GRAF UK supplies underground septic tanks for domestic, self-build, and rural property projects. Our septic tanks are manufactured from high-quality polyethylene, offering excellent durability and resistance to ground movement and corrosion. Lightweight yet robust, they are straightforward to install and suited to a wide range of site conditions. GRAF septic tanks work in conjunction with a drainage field (soakaway) to provide passive, low-maintenance treatment of household wastewater, an effective and reliable solution for properties off the mains sewer network. All GRAF tanks are manufactured from 100% recycled plastic and carry a 15-year warranty. Free UK mainland delivery is included as standard.