In 2007, 45,163 domestic industrial direct/indirect discharge sources were registered in Korea, which have been categorized into 82 divisions based on the characteristics of their products, raw materials and wastewaters. The purpose of this study was to set priorities using a risk assessment of pollutants toxic weighting for each industrial category with respect to pollution prevention and control. This study developed the upgraded Modified Toxic Weighting Factors (MTWFs) rather than the Toxic Weighting Factors (TWFs) suggested by the United States Environmental Protection Agency (USEPA) with respect to domestic environmental regulations, and the assessment of existing databases of domestic industrial wastewater characteristics for the 82 categorized industries in Korea. Finally, priority of industrial categories and pollutants were established to determine the target industries and pollutants requiring controls. High contributing categories in order of their pollution loads were pulp, paper and paper products manufacturing, dyeing and processing facilities, etc. The top 10 industrial category loads accounted for 76.0% of the total effluent equivalent kilograms of pollution. High contributing categories, in order of their toxic level were synthetic resins and other plastics manufacturing, leather and fur processing and manufacturing.
Keywords: industrial wastewater, Modified Toxic Weighting Factors (MTWFs), risk assessment, water pollution