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The objective of this study was to investigate the effect of pretreatment method and temperature on denitrification with some external carbon source. The experimental conditions were the temperatures of 7℃, 10℃, 15℃, 20℃, and the MLSS concentration of approximately 3000 mg/L. The experiments were conducted by denitrification test for pretreated distillery wastewater, food waste, and swine wastewater of extracted supernatant(P-1), hydrolysis(P-2), acid fermentation (P-3) and acid fermentation after extract(P-4), respectively. Based on the results of the experiments, the following conclusions are drawn. The nitrate removal rate coefficients(kDN) and the specific denitrification rates(SDNR) by classified pretreatment method of carbon source were 25.9~29.5, 25.6~26.0, 18.2~ 20.8 mg NO3--N/L·hr and 9.8~11.1, 9.1~9.8, 6.9~8.5 mg NO3--N/g MLVSS·hr. Also, the temperature coefficients(θ) of methanol, pretreated distillery wastewater, food waste and swine wastewater(P-4) at the temperature(7∼20℃) were 1.061, 1.050, 1.060, 1.067, respectively. Therefore, those values were much affected for carbon source more than pretreatment method. Whereas, the swine wastewater was shown the lowest on the denitrification rate.

This study was carried out to identify the major cause of sediments pollution in urban area. The six sediment samples were analyzed the organic and heavy metal with sediments of different particle size ranges. The prepared sediment samples were obtained after drying the separated with sieve as follows : >1,000 ㎛, 1,000~850 ㎛, 850~500 ㎛, 500~300 ㎛, 300~250 ㎛, 250~125 ㎛, 125~75 ㎛, 75~45 ㎛, and < 45 ㎛. The analyzed water quality constituents for graded sediments were chemical oxygen demand(COD), total nitrogen(TN), total phosphorus(TP), heavy metals (Fe, Cu, Cr, Fe, and Pb). The results indicate that most of particle size ranges of the contamination sediments was 250~125 ㎛, and portion of below 45 ㎛ was low. But most of the pollutants are associated with the finer fractions of the load sediments. As the results of analysis, the range and average values of COD, TN, TP, Fe, Cu, Cr, and Pb were 24,892~50,568 mg/kg, 353~543 mg/kg, 617~1,066 mg/kg, and Fe 1,410~2,725 mg/kg, Cr 21.50~51.99 mg/kg, Cu 12.96~84.48 mg/kg, and Pb 15.70~127.20 mg/kg, respectively. The results showed that the highest concentration site was commercial area. The relationship between sediment size and pollutants concentration have an inverse proportion. The removal of contamination sediments with frequently could be reduced the significant nonpoint pollutant load, because of the urban sediments contains considerable micro-particles and heavy metals.

As the exposure standards for o-dichlorobenzene is revised to the level of an advanced nation, it offers that the 25 ppm(150 mg/㎥) of TLV-TWA is newly established and the 50 ppm(301 mg/㎥) of TLV-STEL is changed to minimize the occurrence of occupational hazard of workers handling o-dichlorobenzene. The reason for the newly establishing has a setting background of the exposure standard of the advanced nation and a scientific approach through a research data and a review for human and animal toxicity, and has a technical approach through a review for the application of revised criteria for exposure as establishing to improve the working environment to catch hold of the actual conditions of working environment, and synthesizes the administrative and economic basis of impact analysis of regulatory for the ripple effect to the domestic industry as the application of revised criteria for exposure. Specially, most of the process to use o-dichlorobenzene in foreign and domestic set by considering to have a regular work cycle and to carry out an operation continuously. Also, the reason to change is that the property of an operation has injection for melting o-dichlorobenzene of intermediate products and has the situation as a lot of work and the work possible with high concentration exposure in short-term for sampling of the material response to confirm the status of reaction, and as the assessment according to current standards of maximum exposure can not actually measure the concentration of the moment, the concentration of the 15-minute exposure should be evaluated by looking, and the confirmation for whether it always maintained well below this concentration is set to consider technically difficult.

