Recovering Failed or Failing Drain (Leach) Fields


Recovering failed or failing drain (leach) fields. A failed or failing drain (leach) field is caused by clogging of the biomat in the trenches of the field. Two things need to occur to correct the problem: stop adding organic matter into the field, and introduce dissolved oxygen into the wastewater entering the field.


A septic tank aerated effluent filter has proven that it can rejuvenate or recover a drain (leach) field that has failed due to a clogged biomat that has sealed off the available receiving soil from the incoming wastewater.


By filtering, consuming, and introducing air into the wastewater prior to entering the field [thus completing the integrated, Fixed-film Activated Sludge Treatment (FAST®) process], the RetroFAST® septic system enhancement prolongs the life of the entire septic system.



Independent Testing of Performance


The RetroFAST® system has been independently tested and approved by the EPA/ETV program as administered by the US Environmental Protection Agency that are recognized by the Standards Council of Canada. The RetroFAST® is a septic tank aerated effluent filter (STAEF)



How it Works


The system enhances an existing septic tank with the same design, performance standards and specifications as the proven MicroFAST® series of systems. Being attached to the final effluent outlet pipe of the septic tank, the septic tank retains its main function and retention time for the separation of liquids from solids The system provides an engineered area for treatment without disturbing the function of the septic tank.


The septic tank effluent can only exit the tank through the pre-engineered aerated media and outlet pipe. The system provides a significant reduction of the organic matter from entering the drain (leach) field using 2 means. One of the means is by filtering out drain field clogging material such as hair and paper products. The other means is by aerating the pre-engineered media and establishing an internal biological activity to digest the organic matter.


The aeration is achieved with the use of an external air blower that in addition to activating the sewage digestion process in the media also introduces dissolved oxygen (DO) into the wastewater effluent entering the drain (leach) field. The DO will breakdown any existing clogging biomat in the drain (leach) field and allowing for the wastewater to enter the soil as before.


For detailed information, download the specifications. [704.62kB]



How it is Installed


It is installed into an existing suitable septic tank or placed in a separate tank after the existing septic tank.


Video showing a RetroFAST installation.See how RetroFAST® is installed. (0:23)

Recovering failed or failing drain (leach) fields.

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