Dispersion modeling and air quality measurements to evaluate the odor impact of a wastewater treatment plant in İzmir

Abstract

Municipal wastewater treatment plants (WTP) are potential sources of offensive odors that can create annoyance in the communities. Therefore, odors have been rated as the primary concern of the public relative to the implementation of wastewater treatment facilities. In this study, dispersion modeling and air quality measurements were used to quantify the potential odor impact around a Wastewater Treatment Plant in İzmir. AERMOD atmospheric dispersion model was used to predict odor levels in OU/m3 around the treatment plant. Odor measurement results of the wastewater treatment plant units that are considered as area odor sources were used for odor modeling. Air quality measurements of H2S and NH3, which are two main odorous compounds emitted from wastewater treatment plants, were also conducted by using passive sampling methodology in the surroundings of the plant to evaluate the odor impact of the plant. Both odor emission and air quality measurements were conducted in the period of July–august 2018 for evaluation of odor impact, and consequent application of dispersion model. The air quality measurements of the pollutants which exceed the odor threshold values do not create annoying odor impact on residential areas. The dispersion modeling demonstrates that the odor concentrations exceeding 10 OU/m3 concentration levels that can be measured olfactometrically also do not create an odor impact on local residents.