2007, Vol.16, No.6

Journal of Environmental Impact Assessment 2023 KCI Impact Factor : 0.51

pISSN : 1225-7184
https://journal.kci.go.kr/kseia

The air quality modeling was carried out to assess the impact of air quality for large scaleurban development. The site for the assessment is Multi-fuctional Administrative City whichlocates in Yeongi-gun, Chungcheongnam-do and estimated population in 2030 is 500,000.Two automatic weather monitoring stations were installed to monitor the meteorologicalvariables for a year and upper air meteorological parameters were measured using radiosondefor 5 days with 4 hours interval in every season. The air quality of standard air pollutants werealso measured for 5 days continuously in every season.The results of wind field analysis based on the site measurements and CALMET modelingshowed that the valley and mountain winds were prevailed when the sypnotic wind was weak.It also showed that wind speed and directions were highly space-variable within the site basin.The variable wind characteristics implies that the Gaussian dispersion model such ISC3 andAERMOD are not appropriate and the unsteady-sate Lagrangian model such as CALPUFF ispreferable.CALPUFF model was applied to assess air quality impact of new sources. The new sourceswere those for individual and group heating facilities as well as the traffic increases. The resultsshowed that the estimated concentrations of CO and SO2 pollutants by summing the impactconcentration of new sources by the dispersion model and the ambient air concentrations by thesite measurements were acceptable but those of PM-10 and NO2 would violate ambient air quality standards at several locations due to high ambient air concentrations. It is recommended that the emission reductions near the site should be enforced to improve the ambient air quality.

To examine the sedimentary geochemical characteristics of sediment in the Tamjin River andDoam bay, the analysis was conducted, using the sample obtained in February 2000, on thegrain size and the contents of metallic elements and organic carbon. The factors that influencethe geochemical behavior of metallic elements in the surface sediment are grain size, organism,surrounding soil and CaCO3. To find out the pollution level of metallic elements, theenrichment factor (EF) and the index of geoaccumulation (Igeo) were researched. The majority ofmetallic elements sustain their values in natural state. The elements such as K, Ba, Zr, etc.appear to be rich in some places. The EFand Igeo of P, Cu, Zn, and Pb, which belong to toxicheavy metals, are partly related with man-made pollution. P and Cu have a high EF, Pb has ahigh I geo and Zn is high in both EFand I geo. The low contents of P and Cu are not likely to berelated with the pollution of water environment. However, given the development of relativepollution, the research and the management regarding the pollutants are needed. Because Pb,naturally enriched by geological characteristics, has a large influence on water environmentalong with Zn, the adequate measures against man-made pollution should be worked out.

This study investigated the predicted and abserved outflow of groundwater which occurredduring tunnel constructions. Among the 586 road construction projects from 1986 to 2006, 4route 25 tunnel construction areas and 26 waste water treatment facilities under constructionwere studied.Most of the tunnel outflow prediction in EIA (Environmental Impact Assessment) processhave been classified into the 17 types of units depending on the assessor’s options, which havenot conformed to the request of the residents and non government organizations.The investigation results showed that the outflow of underground water in tunnelconstruction areas averaged about 0.133m3/km · min with the maximum 0.386m3/km · min,and that the outflow mostly occurred in the early stage of tunnel excavation and diminishedgradually. The prediction of outflow of underground water in the EIA process showedexcessive results compared to observed outflow, the even 51.7 times.Consequently for more realistic prediction, current EIA method for prediction of outflow ofunderground water in tunnel construction areas has to adopt numerical methods coupled withhydraulics and geologic informations from unit methods of present time.