Impact of Contaminant Specific Corrective Action Strategies on Wastewater Treatment Plant Performance and Recovery

Toxins entering a wastewater treatment plant (WWTP), whether present due to an accidental spill or intentional release, are a nuisance to that plant's ability to treat wastewater and a threat to public safety. A corrective action plan matrix (CAPM) is a tool that can be used by operators to eliminate or mitigate the impact of a toxic upset. This study seeks to further develop a working CAPM that could be easily implemented in the field by testing proactive operational changes specific to the nature of the toxin entering the WWTP, namely calcium hypochlorite and cadmium. Three laboratory-scale, continuous flow wastewater treatment trains were operated in parallel to simulate the toxic upsets and elucidate the remedial effects of two corrective action strategies. While corrective actions were deemed unnecessary for a toxic shock involving calcium hypochlorite, the strategy addressing the cadmium spill showed promise in minimizing peak biomass inhibition.