ASSESSMENT OF GROUNDWATER CONTAMINATION RISK FROM NONCHEMICAL STRESSORS IN WASTEWATER

摘要

Chemical risk analysis approaches have been applied extensively to examine the effect of chemical stressors in wastewater on the risk of ground-water contamination. We have developed multidisciplinary water management models that examine the risk to groundwater caused by chemical stressors such as nitrogen and chlorides. These models examine the impact under a variety of scenarios, taking into account hydrological, technological, economic, and regional planning aspects. Nonchemical stressors are a major concern in wastewater, but methods of risk assessment for these stressors are less developed. Pharmaceuticals are a well known source of contamination of urban wastewater, and their negative impact on the environment and on human health has been well documented. Microbial agents are considered a major biological stres-sor and their existence in wastewater has caused epidemic outbreaks in several cases. This paper analyzes the application of our water management models to evaluate the effect of nonchemical stressors in wastewater on the risk of groundwater contamination. We examine different scenarios of concentrations of Pharmaceuticals and microbial agents in wastewater, and show how chemical risk assessment methods can be applied to decision making for optimal wastewater treatment, based on economic considerations as well as environmental security and human health considerations.