts oxygenated rainfall. Present research was designed to evaluate the pollution of an area that is supposedly contaminated by pyrite of ore wasted dumps form in Chonju Il Mine. Measured are the pH and selected heavy metal elements in the supposedly polluted hydrologic system. The samples include three types : those collected from the stream waters; those from the stream sediments; and those from the rice field soil scattered over the area. The dispersion path of the pollution source was also traced. The pH of the hydrologic system ranged from 3.44 to 5.46, which clearly indicates that the area is on the acid environment. The pH tends to rise as the distance from the minehead increases. The content of heavy metal elements dissolved in the stream water varies as follows; Mn=69.73~1.99ppm, Cd=0.02~0.03ppm, Zn=0.77~1.18ppm, Cu=0.04~0.13ppm, Pb=0.22~0.32ppm. The stream water in this state may induce serious heavy metal pollution to the agricultural land and the water for human life especially in the villages down the stream. The content of heavy metal elements dissolved in the stream sediment varies as follows; Mn=245.0~4685.0ppm, Cd=10.0~15.0ppm, Zn=105.0~210.0ppm, Cu=65.0~155.0ppm, Pb=90.0~150.0ppm. The content of heavy metal elements dissolved in the rice field soil varies as follows; Mn=185.0~260.0ppm, Cd=10.0~15.0ppm, Zn=135.0~180.0ppm, Cu=65.0~90.0ppm, Pb=100.0~130.0ppm. The pollution index in the stream sediment and the rice field sell is 1.36~2.03, which shows that pollution had already begun all over the area where the samples were collected.

• 한국산업보건학회지
• /
• 제22권4호
• /
• pp.284-292
• /
• 2012

Objectives: The objective of this study was to investigate the relations between the bacterial concentration and the environmental factors in the water soluble metal working fluids at factories. Methods: The bacterial concentrations for airborne and fluid samples of 7 factories were quantified during the summer season. And we statistically analysed the relations between the bacterial concentrations and the factors such as temperature, relative humidity, usage quantity, mixing ratio and exchange interval. Results: The geometric mean levels of the airborne bacterial concentrations were 79.1(range : N.D.~686) $CFU/m^{3}$ and 68.1(range: N.D.~919) $CFU/m^{3}$ in the process and outdoor. The airborne bacterial concentrations showed no statistical difference by process, usage quantity, mixing ratio and exchange interval. The airborne bacterial concentrations had negatively weak correlations with air temperature and relative air humidity(p<0.05). The bacterial concentrations and pH showed significantly negative correlations in the fluids(p<0.05). And the airborne bacterial concentrations in factories and those in metal working fluids showed no statistical relationship. Conclusions: In the water soluble metal working fluids using factories, the airborne bacterial concentrations of the process were related to those of the outdoor and environmental factors, rather than the onsite contaminated metal working fluids.

• 대한수의학회지
• /
• 제41권1호
• /
• pp.73-78
• /
• 2001

Yersinia enterocolitica is an inhabitant in the lower intestinal tract of many domestic and wild animals as well as in the nature. Of the several forms of diseases caused by Y. enterocolitica, an acute enteritis, especially in young children, is the most common form. Infection of the bacteria usually occurs through fecal-oral route by contaminated foods or water, especially mountainspring water. Of the domestic animals, swine has been known as one of the most important carrier in the human infection. Based on the knowledge, prevalence of antibody against Y enterocolitica was investigated with swine sera collected from Korea for the survey of Y enterocolitica infection in swine. As the first step of this survey, we analyzed outer membrane protein (OMP) profiles of the representative strains of Y enterocolitica isolated from the feces of piglets and mountainspring water in Korea. Thirty-eight kDa OMP was identified as the common OMP regardless of origin, serotype, or biotype of Y enterocolitica isolates. Presence of antibody specific for 38 kDa OMP of Y enterocolitica in 1,076 swine sera collected from November 1999 to October 2000 was analysed with ELISA. Antibody titer in sows was significantly higher than that in piglets, growing pigs and finishing pigs (p<0.05). Also, there was seasonal difference in the prevalence of antibody against Y enterocolitica. These results would provide the basic knowledge for controlling the Y enterocolitica infection in human as well as swine.

