My company recently had a presentation done on septic systems: how they work, new regulations, and other information that we, as REALTORS^®, should know. I thought, then, that it might be good to refresh all our memories on how an On-Site Wastewater Disposal System functions.

The following information was taken from DNREC's web site where you can find all the information you want on Septic systems.

What are they? On-site wastewater disposal systems are water treatment facilities located within your property boundaries that collect, treat and dispose of wastewater. They differ from municipal wastewater treatment facilities which receive wastewaters from other locations for treatment. The on-site wastewater disposal system can consist of several components: septic tank, distribution box, dosing chamber and drainfield. If properly maintained, a disposal system can last 15 to 20 years.

What is their purpose? The purpose of the septic tank is to collect and partially treat household wastewater. In the tank, solids separate from the liquids and bacteria begins to breakdown the wastes. Approximately 60 percent of the solids are broken down by the bacteria into liquid and gas. During the two-to-three day treatment period the lighter-than-water solids such as greases, oils and toilet paper float to the top and form a scum layer. The solids, which are heavier than water, sink to the bottom forming sludge. The cloudy water in between is known as effluent.

How do they work? The processes in a septic tank take place anaerobically, which means without the presence of oxygen. The gas produced is discharged through the plumbing vent system on the roof of the house. Methane and hydrogen sulfide are gases produced through these natural processes. They are extremely dangerous. You should exercise extreme care when inspecting or looking into your tank.

The final treatment step for the effluent, as it returns to the groundwater, involves the drainfield. The drainfield may be referred to as a soil absorption system, a leach field or a disposal field. The drainfield is a series of perforated pipes placed in either a gravel-filled trench or bed, or placed in gravel-less chambers to evenly distribute the effluent. The wastewater slowly trickles through these materials and into the soil beneath. Soil bacteria breakdown the effluent aerobically, which means with the presence of oxygen.

As the effluent seeps into the soil and approaches the natural groundwater it is purified by other soil components in conjunction with the bacteria. Toxins, viruses and other pollutants are removed from the wastewater. Clay particles located in the soil chemically attract and hold sewage nutrients (phosphates and nitrates), heavy metals and disease-carrying organisms. However, chemical additives, paint, grease, fats or thinners will kill the bacteria and clog the drainfield, contaminating the groundwater. Over time, these products can render your drainfield ineffective.

Hope this information is helpful to you. See you next week!
Ronnie REALTOR^®

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