Research On The Early-warning System And Models For Abrupt Accidents In Water Source Areas Of Rivers

In recent years, the abrupt water quality pollution accidents have broken out frequently in the river basins, especially in the drinking water source areas of rivers due to many kinds of factors such as enterprise's environmental illegality,safety accidents in production,layout risk of industry,maritime and road accidents and big flood influence in our country, these accidents have become one of the most serious environmental problems that our country faces. Environmental Risk Assessment is a new domain in the protection of environment for the time being, its appearance indicates an important strategic turning from the former treatment after the pollution to the prediction and the carrying out of effective management before the pollution.Focusing on the environmental risk assessment and emergency management system of the abrupt water quality pollution accidents in the drinking water source areas of rivers, this paper lays stress on the mathematical simulation problems of the temporal and spatial change of the concentration of the poisonous and harmful pollutants discharged from the the abrupt water quality pollution accidents, the staging prewarning and prediction model and emergency management system for the the abrupt water quality pollution accidents in the drinking water source areas of rivers are constructed, in the hope of predicting the aftermaths of the accidents promptly, seeking the optimal treatment measures in the end of the accidents, so as to insure the safety of the water quality in the drinking water source areas of rivers. The main research contents and conclusions can be summarized as the following:(1) In terms of the environmental risk assessment, two classes of risk sources of the abrupt water quality pollution accidents in the drinking water source areas of rivers are identified comprehensively. By applying the Fault Tree Analysis(FTA) method, the source terms for the abrupt water quality pollution accidents in the drinking water source areas of rivers are analyzed.(2) According to the characteristics of the abrupt water quality pollution accidents, the staging prewarning and prediction models for the abrupt water quality pollution accidents in the drinking water source areas of rivers are established.(3) From the following four aspects of emergency organization system, emergency response mechanism, emergency treatment mechanism, emergency guarantee system, this paper sets up an emergency management system for the abrupt water quality pollution accidents in the drinking water source areas of rivers systematically.(4) This paper takes the Taizhou river section of Yangtze River (the Xinfu Floodgate - North Sand) as the background for studying, taking the drinking water source areas in the Taizhou river section of Yangtze River as the application embodiment, studying in the tide sect of the Yangtse River, under the most disadvantageous hydrological condition, during neap-spring tidal cycle and flood-ebb fluctuations, the distribution of concentration contours of the accidentally discharged pollutant mixed belts from the point source pollution of a factory, and its prewarning and prediction, risk assessment and emergency management.The result of the study shows: under the most disadvantageous hydrological condition, the most risk pollutant discharged from the Taizhou A Chemical new factory accidentally is COD_Mn, its density is lower than the second class standard value of The Surface Water Envrionmental Quality Standard(GB 3838-2002), the risk value to the water quality of the upstream and downstream water intake is acceptable.