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A conventional septic system is comprised of three parts. The first is the conventional anaerobic (without oxygen) septic tank that receives the solid and liquid waste (called influent) from the house or business that’s connected to it. The second is the disposal field that receives liquid waste (called effluent) from the septic tank. The effluent is distributed throughout the disposal field so that it can be absorbed into the surrounding soils. The third is the soil that purifies the effluent. The way the three parts operate is simple and easy to understand. Within the residence or business, solid waste is put into water so gravity can move it away and into the septic tank. The conventional septic tank is designed to remove the majority of these solids from the water used to carry it to the septic tank. This is accomplished by retaining the influent for several days in the septic tank to allow separation of floatable solids (scum) and sinking solids (sludge) from one another. Intestinal bacteria from human bodily wastes survive within the conventional septic tank and there secrete enzymes that assist in breaking down the solid wastes into these two forms. By this method, 70% to 90% of the solids that were originally put into water are removed and contained within the septic tank. Over time, these solids build up within the septic tank and have to be removed by pumping and disposed of off site. Typically this means taking the contents or the septic tank (septage) to the local municipal wastewater plant for treatment (digestion) and disposal. The clarified liquid (effluent) between the two forms of solids, then over flows out of the septic tank as new influent comes in, and is piped to a disposal field. The disposal field can be of many designs and constructions. Most typical is the leach line, though all disposal fields have the same function. This function is to expose the liquid effluent to aerobic soils (with oxygen) that can absorb it. Within the aerobic portions of the soil, there is an abundant community of aerobic microbes, including many species of bacteria that digest the remaining organic matter, purify and recycle the liquid back into the environment. The part of a conventional septic system that fails is the disposal field.

WHAT IS A CONVENTIONAL SEPTIC SYSTEM? A septic system is designed to be either conventional, without air added to the liquid, or aerobic, with air added to the liquid. A septic system is comprised of three parts. The first part is the tank. The second part is the disposal field. The third part is the soil. The purpose of the three parts is simple and easy to understand. The purpose of the tank is to remove most of the solid waste from the water. Conventional septic tanks, without air added to the liquid, simply store the solid waste until you remove the solid waste by pumping the tank. Aerobic tanks, with air added to the liquid, grow oxygen breathing bacteria that remove solid waste by digesting it. The purpose of the disposal field is to spread the liquid from the tank over a large underground area of soil, so the liquid can be absorbed or soaked up by the soil. The purpose of the soil is to do the final treatment or purify the liquid from the tank. Large numbers of tiny life forms called microbes live in the soil. These microbes eat the remaining waste in the liquid. This purifies the liquid so it is safe for humans and will not pollute drinking water or the environment.

SEPTIC SYSTEM FAILURE If a house is not connected to a sewer plant, the house has a septic system. All human waste from the toilets and other waste material from the house go into the septic tank. In human wastes are huge numbers of microbes that are part of our body’s system to digest food. In the septic tank these microbes continue to live outside of our bodies. They grow and multiply in the septic tank and eventually leave the tank and travel to the disposal field. In the disposal field they continue to survive, grow and multiply. Over time, they form a huge colony over all the soil surfaces. In order to survive, they coat themselves with a thick slime called Biomat. After years of using a septic system, the Biomat slime gets thicker. Eventually, the Biomat slime becomes thick enough that liquid leaving the septic tank cannot get through the Biomat slime as fast as liquid is put into the septic tank. The septic system backs up and fails. The septic industry calls this “Biomat clogging” of the disposal field soil. Failure is: liquid surfacing or soft spots in the soil over the disposal field; liquid or soft spots over the septic tank; slow draining plumbing fixtures; strange noises and gurgling in the plumbing lines; complete backup of the plumbing in the house; septic odors in or around the house. Biomat slime is the cause of 95% of septic system failures.

EPA Clogging Graphic.

Septic problems are biological. Solutions are biological. The following primer on the biology of septic system failure describes how the PIRANA, a bacterial inoculator / generator, can solve your septic problems. Septic / Leach Field Theory 1. Septic Tank Function - Conventional septic tanks are anaerobic (without air) and designed to separate organic solids, (food for bacteria) in the effluent through settling (sludge) and flotation (scum). Some solids are liquefied by anaerobic bacteria. Only liquid effluent should flow to the leach field. 2. Leach Field Function - Leach fields are designed to move the septic liquid into the aerobic portion of the soil where abundant natural bacteria, fungi, protozoans, worms, insects, etc. can digest the organic material, leaving clean water to pass into the aquifer. The Real World 1. Septic Tank - We continuously inoculate our septic tanks with anaerobic intestinal bacteria when we flush our toilets. They are the primary bacteria in conventional septic systems. These bacteria are some of the weakest in nature. If they were not weak, they would literally eat us. Nature selects for strong bacteria through competition and adverse conditions. These intestinal bacteria are weak because they are selective in their food source (what we eat), they have little or no competition from other microorganisms, they live in a nearly perfect and constant 98 degree temperature in our intestines. To survive in our intestines, these bacteria protect themselves by secreting a heavy mucous coating. These weak intestinal bacteria cannot digest the organic solids in a conventional septic tank. The undigested organic material, pass out to the leach field in dissolved form. Solids build up in the tank, odors form, scum and sludge are created. Because of this build up, tanks need frequent pumping. 2. Leach Field - These intestinal bacteria continue to secrete mucous, or slime, as they collect on the soil surfaces of a leach trench. This process plugs the soil pores with slime, commonly referred to as “Biomat”. Liquid from the septic tank cannot pass into the aerated soil where it can be purified. The trenches fill with effluent and the leach field fails. Septic waste surfaces over the leach field or it backs up into the house. The homeowner has a crisis. The EPA estimates that 95% of septic system failures (over a million homes a year) are caused by “Biomat” clogging.

The PIRANA Solution 1. Septic Tank - By installing the PIRANA into a single volume tank, or chamber of a septic tank, a blend of natural, powerful PIRANA-BLEND soil bacteria is continuously inoculated into the septic liquid. These powerful soil bacteria replace the weak intestinal bacteria and flow out of the tank, suspended in the effluent, and inoculate the soil of the disposal field. The liquid effluent in a tank or chamber is circulated through the PIRANA at a rate of 30,000 gallons a day. This circulating effluent passes over 150 ft2 of surface area within the PIRANA, where a dense colony of these powerful soil bacteria becomes attached. As the effluent passes over the attached bacteria, the bacteria multiply in response to, and digest, any additional food. Countless bacteria become suspended in the effluent and flow out to the disposal field. The digestion is so complete that regular pumping is no longer necessary. 2. Leach Field - The PIRANA treated septic liquid is now very low in organic food material, starving the resident slime producing anaerobic bacteria that caused the “Biomat” clogging. The slime becomes food for the powerful soil bacteria generated by the PIRANA. The PIRANA process quickly opens the soil surfaces of the leach trench so septic liquid can pass into the aerobic soil. The powerful soil bacteria in the septic liquid pass into the soil pores, their natural environment. They colonize the soil of the leach field and keep it open. “Biomat” clogging cannot reoccur as long as the PIRANA is operated following manufactures guidelines.

AND ♦PIRANA restores failed septic disposal systems ♦PIRANA minimizes septic tank pumping ♦PIRANA eliminates nitrate loading to the groundwater ♦PIRANA uses only 40 watts of power, literally pennies a day to operate ♦PIRANA is quickly installed with no damage to landscaping ♦PIRANA is the lowest cost of any treatment option

For additional information contact Pirana: West End tel: 445-4123/ 3336-0406 / email:

Piraña Document  

Complete septic system information

Piraña Document  

Complete septic system information