What is an On-Site Subsurface Sewage Disposal System (Septic System)?
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A septic system is an assemblage of structures and materials that form a pathway for the removal domestic wastes from a building in such a manner as to protect public health and the environment. A typical septic system has four main components:
A pipe from the home. The pipe that leads from the building served to the septic tank simply removes the sewage to the septic tank.
A septic tank. The septic tank is where primary treatment of the effluent is conducted. Two very important processes occur at this stage. The first involves the separation of solids and greases from liquids, during this process the solids settled to the bottom of the tank and oils and greases rise to the top of the tank. The second process is the partial decomposition of solid materials resting in the tank.
The septic tank is separated into two compartments (see image on the right), the processes happen in the first compartment and the second compartment then receives only liquids. it is these liquids that are in turn transferred to the leaching area for remediation in the soil.
A Note on plastic tanks: While plastic tanks can be hand-carried to inaccessible locations and are preferable in some situations, such tanks should not be used in areas of high ground water because they are light weight and tend to float, particularly when the liquid level is low during cleaning.
A drain field (also known as leach fields, leaching pits, leaching beds, or leaching area). As the sewage effluent exits the septic tank, it is usually discharged into a distribution box that either evenly distributes the effluent into the entire leaching area or (in the case of a septic system on a hill) discharges the effluent to one trench at a time. On occasion the drain field may be so small that a distribution box is not necessary.
Drain fields vary in construction, shape, and size but all exhibit one characteristic that makes them drain fields, they are open systems which allow the effluent to seep into the soil. As the effluent is absorbed by the soil, additional effluent is pushed into the drain fields by the new wastewater entering the tank.
The Soil. Secondary, and in the case of a septic systems, final treatment occurs in the soil. This is where the soil microbes digest or remove most contaminants from wastewater before it eventually reaches groundwater.
Maintaining an on-site sewage disposal system is important for several reason. The first and most important reason is the threat to public health. Wastewater coming from a home can carry pathogenic organisms that can transmit disease to humans and other animals. The wastewater can also contain organic matter that can cause odor and nuisance problems to the homeowner as well as neighbors.
Another reason for maintaining a on-site sewage disposal system is financial. The average cost of replacing a septic system within our district is anywhere from $15,000 to $20,000. This number varies by contractor and the extent of the replacement.
Failing septic systems are expensive to repair or replace, and poor maintenance is often the culprit. Having your septic system inspected regularly is a bargain when you consider the cost of replacing the entire system. Your system will need pumping depending on how many people live in the house and the size of the system. An unusable septic system or one in disrepair will lower your property value and could pose a legal liability.
Pump and inspect on a routine basis. You should have a typical septic system pumped and inspected at least every 2-3 years by a licensed septic contractor. Your contractor should inspect for leaks and look at the scum and sludge layers in your septic tank. In the State of Connecticut, outlet filters are now being installed in tanks. The contractor must remove and clean this outlet filter as part of the pumping and inspection.
Four major factors influence the frequency of pumping: the number of people in your household, the amount of wastewater generated (based on the number of people in the household and the amount of water used), the volume of solids in the wastewater (for example, using a garbage disposal increases the amount of solids), and septic tank size.
SEPTIC ADDITIVES: Some makers of septic tank additives claim that their products break down the sludge in septic tanks so the tanks never need to be pumped. In the State of Connecticut we recommend against using such additives. Septic tanks, as part of their routine operation, already contain microbes needed for effective treatment. Therefore, additional additives are unnecessary and may actually impede the operation of the system by transporting sewage particles from the septic tank to the drain fields. Once in the drain fields those particles will promote clogging of infiltrative surfaces. Periodic pumping is the best way to ensure that septic systems work properly and provide many years of life long service. Whether you use these additives or not, don't be mislead, every septic tank requires periodic pumping.
Avoiding Problems With An On-site Sewage Disposal System
The following are simple things you can do as a homeowner to avoid problems with your septic system or even an expensive septic system repair:
- Do not allow excess amounts of fat and grease to enter the system, they can congeal and cause obstructions. In conjunction with this, it is not advisable to install a garbage disposal in the kitchen sink since it would tend to promote the disposal of products high in fats and greases. If a disposal unit has already been installed its usage should be limited.
- Do not dispose of household cleaning fluids down the drain and use chlorine bleaches and disinfectants sparingly.
- Do not dispose of toxic chemicals down any drain. Do not dispose of any non-biodegradable substances or objects, such as cigarette butts, disposable diapers, feminine products (particularly, tampons). Do not dispose of the backwash from water softening or other water treatment systems to the septic system. This is a Public Health Code regulated prohibition. Do not run multiple "full" loads when using a washing machine or dishwasher. Try to stagger use (i.e.., Do not run five or six loads on Saturday and none the other days). Do not run water continuously while rinsing dishes, thawing frozen foods or, shaving. Consider limiting toilet flushes or retrofit with low flush units. Do not connect any "clear water" sources, such as footing and foundation sump pumps to the sewage system. Keep accurate records about the location and cleaning of the system in a permanent house file so this information can be passed on to the next owner. Facilitate the pumping process by raising the clean out manhole of the septic tank to within 6" to 12" of the surface of the ground.
