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Bacterial augmentation, an effective next step before septic system replacement
It can be a home or business owner’s worst nightmare—after their septic system fails to respond to pumping and other short-term remedies, the septic company appears to have no choice but to recommend a complete system replacement, often costing into the tens of thousands of dollars.
Is there a solution, besides pumping or other current bacterial or chemical remedies, that offers the system owner real relief without having to resort to system replacement?
The answer is “yes”—a new technology that remediates the soil absorption system through bacterial augmentation.
The most common reason for the failure of a septic system is accumulated organic material in the leaching field or pit. This build-up prevents liquid from filtering and can eventually render the system impermeable. Once the soil absorption system fails, consumers and professionals often resort to septic system replacement—
especially if they’ve already tried conventional chemical and/or bacterial treatments. But there’s another solution that may be a win-win for both the consumer and the pumper, enabling the pumping company to offer the home or business owner an effective treatment program requiring periodic maintenance without having to resort to excavation and system replacement.
Bacterial augmentation works
Some of the traditional technologies include chemical treatment and/or bacterial augmentation, but both of these methods in their current forms have proven less than effective over the long term. Oxidizing chemicals can improve the permeability of the leaching field but, over time, the biological and organic material can build up again and the problem returns. Biological treatments such as the addition of powders or solutions containing specific bacteria can improve the degradation of organic sediments, but the organisms have limited performance in environments with no oxygen present, which is typically the case with septic systems.
A third alternative, using pressurized air to break up a clogged leaching area has proven to be controversial and in some cases, even illegal when untreated effluent bypasses the filtration step. A fourth, more effective method has recently been developed that maximizes aerobic bacterial efficiency via the continuous injection of oxygen.
The key ingredient
Most biological treatments are ineffective because often the wrong microbial combination is used and, in many cases, lack of oxygen causes the bacteria to die before effective remediation is accomplished. These treatments usually result in the regeneration of the clogging biomass. The trick is to provide both the right combination of bacteria and oxygen in a continuous manner to enable the hungry microbes to live, eat and multiply. This requires a system that enables the liquid to circulate continuously over an engineered media. The media provides a substrate for the bacteria to attach and grow.
In addition, supplemental bacteria can be added to the system to further enhance degradation of organic material. The injected bacteria are in liquid form and are actively growing, in comparison to other dry or powdered products where the bacteria are dormant and require some time to grow.
Environmental Operating Solutions developed a technology for both residential and commercial use. For homeowners, a computer-regulated controller provides continuous delivery of oxygen and calibrated volumes of specially formulated bacteria into the leaching component. The continuous injection of oxygen and bacteria biologically degrades the clogging biomass layer and restores normal function to the system in a short period of time. Critical to the performance efficiency of the technology is the microbial formulation—called a bacterial “suite”—which can be created to reduce total suspended solids; fats, oils and grease (FOG); nitrogen; biochemical oxygen demand; and chemical oxygen demand. These naturally occurring bacteria are continuously delivered into the leaching component via a pumping system regulated by the controller installed adjacent to the septic system, either above ground in a discreet location with an accessible power source or in a subsurface container for added protection and insulation. The advantage of dosing the leaching component with bacteria is to minimize any inhibitory effects due to high temperatures or toxic chemicals.
Bacterial augmentation is also proving to be a cost effective alternative for the food service industry, effectively reducing FOG concentrations that can clog soil absorption systems or sewer lines and lead to costly restaurant closure and complete replacement of the leaching system.
Similar to the residential system, the FOG system works to break down FOG by injecting appropriate bacteria and oxygen into targeted areas of the commercial septic system. A technician takes samples at various points within the problematic septic system and gathers information on flows, temperatures, detergents, kitchen practices, hours of operation and peak flows.
All of these data are analyzed and used to determine where to place the controller in the system, and the appropriate number of components required for introduction of the bacteria and oxygen at key locations. Typical areas requiring a bacterial augmentation mechanism (BAM) include the grease trap, settling tank, and leaching system. Often, by incorporating the BAM system as far upstream as possible (at the grease trap, for example), the rejuvenating affects are compounded as the bacteria rich liquid moves downstream and degrades the FOG material as it nears the leaching pit or field.
Good news for owners
With septic system replacement costs
running anywhere from ten to as much as $50,000, a system remediation solution such
as bacterial augmentation is a welcome alternative both for the home and business owner. Installation of both the residential and commercial systems doesn’t require much more than the ability to dig small trenches, install relatively simple controllers and components, and monitor the system on a periodic basis to renew bacterial suites and check on system functions.
This is a useful product for the pump industry because it provides an opportunity for additional revenues after pumping efforts have been exhausted.