Performance assessment of major wastewater treatment plants (WWTPs) in the state of Georgia

A survey was conducted to report on the types and efficiencies of various treatment technologies being used at major wastewater treatment plants (WWTPs) in the state of Georgia. Twenty-four, full-scale wastewater treatment facilities with a design capacity of 37,850 m(3) d(-1) (10 Mg d(-1)) or greater were evaluated. One year of operating data for the 2003 calendar year was obtained from discharge monitoring reports (DMRs) provided by the Georgia Environmental Protection Division (EPD) in Atlanta. Additional information was gathered about facility operations and the types of chemicals used through review of EPD files and interviews with plant personnel. Data evaluated were: influent and effluent five-day Biochemical Oxygen Demand (BOD(5)), influent and effluent total suspended solids (TSS), effluent ammonia nitrogen (NH(3)-N), and effluent Total Phosphorus (TP). Effluent requirements for BOD(5) or five-day carbonaceous biochemical oxygen demand (CBOD(5)), TSS, ammonia nitrogen (NH(3)-N), TP, and dissolved oxygen (DO) vary by facility. Time series plots showing average effluent parameter concentrations versus month indicate the effectiveness of wastewater treatment as a function of type of treatment technology and temperature. Probability plots highlight the relationship between various effluent parameters and associated treatment technology. Fourteen facilities met all permit requirements, whereas ten of the facilities reported violations with regard to flow and/or effluent parameters. Chemicals utilized, design capacity, and monthly effluent concentrations are presented in this study.