- Set up and adhere to a sound system of inspection and cleaning.
- Check for faucet leaks, etc. ...it is estimated that one leaky faucet can waste as much as 700 gallons of water a year. -If possible, determine the existing size of leaching system (your local health department may be assistance in this regard). From that information a determination can be made as to the amount of daily flow a well maintained system of that size could handle. Once that limit has been set it is important that it is not exceeded on a consistent basis.
- Educate your family on the proper use of the system.
Back washing softener regenerate to a septic system is specifically prohibited by the CT Public Health Code Technical Standards for Subsurface Sewage Disposal systems. The homeowner is usually unaware of the prohibition however, and it often happens that such backwash discharges are plumbed to the septic system, potentially leading to the following problems:
- hydraulic overloading of marginally sized septic systems,
- spalling of cement in concrete septic tanks, baffles, drywells and D-boxes, due to the introduction of salt or potassium chloride contained in the backwash discharge, and
- sludge buildup in the leaching system when significant levels of iron and manganese are present in the raw water, possibly leading to leaching field failure.
- groundwater contamination
Back washing of a softener to a septic system is specifically prohibited in the CT Public Health Code section 19-13-B103 and in the Technical Standards for Subsurface Sewage Disposal Systems. Discharging the backwash to a separate dedicated system is a viable option and is allowed under the authority of the CT DEP, pursuant to Section 22a-430 of the CT General Statutes.
Therefore, in order to protect the septic system and meet both DPH and DEP requirements, the North Central District Health Department requires that the discharge of these dedicated systems be directed to a separate leaching area capable of receiving the amount of wastewater discharged by the softening system. The leaching area usually consists of a 12-16 feet of plastic infiltrators installed in stone. The system must be greater than seventy five (75) feet away from the well and twenty five (25) feet away from any portion of the septic system. This separating distance will avoid contamination of the drinking water supply and the overloading of the septic leaching system.
While the construction of these dedicated systems are not issued permits and are not regulated by this office the well and septic system are. So in an effort to meet DPH & DEP requirements but at the same time protect your septic system and well, we highly recommend that you contract with a licensed contractor to install the system for you or contact our office for instructions on doing so. In any event, our office must be notified to ensure proper setback requirements to the well and septic are met.
If you are having problems with your current septic system the first thing to do is contact a licensed septic professional in your area. Many problems such as clogged or crushed pipes, clogged outlet filters, etc. can be easily corrected with a simple repair that can be done by your licensed septic contractor. In any event a licensed septic contractor will evaluate your septic system properly and complete your repairs in accordance with the public health code.
If after your septic system evaluation, you find that the repairs needed will be extensive and costly, our office highly recommends that you consult with additional septic contractors. Acquire price quotes from at least 3 contractors and while our policy is to not recommend any one contractor over another we can certainly answer your general questions about contractors.
If you find that you'll have to repair of replace your septic system, the procedure for this is as follows:
- Step 1 - Contact and Contract a licensed septic contractor. A good septic contractor will help explain and guide you through the requirements of the health department and the Public Health Code.
- Step 2 - Either yourself or your licensed septic contractor will fill out the proper forms with our office to initiate the repair or replacement of the system.
- Step 3 - If a simple repair is necessary, the contractor will submit plans for the repair along with the applications. The contractor will then receive a permit to conduct the simple repair and will do so. Upon completing the repairs the contractor will call for an inspection at which time our office will inspect and approve the repairs.
- Step 3B - If a more complicated repair or replacement of the system is necessary, the next step would be to find a "Code Complying Area (reserve area)" for the replacement. In this case, the contractor will submit an application for a soil test instead of a repair plan and a soil test will be conducted on the property. A soil test involves digging test pits on the property (usually with a back hoe) and evaluating the soils. The test pits can be anywhere from 4-10 feet deep but will be filled immediately after the evaluation of the soils are complete. During the soil evaluation a Percolation Test also known as a "Perc Test" will also be performed.
- Step 4 - Once the soils have been evaluated our office will inform the septic contractor of all pertinent information the contractor needs to design a replacement system for you. The contractor will then design the replacement and submit the plans to our office for approval as in step 3 for a simple repair. However, in extreme and very complicated cases, the septic contractor may refer the design part of the replacement septic system to a licensed engineer. Due to the complicated nature of those designs, our office also reserves the authority to require an engineer if the contractor does not refer to one and cannot demonstrate the knowledge required to design a complicated plan.
- Step 5 - Once the plans for the replacement have been submitted and approved, the contractor will be issued the proper permits for the work and the installation will begin.
- Step 6 - Lastly, whether it's a simple repair as in step 3 or a replacement as in step 3b, our office will inspect the final work for compliance with the public health code and approve the replacement system.