Environmental Contamination by Accidental Chemical Discharge and the Countermeasures against them in Water Supply Systems

Abstract

Environmental contamination by chemical spill or discharge in water is high concern especially in resources of water suppliers. As for chemical contamination accidents in drinking water source, we hereby demonstrate some case studies. In 2012, hexamethylenetetramine contamination was detected by formaldehyde produced in chlorination in drinking water treatment process, which caused a great water suspension in the metropolitan area. Chemical contamination was also found in rivers in Niigata which caused mal odor in drinking water in 2016. The compound was finally identified using accurate mass spectrometry. In these cases, combination of chemical analysis and information collection including treatability is a key to solve chemical contamination. Comprehensively administrative countermeasures in drinking water supply systems are described, i.e. water safety plans and 'continuous water supply with restriction for drinking.'