When getting a new septic installed there are several steps involved.  A site and soil evaluation must be carried out prior to installation as well as a Council Form 1 here in Queensland.  After this, the appropriate permits and approvals can be applied for.  Site survey findings that influence the design include things like:  available space, topography, intended purpose and perceived water use based on the size of the dwelling the system will service.

Why do I need a soil test before getting a septic system installed?

A soil test measures the water absorption rate of the soil, determines the ability of the soil to absorb wastewater and predicts the required size for the leach field. It also analyses the subterranean conditions and the level of the water table. 

Testing can also enable Tradesmen to modify the design or make changes to the building structure at the early stages of planning. Soil testing in the design phase saves money and time. It also prevents the septic system from breaking down due to poor soil drainage characteristics and saves you time and money on expensive repairs in the future.