Recycling ofWater Treatment Plant Sludge via Land Application: Assessment of Risk

Water treatment sludges (WTS) offer potential benefits when applied to soil and recycling of the waste stream via land application has been proposed as a management option. Recycling of WTS to the land helps conserve landfill disposal capacity and natural resources, but potential environmental and human health risks must be properly evaluated. In this study, alum, ferric and lime WTS samples were collected from 34 water treatment facilities in Florida, US. The concentrations of several inorganic and organic pollutants were analyzed. The results were compared to risk-based soil contaminant thresholds to assess possible human health risk. Leached concentrations were compared to water quality thresholds to examine the potential for