Innovative use of Orenco AX100 to treat primary effluent on residential projects Working with DSH Associates to design and install wastewater treatment systems for residential projects has been a great experience. The whole system is a cost effective way to manage and treat septic effluence for mid sized residential developments where connection to municipal sewer systems isn't possible. Working closely with DSH Associates, Infradraft has designed the complete system for developments with over 100 large houses in mountaineous areas of Tennessee