• 한국환경농학회지
• /
• 제25권2호
• /
• pp.157-163
• /
• 2006

Investigation of Cd and Zn availability in four different soils as affected by the interactions of these two heavy metals was conducted using the metal desorption quantity-intensity (Q/I) isotherms. The soils were artificially contaminated with proper concentrations of Cd and Zn as $CdSO_4\;and\;ZnSO_4$ solutions. DTPA (diethylene triamine pentaacetic acid) - extractable and water-extiactable Cd or Zn from the soils were used as $Q_{Cd}\;or\;Q_{Zn}\;and\;I_{Cd}\;or\;I_{Zn}$ factors, respectively. The coefficient of determination for Cd and Zn desorption Q/I linear regression in the soils ranged from 0.947 to 0.999, which indicated that Q and I factors were closely correlated. The buffering capacity of Cd, $BC_{Cd}$, in the soils decreased with increasing Zn treatments, and the $BC_{Cd}$ values were ranged between 205.8 and 2255.6. The decreases of $BC_{Cd}$ values were mainly dependent upon the increases of $I_{Cd}$ factors. However, Zn buffering capacity. $BC_{Zn}$ decreased with increasing Cd treatments in acidic soils, and increased in neutral and calcareous alkaline soils. The $BC_{Cd}$ values were ranged from 143.2 to 6158.0. The values of $BC_{Zn}$ as influenced by the treatments of Cd were also controlled by the solubility of water-extractable Zn, $I_{Zn}$ factor. The solubility of water-extractable Cd and Zn was significantly dependent upon the changes of soil pH that were impacted by the treatment of Zn and Cd, respectively. Also, the availability of Cd was higher than Zn availability in the acidic and neutral soils, but Zn was higher than Cd in the calcareous alkaline soil.

• 공업화학
• /
• 제27권6호
• /
• pp.664-668
• /
• 2016

무단 폐기물 투기로 인해 토양, 지하수, 하천 등 환경오염이 심각해지고 있다. 본 연구에서는 J시에서 발생된 무단 투기 유류를 분석함으로써 어떤 유종인지를 분석하였다. 물, 고형불순물, 유류 혼합물 형태를 전처리하여 균질한 유류성분을 얻은 뒤, 물성분석, 원소분석, 및 가스크로마토그래피를 이용해 분석한 결과, 11.8%의 산소함량, $-6^{\circ}C$의 유동점, 크로마토그램의 패턴 결과 식물성기름으로 판단하였다. 또한 어떤 식물성 기름인지 알기 위해 HPLC를 이용해 구성성분을 분석한 결과, LLO, OOL, POL이 높은 비율로 분석되어졌으며, 이는 대두유가 주성분이면서 다른 식물성기름의 혼합형태인 폐유로 최종 판단하였다. 본 연구를 통해 향후, 불법 투기되는 유류에 대한 유종 구분 및 오염원인자 판단을 위해 활용 가능할 것으로 판단된다.

• 한국수자원학회논문집
• /
• 제31권6호
• /
• pp.685-694
• /
• 1998

지하수질 감시를 위한 관측은 지하수를 사용하는 주변 인구의 보건은 물론이고 궁극적으로는 지하수자원 보전이라는 측면에서 매우 중요하다. 그러나 지하수 수질관측망은 설계부터 운영에 이르기까지 임의적이고, 체계적이기보다는 경험에 의존하거나 과학적이지 못한 방식으로 시행되고 있는 것이 사실이다. 본 연구는 지하수질 관측망의 효율적 배치를 위한 방법론의 현장적용성을 검토하기 위하여 대표적인 설계방법론을 대상으로 비교연구 하였다. 그 결과, 지하수질 관측망의 설계 시에는 관측망 설치의 목적을 명확히 설정하는 것이 중요하며, 현장정보의 확보수준에 따라 선택될 방법론이 달라져야 함을 알 수 있었다. 또한, 범용관측망 설계기법의 하나인 Integer Programming에 의한 방법과 지하수 정화 목적 관측망 설계기법의 하나인 Cost-to-go 함수 비교법을 동일한 대수층을 대상으로 적용한 결과, 각기 다른 관측정 위치를 얻었으나 요구되는 정보의 양은 비슷하였다. 두 방법 모두 지하수 오염을 모의할 정도의 정보만 확보되면 현장적용이 가능하며, 이를 통해 보다 객관적 근거에 이해 관측망 설계가 이루어질 것으로 판단된다.

• 한국수자원학회논문집
• /
• 제31권6호
• /
• pp.667-674
• /
• 1998

NAPL로 오염된 토양이나 지하수에 스팀을 주입하여 제거하는 과정을 모의하는 수치모형은 다양한 현장상황에서의 적절한 작업조건을 설계·평가하는데 매우 유용한 도구가 될 수 있다. 스팀주입에 의한 NAPL 제거과정을 다상, 다요소 시스템의 비등온 과정으로 기술하는 지배방정식에 기초한 T2VOC를 이용하여 1 및2차원상황에 대하여 수치해석을 수행하였다. 1차원의 경우 수치해는 실험상 어려움으로 인한 편차를 제외하고는 실험에서 얻은 컬럼내 온도분포와 비교적 좋은 일치를 보였다. LNAPL인 xylene과 DNAPL 인 TCE에 대한 2차원 해석도 상이한 물성에 상응하는 분포와 제거과정을 합리적으로 예측하는 것이 가능함을 보여주었다. 수치모형의 활용범위는 실험적으로 확인하기 여려운 기화에 의한 가스의 생성과 같은 복잡한 과정의 구명을 비롯하여 스팀주입기술의 현장적용시 매우 넓을 것으로 판단된다.

