Learning Center

Decentralized wastewater treatment, or septic systems, refers to permanent systems that treat wastewater at or near its source, without connection to sewer systems. The economic and environmental advantages of septic systems prompt many homes and communities to make the switch when modifying, replacing, or expanding their wastewater treatment systems. Through proper design, maintenance, and operation, septic systems provide a compact and powerful form of treatment for even highly sensitive sites.

The basic functionality of a septic system follow three general steps: Collection, Treatment, and Dispersal.

1. COLLECTION

The waste and wastewater generated by a domestic or commercial building is initially collected by a buried septic tank through a pipe network. A septic tank is the most common pretreatment unit for onsite wastewater systems.

2. TREATMENT

Treatment of wastewater occurs through various processes depending on the system. The septic tank is responsible for removing settleable solids, oils, greases, and floating debris, which are stored in sludge and scum layers and digested by acid-forming microorganisms. The scope of wastewater treatment is to create the proper environment and workspace for the microorganisms. We want to create an environment that is conducive to productive microbial growth, and provide media for the microbial colonies to populate and effectively digest organics. Generated gasses from digestion are vented back through the building plumbing stack, continuously sealed in water tight containers that eliminate any unwanted smells. Effluent water is only taken from the clear water layer out of the outlet tee through specialized filters that further purify the wastewater.

3. DISPERSAL

After primary treatment, the water needs a place to go. Effluent water flows out of the septic tank by gravity or with a pump to a drainfield that disperses the water back into the ground. Effluent water is dispersed by pipes and allowed to naturally percolate through the soil to restore sources of groundwater. In many cases, the drainfields continue to filter out forms of nitrogen and phosphorous that could be detrimental to the environment. This water has now been purified, and can be safely returned to ground water or surface water sources.

Conventionally, septic systems should be replaced after 25 years. Years of use gradually upset the ratio of organic solids in the system and the microorganisms that break them down, making the system ineffective. This process is known as progressive failure. However, external disturbances to the structure of the system and improper usage could cause failure before the system’s lifetime is exceeded. There are three indicators of a failed system that homeowners should consider to protect the environment and their families.

1. DYE TESTS

One of the more common practices to test for leakage in septic systems are dye tests. Environmentally friendly dye is flushed down the property’s toilet. If there is a failure in the system, the dye will appear immediately in the groundwater or surface water, depending on the site. This is typically done by government jurisdictions every couple of years to detect gross failure within watersheds.

2. SURFACE SEEPAGE

Visual detection of sewage on the property is a red flag of a failed system, and must be dealt with immediately. The contaminated area should be quarantined to eliminate human and animal contact to reduce health risks. Please contact us for further instruction.

3. PROFESSIONAL MEASUREMENTS

Even though your system may pass the dye test and there is no visual instances of sewage on the property, it is not guaranteed that your system is perfect. Water that is recycled into the environment must meet concentration levels dictated by the EPA and your local environmental agencies in order to ensure the safety of the environment and the public. These contaminants are difficult to detect without the proper sampling tools and equipment. Professionally measured biological, physical, and chemical properties include:

• Total Phosphorus (P
• Total Coliform
• Fecal Coliform
• BOD & TSS
• Ammonia (NO3-N)
• Nitrite-Nitrate (NO2-NO3)
• TKN
• Turbidity

We seek the simplest, most effective means of installing, replacing, or expanding septic systems to meet the needs of your property. After years in the industry, we are yet to find a challenge that we haven’t been able to overcome, including sensitive lakefront properties that flow into drinking water sources. This is a breakdown of the steps we take for each project:

1. SITE INVESTIGATION

Land and soil characteristics present unique challenges on each project and ultimately dictates the complexity of the system. These are some of the factors we look for:

• Slope of Grade
• Regulatory Distance Requirements
• Individual Lot Size

At every site, we also take a look at the structure and characteristics of the soil below grade to determine the best system for your site needs. These characteristics include:

• Soil Composition
• Proximity to Water Table
• Hydraulic Conductivity (Percolation Rate)

4-6 foot deep test holes are excavated at key points on the property to gain insight into soil composition and seasonal high water table. We typically want at least 2 feet of soil above the water table for structural purposes and to determine how the land profile will need to be manipulated. The percolation test tells us the rate of water infiltration into the natural soil, allowing us to size the drainfield and determine if new fill material will need to be imported onto the site.

2. ENGINEERING DESIGN

With a complete understanding of natural land features, we will design and develop your onsite wastewater treatment system and generate professional design drawings that will be approved by local regulatory agencies.

3. CONSTRUCTION

With approved drawings, a contractor is hired to ensure that the septic system is properly installed though professional experience and frequent communication with the engineer. We are happy to give referrals, but the choice of a contractor is ultimately up to you.

4. MAINTENANCE

Proper maintenance of your septic system is necessary in order to preserve the functionality of the system and the health of the environment and the public. Damaged systems costs thousands of dollars to fix or replace, and diminishes the worth of your property if poorly maintained.

The EPA specifies the top four contributions by a homeowner to protect their septic system:

• Regularly inspect and pump the system as necessary
• Use water efficiently
• Do not dispose of hazardous wastes in sinks or toilets
• Care for your drainfield

The selection of a septic system is dictated by water usage and site characteristics. As septic technology advances, older systems are slowly replaced and cycled out of the market. This is an overview of the different septic systems that we frequently install or replace, and provide guidance in our selection process.

OUTDATED SYSTEMS

Outdated and under performing septic systems will ultimately lead to failure and contamination problems. Two common systems are drywells and cesspools. These systems collect property wastewater in an underground chamber, and offer little to no treatment before leaching into native soil. When the site characteristics of a client’s property limits the use and implementation of a dispersal field and the existing drywells must be used, we use other means to pretreat and disinfect the wastewater before it flows into the legacy system. This successfully achieves sanitation levels in more complex situations.