The Van Buren South Wastewater Treatment Plant (South Plant) was first constructed as a primary treatment facility in Van Buren, Arkansas in the 1960s. It was expanded to a secondary treatment facility with the construction of aerated lagoons in 1973. In response to more stringent NPDES limits and a Consent Administrative Order from the Arkansas Department of Environmental Quality, the Van Buren Municipal Utilities selected Hawkins-Weir to design treatment upgrades and improvements to the South Plant in 2004. The project included conversion of the mechanically aerated lagoons to a complete-mix lagoon with diffused aeration to provide ammonia nitrogen removal and increase the plant’s treatment capacity from 3.1 MGD to 4.0 MGD. In order to address total residual chlorine limits for effluent in the permit, the disinfection method was changed from a gas chlorine system to a new ultraviolet (UV) system. The Project design also included new influent screening, two secondary clarifiers, sludge recirculation, flow monitoring, and emergency standby power. In addition to providing design services, Hawkins-Weir also provided construction management and administration services during construction.