Research On Environmental Risk Source Identification Of Sudden Water Pollution Accident Based On Safety Theory

In recent years, the frequency of water pollution incidents increased year by year, leading to a significant impact on the aquatic environment and socio-economic. Most of these sudden water pollution accidents evolved from the safety incidents, its source is mainly in petroleum chemical industry dependent on water resources for production or use of hazardous substances. Seven of the most important river basin accounted for 81.1% of the total water supply, they played a huge role in the national economy. Therefore, this paper carried out the research on sudden water pollution accident source identification of environmental risk combined with theory and method of safety assessment, and established a environmental risk source identification system for sudden water pollution accident. As a resulte, it can support the decision-making for risk management of water environment, to ensure the safety of the water resources.First of all, In this study, there was detailed data information of 8 risk sources obtained, based on the investigation of the Songhua River water pollution accident sources. In the analysis of the environmental risk sources of sudden water pollution accident, there are three key factors, including the characteristics of risk source, safety factors, and the status of water environment risk receptor, that affect the risk level of environmental risk sources of the sudden water pollution accident, combined with the related theories of environmental risks and safety risks. Then, the key factors for risk identification have been found.Second, reference to the classification method for environment pollution accidents in "National Environmental Emergency Plan", the environmental risk sources of sudden water pollution accident were also divided into four grades: the general environmental risk source of sudden water pollution incident (gradeⅣ), greater environmental risk source of Sudden water Pollution Accident (gradeⅢ), significant environmental risk source of sudden water pollution incident (gradeⅡ), particularly significant environmental risk source of unexpected water pollution incident (gradeⅠ). So, the classification system of water risk source identification was established.Third, using the combined method of AHP and fuzzy comprehensive evaluation, this study built the environmental risk source identification technology system of water pollution accident. For one thing, reference to environmental assessment model PSR, the environmental risk source identification index system of sudden water pollution accident, composed of 4 layers: the target layer, rule layer, theme and index layer, and 3 criterions, corresponding to the three themes and 11 specific indicators, was established, based on the method of dangerous degree assessment and flammable, explosive, toxic material hazard source evaluation in safety assessment. Then, the evaluation criteria set and the weight set of the indicators for environmental risk source identification of sudden water pollution accident were also established. using trapezoidal fuzzy relationship matrix distribution function, selecting the matrix multiplication as a fuzzy operator, all of these constructed a complete set of technology system of environmental risk source identification for sudden water pollution incident.Finally, it was the application of the technology system of environmental risk source identification for sudden water pollution incident. this study identified 8 risk sources in the Songhua River basin, 3 general environmental risk sources of sudden water pollution accident, 4 greater environmental risk sources of sudden environmental pollution accident, and 1 significant environmental risk source of sudden water pollution incident included. It provided a scientific basis for Water environment management of the Songhua River basin.