How a Septic System Works
Coppola Services, Inc.
Serving New York, New Jersey and Connecticut
A septic system is composed of two main components: a septic tank and an absorption area. Each has an integral function in the treatment and disposal of domestic wastewater resulting from laundry and bathing, kitchen wastes and body wastes. This relatively simple system of wastewater renovation can effectively remove disease-causing pathogens and chemical nutrients from domestic wastewater for the life of the home when it is properly designed, constructed, operated and maintained.
The Septic Tank
Septic tanks are required to be large enough to hold the sewage for approximately two days before it is discharged to the absorption area. For a single-family home with at least four bedrooms, the septic tank has to be at least 1,000 gallons in capacity. Add an additional 250 gallons of capacity for each bedroom over four.
Sewage, which enters the septic tank, is retained for a short period of time, during which it breaks down into scum, sludge and liquid effluent. Most solid matter will settle to the bottom as sludge while buoyant grease, fats and hair will float to the surface and form a scum layer. Between these two layers is the clear effluent, which drains into the absorption area. The solids in the septic tank will be digested and converted into gases by microorganisms such as bacteria.
The Absorption Area
Wastewater from the septic tank is passed on to the absorption area, also known as the drain field or leach field. The absorption area is a series of underground, perforated pipes, which overlay a bed of gravel approximately 12 inches in thickness. The perforated pipes, which are in individual trenches or grouped together into a single bed, distribute the wastewater throughout the entire area of the absorption area.
Near the bottom of the gravel bed of the absorption area, a slimy mass accumulates known as the biological clogging mat or biocrust. This biological layer, which occurs naturally in all properly designed, constructed and operated septic systems, consists of wastewater solids, microorganisms and the by-products of decomposition. The biological clogging layer represents a treatment medium for applied effluent in which larger microorganisms, such as bacteria, are filtered out along with suspended solids. Additionally, due to its reduced permeability, the biological clogging layer slows infiltration into the soil, and as such, equilibrates effluent throughout the entire absorption area. Within the soil, smaller microorganisms such as viruses become immobilized upon soil particles and die, while wastewater nutrients such as phosphorus and some forms of nitrogen are absorbed and become bound within the soil.
Recommended Operation and Maintenance Practices
Septic system owners are unique in that unlike areas served by regional sewerage systems, the septic system owner is solely responsible for the daily operation and maintenance of the wastewater treatment and disposal system. By adhering to simple and straightforward guidelines, the septic system owner can ensure years of trouble-free operation with a minimal degree of maintenance.
Contact Coppola Services
If you have questions or concerns about your septic system, give us a call at 1-800-274-6279 or use our quick contact form to reach us online.