Envirogen Technologies, Inc. has started up an odour control system for the City of Fort Smith, Arkansas that will remove hydrogen sulfide (H2S) and other odour-causing compounds from air at the city’s P-Street wastewater facility. The new system consists of a single chamber biofilter and will remove more than 99% of average inlet concentrations of H2S and 90% of other organic reduced sulfur compounds. The system is designed to handle up to 12,000 cubic feet per minute (cfm) of air from the facility’s influent pub station, pretreatment system, bioselector and inlet channels. The Fort Smith installation is another example of Envirogen’s ‘green’ biological treatment technology for odour control that is becoming the option of choice across the United States from small to very large requirements. It will be Envirogen’s first biofilter installation in the State of Arkansas.