Specifying a septic tank or sewage treatment plant depends on several factors, including: • Soil conditions for effluent distribution
• Population to be served
• Council and environmental agency policy
• Number of septic tanks already in the area
The most economical solution is to use a septic tank, but septic tank effluent normally has to discharge into an underground soakaway/distribution system. A "percolation test" has to be carried out on the soil to find out if it is suitable for this type of effluent and how long the soakaway system should be. If the soil fails the test then other treatment plant such as the CAP or SBR have to be considered as the effluent from these can be discharged directly into a watercourse, subject to approval from the environmental agencies.
Use the product selection flow chart on the right to determine which type of tank is suitable for your environment.
In all cases advice should be sought from the local authority Environmental Health Department. It may also be necessary to consult:
• The Environment Agency (EA - England and Wales)
• The Scottish Environment Protection Agency (SEPA - Scotland)
• The Environmental Protection Agency (EPA - Ireland)
• The Department of Environment (DoE NI) in Northern Ireland.
