By reference to the wastewater treatment plant of Taranto (Apulia Region. S Italy), a typical Mediterranean city. an odour impact assessment has been carried out in order to evaluate the annoyance for the population living in the neighbourhood In adverse weather conditions ("worst scenario"), the study indicated a limited off-site odour impact at the 300 in setback distance dictated by local regulation. (C) 2009 Elsevier B.V. All rights reserved.