Ali Akbar Alimoradi and Ahmad Sayyahi
The present study aims to investigate the procedures to collect and dispose of (treat) municipal wastewater with special emphasis on regional, economic and environmental considerations in Semnan province. The study purports to propose a procedure to collect and treat sewage in Semnan, which bears no adverse environmental effects and matches the regional and economic conditions. The current disposal method is the traditional underground sewage soakage well, 5-10 meters deep, two of which are typically dug in every house. This method seems functional as the soil has good permeability qualities. However, as the sewage disposed of this way sinks down and joins underground aquifers, it contaminates the aquifers. The results showed that the use of stabilization pond is the most viable method to treat wastewater in Semnan considering the operational ease of wastewater treatment plants, insensitivity to qualitative and quantitative changes in wastewater quality, availability of the equipment in Iran, lack of a need for expensive waste sludge treatment equipment, lack of a need for highly-skilled operators for operation and maintenance, cheap lands and good climatic conditions.
