Study On Methods Of Risk Assessment In Exemption Management For Hazardous Wastes

The hazardous wastes in our country are large amount, while the treatment and disposal resources of which are limited, this leading to portion of hazardous wastes generators be omitted in management, and the contradiction between which is difficult to solve in the short term. According to the current status, relevant management requirement of the hazardous wastes is resorted to:reducing the management level of some hazardous waste generators and absorbing them to a more perfect management system to control pollution and reduce risk. The experiences in developed countries show that the exemption technology of hazardous wastes meets the requirement of the hazardous wastes management in our country aptly.The practicality of the method given by the paper was proved through a case study for the electroplating sludge in the experimental city of our country. The results showed that the permitted exemption amount of the electroplating sludge to the target municipal solid waste landfill was 3.4 t per year. Some small quantity generators of the electroplating sludge could be exempted, the electroplating sludge generating by which could be disposed as municipal solid and the total exemption amount should not exceed 3.4t per year.Through comparing of risk assessment methods, environmental risk assessment was chosen as the evaluating way of hazardous wastes exemption management, and the electroplating sludge was taken as an example to study the exemption management evaluating way of hazardous waste generators in our country. The main contents were as follows:the target pollutants in the electroplating sludge were identified as Cr,Cu,Ni,Zn,Cd,Mn,Ba,Pb,CN- and F; the typical exposure scenes of the disposing were established; EPACMTP model were selected as the technological core of the exemption management evaluation method basing on the exposure scenes; through the analysis of risk assessment parameters in the exemption management evaluation method, the amount of hazardous wastes generating per generator per unit time was chosen as the grading index for exemption, the feasibility of which was analyed by the sensitivity analysis.In this paper, the criterions, regulations and technical documents relevant to the hazardous wastes exemption management both in home and abroad were investigated. The results showed that the exemption management system of hazardous wastes in American was more perfect, which provided a good idea to the management of hazardous wastes in our country:studying the evaluating methods of exemption management of hazardous waste generators was helpful to establish exemption management system of hazardous wastes for our country.