The Enviro-Septic System was invented in the small northern New Hampshire town of Whitefield by Dave Presby. Presby, president of Presby Environmental, learned a long time ago that if he built an eco-system that cleaned the effluent before it got to the soil, the results were markedly better.
Geotextiles certainly helped!
To quote the technical description from the Presby Environmental website:
Treatment occurs in a perforated plastic pipe, a white bio-accelerator geotextile fabric along the bottom exterior surface, and a surrounding layer of plastic fiber mat and geotextile fabric.
Ridges in the pipe allow effluent to flow uninterrupted around the circumference and cool the liquid to ground temperature. Skimmer tabs at each perforation retain grease and suspended solids, protecting the outer layers from clogging.
The bio-accelerator filters additional solids, speeds treatment, facilitates quick startups, provides more surface area for bacterial growth, promotes even distribution, and protects outer layers and receiving surfaces from clogging. The surrounding mat of coarse fibers further filters the effluent as it passes into the outer geotextile layer and grows a protected bacterial surface.
The lightweight pipe is installed in ASTM C-33 sand, which wicks liquid from the geotextile fabric while transferring air to the microorganisms. The technology provides a large bacterial surface to break down solids, while an ample air supply and fluctuating liquid levels increase bacterial efficiency.