Septic tank
A septic tank is an underground chamber made of concrete, fiberglass or plastic through which domestic wastewater (sewage) flows for basic treatment. Settling and anaerobic processes reduce solids and organics, but the treatment efficiency is only moderate (referred to as "primary treatment"). Septic tank systems are a type of simple onsite sewage facility (OSSF). They can be used in areas that are not connected to a sewerage system, such as rural areas. The treated liquid effluent is commonly disposed in a septic drain field which provides further treatment. However, groundwater pollution may occur and can be a problem.
Lidcombe Hospital Precinct
The archaeological resource associated with the first septic tank constructed in Australia and the possible relationship between the irrigation system stormwater channel and the sewerage system has the potential to yield information about the development of the early sewerage system and its technical innovation. The remains of the septic tank itself are no longer within the hospital boundary, but pipes and channels and associated infrastructure are likely to be located in the Lidcombe Hospital Precinct. (The remains of the septic tank are in the University of Sydney Cumberland College campus).