ELJEN GSF from Enviro-STEP Technologies, sold here > Ontario


​Approved under BMEC Authorization 15-02-376, ELJEN GSF is the most passive, affordable and performing advanced treatment system of its kind. It combines treatment and dispersal with a lot of flexibility on the site. It can be used in larger applications in two configuration: Direct infiltration or surface discharge (where applicable).

​ELJEN GSF is a system developed for single dwelling as well as commercial and communal applications.

​The Eljen GSF System is a combined treatment and disposal technology providing a two-stage Bio-MattTM pre-treatment process, drastically improving effluent quality prior to recharging the aquifer (subsurface infiltration).

​The first stage of pre-treatment is provided within a proprietary simple and passive module consisting of successive layers of cuspated plastic core and Bio-MattTM fabric assembled together in a unique accordion shaped mat. This unique configuration offers very high treatment area and allows for effluent retention within the module where superior aerobic treatment is performed by the biomass attached to the fabric. This porous but dense textile matrix controls flow variations and fine particles filtration releasing only highly pretreated effluent to the specified sand layer under and on the sides on the modules. The alternating feeding and resting cycles allows the oxygen to penetrate deeply in the module to provide optimal oxidation conditions to degrade biological residues. The biosolids accumulation in the ELJEN GSF System is near zero and therefore offers superior life expectancy without risk of clogging. The modules come as a 600 mm wide by 1200 mm long and 175 mm thick mattresses that are laid on the soil surface in rows over the entire area of the receiving soil.

​The second stage of pre-treatment is provided by a layer of 150 mm of specific sand into which the effluent from the GSF modules drips slowly and supports unsaturated flow into the native soil. This Specified Sand and soil interface maintains soil structure, thereby maximizing the available absorption interface in the native soil. The combination of the high treatment level achieved in the module and the final filtration, polishing and dispersion in the specified sand layer eliminate risks of native soil clogging.

​With only 150 mm of sand, ELJEN was able to demonstrate that the pretreated effluent moves vertically and laterally in the sand layer to distances up the 15 feet from the module. These enhanced dispersal characteristics are very important in reducing the effective loading rate on the native soil and prevent water table mounding. The ELJEN GSF does not require any sand mantle since the effluent is already dispersed evenly on the entire infiltration surface. This procures a tremendous advantage in the configuration possibilities on the property.

​With its low sand profile and compact module, ELJEN GSF system has minimal or no visual impact on the property. The sand used with the ELJEN GSF is easy to find and is referred to as ASTM C33 concrete sand. We encourage installers and designers to send us your local sand pit sieve analysis for verification or download our easy sand verification tool.

​The ELJEN GSF modules can be configured in one or multiple treatment zone as long as the flow is distributed evenly. The modules can be put in straight lines or be curved to follow contour line, save a tree, etc. Please contact Enviro-STEP Technologies or any Ontario distributor to inquire about all the ELJEN GSF possibilities and advantages.

​ELJEN GSF has been used in hundreds of thousands of residential and commercial septic systems across the US and Canada. It is one of the only technologies tested according to an extended NSF standard 40 protocol covering a full 14 months period and including more than three consecutive months under cold weather conditions. Become one of the thousand ELJEN GSF user across North America and start enjoying real Onsite Peacefulness.

​You have a Drinking Water Treatment Device such as a Water Softener and you heard that all technologies are voiding the warranty if the backwash is sent to their system? Don’t worry, Enviro-STEP Technologies honors ELJEN GSF warranty even with the presence of a water softener backwash. Please call our technical support staff for details on how to beneficiate of this unique advantage in the market.
Enviro-STEP Technologies and its Ontario distribution network offers support and technical assistance to homeowner, designers, installers and regulators. The Complete design and sizing of the ELJEN GSF system is covered in the BMEC approval and the Ontario Design and Installation Manual. A design Worksheet is also available.

Our experts will answer your questions


  • 100% passive, advanced combined treatment and dispersal system
  • One of the most affordable technology available
  • No Sand Mantle Required
  • Tested for Canadian cold climate
  • No mechanical parts, no energy consumption
  • Over 150 000 systems installed



Performances du ELJEN GSF from Enviro-STEP Technologies, sold here > Ontario


Product Overview
Homeowners Manual