Real-time control (RTC) strategies in stormwater biofilters can enhance the removal of trace-level organic chemicals (TrOCs), yet performance depends on compound properties and rainfall conditions. This study investigated system dynamics, soil moisture, and redox potential (oxidation-reduction potential, ORP) in RTC and conventional biofilters (Non-RTC) under different antecedent dry weather periods (ADWP) to clarify mechanisms influencing TrOC removal. Mesocosm-scale vegetated columns operated for 1 year were sampled over 8 months under Non-RTC and three RTC configurations, with embedded sensors continuously monitoring moisture and the ORP in the unsubmerged and submerged zones. RTC-induced system operations significantly altered moisture and ORP conditions within the biofilters (p-value Non-RTC systems, significantly improving removal of TrOCs favoring aerobic biodegradation (p-value Non-RTC increased sulfamethoxazole and atrazine removal by up to 20.1%. Microbial profiling revealed modest increases in the diversity and abundance of TrOC-degrading genera under RTC (up to 4-fold). These findings demonstrate RTC's potential to optimize TrOC removal via active control of system dynamics, supporting broader and more sustainable operation of stormwater biofilters.
Zhang et al. (Wed,) studied this question.