The odor from restaurants is considered as one of the environmental pollutions and is becoming a cause of serious environmental problems in downtown areas that have many residential districts and shops. In this study, the investigations on the emission characteristics and the odor causing substances was conducted. The control units and the odor producer were installed in laboratory. The analysis was conducted on ammonia, sulfur compounds, carbonyl compounds, amines, vocs which is emitted from beef, pork, chicken when cooked using gas range and charcoal fire. The range of the ammonia concentration from each meats was 2,011~6,503 ppb, acetaldehyde which is one of the carbonyl compounds was 27.2~267.2 ppb, trimethylamine was 0.6~3.9 ppb. The concentration of benzene was highest in vocs but meat originated benzene concentration was low in comparison with the concentration of benzene from the charcoal itself.

The ratio of water supply in Chungnam area is 64.4% and the ratio is great lower than 91.3% of national average of water supply. Therefore many population lived in Chungnam area have lived without public water supply system. In this paper, current status of small community water supply, water utility and water quality test result in Chungnam area were investigated. There are 951 small community water supply facilities and 1121 small community water supply facilities in Chungnam area. The survey showed 28.2% of small community water supply was older than 25 years and Among of small community water supply facilities, only 165 facilities have filtration treatment and the other 1893 facilities rely on only chlorination alone. Water quality test about 14 items were done and the result showed 361 facilities was inadequate among ot 11223 facilities. This means that 3.2% of the whole small community water supply did not satisfy present water standards. This paper aims to investigate current status of small community water supply in Chungnam and analyze trouble in the facility and maintenance for the consideration of water supply policy.

The industrial use of man-made mineral fibers(MMMF), has been increasing, particularly since the banning of most asbestos products. Glass fiber manufacturing is the high-temperature conversion of various raw materials into a homogeneous melt, followed by the fabrication of this melt into glass fibers. Emissions generated during the manufacture of wool fiberglass insulation include solid particles of glass and binder resin, droplets of binder, and components of the binder that have vaporized. To characterize VOCs and aldehyde compounds emissions from glass fiber process, we carried out this study. In order to give cohesion and mechanical properties to the glass wool mat, bindohesigents are added to the fibers, just after their production ofargeting in an ideal way to have one droplet of binder at each crossing of fibers. Generally, the binding materials consist of benzene-formaldehyde resin, urea resin, sicane and ammonium sulfate solution. Formohesind Curing section in the glass fiber manufacture process, small quantities of bindohesigents are vaporizedsind/or transform into VOCs & aldehyde compound. Some pollutants was very high concentration from mat-forming line and curing oven section, such as HCHO because vapor gas was generated as a resin polymerization.

The QUAL2E model has been widely used to predict water quality, but it doesn`t regard the changes(variations) of dissolved oxygen by a water plant or sticking algae and also BOD by floating algal death. Also, it doesn't regard the denitrification reaction and organic substances originated from dead algae, either. Thus it has a limitation to applicate for rivers which are influenced a lot by these changes. To solve these problems, QUALKO model is, therefore, developed in Korea. The purpose of this study is to make a comparative study on water quality prediction results by QUAL2E and QUALKO in Youngsan water system, and the results are as follows. When same coefficients in both QUAL2E and QUALKO are applied, The prediction results of BOD, T-P and T-N are good in both models. In QUAL2E model, the average values of R2 in calibration are 0.935, 0.765, 0.817 in BOD, T-N and T-P, respectively, and the cases of R2 in verification are 0.776, 0.856, 0.698, respectively. In QUALKO model, the average values of R2 in calibration are 0.945, 0.763, 0.821 in BOD, T-N and T-P, respectively, and the cases of R2 in verification are 0.787, 0.855, 0.685, respectively. These results show the possibility of QUALKO Model as a alternate when the number of calculation elements and a pollution sources etc exceeds the input limit of QUAL2E model. Because the QUALKO model is known as a good mnput limsystem in stagnated waters which has high algal growth, further research is necessary about the application of impounded watermsystems such as the downstream of Yeongsan river.

It is very important to save and reuse the water in order to cope with the global water scarcity. Therefore, the purpose of this study was developed the treating facility using changeable filter in order to reuse the used water or rainfall runoff as the flushing water for toilet and sprinkling water for road and vegetable plants. In order to study, the laboratory scale treating facility, which was composed with the processes of coagulation, flocculation, and filtration, was made, and preliminary test were performed to evaluate the possibility to use the treating facility. The results of treating test for artificial water made by soil were summarized as follows ; 1) Porous and compressible urethane filters with 100 ppi and 400 ppi were selected and successfully used as the changeable filter. 2) As the results of the preliminary test for the artificial colloid made by soil, flow weighted average removal efficiencies of SS were 35% to 40% under the condition of filtering flux of 1500 to 3000 m3/m2/d and pressure of 1 kg/cm2. And the range of mean particle size in effluent was 10~20 μm, and about 90% of filtered solids was washed out for 30 cycles of back washing movement. 3) For the test with turbidity, average removal rate was 31% for the case of filtering only, 32% for the case of coagulant injection and filtering, and 77% for the case of coagulation, flocculation and filtration. It was evaluated that the changeable filter facility with the preceding processes of coagulation and flocculation was possible to practical use to produce recycled water.

