Adsorption by granule activated carbon(GAC) is recognized as an efficient method for the removal of perfluorinated compounds(PFCs) in water, while the poor regeneration and exchange cycles of granule active carbon make it difficult to sustain adsorption capacity for PFCs. In this study, the behavior of PFCs in the effluent of wastewater treatment plant (S), the raw water and the effluents of drinking water treatment plants (M1 and M2) located in Nakdong river waegwan watershed was monitored. Optimal regeneration and exchange cycles was also investigated in drinking water treatment plants and lab-scale adsorption tower for stable PFCs removal. The mean effluent concentration of PFCs was 0.044 0.04 PFHxS g/L, 0.000 0.00 PFOS g/L, 0.037 0.011 PFOA g/L, for S wastewater treatment plant, 0.023 0.073 PFHxS g/L, 0.000 0.00 PFOS g/L, 0.013 0.008 PFOA g/L for M1 drinking water treatment plant and 0.023 0.073 PFHxS g/L, 0.000 0.01 PFOS g/L, 0.011 0.009 PFOA g/L for M2 drinking water treatment plant. The adsorption breakthrough behaviors of PFCs in GAC of drinking water treatment plant and lab-scale adsorption tower indicated that reactivating carbon 3 times per year suggested to achieve and maintain good removal of PFASs. Considering the results of mass balance, the adsorption amount of PFCs was improved by using GAC with high-specific surface area (2,500m2/g), so that the regeneration cycle might be increased from 4 months to 10 months even if powdered activated carbon(PAC) could be alternatives. This study provides useful insights into the removal of PFCs in drinking water treatment plant.

The study was carried out to evaluate the new analytical method of phthalate esters(diethylphthalate, di-n -butylphthalate, butylbenzylphthalate, bis(2-ethylhexyl)phthalate), one of the endocrine disruptors, which were performed by GC/MS-SIM(selected ion monitoring). The phthalate esters were extracted from water samples using solid-phase extraction on C18 columns. It investigated that the extraction recovery rate of phthalate esters with different solvents and solvent volume. The optimal solvent was dichloromethane and proper volume of dichloromethane for recovery of phthalate esters was 4 mL. There were good linearities(above R2=0.9975) in the range 0.01～0.50㎎/L, and the detection limits were below 0.01～0.03㎍/L. The recovery rates, RSD and MDLs for phthalate esters were 80～114%, 5.0～8.1% and 0.03～0.11㎍/L, respectively. This method shows a good precision of phthalate esters.

We investigated and analysed the actual conditions and characteristics of railroad noise levels for 17 sites in the vicinity of the Seoul-Pusan Line. The results are summarized. as follows : 1) Railroad noise level ranged to 64∼74 L_eq dB(A) at day time and ranged to 60∼72 L_eq dB(A) at night time. 2) Increased night noise level depend on the increase of trains passing at night time. 3) The major factor of increased noise level in the vicinity of stations are using loudspeakers and stream whistle on trains. 4) Decreased effect of noise according to distance is able to be described quantitatively using regression equations of multiplicative model. L_eq=78.59 X^-0.056 n=25, r=-0.994, s.e.=1.007 P_av =105.68X^-0073, n =25, r =-0.997, s.e. = 1.007 Also increased and decreased effect of noise according to floor in apartment is able to be described quantitatively using regression equations of multiplicative model. L_eq = 64.238 X^0.0567, n = 39, r = 0.787, s. e. = 1.004 P_av. = 79.963 X^0.0254 n = 39, r = 0.689, s. e. = 1.056 5) Average noise level in high floor is over 70L_eq dB(A) at day and night time, so more detailed soundproofing countermeasured in high floors apartment is required.