Septic Systems
From Swikipedia
Introduction
Septic systems are used to treat household sewage and wastewater by allowing the solids to decompose and settle in a tank, then letting the liquid be absorbed by the soil in a drainage field. Septic systems are normally used in home construction only when a sewer line is not available. They generally serve as an On-Site Sewage Facility (OSSF).
Brief Description
The term "septic" refers to the anaerobic bacterial environment that develops in the tank and which decomposes or mineralizes the waste discharged into the tank. Septic tanks can be coupled with other on-site wastewater treatment units such as bio-filters or aerobic systems involving artificial forced aeration.
Types of Septic Systems:
It is generally the site and the soil conditions which determine which of the two septic systems should be installed, ‘Conventional’ or ‘Alternative’ type.
The conventional systems include the gravity system (a system which uses gravity to move effluent through the septic tank and into the drain-field) and the pressure distribution system (which has a pump that distributes effluent throughout the drain-field at the same time. It is used in most new systems because it makes better use of the entire drain-field).
The alternative types of septic systems include:
Aerobic Treatment Unit (ATU) which uses oxygen to break down solids, producing cleaner wastewater than conventional types. It is often used in environmentally sensitive areas where effluent requires more treatment before entering the drain-field.
Mound System which is installed when minimal soil is available for treatment, drain-field is raised above ground level.
Sand Filter System which has a sand filtering system and pump to treat and disburse effluent, and is used when minimal soil is available for treatment.
References:
http://cyberparent.com/green-building/glossary/index.htm
