The BOD factor

If you are not connected to mains drainage you have three choices.

A basic septic tank only provides settlement for sewage solids. The liquid overflow requires further biological treatment in a suitably designed, correctly situated drainage field.

A super septic tank pumps air (including oxygen) through sewage which substantially reduces the pollution and smell content of the overflow.

A tank with integral treatment kit provides both settlement and biological treatment in a single packaged unit. This produces a far superior treated effluent.

	Sewage from the house. BOD factor of 300 or more.
	Septic tank or treatment unit. Stores solids for collection by tanker.
	Overflow. Lowest BOD factor means least health hazard