GREY WATER TREATMENT TANK TECHNOLOGY
A grey water treatment tank conditions grey water so that it may be more readily infiltrated into the subsurface soil. It does this by removing solids, biologically treating the solids and storing the sludge and scum produced with grey water. As grey water enters the treatment tank, suspended solids in the liquid sink to the bottom or rise to the surface and only the clarified effluent is discharged. The remaining solids and liquids in the tank are subjected to anaerobic decomposition by bacterial and natural processes. The end product of sludge and scum remains in the tank and needs to be removed periodically.
The sketch below is a grey water treatment tank used by the Alpine Club at several of their alpine huts. Solids are removed before the liquid is discharged, but decomposition is not intended to take place inside the barrel. The barrel and its contents are replaced by helicopter.
Precedent
Tasmania Cradle Huts
The huts were designed to have as little impact as possible on the fragile alpine environment, which includes glaciated landscapes and a number of threatened rare and endemic plant species. The huts can actually be easily dismantled and removed at any time. A sand filtering process is used to treat grey water from the kitchen and bathroom, which is then absorbed in trenches on site.