Description of Technology

The GST Leaching System (GST) is an adaptation of the stone leaching trench. This traditional leaching system has a removable form to accurately shape and construct leaching fingers along the sides of a central distribution channel. GST has direct stone to soil contact for enhanced longterm performance.

The GST leaching System can be installed in 37” and 62” widths and at 6”, 12”, 18”, 24”, 30” and 36” depths. The GST leaching system is placed on at least 2-inch deep bed of sand. Effluent is distributed into the System via at least 3-inch perforated distribution pipe (for gravity systems) set along the top of the system extending the entire GST length. Stone is placed around the distribution pipe, and filter fabric is placed over the system and distribution pipe.

GST may be used for disposal of wastewater effluent from a Title 5 septic tank or secondary treatment unit. GST replaces and provides alternatives to a conventional leaching system and alternatives to some of the design requirements of Title 5. The GST system can be installed in trench and bed configurations and function in a gravity and pressure distribution system configuration. In a pressure distribution configuration diffusers are installed over orifices.

Massachusetts Technology Approvals

Approval Type	General	Remedial	Provisional	Pilot
Secondary Treatment
Nitrogen Removal Credit
Phosphorus Removal Credit

Please check the Title 5 Innovative/Alternative Technology Approval Letters webpage at Massachusetts DEP for the most up-to-date information.

Test Center Reports & Data