If your county health department inspects Septic Systems, I recommend you have them preform your system inspection and dye test. They can research if the septic system is properly permitted, we do not check permits.
Many times county health departments so not have the manpower to test or the home is not inhabited at the time needed. This can create a barrier to closing, many mortgage companies will not close a loan without the septic inspection. You cannot inhabit the home until after you close, but you cannot close without a septic inspection and the health department (if they inspect) will not inspect until the home has been inhabited. A Real “Catch 22″
That is where we come in, we will inspect the septic system, and perform an inspection with a functional dye test. We need to run the water long enough to fill the tank and cause it to drain into the leach bed. We return the next day and inspect for leakage and to insure grey water is being drained into the sanitary septic system. With the aerator septic system we insure there are not broken pipes leaking visible affluent into the yard and insure the chlorine system is operational.
Standard Leach Field Septic System
Septic drain fields, also called leach fields or leach drains are used to remove contaminants and impurities from the liquid that emerges from the septic tank. A septic tank, the septic drain field, and the associated piping compose a complete septic system. The septic drain field is effective for disposal of organic materials readily catabolized by a microbial ecosystem. The drain field typically consists of an arrangement of trenches containing perforated pipes and porous material (often gravel) covered by a layer of soil to prevent animals and surface runoff from reaching the wastewater distributed within those trenches. Primary design considerations are hydraulic for the volume of wastewater requiring disposal and catabolic for the long-term biochemical oxygen demand of that wastewater.
Many health departments require a percolation test (“perc” test) to establish suitability of drain field soil to receive septic tank effluent. An engineer or licensed designer may be required to work with the local governing agency to design a system that conforms to these criteria.
Wastewater from toilets is assumed to contain bacteria and viruses capable of causing disease. Disinfection methods used prior to surface disposal of municipal sewage cannot be used with septic tanks because disinfection would prevent wastewater treatment by killing the septic tank and soil ecosystems catabolizing the putrescible contents of the wastewater. A properly functioning drain field holds and deactivates pathogens before they leave the drain field soil.
The goal of percolation testing is to ensure the soil is permeable enough for septic tank effluent to percolate away from the drain field, but fine grained enough to filter out pathogenic bacteria and viruses before they travel far enough to reach a water well or surface water supply. Coarse soils – sand and gravel – can transmit wastewater away from the drain field before pathogens are destroyed. Silt and clay effectively filter out pathogens but allow very limited wastewater flow rates. Percolation tests measure the rate at which clean water disperses through a disposal trench into the soil. Several factors may reduce observed percolation rates when the drain field receives anoxic septic tank effluent:
Microbial colonies catabolizing soluble organic compounds from the septic tank effluent will adhere to soil particles and reduce the interstitial area available for water flow between soil particles. These colonies tend to form a low-permeability biofilm of gelatinous slime at the soil interface of the disposal trench.
Insoluble particles small enough to be carried through the septic tank will accumulate at the soil interface of the disposal trench; non-biodegradable particles like mineral soil from laundry or vegetable washing, or bone and eggshell fragments from garbage disposals will remain to fill interstitial areas formerly available for water flow out of the trench.
Cooking fats or petroleum products emulsified by detergents or dissolved by solvents can flow through prior to anaerobic liquifaction when septic tank volume is too small to offer adequate residence time, and may congeal as a hydrophobic layer on the soil interface of the disposal trench.
Rising groundwater levels may reduce the available hydraulic head (or vertical distance) causing gravitational water flow away from the disposal trench. Effluent initially flowing downward from the disposal trench ultimately encounters groundwater or impermeable rock or clay requiring a directional shift to horizontal movement away from the drain field. A certain vertical distance is required between the effluent level in the disposal trench and the water level where the effluent is leaving the drain field for gravitational force to overcome viscous frictional forces resisting flow through porous soil. Effluent levels in the vicinity of the drain field will appear to rise toward the ground surface to preserve that vertical distance difference if groundwater levels surrounding the drain field approach the level of effluent in the disposal trench.
Frozen ground may seasonally reduce the cross-sectional area available for flow or evaporation.
Aerator AEROBIC TREATMENT SYSTEMS
An aerobic treatment system or ATS, often called (incorrectly) an aerobic septic system is a small scale sewage treatment system similar to a septic tank system, but which uses an aerobic process for digestion rather than just the anaerobic process used in septic systems. These systems are commonly found in rural areas where public sewers are not available, and may be used for a single residence or for a small group of homes.
Unlike the traditional septic system, the aerobic treatment system produces a high quality secondary effluent, which can be sterilized and used for surface irrigation. This allows much greater flexibility in the placement of the leach field, as well as cutting the required size of the leach field by as much as half.
The ATS process generally consists of the following phases:
Pre-treatment stage to remove large solids and other undesirable substances from the wastewater; this stage acts much like a septic system, and an ATS may be added to an existing septic tank to further process the primary effluent.
Aeration stage, where the aerobic bacteria digest the biological wastes in the wastewater.
Settling stage to allow any undigested solids to settle. This forms a sludge which must be periodically removed from the system.
Disinfecting stage, where chlorine or similar disinfectant is mixed with the water, to produce an antiseptic output.
The disinfecting stage is optional, and is used where a sterile effluent is required, such as cases where the effluent is distributed above ground. The disinfectant typically used is tablets of calcium hypochlorite, which are specially made for waste treatment systems. Unlike the chlorine tablets used in swimming pools, which is stabilized for resistance to breakdown in ultraviolet light, the tablets used in waste treatment systems is intended to break down quickly in sunlight. Stabilized forms of chlorine will persist after the effluent is dispersed, and can kill off plants in the leach field.
Since the ATS contains a living ecosystem of microbes to digest the waste products in the water, excessive amounts of items such as bleach or antibiotics can damage the ATS environment and reduce treatment effectiveness. Non-digestible items should also be avoided, as they will build up in the system and require more frequent sludge removal.