1. Tank Size
The size of the tank determines the installation cost, how often you need to pump the tank, and even how long your tank will last. Although septic tank sizing is a precise science, the following factors can give you a rough estimate of the size of the tank you should install.
2. Drainfield Size
The septic drainfield (or leach field) is the area where the actual absorption of treated wastes takes place. After the bacteria digests the wastes in the tank and separated the solids from the liquids, the solids sink to the bottom of the tank and the liquid exits the tank. The treated liquid then percolates slowly through the soil in the septic drainfield.
3. Drainfield Location
You must choose the location of the drainfield carefully since the location determines the efficiency and longevity of the system. Here are some of the factors that determine drainfield location:
- The size of the land. You should have adequate space for the drainfield; otherwise, the drainfield will take a long time to absorb the wastes, and you will pollute the environment.
- The soil. Locate the drainfield in soil with good drainage; the soil should filter out effluent but allow liquid waste to seep deep into the ground.
- The terrain. The drainfield should not be on a steep slope; a steep slope would allow effluent to flow down the slope instead of into the soil.
4. Tank Material
Septic tanks are available in different materials all with their pros and cons. Here are some of the typical tank materials:
- Concrete. These tanks are relatively cheap and easy to install, but the tanks are susceptible to cracks.
- Steel. The tanks don’t crack, but they are susceptible to rust damage.
- Fiberglass. The tanks neither crack nor rust as is the case with both concrete and steel. Unfortunately, they are more susceptible to damage due to soil shifts.
Ultimately, your personal preferences, cost, the nature of the soil in your home, and the advice of the technician will help you decide which material is best for you.