Feasibility Study of As-Received and Modified (Dried/Baked) Water Treatment Plant Residuals for Use in Storm-Water Control Measures

Abstract

Use of water treatment plant residuals (WTRs) in storm-water control measures (SCMs) is a sustainable alternative to landfill disposal of WTRs. However, research is needed to determine how effective WTR-amended SCMs would be in field-scale applications and what modifications can be implemented to improve performance. The modifications examined in this study were oven-drying (105°C) and baking (1,000°C) of the WTRs. Results showed that both modifications increase the hydraulic conductivity by two orders of magnitude. Dried WTRs showed no loss of phosphate removal potential compared to the as-received WTRs. Baking the WTRs lowered the phosphate removal potential but prevented manganese resuspension. The as-received WTRs, as well as both modifications, removed copper, lead, and zinc from storm-water runoff to below detection. Taken together, these results suggest that amending SCMs with modified WTRs has the potential to enhance the water quality improvement processes of SCMs while maintaining the infiltration capacity required for water quantity control.