Our team was tasked by Eljen to find an alternative secondary filtering material to replace the ASTM C-33 sand used in their Geotextile Sand Filter (GSF). The GSF is a septic leach field and the secondary filtering material provides extra treatment to the effluent that is passed through the system, namely reducing the amount of total suspended solids (TSS) and biochemical oxygen demand (BOD) in the effluent. The replacement secondary filtering material must replicate the ASTM C-33 sand's properties of filtering, non-clogging, and facilitating the growth of a biomaterial layer.

Our team collaborated with Environmental Engineering 4 on this project.