In this study, to control exhausting emission gas from meat cooking, it was surveyed at the restaurant to get the hang of characteristics. The experimental study was conducted to control exhausting emission gas from meat cooking restaurants. The target pollutants were oil vapor, oil mist, oil droplet and fine particles. The control units were composed of cooling effect and condensing unit, cyclone unit, electrostatic precipitator unit and grease filter unit. And, the control efficiency was conducted. It was showed that particle size distribution was 0.23~5 ㎛ and median diameter was 2~2.5 ㎛. In this paper, the recent updates including the emission characteristics and control efficiency will be reported.

For estimation of landfill gas generation, IPCC(Intergovernmental Panel on Climate Change) recommended using FOD model that is based on First Oder Decay equation and presented a default value for parameters. Especially a default value for DOCf(Fraction of Degradable Organic Carbon which decomposes) have problems that is not based on experimental data, and is not considered for loss with leachate. The objective of this study is to estimate DOCf about A landfill which have a waste composition data and the biodegradability data through BMP (Biochemical Methane Potential) test. Also DOCf loss in leachate calculated by Carbon Flow Analysis about A, B landfill. As a result, DOCf is a range of 0.58 to 0.62 from 1992 to 2000 and this values are higher than IPCC default value(0.5). From Carbon Flow Analysis, 40.11% of total disposed carbon is emitted by gaseous carbon(CH4) and 0.29% lost with leachate in A landfill. In case of B landfill, 36.92% of total disposed carbon is emitted by gaseous carbon and 0.30% of carbon lost with leachate. Therefore carbon loss through leachate is less than 1% and this may be neglected for estimation of DOCf.

Recently the importance of the phosphorus management is being augmented according to the designation (2005.12.30 Ministry of Environment) object material in regulation of total emission from the Ministry of Environment. Generally treatment efficiency of biological process is in the process of using is high and treated water quality is stable. However, the process requires wide site area and has difficulties in the advanced treatment for recycling. Electrocoagulation (EC) process is the electrochemical production of destabilization agents that bring about charge neutralization for pollutant removal. EC process is compact, so it needs small scale site area and treatment efficiency is high. Also, this process is characterized by reduced sludge production, uselessness of chemicals, and easy operation. This research escape optimum plan factor for removal of phosphorus in lake by using hybrid system(Electrocoagulation reactor, Settling tank, Filtration tank). As the result electric current : 3ampere, the pH : Neutrality and filtration tank existing the condition was shown the highest removal efficiency. Concentration of PO4-P, T-P and CODcr was measured 0.016 mg/L, 0.022 mg/L and 1.5 mg/L from under condition of optimum, the removal ratio was shown 94.1%, 95.3% and 77.5%. Also expense of the electric coagulation is reduced than expense of chemical coagulation about 0.56 time. so it will be able to forecast the application possibility of electric coagulation.

South Korea's steel industry, a representative industry that uses a large amount of water, has produced various wastewater and is posing various problems for the treatment. In this study, a rolling oil wastewater of“P”steel manufacturer was treated through the ultra-filtration membrane. Results showed that the wastewater was purified over 95 percent despite possible changes in pH or pressure. If the ultra-filtration membrane is used, test results showed, the wastewater could be concentrated about 35 times thicker. Operating time for concentration can be reduced with high pressure. But the optimal pressure is estimated at 1.47 bar since the embrane is more contaminated in accordance with the increase of pressure. Operating time for concentration could also be reduced by increasing the pH. Increase in pH is good for the increase of concentration rate or flux of the wastewater. But it should also be taken into consideration that additional chemicals are needed to increase the pH. Wastewater treatment using the ultra-filtration membrane is more efficient than previous air floatation or evaporation methods and less cost in terms of installation and management of facilities. And, therefore, there should be further studies on the ultra-filtration membrane method which has lots of strong points for the wastewater treatment.