화학사고 시 강우와 누출물질의 물성에 따른 하천과 저토의 오염도 예측을 위한 다매체 동태모형 개발 ; Development of a multimedia model to predict the effects of rain and properties of chemicals accidentally released on the contamination characteristics in the river water and the bottom sediment

Among chemical accidents that occur in Korea, leak-related accidents account for about 77% of all accidents, i.e., it is important to prepare measures to prevent and respond to leakage accidents. However, the models used to predict and evaluate chemical accidents are mainly limited to the atmosphere, and the models for evaluating water pollution do not sufficiently consider the deposition of pollutants from the atmosphere. However, since chemical accidents pollute all environmental media by interaction between media, a model that reflects the dynamic characteristics of the chemical leaked by accident in each medium is necessary. In addition, in the case of rainfall, chemical substances are removed from the atmosphere to the surface by wet deposition, and chemical substances deposited to soil can contaminate water through runoff. However, the general models currently used are not able to evaluate the effect of rainfall sufficiently. Therefore, this study implemented an extended multimedia dynamic model for chemical accidents (CAM) that can quantitatively evaluate the contamination level for air, soil, water, and sediment. The reliability of model and the effects of chemical accidents on the water and sediment were analyzed through rainfall and wind scenarios, with the properties of the leaked chemicals. As a result of reliability evaluation of CAM, the spatiotemporal prediction tendency of CAM with WASP8 was similar, and the Cwater was in adequate range compared to that of WASP8. However, in the case of Csediment, CAM predicted higher than WASP8. This was because the lower the Koc of pollutants, the more adsorption-desorption between the water and the sediment, which WASP8 does not consider, acted as one of the main transport mechanism for the pollutants from the water to the sediment. However, since this mechanism is one of the main mechanism of chemical transportation between the media, it can be accepted as the advantage that CAM simulates the transport of pollutants more precisely than WASP8. The effect of ...