2017, Vol.26, No.2

Journal of Environmental Impact Assessment 2023 KCI Impact Factor : 0.51

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

CCS (Carbon Capture and Storage) is a technical process to capture CO2 from industrial and energy-based sources, to transfer and sequestrate impressed CO2 in geological formations, oceans, or mineral carbonates. However, potential CO2 leakage exists and causes environmental problems. Thus, this study was conducted to analyze the spatial and temporal variations of CO2 fluxes and concentrations after artificial CO2 release. The Environmental Impact Evaluation Test Facility (EIT) was built in Eumseong, Korea in 2015. Approximately 34kg CO2 /day/zone were injected at Zones 2, 3, and 4 among the total of 5 zones from October 26 to 30, 2015. CO2 fluxes were measured every 30 minutes at the surface at 0m, 1.5m, 2.5m, and 10m from the CO2 releasing well using LI-8100A until November 13, 2015, and CO2 concentrations were measured once a day at 15cm, 30cm, and 60cm depths at every 0m, 1.5m, 2.5m, 5m, and 10m from the well using GA5000 until November 28, 2015. CO2 flux at 0m from the well started increasing on the fifth day after CO2 release started, and continued to increase until November 13 even though the artificial CO2 release stopped. CO2 fluxes measured at 2.5m, 5.0m, and 10m from the well were not significantly different with each other. On the other hand, soil CO2 concentration was shown as 38.4% at 60cm depth at 0m from the well in Zone 3 on the next day after CO2 release started. Soil CO2 was horizontally spreaded over time, and detected up to 5m away from the well in all zones until CO2 release stopped. Also, soil CO2 concentrations at 30cm and 60cm depths at 0m from the well were measured similarly as 50.6±25.4% and 55.3±25.6%, respectively, followed by 30cm depth (31.3±17.2%) which was significantly lower than those measured at the other depths on the final day of CO2 release period. Soil CO2 concentrations at all depths in all zones were gradually decreased for about 1 month after CO2 release stopped, but still higher than those of the first day after CO2 release stared. In conclusion, the closer the distance from the well and the deeper the depth, the higher CO2 fluxes and concentrations occurred. Also, long-term monitoring should be required because the leaked CO2 gas can remains in the soil for a long time even if the leakage stopped.

Recently mountain tourism has been promoted and introduction of railroads with utilizing mountain resources is being planned. With the government policies to increase the share of eco-friendly transportation on railroad, national double-tracking of single rail and improvement projects are on going. However, the eco-friendly railroad policy suggests the environmental impact assessment items only on air quality, water quality, geographical/geological features, fauna/flora, natural/environmental resources, noise/ vibration, and recreation/landscape. And for fauna/flora and natural/environmental resources, confirming the presence of environmental protection zone is enough to satisfy legal requirement. This study suggested to evaluate environmental/ecological values with quantitative data. Evaluation indices and evaluation items have been selected to provide the data. Each of the subject map and railroad network was overlapped. The study selected naturalness and diversity as major indicators and calculated weight values of the items under the indicators, which are to be usd for the selection of the sites for railway development. This assessment method could be applied to the environmentally friendly construction of railroads in the future.

Many studies on climate change and its impacts use a single climate scenario. However, one climate scenario may not accurately predict the potential impacts of climate change. We estimated temperature and precipitation changes by 2070 using 17 of the CMIP5 Global Climate Models (GCMs) and two emission scenarios for three spatial domains: the Asian continent, six East Asia countries, and South Korea. For South Korea, the range of increased minimum temperature was lower than for the ranges of the larger regions, but the range of projected future precipitation was higher. The range of increased minimum temperatures was between 1.3 ˚C and 5.2 ˚C, and the change in precipitation ranged from - 42.4 mm (- 3.2%) and + 389.8 mm (+ 29.6%) for South Korea. The range of increased minimum temperatures was between 2.3 ˚C and 8.5 ˚C for East Asia countries and was between 2.1 ˚C and 7.4 ˚C for the Asian continent, and the change in precipitation ranged from 28.8 mm (+ 6.3%) and 156.8 mm (+ 34.3%) for East Asia countries and from 32.4 mm (+ 5.5%) and 126.2 mm (+ 21.3%) for the Asian continent. We suggest climate change studies in South Korea should not use a single GCM or only an ensemble climate model’s output and we recommend to use GFDL-CM3 and INMCM4 GCMs to bracket projected change for use in other national climate change studies to represent the range of projected future climate conditions.