• 한국물환경학회지
• /
• 제24권1호
• /
• pp.63-68
• /
• 2008

This study was performed to assess the potential use of ozone or UV radiation for the treatment of water contaminated with sulfamethoxazole (SMX), which is frequently used antibiotic in human and veterinary medicines, especially focusing on the kinetic study and effect of pH. In a study using ozone alone, kinetic study was performed to determine second-order rate constant ($k_{O3,SMX}$) for the reactions of SMX with ozone, which was found to be $1.9{\times}10^6M^{-1}s^{-1}$ at pH 7. The removal efficiencies of SMX by ozone were decreased with increase of pH due to rapid decomposition of ozone under the condition of various pH (2.5, 5.3, 7, 8, 10). In a UV irradiation study at 254 nm, a kinetic model for direct photolysis of SMX was developed with determination of quantum yield ($0.08mol\;Einstein^{-1}$) and molar extinction coefficient ($15,872M^{-1}cm^{-1}$) values under the condition of quantum shielding due to the presence of reaction by-products formed during photolysis. For effect of pH on photolysis of SMX, SMX in the anionic state ($S^-$, pH > 5.6), most prevalent form at environmentally relevant pH values, degraded more slowly than in the neutral state (SH, 1.85 < pH < 5.6) by UV radiation at 254 nm.

• 한국물환경학회지
• /
• 제34권5호
• /
• pp.494-502
• /
• 2018

The purpose of this study was to understand distribution characteristics of organic matters through concentration of $BOD_5$, $COD_{Mn}$ and TOC in 31 streams in Han River region, and to establish the relationship among organic matter concentration, and discharge load and flow rate. Concentration of $BOD_5$ and TOC in 22 streams were above IV grade except 9, and the average 80.9 % of total organic matter (by TOC) accounted for dissolved organic type. Correlation among organic matter parameters were higher ($r^2$ > 0.78) and the relationship between TOC and $COD_{Mn}$ concentration was higher than $BOD_5$. Ratio of biodegradable organic matter/total organic matter in the 31 streams was estimated at 41.4 % with $BOD_5$ oxidation rate, and 78.0 % with $BOD_5/COD_{Mn}$ concentration ratio. Ratio of $NBOD/BOD_5$ concentration in four sites with $BOD_5/COD_{Mn}$ concentration ratio exceeding 1 ranged from 54.5 % ~ 79.3 %. Among 979 flow rate data measured at 31 streams, 87 % of measured data was below 0.1 cms and increased water pollution under low flow conditions. Correlation between $BOD_5$ concentration and $BOD_5$ discharge load in the watershed was low, and it was revealed that several streams have more $BOD_5$ delivery load than $BOD_5$ discharge load. Results suggest that many biodegradable forms of organic matter are being introduced into the stream from pollutant sources in the watershed.

• 상하수도학회지
• /
• 제27권3호
• /
• pp.299-312
• /
• 2013

This study investigated the contaminant loading and characteristics of particle size distributions(PSDs) in the rainfall runoff from two different sources, the pavement road and the ancillary parking lot, and then evaluated four different types of filter media(i.e., EPP, EPS, Zeolite, and Perlite) to treat runoff water. The results showed that runoff from the pavement road contains 5.6 and 20 times higher SS and Pb concentrations, respectively, than that from the parking lot. The particles smaller than $100{\mu}m$ occupied 89.8 % of runoff from the pavement road and 81.4 % of that from the parking lot by volume. The effect of the hydraulic loading, at 950 m/day filtering linar velocity and 40 cm head loss, was largest for Zeolite, followed by Perlite, EPS, and EPP. The return period of tested media calculated by the regression equation for head loss indicated that EPP has the longest life time. The average SS removal rate was similar for all media at between 84.9 % and 89 %, while the effect of various filter column heights was different, showing minimal for EPP and maximum for EPS. All filter media tested demonstrated over 95 % of SS treatment efficiency for the particles bigger than $100{\mu}m$, while for the ones smaller than $100{\mu}m$ the efficiency was in order of EPP(82.4%) > Perlite(76.1 %) > EPS(66.2 %) > Zeolite(65.2 %). The results in conclusion implies that EPP is most effective filter media for the highly contaminated fine particles from road runoff.