Eljen Geotextile Sand Filter (GSF)
Geotextile fabric and plastic core materials function together to provide vertical surface area for biomat management and oxygen transfer in each GSF Module. In the GSF System, treated effluent is applied to the receiving soil, which increases soil acceptance. Additional filtration and dispersal is provided by the Specified Sand layer under and around the GSF units. This sand layer remains in an unsaturated state allowing for the free flow of effluent and beneficial bacteria.
Eljen Geotextile Sand Filter Key Features:
Integrated treatment and dispersal
Site installation flexibility
Reduced impact on the site
Easy to handle, lightweight
How the GSF System Works
In lieu of onsite septic leach field systems, Eljen offers its GSF (Geotextile Sand Filter). Testing performed by independent, third parties verifies the performance of the GSF under different conditions, but the system is composed of a primary treatment zone (containing the GSF Module) and a secondary treatment zone (Specified Sand layer). Over the GSF Module is a perforated pipe that distributes septic effluent into the corrugations created by the plastic core.
Primary Wastewater Treatment
The GSF Module is designed to manage the biomat and relieve the native soil of the burden of treatment and biomat development.
Aerobic bacteria can grow on the GSF Module’s geotextile fabric interface thanks to open-air channels within the module. This promotes oxygen absorption in the system.
The unique design of the GSF Module provides a large surface area for the biological treatment of contaminants and nutrients.
The top and side sections of the Eljen GSF Module are covered with anti-siltation geotextile fabric to prevent fines from migrating into the open channels.
Secondary Wastewater Treatment
As well as protecting the soil from compaction, Specified Sand acts as a filler, preventing cracks and crevices from appearing in the ground.
The filtered effluent drips into the Specified Sand layer, with precise grain size allowing unsaturated flow into the surrounding native soil.
The native soil serves as the final filtration layer and recharges the groundwater.
Specified Sand Layer
All Eljen GSF Systems must be installed using ASTM C33 sand that passes no more than 10% through a #100 sieve and no more than 5% through a #200 sieve to ensure that the system functions properly. This specification is the key to successful secondary treatment before the wastewater reenters the native soil.