Frequently Asked Questions 

A: A septic system is a subsurface wastewater treatment and disposal system. In most circumstances, a septic system will serve only one individual house or building. The sewage from the house enters the system through a building sewer and is treated before being discharged into the ground. Modern systems include a septic tank to retain solids, greases and fats, and a disposal field to allow the liquid (effluent) to flow into the ground.

A: A sand mound is a system in which the disposal field has been elevated above the original ground surface to account for a high-water table, shallow bedrock, or another type of site constraint. A mounded system will normally include a pump tank and pump to lift the effluent up to the raised disposal field.

A: No. Although a sand mound does include the pump and its associated electrical connections, a properly designed and installed sand mound is no more prone to failure than a conventional septic system.

A: This is the simplest type of subsurface wastewater treatment and disposal system. A cesspool is common for homes built prior to 1930. The system consists of a pit that has been constructed out of fieldstone or concrete block. Sewage enters the pit through the building sewer. The liquid level in the pit rises while water is added. The water level drops as water flows out of the cesspool and into the surrounding soil. Cesspools are normally quite deep, and the pressure from the water column within the pit forces water through the openings into the soil.

A: You should pump your septic tank every 2 - 3 years under normal circumstances. If you have a large family, you will want to pump the septic tank more often to prevent solids from flowing out of the tank and fouling the disposal field.

A: The primary function of the septic tank is to separate liquids from solids. Solids are retained in the tank after settling. Digestion of the solids occurs over time; however, the rate of solids accumulation exceeds the rate of solids digestion. Additionally, not all of the solids are digestible. Therefore, the solids level does rise over several years. A septic tank must be pumped periodically to prevent the solids level from reaching the outlet baffle where they are carried over to the disposal field.

A: A septic system is designed to treat domestic sewage generated through routine wastewater-producing activities (i.e. bathing, dishwashing, toilets use, etc.) Do not dispose of harsh chemicals such as pesticides, paint and paint cleaners, solvents, degreasers, etc. in the septic system. The liquid fraction of the wastewater is discharged into the ground. Some organic chemicals will flow untreated through the septic tank and the soil, thus contaminating the underlying groundwater. Do not dispose of condoms, feminine hygiene products, baby wipes, or other solid wastes in a septic system. These solids are not digestible and reduce the capacity of the septic tank.

A: When used at the recommended rate, household bleach does not produce a high enough residual concentration of chlorine to harm a septic system.

A: Digestion of the solids that accumulate within the septic tank is a naturally occurring process. The microbes that drive the digestion process are present in raw sewage at a high enough concentration that supplemental products are not normally necessary. However, adding commercially available products will not harm your system.

A: A baffle is an internal component of the septic tank. An inlet baffle directs all sewage towards the bottom of the tank. An outlet baffle prevents floating scum and grease from escaping the septic tank and accumulating in the disposal field.

A: Gray water is the portion of sanitary sewage that is not generated from toilets or urinals. This includes laundry wastewater, kitchen sinks, showers, etc. It is not unusual for homes built prior to the 1980s to have a separate septic system that handles the gray water.

A: Black water is the portion of sanitary sewage that is generated from toilets and urinals.

A: If the grass over your septic system is lush green and the soil is moist, you may have problems with your septic system. You should contact an expert to examine your system to isolate the cause of this condition. If the grass over the septic system is brown, you most likely do not have enough topsoil to support the lawn's root system.

A: Routine pumping of a septic tank should occur every 2 - 3 years. If you have followed this schedule, saved the maintenance receipts, and your next regular pump-out will occur during the time your house is on the market, there is no problem in having your septic tank pumped. However, if you have not followed a regular maintenance schedule and decide to pump your tank just before the sale of your home, it may raise a red flag.

If you are concerned about the condition of your septic system, it might make sense to have the system inspected by a reputable company before you put the house on the market. Minor repairs, if necessary, can then be performed in accordance with a permit issued by the Health Department. The recent repairs and the appropriate documentation may then become a selling feature for your property.

A: Powdered detergent comes out of solution and collects in the septic tank. Liquid detergents do not present this potential problem.

A: Contact a reputable excavation contractor or engineering firm with experience in troubleshooting and correcting septic system problems.